21 CFR 520.23 - Acepromazine.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Acepromazine. 520.23 Section 520.23 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.23 Acepromazine. (a) Specifications. Each...

21 CFR 520.23 - Acepromazine.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Acepromazine. 520.23 Section 520.23 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.23 Acepromazine. (a) Specifications. Each...

Effects of maropitant, acepromazine, and electroacupuncture on vomiting associated with administration of morphine in dogs.

PubMed

Koh, Ronald B; Isaza, Natalie; Xie, Huisheng; Cooke, Kirsten; Robertson, Sheilah A

2014-04-01

To evaluate effects of maropitant, acepromazine, and electroacupuncture on morphine-related signs of nausea and vomiting in dogs and assess sedative effects of the treatments. Randomized controlled clinical trial. 222 dogs. Dogs received 1 of 6 treatments: injection of saline (0.9% NaCl) solution, maropitant citrate, or acepromazine maleate or electroacupuncture treatment at 1 acupoint, 5 acupoints, or a sham acupoint. Morphine was administered after 20 minutes of electroacupuncture treatment or 20 minutes after injectable treatment. Vomiting and retching events and signs of nausea and sedation were recorded. Incidence of vomiting and retching was significantly lower in the maropitant (14/37 [37.8%]) group than in the saline solution (28/37 [75.7%]) and sham-acupoint electroacupuncture (32/37 [86.5%]) groups. The number of vomiting and retching events in the maropitant (21), acepromazine (38), 1-acupoint (35), and 5-acupoint (34) groups was significantly lower than in the saline solution (88) and sham-acupoint electroacupuncture (109) groups. Incidence of signs of nausea was significantly lower in the acepromazine group (3/37 [8.1%]) than in the sham-acupoint group (15/37 [40.5%]). Mean nausea scores for the saline solution, maropitant, and sham-acupoint electroacupuncture groups increased significantly after morphine administration, whereas those for the acepromazine, 1-acupoint electroacupuncture, and 5-acupoint electroacupuncture groups did not. Mean sedation scores after morphine administration were significantly higher in dogs that received acepromazine than in dogs that received saline solution, maropitant, and sham-acupoint electroacupuncture treatment. Maropitant treatment was associated with a lower incidence of vomiting and retching, compared with control treatments, and acepromazine and electroacupuncture appeared to prevent an increase in severity of nausea following morphine administration in dogs.

Dose Regimens, Variability, and Complications Associated with Using Repeat-Bolus Dosing to Extend a Surgical Plane of Anesthesia in Laboratory Mice

PubMed Central

Jaber, Samer M; Hankenson, F Claire; Heng, Kathleen; McKinstry-Wu, Andrew; Kelz, Max B; Marx, James O

2014-01-01

Extending a surgical plane of anesthesia in mice by using injectable anesthetics typically is accomplished by repeat-bolus dosing. We compared the safety and efficacy of redosing protocols administered either during an anesthetic surgical plane (maintaining a continuous surgical plane, CSP), or immediately after leaving this plane (interrupted surgical plane, ISP) in C57BL/6J mice. Anesthesia was induced with ketamine, xylazine, and acepromazine (80, 8, and 1 mg/kg IP, respectively), and redosing protocols included 25% (0.25K), 50% (0.5K), or 100% (1.0K) of the initial ketamine dose or 25% (0.25KX) or 50% (0.5KX) of the initial ketamine–xylazine dose. In the ISP group, the surgical plane was extended by 13.8 ± 2.1 min (mean ± SEM) after redosing for the 0.25K redose with 50% returning to a surgical plane, 42.7 ± 4.5 min for the 0.5K redose with 88% returning to a surgical plane, and 44.3 ± 15.4 min for the 1.0K redose, 52.8 ± 7.2 min for the 0.25KX redose, and 45.9 ± 2.9 min for the 0.5KX redose, with 100% of mice returning to a surgical plane of anesthesia in these 3 groups. Mortality rates for ISP groups were 0%, 12%, 33%, 12%, and 18%, respectively. Mice in CSP groups had 50% mortality, independent of the repeat-dosing protocol. We recommend redosing mice with either 50% of the initial ketamine dose or 25% of the initial ketamine–xylazine dose immediately upon return of the pedal withdrawal reflex to extend the surgical plane of anesthesia in mice, optimize the extension of the surgical plane, and minimize mortality. PMID:25650976

Modulatory effects of ketamine, risperidone and lamotrigine on resting brain perfusion in healthy human subjects.

PubMed

Shcherbinin, Sergey; Doyle, Orla; Zelaya, Fernando O; de Simoni, Sara; Mehta, Mitul A; Schwarz, Adam J

2015-11-01

Resting brain perfusion, measured using the MRI-based arterial spin labelling (ASL) technique, is sensitive to detect central effects of single, clinically effective, doses of pharmacological compounds. However, pharmacological interaction experiments, such as the modulation of one drug response in the presence of another, have not been widely investigated using a task-free ASL approach. We assessed the effects of three psychoactive compounds (ketamine, risperidone and lamotrigine), and their interaction, on resting brain perfusion in healthy human volunteers. A multivariate Gaussian process classification (GPC) and more conventional univariate analyses were applied. The four pre-infusion conditions for each subject comprised risperidone, lamotrigine and two placebo sessions. The two placebo conditions enabled us to evaluate the classification performance in a test-retest setting, in addition to its performance in distinguishing the active oral drugs from placebo (direct effect on brain perfusion). The post ketamine- or saline-infusion scans allowed the effect of ketamine, and its interaction with risperidone and lamotrigine, on brain perfusion to be characterised. The pseudo-continuous ASL measurements of perfusion were sensitive to the effects of ketamine infusion and risperidone. The GPC captured consistent changes in perfusion across the group and contextualised the univariate changes with a larger pattern of regions contributing to accurate discrimination of ketamine from placebo. The findings argue against perfusion changes confounding in the previously described evoked BOLD response to ketamine and emphasise the blockade of the NMDA receptor over neuronal glutamate release in determining the perfusion changes induced by ketamine.

Ketamine and thiopental sodium: individual and combined neuroprotective effects on cortical cultures exposed to NMDA or nitric oxide.

PubMed

Shibuta, S; Varathan, S; Mashimo, T

2006-10-01

An N-methyl-D-aspartate (NMDA) blocker, ketamine, has been shown to be neuroprotective both in vivo and in vitro. However, ketamine is not commonly recommended for use in patients suffering from cerebral ischaemia because of its adverse neurological effects. We hypothesized that combined administration of ketamine and thiopental sodium (TPS) would be highly effective in protecting cerebral cortical neurones from ischaemia, with possibly reduced dosages. We examined the degree of neuroprotection provided by various concentrations of ketamine and TPS, alone and in combination, in cortical cultures exposed to NMDA or a nitric oxide-releasing compound (NOC-5) for 24 h. The survival rate (SR) of E16 Wistar rat cortical neurones was evaluated using photomicrographs before and after exposure to these compounds. The SRs of cortical neurones exposed to 30 microM NMDA or NOC-5 were 15.0 (3.8)%, 12.8 (3.1)%, respectively. Higher doses (5, 10 and 50 microM) but not lower doses (<1 microM) of ketamine improved SRs [57.9 (2.2)%, 61.1 (5.4)%, 76.7 (3.0)%, respectively] against NMDA but not NOC. Enhanced survival was observed with combined administration of 5 or 10 microM ketamine and 50 microM TPS [SR 71.3 (4.8)%, 74.7 (3.7)%, respectively, P<0.05 if ketamine alone, P<0.01 if TPS alone], against NMDA-induced neurotoxicity in vitro. Only the highest dose of TPS (50 microM) improved survival after NOC exposure. This neuroprotection was not influenced by ketamine. These data indicate that a low, clinically relevant dose of ketamine offer significant neuroprotection during prolonged exposure to NMDA but not to NOC. Combinations of reduced doses of ketamine and TPS exhibited enhanced neuroprotection against NMDA-induced neurotoxicity. Hence, combinations of these two common i.v. anaesthetics agents could be developed to protect the brain from ischaemia.

Effects of three methadone doses combined with acepromazine on sedation and some cardiopulmonary variables in dogs.

PubMed

Bitti, Flavia S; Campagnol, Daniela; Rangel, Julia Pp; Nunes Junior, Juarez S; Loureiro, Bárbara; Monteiro, Eduardo R

2017-03-01

To evaluate the sedative and cardiopulmonary effects of three methadone doses, combined with acepromazine, in dogs. Prospective, randomized, complete block study. Six healthy, adult, cross-bred dogs weighing 17.2±4.4 kg (mean±standard deviation). Each dog was administered four treatments: acepromazine (0.05 mg kg -1 ) alone or acepromazine (same dose) in combination with methadone (0.25, 0.50 or 0.75 mg kg -1 ). All drugs were administered intramuscularly. Sedation was scored by a numeric descriptive scale (NDS, range 0-3) and a simple numerical scale (SNS, range 0-10). Heart rate, invasive blood pressure, arterial blood gases and rectal temperature were measured at 15 to 30 minute intervals for 120 minutes. According to NDS scores, mild to moderate sedation (NDS=1-2) was observed in most dogs in the acepromazine treatment, with only one out of six dogs scored as exhibiting intense sedation (NDS=3). All treatments with methadone resulted in significantly higher SNS scores compared with acepromazine alone. In these treatments, most dogs exhibited intense sedation (NDS=3). Increasing the dose of methadone from 0.25 to 0.50 or 0.75 mg kg -1 prolonged sedation in a dose-related manner, but did not influence the degree of sedation. The main adverse effects following administration of acepromazine-methadone treatments were decreased blood pressure, mild respiratory acidosis and decreased rectal temperature. These effects were well tolerated and resolved without treatment. In this study in six dogs, acepromazine-methadone administration resulted in intense sedation in most dogs. The results are interpreted to indicate that a low dose of methadone (0.25 mg kg -1 ) administered in combination with acepromazine (0.05 mg kg -1 ) will induce short-term sedation in dogs, whereas higher doses of methadone should be administered when prolonged sedation is desired. Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

Antidepressant Potential of (R)-Ketamine in Rodent Models: Comparison with (S)-Ketamine.

PubMed

Fukumoto, Kenichi; Toki, Hidetoh; Iijima, Michihiko; Hashihayata, Takashi; Yamaguchi, Jun-Ichi; Hashimoto, Kenji; Chaki, Shigeyuki

2017-04-01

The rapid-acting and long-lasting antidepressant effects of ( R,S )-ketamine have recently gained much attention. Although ( S )-ketamine has been studied as an active isomer, recent evidence suggests that ( R )-ketamine exhibits longer-lasting antidepressant effects than ( S )-ketamine in rodents. However, the antidepressant potential of ( R )-ketamine has not been fully addressed. In the present study, we compared the antidepressant effects of ( R )-ketamine with those of ( S )-ketamine in animal models of depression, including a model that is refractory to current medications. Both ( R )-ketamine and ( S )-ketamine exhibited antidepressant effects at 30 minutes as well as at 24 hours after administration in forced-swimming and tail-suspension tests in mice. At 48 hours after administration, however, ( R )-ketamine still exerted a significant antidepressant effect in the tail-suspension test, whereas the effect of ( S )-ketamine was no longer observed. Moreover, ( R )-ketamine, but not ( S )-ketamine, significantly reversed the depressive-like behavior induced by repeated treatments with corticosterone in rats at 24 hours after a single administration. This effect was attenuated by an α -amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor antagonist, suggesting the involvement of AMPA receptor stimulation in the effects. Both ( R )-ketamine and ( S )-ketamine exhibited practically the same exposure levels in plasma, brain, and cerebrospinal fluid in mice and rats, and both compounds were rapidly eliminated from plasma (<4-8 hours). The present results confirmed the previous findings that ( R )-ketamine exerted longer-lasting antidepressant effects than ( S )-ketamine in animal models of depression. Moreover, our study is the first to demonstrate that ( R )-ketamine exerted a sustained antidepressant effect even in a model that is refractory to currently prescribed antidepressants. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Effects of treatment with oxytocin, xylazine butorphanol, guaifenesin, acepromazine, and detomidine on esophageal manometric pressure in conscious horses.

PubMed

Wooldridge, Anne A; Eades, Susan C; Hosgood, Giselle L; Moore, Rustin M

2002-12-01

To compare effects of oxytocin, acepromazine maleate, xylazine hydrochloride-butorphanol tartrate, guaifenesin, and detomidine hydrochloride on esophageal manometric pressure in horses. 8 healthy adult horses. A nasogastric tube, modified with 3 polyethylene tubes that exited at the postpharyngeal area, thoracic inlet, and distal portion of the esophagus, was fitted for each horse. Amplitude, duration, and rate of propagation of pressure waveforms induced by swallows were measured at 5, 10, 20, 30, and 40 minutes after administration of oxytocin, detomidine, acepromazine, xylazine-butorphanol, guaifenesin, or saline (0.9% NaCI) solution. Number of spontaneous swallows, spontaneous events (contractions that occurred in the absence of a swallow stimulus), and high-pressure events (sustained increases in baseline pressure of > 10 mm Hg) were compared before and after drug adminision. At 5 minutes after administration, detomidine increased waveform amplitude and decreased waveform duration at the thoracic inlet. At 10 minutes after administration, detomidine increased waveform duration at the thoracic inlet. Acepromazine administration increased the number of spontaneous events at the thoracic inlet and distal portion of the esophagus. Acepromazine and detomidine administration increased the number of high-pressure events at the thoracic inlet. Guaifenesin administration increased the number of spontaneous events at the thoracic inlet. Xylazine-butorphanol, detomidine, acepromazine, and guaifenesin administration decreased the number of spontaneous swallows. Detomidine, acepromazine, and a combination of xylazine butorphanol had the greatest effect on esophageal motility when evaluated manometrically. Reduction in spontaneous swallowing and changes in normal, coordinated peristaltic activity are the most clinically relevant effects.

Antagonism at the NR2B subunit of NMDA receptors induces increased connectivity of the prefrontal and subcortical regions regulating reward behavior.

PubMed

Gass, Natalia; Becker, Robert; Sack, Markus; Schwarz, Adam J; Reinwald, Jonathan; Cosa-Linan, Alejandro; Zheng, Lei; von Hohenberg, Christian Clemm; Inta, Dragos; Meyer-Lindenberg, Andreas; Weber-Fahr, Wolfgang; Gass, Peter; Sartorius, Alexander

2018-04-01

Evidence indicates that ketamine's rapid antidepressant efficacy likely results from its antagonism of NR2B-subunit-containing NMDA receptors (NMDAR). Since ketamine equally blocks NR2A- and NR2B-containing NMDAR, and has affinity to other receptors, NR2B-selective drugs might have improved therapeutic efficiency and side effect profile. We aimed to compare the effects of (S)-ketamine and two different types of NR2B-selective antagonists on functional brain networks in rats, in order to find common circuits, where their effects intersect, and that might explain their antidepressant action. The experimental design comprised four parallel groups of rats (N = 37), each receiving (S)-Ketamine, CP-101,606, Ro 25-6981 or saline. After compound injection, we acquired resting-state functional magnetic resonance imaging time series. We used graph theoretical approach to calculate brain network properties. Ketamine and CP-101,606 diminished the global clustering coefficient and small-worldness index. At the nodal level, all compounds induced increased connectivity of the regions mediating reward and cognitive aspects of emotional processing, such as ventromedial prefrontal cortex, septal nuclei, and nucleus accumbens. The dorsal hippocampus and regions involved in sensory processing and aversion, such as superior and inferior colliculi, exhibited an opposite effect. The effects common to ketamine and NR2B-selective compounds were localized to the same brain regions as those reported in depression, but in the opposite direction. The upregulation of the reward circuitry might partially underlie the antidepressant and anti-anhedonic effects of the antagonists and could potentially serve as a translational imaging phenotype for testing putative antidepressants, especially those targeting the NR2B receptor subtype.

Determination of ketamine and its main metabolites by liquid chromatography coupled to tandem mass spectrometry in pig plasma: Comparison of extraction methods.

PubMed

Ramiole, Cindy; D'Hayer, Benoit; Boudy, Vincent; Legagneux, Josette; Fonsart, Julien; Houzé, Pascal

2017-11-30

A rapid, sensitive and specific liquid chromatography coupled to tandem mass spectrometry method was developed for the simultaneous quantification pig plasma of ketamine and its two principal metabolites, norketamine and dehydronorketamine. Three extraction procoles were assessed including acetonitrile precipitation, Oase™ microplate extraction, and liquid-liquid extraction. Oase™ microplate extraction induced no significant matrix effect, important signal/noise ratio and good recoveries, ranging from 82 to 87% for the considered compounds. Using this extraction procedure, the assay was linear in the dynamic range 10-3000ng/mL (R 2 >0.99) regardless of the analytes. Intra- and inter-day accuracies were less than 12% for all compounds and intra- and inter-day precisions expressed as RSD were within <9.9%. Samples were stable in different storage conditions. High ketamine, norketamine and dehydronorketamine concentrations up to 15,000ng/mL can be determined with good precision using appropriate sample dilution. The assay was successfully applied to pig plasma samples to determine the pharmacokinetics of ketamine and the consecutive metabolites after buccal administration of a 4mg/kg ketamine base solutions. Copyright © 2017 Elsevier B.V. All rights reserved.

Lack of Antidepressant Effects of (2R,6R)-Hydroxynorketamine in a Rat Learned Helplessness Model: Comparison with (R)-Ketamine.

PubMed

Shirayama, Yukihiko; Hashimoto, Kenji

2018-01-01

(R)-Ketamine exhibits rapid and sustained antidepressant effects in animal models of depression. It is stereoselectively metabolized to (R)-norketamine and subsequently to (2R,6R)-hydroxynorketamine in the liver. The metabolism of ketamine to hydroxynorketamine was recently demonstrated to be essential for ketamine's antidepressant actions. However, no study has compared the antidepressant effects of these 3 compounds in animal models of depression. The effects of a single i.p. injection of (R)-ketamine, (R)-norketamine, and (2R,6R)-hydroxynorketamine in a rat learned helplessness model were examined. A single dose of (R)-ketamine (20 mg/kg) showed an antidepressant effect in the rat learned helplessness model. In contrast, neither (R)-norketamine (20 mg/kg) nor (2R,6R)-hydroxynorketamine (20 and 40 mg/kg) did so. Unlike (R)-ketamine, its metabolite (2R,6R)-hydroxynorketamine did not show antidepressant actions in the rat learned helplessness model. Therefore, it is unlikely that the metabolism of ketamine to hydroxynorketamine is essential for ketamine's antidepressant actions. © The Author 2017. Published by Oxford University Press on behalf of CINP.

Differential regulation of GluA1 expression by ketamine and memantine.

PubMed

Zhang, Ke; Yamaki, Vitor Nagai; Wei, Zhisheng; Zheng, Yu; Cai, Xiang

2017-01-01

Evidence from preclinical and clinical studies shows that ketamine, a noncompetitive NMDA receptor antagonist, exerts rapid and sustained antidepressant responses. However, ketamine's psychotomimetic side effects and abuse liability limit the clinical use of the compound. Interestingly, memantine, another NMDA receptor channel blocker, processes no defined antidepressant property but is much safer and clinical tolerated. Understanding why ketamine but not memantine exhibits rapid antidepressant responses is important to elucidate the cellular signaling underlying the fast antidepressant actions of ketamine and to design a new safer generation of fast-acting antidepressants. Here we show that ketamine but memantine caused a rapid and sustained antidepressant-like responses in forced swim test (FST). Both drugs enhanced GluA1 S845 phosphorylation and potentiated Schaffer collateral-CA1 synaptic transmission. However, ketamine but not memantine elevated the expression of GluA1. Incubating acutely prepared hippocampal slices with ketamine but not memantine enhanced mTOR phosphorylation in a time course parallel to the time course of GluA1 elevation. Our results suggest that distinct properties in regulation of mTOR phosphorylation and synaptic protein expression may underlie the differential effectiveness of ketamine and memantine in their antidepressant responses. Copyright © 2016 Elsevier B.V. All rights reserved.

Leptospira infections in trappers from Ontario

PubMed Central

Warshawsky, Bryna; Lindsay, L Robbin; Artsob, Harvey

2000-01-01

BACKGROUND: Four trappers presented to the Middlesex-London Health Unit in November, 1997 with similar clinical presentations. All four complained of fever, chills and headache, and three of the four had severe muscle aches. All gave histories of trapping raccoons before the onset of illness. Three of the four men exhibited diagnostic seroconversions to Leptospira grippotyphosa. OBJECTIVE: To describe the four suspected cases of leptospira infections and to determine whether raccoons might serve as a reservoir of infection using field studies. DESIGN: Raccoon serology were undertaken using the microscopic agglutination test against eight serovars of Leptospira interrogans including L grippotyphosa. Raccoons were trapped using Tomahawk live traps, anaesthetized with intramuscular injection of ketamine and acepromazine, bled by cardiac puncture and released. RESULTS: Forty-two raccoons were trapped in Middlesex (n=36) and Kent counties (n=6) from April 25 to May 2, 1998, and 10 (23.8%) of these animals had antibodies to L grippotyphosa. CONCLUSIONS: Infections due to L grippotyphosa or a closely related serovar are a risk for trappers in Ontario, and raccoons are a likely reservoir of this bacterium. PMID:18159265

Evaluation of the Percutaneous Absorption of Ketamine HCl, Gabapentin, Clonidine HCl, and Baclofen, in Compounded Transdermal Pain Formulations, Using the Franz Finite Dose Model.

PubMed

Bassani, August S; Banov, Daniel

2016-02-01

This study evaluates the ability of four commonly used analgesics (ketamine HCl, gabapentin, clonidine HCl, and baclofen), when incorporated into two transdermal compounding bases, Lipoderm and Lipoderm ActiveMax, to penetrate human cadaver trunk skin in vitro, using the Franz finite dose model. In vitro experimental study. Methods. Ketamine HCl 5% w/w, gabapentin 10% w/w, clonidine HCl 0.2% w/w, and baclofen 2% w/w were compounded into two transdermal bases, Lipoderm and Lipoderm ActiveMax. Each compounded drug formulation was tested on skin from three different donors and three replicate skin sections per donor. The Franz finite dose model was used in this study to evaluate the percutaneous absorption and distribution of drugs within each formulation. Rapid penetration to peak flux was detected for gabapentin and baclofen at approximately 1 hour after application. Clonidine HCl also had a rapid penetration to peak flux occurring approximately 1 hour after application and had a secondary peak at approximately 40 hours. Ketamine HCl exhibited higher overall absorption rates than the other drugs, and peaked at 6–10 hours. Similar patterns of drug distribution within the skin were also observed using both transdermal bases. This study suggests that the combination of these 4 analgesic drugs can be successfully delivered transdermally, using either Lipoderm or Lipoderm ActiveMax. Compounded transdermal drug preparations may then provide physicians with an alternative to traditional oral pain management regimens that can be personalized to the specific patient with the potential for enhanced pain control.

Intravenous anaesthesia using detomidine, ketamine and guaiphenesin for laparotomy in pregnant pony mares.

PubMed

Taylor, Polly M; Luna, Stelio Pl; White, Kate L; Bloomfield, Malcolm; Fowden, Abigail L

2001-07-01

Objective To characterize intravenous anaesthesia with detomidine, ketamine and guaiphenesin in pregnant ponies. Animals Twelve pony mares, at 260-320 days gestation undergoing abdominal surgery to implant fetal and maternal vascular catheters. Materials and methods Pre-anaesthetic medication with intravenous (IV) acepromazine (30 µg kg -1 ), butorphanol (20 µg kg -1 ) and detomidine (10 µg kg -1 ) preceded induction of anaesthesia with detomidine (10 µg kg -1 ) and ketamine (2 mg kg -1 ) IV Maternal arterial blood pressure was measured directly throughout anaesthesia and arterial blood samples were taken at 20-minute intervals for measurement of blood gases and plasma concentrations of cortisol, glucose and lactate. Anaesthesia was maintained with an IV infusion of detomidine (0.04 mg mL -1 ), ketamine (4 mg mL -1 ) and guaiphenesin (100 mg mL -1 ) (DKG) for 140 minutes. Oxygen was supplied by intermittent positive pressure ventilation (IPPV) adjusted to maintain PaCO 2 between 5.0 and 6.0 kPa (38 and 45 mm Hg), while PaO 2 was kept close to 20.0 kPa (150 mm Hg) by adding nitrous oxide. Simultaneous fetal and maternal blood samples were withdrawn at 90 minutes. Recovery quality was assessed. Results DKG was infused at 0.67 ± 0.17 mL kg -1 hour -1 for 1 hour then reduced, reaching 0.28 ± 0.14 mL kg -1 hour -1 at 140 minutes. Arterial blood gas values and pH remained within intended limits. During anaesthesia there was no change in heart rate, but arterial blood pressure decreased by 10%. Plasma glucose and lactate increased (10-fold and 2-fold, respectively) and cortisol decreased by 50% during anaesthesia. Fetal umbilical venous pH, PO 2 and PCO 2 were 7.34 ± 0.06, 5.8 ± 0.9 kPa (44 ± 7 mm Hg) and 6.7 ± 0.8 kPa (50 ± 6 mm Hg); and fetal arterial pH, PO 2 and PCO 2 were 7.29 ± 0.06, 4.0 ± 0.7 kPa (30 ± 5 mm Hg) and 7.8 ± 1.7 kPa (59 ± 13 mm Hg), respectively. Surgical conditions were good but four ponies required a single additional dose of ketamine. Ponies took 60 ± 28 minutes to stand and recovery was good. Conclusions and clinical relevance Anaesthesia produced with DKG was smooth while cardiovascular function in mare and fetus was well preserved. This indicates that DKG infusion is suitable for maintenance of anaesthesia in pregnant equidae. Copyright © 2001 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

N-acetylcysteine prevents ketamine-induced adverse effects on development, heart rate and monoaminergic neurons in zebrafish.

PubMed

Robinson, Bonnie; Dumas, Melanie; Gu, Qiang; Kanungo, Jyotshna

2018-06-08

N-acetylcysteine, a precursor molecule of glutathione, is an antioxidant. Ketamine, a pediatric anesthetic, has been implicated in cardiotoxicity and neurotoxicity including modulation of monoaminergic systems in mammals and zebrafish. Here, we show that N-acetylcysteine prevents ketamine's adverse effects on development and monoaminergic neurons in zebrafish embryos. The effects of ketamine and N-acetylcysteine alone or in combination were measured on the heart rate, body length, brain serotonergic neurons and tyrosine hydroxylase-immunoreactive (TH-IR) neurons. In the absence of N-acetylcysteine, a concentration of ketamine that produces an internal embryo exposure level comparable to human anesthetic plasma concentrations significantly reduced heart rate and body length and those effects were prevented by N-acetylcysteine co-treatment. Ketamine also reduced the areas occupied by serotonergic neurons in the brain, whereas N-acetylcysteine co-exposure counteracted this effect. TH-IR neurons in the embryo brain and TH-IR cells in the trunk were significantly reduced with ketamine treatment, but not in the presence of N-acetylcysteine. In our continued search for compounds that can prevent ketamine toxicity, this study using specific endpoints of developmental toxicity, cardiotoxicity and neurotoxicity, demonstrates protective effects of N-acetylcysteine against ketamine's adverse effects. This is the first study that shows the protective effects of N-acetylcysteine on ketamine-induced developmental defects of monoaminergic neurons as observed in a whole organism. Published by Elsevier B.V.

Lack of Antidepressant Effects of (2R,6R)-Hydroxynorketamine in a Rat Learned Helplessness Model: Comparison with (R)-Ketamine

PubMed Central

Shirayama, Yukihiko

2018-01-01

Abstract Background (R)-Ketamine exhibits rapid and sustained antidepressant effects in animal models of depression. It is stereoselectively metabolized to (R)-norketamine and subsequently to (2R,6R)-hydroxynorketamine in the liver. The metabolism of ketamine to hydroxynorketamine was recently demonstrated to be essential for ketamine’s antidepressant actions. However, no study has compared the antidepressant effects of these 3 compounds in animal models of depression. Methods The effects of a single i.p. injection of (R)-ketamine, (R)-norketamine, and (2R,6R)-hydroxynorketamine in a rat learned helplessness model were examined. Results A single dose of (R)-ketamine (20 mg/kg) showed an antidepressant effect in the rat learned helplessness model. In contrast, neither (R)-norketamine (20 mg/kg) nor (2R,6R)-hydroxynorketamine (20 and 40 mg/kg) did so. Conclusions Unlike (R)-ketamine, its metabolite (2R,6R)-hydroxynorketamine did not show antidepressant actions in the rat learned helplessness model. Therefore, it is unlikely that the metabolism of ketamine to hydroxynorketamine is essential for ketamine’s antidepressant actions. PMID:29155993

Comparison of R-ketamine and rapastinel antidepressant effects in the social defeat stress model of depression.

PubMed

Yang, Bangkun; Zhang, Ji-Chun; Han, Mei; Yao, Wei; Yang, Chun; Ren, Qian; Ma, Min; Chen, Qian-Xue; Hashimoto, Kenji

2016-10-01

The N-methyl-D-aspartate (NMDA) receptor antagonists, including R-ketamine and rapastinel (formerly GLYX-13), show rapid antidepressant effects in animal models of depression. We compared the rapid and sustained antidepressant effects of R-ketamine and rapastinel in the social defeat stress model. In the tail suspension and forced swimming tests, R-ketamine (10 mg/kg, intraperitoneal (i.p.)) or rapastinel (10 mg/kg, i.p.) significantly attenuated the increased immobility time in the susceptible mice, compared with the vehicle-treated group. In the sucrose preference test, both compounds significantly enhanced the reduced preference in susceptible mice 2, 4, or 7 days after a single injection. All mice were sacrificed 8 days after a single injection. Western blot analyses showed that R-ketamine, but not rapastinel, significantly attenuated the reduced brain-derived neurotrophic factor (BDNF)-TrkB signaling, postsynaptic density protein 95 (PSD-95), and GluA1 (a subtype of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor) in the prefrontal cortex, dentate gyrus, and CA3 of the hippocampus in the susceptible mice. In contrast, both compounds had no effect against the increased BDNF-TrkB signaling, PSD-95, and GluA1 seen in the nucleus accumbens of susceptible mice. Moreover, sustained antidepressant effect of R-ketamine (3 mg/kg, intravenous (i.v.)), but not rapastinel (3 mg/kg, i.v.), was detected 7 days after a single dose. These results highlight R-ketamine as a longer lasting antidepressant compared with rapastinel in social defeat stress model. It is likely that synaptogenesis including BDNF-TrkB signaling in the prefrontal cortex (PFC) and hippocampus may be required for the mechanisms promoting this sustained antidepressant effect.

Comparative study on the sedative effects of morphine, methadone, butorphanol or tramadol, in combination with acepromazine, in dogs.

PubMed

Monteiro, Eduardo Raposo; Junior, Adolfo Rodrigues; Assis, Hemir Martins Quirilos; Campagnol, Daniela; Quitzan, Juliany Gomes

2009-01-01

To compare the effects of morphine (MOR), methadone (MET), butorphanol (BUT) and tramadol (TRA), in combination with acepromazine, on sedation, cardiorespiratory variables, body temperature and incidence of emesis in dogs. Prospective randomized, blinded, experimental trial. Six adult mixed-breed male dogs weighing 12.0 +/- 4.3 kg. Dogs received intravenous administration (IV) of acepromazine (0.05 mg kg(-1)) and 15 minutes later, one of four opioids was randomly administered IV in a cross-over design, with at least 1-week intervals. Dogs then received MOR 0.5 mg kg(-1); MET 0.5 mg kg(-1); BUT 0.15 mg kg(-1); or TRA 2.0 mg kg(-1). Indirect systolic arterial pressure (SAP), heart rate (HR), respiratory rate (f(R)), rectal temperature, pedal withdrawal reflex and sedation were evaluated at regular intervals for 90 minutes. Acepromazine administration decreased SAP, HR and temperature and produced mild sedation. All opioids further decreased temperature and MOR, BUT and TRA were associated with further decreases in HR. Tramadol decreased SAP whereas BUT decreased f(R) compared with values before opioid administration. Retching was observed in five of six dogs and vomiting occurred in one dog in MOR, but not in any dog in the remaining treatments. Sedation scores were greater in MET followed by MOR and BUT. Tramadol was associated with minor changes in sedation produced by acepromazine alone. When used with acepromazine, MET appears to provide better sedation than MOR, BUT and TRA. If vomiting is to be avoided, MET, BUT and TRA may be better options than MOR.

Comparison of detomidine and romifidine as premedicants before ketamine and halothane anesthesia in horses undergoing elective surgery.

PubMed

Taylor, P M; Bennett, R C; Brearley, J C; Luna, S P; Johnson, C B

2001-03-01

To compare detomidine hydrochloride and romifidine as premedicants in horses undergoing elective surgery. 100 client-owned horses. After administration of acepromazine (0.03 mg/kg, IV), 50 horses received detomidine hydrochloride (0.02 mg/kg of body weight, IV) and 50 received romifidine (0.1 mg/kg, IV) before induction and maintenance of anesthesia with ketamine hydrochloride (2 mg/kg) and halothane, respectively. Arterial blood pressure and blood gases, ECG, and heart and respiratory rates were recorded. Induction and recovery were timed and graded. Mean (+/- SD) duration of anesthesia for all horses was 104 +/- 28 minutes. Significant differences in induction and recovery times or grades were not detected between groups. Mean arterial blood pressure (MABP) decreased in both groups 30 minutes after induction, compared with values at 10 minutes. From 40 to 70 minutes after induction, MABP was significantly higher in detomidine-treated horses, compared with romifidine-treated horses, although more romifidine-treated horses received dobutamine infusions. In all horses, mean respiratory rate ranged from 9 to 11 breaths/min, PaO2 from 200 to 300 mm Hg, PaCO2 from 59 to 67 mm Hg, arterial pH from 7.33 to 7.29, and heart rate from 30 to 33 beats/min, with no significant differences between groups. Detomidine and romifidine were both satisfactory premedicants. Romifidine led to more severe hypotension than detomidine, despite administration of dobutamine to more romifidine-treated horses. Both detomidine and romifidine are acceptable alpha2-adrenoceptor agonists for use as premedicants before general anesthesia in horses; however, detomidine may be preferable when maintenance of blood pressure is particularly important.

The Modification and Performance of a Large Animal Anesthesia Machine (Tafonius®) in Order to Deliver Xenon to a Horse.

PubMed

Santangelo, Bruna; Robin, Astrid; Simpson, Keith; Potier, Julie; Guichardant, Michel; Portier, Karine

2017-01-01

Xenon, due to its interesting anesthetic properties, could improve the quality of anesthesia protocols in horses despite its high price. This study aimed to modify and test an anesthesia machine capable of delivering xenon to a horse. An equine anesthesia machine (Tafonius, Vetronic Services Ltd., UK) was modified by including a T-connector in the valve block to introduce xenon, so that the xenon was pushed into the machine cylinder by the expired gases. A xenon analyzer was connected to the expiratory limb of the patient circuit. The operation of the machine was modeled and experimentally tested for denitrogenation, wash-in, and maintenance phases. The system was considered to consist of two compartments, one being the horse's lungs, the other being the machine cylinder and circuit. A 15-year-old, 514-kg, healthy gelding horse was anesthetized for 70 min using acepromazine, romifidine, morphine, diazepam, and ketamine. Anesthesia was maintained with xenon and oxygen, co-administered with lidocaine. Ventilation was controlled. Cardiorespiratory variables, expired fraction of xenon (FeXe), blood gases were measured and xenon was detected in plasma. Recovery was unassisted and recorded. FeXe remained around 65%, using a xenon total volume of 250 L. Five additional boli of ketamine were required to maintain anesthesia. PaO 2 was 45 ± 1 mmHg. The recovery was calm. Xenon was detected in blood during the entire administration time. This pilot study describes how to deliver xenon to a horse. Although many technical problems were encountered, their correction could guide future endeavors to study the use of xenon in horses.

Antinociceptive effects, metabolism and disposition of ketamine in ponies under target-controlled drug infusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knobloch, M.; Portier, C.J.; Levionnois, O.L.

2006-11-01

Ketamine is widely used as an anesthetic in a variety of drug combinations in human and veterinary medicine. Recently, it gained new interest for use in long-term pain therapy administered in sub-anesthetic doses in humans and animals. The purpose of this study was to develop a physiologically based pharmacokinetic (PBPk) model for ketamine in ponies and to investigate the effect of low-dose ketamine infusion on the amplitude and the duration of the nociceptive withdrawal reflex (NWR). A target-controlled infusion (TCI) of ketamine with a target plasma level of 1 {mu}g/ml S-ketamine over 120 min under isoflurane anesthesia was performed inmore » Shetland ponies. A quantitative electromyographic assessment of the NWR was done before, during and after the TCI. Plasma levels of R-/S-ketamine and R-/S-norketamine were determined by enantioselective capillary electrophoresis. These data and two additional data sets from bolus studies were used to build a PBPk model for ketamine in ponies. The peak-to-peak amplitude and the duration of the NWR decreased significantly during TCI and returned slowly toward baseline values after the end of TCI. The PBPk model provides reliable prediction of plasma and tissue levels of R- and S-ketamine and R- and S-norketamine. Furthermore, biotransformation of ketamine takes place in the liver and in the lung via first-pass metabolism. Plasma concentrations of S-norketamine were higher compared to R-norketamine during TCI at all time points. Analysis of the data suggested identical biotransformation rates from the parent compounds to the principle metabolites (R- and S-norketamine) but different downstream metabolism to further metabolites. The PBPk model can provide predictions of R- and S-ketamine and norketamine concentrations in other clinical settings (e.g. horses)« less

Determination of ketamine and its major metabolite, norketamine, in urine and plasma samples using microextraction by packed sorbent and gas chromatography-tandem mass spectrometry.

PubMed

Moreno, Ivo; Barroso, Mário; Martinho, Ana; Cruz, Angelines; Gallardo, Eugenia

2015-11-01

Ketamine is a club drug widely abused for its hallucinogenic effects, being also used as a "date-rape" drug in recent years. We have developed an analytical method using gas chromatography-tandem mass spectrometry (GC-MS/MS) for the identification and quantification of ketamine and its major metabolite in urine and plasma. No derivatization step is needed to accomplish analysis. The compounds were extracted from 0.25mL of sample using microextraction by packed sorbent on mixed mode (M1) cartridges. Calibration curves were linear in the range of 10-250ng/mL for urine and 10-500ng/mL for plasma, with determination coefficients higher than 0.99. The limit of detection (LOD) was 5ng/mL for both compounds in both specimens. Recoveries ranged from 63 to 101%, while precision and accuracy were below 14% and 15%, respectively. These low limits of detection and the quite high recoveries obtained, in very low sample amounts, allow detecting small quantities of the compounds, making this procedure suitable for those laboratories performing routine analysis in the field of forensic toxicology. Compared with existing methods, the herein described procedure is fast, since no derivatization step is required, and cost effective for the quantification of ketamine and norketamine in biological specimens by gas chromatography. Copyright © 2015 Elsevier B.V. All rights reserved.

Creatine, Similar to Ketamine, Counteracts Depressive-Like Behavior Induced by Corticosterone via PI3K/Akt/mTOR Pathway.

PubMed

Pazini, Francis L; Cunha, Mauricio P; Rosa, Julia M; Colla, André R S; Lieberknecht, Vicente; Oliveira, Ágatha; Rodrigues, Ana Lúcia S

2016-12-01

Ketamine has emerged as a novel strategy to treat refractory depression, producing rapid remission, but elicits some side effects that limit its use. In an attempt to investigate a safer compound that may afford an antidepressant effect similar to ketamine, this study examined the effects of the ergogenic compound creatine in a model of depression, and the involvement of phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway in its effect. In order to induce a depressive-like behavior, mice were administered with corticosterone (20 mg/kg, per os (p.o.)) for 21 days. This treatment increased immobility time in the tail suspension test (TST), an effect abolished by a single administration of creatine (10 mg/kg, p.o.) or ketamine (1 mg/kg, i.p.), but not by fluoxetine (10 mg/kg, p.o., conventional antidepressant). Treatment of mice with wortmannin (PI3K inhibitor, 0.1 μg/site, intracerebroventricular (i.c.v.)) or rapamycin (mTOR inhibitor, 0.2 nmol/site, i.c.v.) abolished the anti-immobility effect of creatine and ketamine. None of the treatments affected locomotor activity of mice. The immunocontents of p-mTOR, p-p70S6 kinase (p70S6K), and postsynaptic density-95 protein (PSD95) were increased by creatine and ketamine in corticosterone or vehicle-treated mice. Moreover, corticosterone-treated mice presented a decreased hippocampal brain-derived neurotrophic factor (BDNF) level, an effect abolished by creatine or ketamine. Altogether, the results indicate that creatine shares with ketamine the ability to acutely reverse the corticosterone-induced depressive-like behavior by a mechanism dependent on PI3K/AKT/mTOR pathway, and modulation of the synaptic protein PSD95 as well as BDNF in the hippocampus, indicating the relevance of targeting these proteins for the management of depressive disorders. Moreover, we suggest that creatine should be further investigated as a possible fast-acting antidepressant.

Effects of acepromazine or methadone on midazolam-induced behavioral reactions in dogs

PubMed Central

Simon, Bradley T.; Scallan, Elizabeth M.; Siracusa, Carlo; Henderson, Amy; Sleeper, Meg M.; Larenza Menzies, M. Paula

2014-01-01

This study evaluated whether acepromazine or methadone reduced behavioral parameters, overall excitement, and activity associated with midazolam administration to healthy dogs. Dogs received midazolam (M) alone [M: 0.25 mg/kg body weight (BW)] or with methadone (MM) (MM: 0.75 mg/kg BW) or acepromazine (MA) (MA: 0.03 mg/kg BW) or saline (S) solution alone, all intramuscularly. Two blinded observers evaluated behavioral parameters using video recordings 30 min before and after injection of drugs. Accelerometery was used to evaluate “total activity counts” (TAC) at baseline and post-treatment. Post-treatment excitement scores were significantly higher in M and MA compared to baseline, M and MM compared to S, and M compared to MA. Behavioral parameters showed significantly higher proportions of “pacing” post-treatment in all groups receiving midazolam, and “restlessness,” “chewing/licking,” and “sniffing” in M. No significant differences were found for TAC at baseline and post-treatment. Midazolam-induced paradoxical behavioral changes (excitation, panting, pacing, restlessness, licking/chewing, and vocalization) were not prevented by acepromazine or methadone in healthy dogs. PMID:25183896

The role of adipokines in the rapid antidepressant effects of ketamine.

PubMed

Machado-Vieira, R; Gold, P W; Luckenbaugh, D A; Ballard, E D; Richards, E M; Henter, I D; De Sousa, R T; Niciu, M J; Yuan, P; Zarate, C A

2017-01-01

We previously found that body mass index (BMI) strongly predicted response to ketamine. Adipokines have a key role in metabolism (including BMI). They directly regulate inflammation and neuroplasticity pathways and also influence insulin sensitivity, bone metabolism and sympathetic outflow; all of these have been implicated in mood disorders. Here, we sought to examine the role of three key adipokines-adiponectin, resistin and leptin-as potential predictors of response to ketamine or as possible transducers of its therapeutic effects. Eighty treatment-resistant subjects who met DSM-IV criteria for either major depressive disorder (MDD) or bipolar disorder I/II and who were currently experiencing a major depressive episode received a single ketamine infusion (0.5 mg kg -1 for 40 min). Plasma adipokine levels were measured at three time points (pre-infusion baseline, 230 min post infusion and day 1 post infusion). Overall improvement and response were assessed using percent change from baseline on the Montgomery-Asberg Depression Rating Scale and the Hamilton Depression Rating Scale. Lower baseline levels of adiponectin significantly predicted ketamine's antidepressant efficacy, suggesting an adverse metabolic state. Because adiponectin significantly improves insulin sensitivity and has potent anti-inflammatory effects, this finding suggests that specific systemic abnormalities might predict positive response to ketamine. A ketamine-induced decrease in resistin was also observed; because resistin is a potent pro-inflammatory compound, this decrease suggests that ketamine's anti-inflammatory effects may be transduced, in part, by its impact on resistin. Overall, the findings suggest that adipokines may either predict response to ketamine or have a role in its possible therapeutic effects.

Sedative and cardiorespiratory effects of low doses of xylazine with and without acepromazine in Nordestino donkeys.

PubMed

Lucas Castillo, J A; Gozalo-Marcilla, M; Werneck Fonseca, M; Possebon, F S; da Rosa, A C; de Araujo Aguiar, A J

2018-03-22

Information on appropriate protocols for sedation of Nordestino donkeys is scarce. To evaluate the sedative and cardiorespiratory effects of low doses of intravenous (i.v.) xylazine with and without acepromazine in 'Nordestino' donkeys. Seven healthy female Nordestino donkeys (150 ± 18 kg) were included in this blinded, randomised, crossover experiment. Four treatments were administered, consisting of two i.v. injections, at baseline (T0, 1st injection) and 15 min later (T15, 2nd injection). Treatments included acepromazine 0.05 mg/kg bwt + saline (AS), saline + xylazine 0.5 mg/kg bwt (SX0.5), acepromazine + xylazine 0.25 mg/kg bwt (AX0.25) or acepromazine + xylazine 0.5 mg/kg bwt (AX0.5). Sedative and cardiorespiratory parameters were evaluated before T0 and 15, 20, 30, 45, 60, 75 and 90 min after treatment. Degree [height of head above ground (HHAG)] and quality of sedation [ataxia, responses to stimuli and visual analogue scale (VAS) scoring] and respiratory rate were evaluated by the main investigator in situ, and heart rate was measured by an assistant investigator. Three experienced evaluators assessed vídeos for ataxia and responses to stimuli. Normal data were analysed by repeated measures ANOVA, and non-normal by Kruskal-Wallis (P<0.05). HHAG was lower than baseline for 15 min after xylazine administration in AX0.25 and for 30 min in SX0.5 and AX0.5 groups. All treatments with xylazine increased VAS and ataxia scores in situ for 15 min after xylazine administration, with no differences between groups. Ataxia scores in situ were higher in SX0.5 and AX0.5 groups than AS for 15 and 30 min after xylazine administration, respectively. Absence of a negative control group (saline-saline). Acepromazine added to xylazine at 0.25 mg/kg bwt produced briefer and milder sedation than xylazine at 0.5 mg/kg bwt. © 2018 EVJ Ltd.

The sedative and behavioral effects of nalbuphine in dogs.

PubMed

Lester, Patrick A; Gaynor, James S; Hellyer, Peter W; Mama, Khursheed; Wagner, Ann E

2003-07-01

We compared the degree of sedation and frequency and intensity of adverse behaviors in dogs associated with nalbuphine when combined with acepromazine or xylazine compared with those of acepromazine or xylazine alone. Twenty-four dogs (13 female, 11 male) undergoing routine ovariohysterectomy or castration were randomly assigned to one of four groups. Group NX received 0.5 mg/kg nalbuphine and 0.5 mg/kg xylazine subcutaneously (s.c.). Group X received 0.5 mg/kg xylazine s.c. Group NA received 0.5 mg/kg nalbuphine and 0.05 mg/kg acepromazine s.c. Group A received 0.05 mg/kg acepromazine s.c. All dogs received 0.01 mg/kg glycopyrrolate s.c. All doses were administered preoperatively. Preoperative resting measurements of heart rate, respiratory rate, rectal temperature, and body weight were obtained. Sedation was scored both inside and outside a kennel prior to drug administration and at 10, 20, and 30 min after drug administration. Dogs were assessed for behavioral responses (leg withdrawal, shivering, rigidity, orienting, panting, struggling, vocalization, wide-eyed facial expression, breath holding, salivating, hiding, biting, or requiring a muzzle) during three time periods: placing the dog on the table, clipping and prepping of forelimb, and intravenous catheterization. Postoperative recovery behaviors were scored. Expired halothane concentrations were recorded at 15, 30, and 45 min postinduction. Significant differences occurred in the level of sedation at 30 min between dogs receiving nalbuphine and xylazine or xylazine only compared with dogs receiving acepromazine. There was a significant difference in behavioral scores with respect to leg withdrawal and orienting during clipping/prepping between dogs receiving nalbuphine and xylazine compared with dogs receiving xylazine. The combination of nalbuphine and xylazine is a useful premedicant which provided greater sedation than acepromazine and reduced some anxiety behaviors more than did xylazine alone. Nalbuphine is an inexpensive opioid and currently is not a controlled substance in the U.S.

S-Ketamine Mediates Its Acute and Sustained Antidepressant-Like Activity through a 5-HT1B Receptor Dependent Mechanism in a Genetic Rat Model of Depression.

PubMed

du Jardin, Kristian G; Liebenberg, Nico; Cajina, Manuel; Müller, Heidi K; Elfving, Betina; Sanchez, Connie; Wegener, Gregers

2017-01-01

Rationale: The mechanisms responsible for the unique antidepressant properties of ketamine have only been partly resolved. Recent preclinical reports implicate the neurotransmitter serotonin [5-hydroxytryptamine (5-HT)] in the antidepressant-like response of ketamine, and modulation of 5-HT 1B receptors has been hypothesized to attain an important role. Objectives: To evaluate the role of endogenous stimulation of 5-HT 1B heteroreceptors in the antidepressant-like activity of S -ketamine. Method: Flinders sensitive line (FSL) rats, a genetic model of depression, were depleted of endogenous 5-HT by 4-chloro-DL-phenylalanine methyl ester HCl administration (pCPA; 86 mg/kg/day for 3 days). In pCPA-pretreated and control FSL rats, the acute and sustained effects of a single dose of S -ketamine (15 mg/kg) and the selective 5-HT 1B receptor agonist CP94253 (1-6 mg/kg) alone and in combination with S -ketamine were studied in the forced swim test (FST), a commonly used assay that detects antidepressant activity. Results: pCPA pretreatment decreased cortical 5-HT levels to ∼6% but did not affect the baseline behavioral phenotype of FSL rats. S -ketamine demonstrated acute and sustained antidepressant-like activity, both of which were abolished by 5-HT depletion. Combining S -ketamine with a sub-effective dose of CP94253 (1 mg/kg) rescued S -ketamine's acute and sustained antidepressant-like effects, when CP94253 was administered 2 h prior to the FST. Co-administration of S -ketamine and CP94253 did not affect the plasma level of either compound, suggesting that the observed behavioral interaction could not be ascribed to a kinetic drug-drug interaction. Conclusion: 5-HT 1B receptor activation during testing appears to be critical for S -ketamine's antidepressant-like potentials in this model.

Neuroprotective and antioxidant effects of curcumin in a ketamine-induced model of mania in rats.

PubMed

Gazal, Marta; Valente, Matheus R; Acosta, Bruna A; Kaufmann, Fernanda N; Braganhol, Elizandra; Lencina, Claiton L; Stefanello, Francieli M; Ghisleni, Gabriele; Kaster, Manuella P

2014-02-05

Bipolar disorder (BD) is a chronic and debilitating illness characterized by recurrent manic and depressive episodes. Our research investigates the protective effects of curcumin, the main curcuminoid of the Indian spice turmeric, in a model of mania induced by ketamine administration in rats. Our results indicated that ketamine treatment (25 mg/kg, for 8 days) induced hyperlocomotion in the open-field test and oxidative damage in prefrontal cortex (PFC) and hippocampus (HP), evaluated by increased lipid peroxidation and decreased total thiol content. Moreover, ketamine treatment reduced the activity of the antioxidant enzymes superoxide dismutase and catalase in the HP. Pretreatment of rats with curcumin (20 and 50 mg/kg, for 14 days) or with lithium chloride (45 mg/kg, positive control) prevented behavioral and pro-oxidant effects induced by ketamine. These findings suggest that curcumin might be a good compound for preventive intervention in BD, reducing the episode relapse and the oxidative damage associated with the manic phase of this disorder. Copyright © 2013 Elsevier B.V. All rights reserved.

Sedation and mechanical antinociception after intravenous administration of detomidine in donkeys: a dosage-effect study.

PubMed

Lizarraga, Ignacio; Castillo-Alcala, Fernanda; Varner, Kelley M; Robinson, Lauren S

2015-02-21

There is limited, useful, scientific information on detomidine in donkeys. This study compared the effects of intravenous saline, detomidine (10, 13.5, 17 and 20 μg/kg) and acepromazine (50 μg/kg) in donkeys by computing areas under the curve for 0-30, 30-60 and 60-120 minutes (AUC0-30, AUC30-60 and AUC60-120) for sedation scores, head heights and mechanical nociceptive thresholds (MNTs). For sedation scores, all detomidine treatments, except 10 μg/kg, increased AUC0-30 values compared with saline, and AUC0-30 values were larger for 17 μg/kg detomidine than for acepromazine. All head height AUC values were lower for detomidine than for saline (except AUC60-120 for 10 μg/kg detomidine) and acepromazine (except AUC0-30 for 10 and 20 μg/kg detomidine, and AUC60-120 for 10 μg/kg detomidine). For MNTs, all detomidine treatments increased AUC0-30 and AUC30-60 values compared with saline and acepromazine; AUC30-60 values were smaller for 10 μg/kg than for 17 and 20 μg/kg detomidine. MNT AUC60-120 values were larger for 20 μg/kg detomidine than for saline, 10 μg/kg detomidine and acepromazine. Detomidine induced sedation and antinociception, but only antinociception was dosage dependent. Selection of detomidine dosage for donkeys may depend on the required duration of sedation and/or degree of analgesia. British Veterinary Association.

Comparison of the sedative effects of nalbuphine and butorphanol, alone or in combination with acepromazine in dogs.

PubMed

Gomes, Viviane H; Oliveira, Renato Ls; Marques, Juliana Lr; Coelho, Cassia Mm; Silva, Marta Fa

2018-01-01

To compare sedation and effects on heart rate (HR), mean arterial pressure (MAP) and respiratory rate (f R ) of nalbuphine and butorphanol, alone or combined with acepromazine in dogs. Prospective, randomized experimental trial. Eight healthy Beagle dogs, aged (mean ± standard deviation) 3.4 ± 0.5 years and weighing 11.0 ± 1.3 kg. Each dog was treated four times: physiological saline (1 mL) combined with nalbuphine (0.5 mg kg -1 ; SAL-NAL) or butorphanol (0.15 mg kg -1 ; SAL-BUT), and acepromazine (0.05 mg kg -1 ) combined with nalbuphine (0.5 mg kg -1 ; ACP-NAL) or butorphanol (0.15 mg kg -1 ; ACP-BUT), intravenously (IV). The degree of sedation, assessed by a numeric descriptive scale (NDS) and simple numerical scale (SNS), HR, MAP, f R and rectal temperature (RT), were recorded before and 20 minutes after administration of saline or acepromazine, then 15, 30, 60, 90 and 120 minutes after nalbuphine or butorphanol. Values were compared with baseline and among treatments. Mild sedation was recorded for SAL-NAL and SAL-BUT, and moderate sedation for ACP-NAL and ACP-BUT. NDS and SNS scores were higher for SAL-BUT and ACP-BUT at some time points when compared with SAL-NAL and ACP-NAL, respectively (p < 0.001). HR was lower in ACP-NAL than in ACP-BUT at 120 minutes and f R was lower in SAL-BUT than in SAL-NAL at 30 and 120 minutes (p < 0.05). RT was lower in SAL-BUT (37.5 ± 0.5 °C) compared with SAL-NAL (38.0 ± 0.5 °C) at 60-120 minutes (p < 0.05). Butorphanol promoted a higher sedative effect than nalbuphine when alone and combined with acepromazine. IV administration of nalbuphine or butorphanol, with or without acepromazine, at the doses studied, resulted in minimal decreases in MAP, HR, f R and RT. Copyright © 2017. Published by Elsevier Ltd.

Comparison of preoperative carprofen and postoperative butorphanol as postsurgical analgesics in cats undergoing ovariohysterectomy.

PubMed

Al-Gizawiy, Mona M; P Rudé, Elaine

2004-07-01

To compare carprofen to butorphanol, with regard to postsurgical analgesic effects, duration of analgesia, and adverse side effects. Blinded, randomized clinical study. Seventy-one cats, 0.5-5 years of age, weighing 3.24 +/- 0.61 kg, undergoing ovariohysterectomy (OHE). Cats were premedicated with subcutaneous atropine (0.04 mg kg(-1)), acepromazine (0.02 mg kg(-1)), and ketamine (5 mg kg(-1)). Anesthesia was induced with ketamine (5 mg kg(-1)) and diazepam (0.25 mg kg(-1)) given intravenously, and maintained with isoflurane. There were three treatment groups: group C (4 mg kg(-1) carprofen SC at induction), group B (0.4 mg kg(-1) butorphanol SC at end of surgery), and group S (0.08 mL kg(-1) of sterile saline SC at induction and end of surgery). Behavioral data were collected using a composite pain scale (CPS), prior to surgery (baseline) and 1, 2, 3, 4, 8, 12, 16, 20, and 24 hours post-surgery. Interaction scores were analyzed separately. Cats with CPS scores >12 received rescue analgesia (meperidine, 4 mg kg(-1), intramuscular). Sixty cats completed the study. The CPS scores did not differ significantly between groups C and B at any time period. CPS scores for groups B and C were significantly increased for 12 hours post-surgery, and in group S for 20 hours. Both group C and B CPS scores were significantly lower than group S in this 20-hour postoperative period, except at 4 hours (B and C) and at 3 and 8 hours (B alone). Interaction scores for group C returned to preoperative baseline 4 hours after surgery, while both groups B and S remained increased for at least 24 hours post-surgery. Nine cats required meperidine. In this study, carprofen provided better postsurgical analgesia than butorphanol. Clinical relevance Neither drug completely abolished pain, however preoperative carprofen provided better pain control compared with postoperative butorphanol in the 24-hour period following OHE surgery in cats.

Tone-Evoked Acoustic Change Complex (ACC) Recorded in a Sedated Animal Model.

PubMed

Presacco, Alessandro; Middlebrooks, John C

2018-05-10

The acoustic change complex (ACC) is a scalp-recorded cortical evoked potential complex generated in response to changes (e.g., frequency, amplitude) in an auditory stimulus. The ACC has been well studied in humans, but to our knowledge, no animal model has been evaluated. In particular, it was not known whether the ACC could be recorded under the conditions of sedation that likely would be necessary for recordings from animals. For that reason, we tested the feasibility of recording ACC from sedated cats in response to changes of frequency and amplitude of pure-tone stimuli. Cats were sedated with ketamine and acepromazine, and subdermal needle electrodes were used to record electroencephalographic (EEG) activity. Tones were presented from a small loudspeaker located near the right ear. Continuous tones alternated at 500-ms intervals between two frequencies or two levels. Neurometric functions were created by recording neural response amplitudes while systematically varying the magnitude of steps in frequency centered in octave frequency around 2, 4, 8, and 16 kHz, all at 75 dB SPL, or in decibel level around 75 dB SPL tested at 4 and 8 kHz. The ACC could be recorded readily under this ketamine/azepromazine sedation. In contrast, ACC could not be recorded reliably under any level of isoflurane anesthesia that was tested. The minimum frequency (expressed as Weber fractions (df/f)) or level steps (expressed in dB) needed to elicit ACC fell in the range of previous thresholds reported in animal psychophysical tests of discrimination. The success in recording ACC in sedated animals suggests that the ACC will be a useful tool for evaluation of other aspects of auditory acuity in normal hearing and, presumably, in electrical cochlear stimulation, especially for novel stimulation modes that are not yet feasible in humans.

Nociceptive thermal threshold testing in horses – effect of neuroleptic sedation and neuroleptanalgesia at different stimulation sites

PubMed Central

2013-01-01

Background Aim of the study was to compare the effect of neuroleptic sedation with acepromazine and neuroleptanalgesia with acepromazine and buprenorphine on thermal thresholds (TT) obtained at the nostrils and at the withers. The study was carried out as a randomized, blinded, controlled trial with cross-over design. Thermal thresholds were determined by incremental contact heat applied to the skin above the nostril (N) or the withers (W). Eleven horses were treated with saline (S), acepromazine (0.05 mg/kg) (ACE) or acepromazine and buprenorphine (0.0075 mg/kg) (AB) intravenously (IV). Single stimulations were performed 15 minutes prior and 15, 45, 75, 105, 165, 225, 285, 405 and 525 minutes after treatment. Sedation score, gastrointestinal auscultation score and occurrence of skin lesions were recorded. Data were analysed with analysis of variance for repeated measurements. Results There were no significant differences in TT between N and W with all treatments. The TT remained constant after S and there was no difference in TT between S and ACE. After AB there was a significant increase above baseline in TT until 405 minutes after treatment. Restlessness occurred 30–90 minutes after AB in 7 horses. All horses had reduced to absent borborygmi after AB administration for 165 to 495 minutes. Conclusion Thermal stimulation at both described body areas gives comparable results in the assessment of cutaneous anti-nociception in horses. There is no differential influence of neuroleptic sedation or neuroleptanalgesia on TTs obtained at N or W. Buprenorphine combined with acepromazine has a long lasting anti-nociceptive effect associated with the typical opioid induced side effects in horses. PMID:23837730

Evaluation of the antiemetic efficacy of maropitant in dogs medicated with morphine and acepromazine.

PubMed

Lorenzutti, A Matías; Martín-Flores, Manuel; Litterio, Nicolás J; Himelfarb, Martín A; Zarazaga, M Pilar

2016-03-01

To evaluate whether maropitant (1 mg kg(-1)) injected subcutaneously (SC), administered simultaneously or 30 minutes prior to intramuscular (IM) administration of morphine (0.5 mg kg(-1)) and acepromazine (0.05 mg kg(-1)), reduces the incidence of salivation, retching and emesis in dogs. Randomized, controlled, prospective clinical trial. Sixty dogs scheduled for an ovariohysterectomy as part of a population control program. Dogs were randomly allocated to be administered maropitant (1 mg kg(-1)) SC simultaneously (group M0) or 30 minutes prior to (group M30) administration of morphine (0.5 mg kg(-1)) and acepromazine (0.05 mg kg(-1)) IM. A control group was administered normal saline (C) at T-30 and T0. Dogs were observed for 30 minutes after morphine-acepromazine administration. The occurrence of vomiting, retching and salivation were recorded, as well as the time to first emesis and the number of emetic events per dog. The occurrence of salivation was not different between the groups. Retching and vomiting occurred significantly less frequently in M30 than in the other two groups (p < 0.02). The number of emetic events was also significantly less for M30 than for the other two groups (p = 0.01). When emesis occurred, the time to the first emetic event was similar among the groups. Maropitant (1 mg kg(-1)) SC reduced the frequency of morphine-induced emesis by as much as 70% when administered 30 minutes in advance. Simultaneous administration of maropitant and morphine-acepromazine produced no measurable effect on the frequency of retching or vomiting. © 2015 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

CYP2B6*6 allele and age substantially reduce steady-state ketamine clearance in chronic pain patients: impact on adverse effects

PubMed Central

Li, Yibai; Jackson, Kate A; Slon, Barry; Hardy, Janet R; Franco, Michael; William, Leeroy; Poon, Peter; Coller, Janet K; Hutchinson, Mark R; Currow, David C; Somogyi, Andrew A

2015-01-01

Aims Ketamine analgesia is limited by low intrinsic efficacy compounded by large interindividual variability in drug responses, possibly due to the heterogeneity in drug concentration. The CYP2B6*6 allele is associated with substantially reduced ketamine metabolism in vitro and, therefore, may affect ketamine clearance. Our aims were to examine the impact of the CYP2B6*6 allele on ketamine plasma clearance and on adverse effects in chronic pain patients. Methods CYP2B6 genotypes were identified in 49 chronic pain patients who received 24 h continuous subcutaneous infusions of ketamine. Steady-state plasma concentrations of ketamine (Css,k) and norketamine (Css,nk) were determined using HPLC. Results The median plasma clearance of ketamine after 100 mg 24 h–1 dose was significantly lower in patients with the CYP2B6*6/*6 (21.6 l h–1) and CYP2B6*1/*6 (40.6 l h–1) genotypes compared with patients with the CYP2B6*1/*1 genotype (68.1 l h–1, P < 0.001). The ketamine : norketamine plasma metabolic ratio was significantly higher in patients with the CYP2B6*6/*6 genotype than in those with the CYP2B6*1/*6 and the CYP2B6*1/*1 genotypes (P < 0.001). Patients who experienced adverse effects had lower plasma clearance (45.6 l h-1) than those who did not (52.6 l h-1, P = 0.04). The CYP2B6*6 genotype and age, and their combined impact explained 40%, 30% and 60% of the variation in Css,k, respectively. Similar results were observed after higher doses. Conclusions The CYP2B6*6 allele is associated with a substantial decrease in steady-state ketamine plasma clearance in chronic pain patients. The decreased clearance and resultant higher plasma concentrations may be associated with a higher incidence of ketamine adverse effects. PMID:25702819

CYP2B6*6 allele and age substantially reduce steady-state ketamine clearance in chronic pain patients: impact on adverse effects.

PubMed

Li, Yibai; Jackson, Kate A; Slon, Barry; Hardy, Janet R; Franco, Michael; William, Leeroy; Poon, Peter; Coller, Janet K; Hutchinson, Mark R; Currow, David C; Somogyi, Andrew A

2015-08-01

Ketamine analgesia is limited by low intrinsic efficacy compounded by large interindividual variability in drug responses, possibly due to the heterogeneity in drug concentration. The CYP2B6*6 allele is associated with substantially reduced ketamine metabolism in vitro and, therefore, may affect ketamine clearance. Our aims were to examine the impact of the CYP2B6*6 allele on ketamine plasma clearance and on adverse effects in chronic pain patients. CYP2B6 genotypes were identified in 49 chronic pain patients who received 24 h continuous subcutaneous infusions of ketamine. Steady-state plasma concentrations of ketamine (Css,k ) and norketamine (Css,nk ) were determined using HPLC. The median plasma clearance of ketamine after 100 mg 24 h(-1) dose was significantly lower in patients with the CYP2B6*6/*6 (21.6 l h(-1) ) and CYP2B6*1/*6 (40.6 l h(-1) ) genotypes compared with patients with the CYP2B6*1/*1 genotype (68.1 l h(-1) , P < 0.001). The ketamine : norketamine plasma metabolic ratio was significantly higher in patients with the CYP2B6*6/*6 genotype than in those with the CYP2B6*1/*6 and the CYP2B6*1/*1 genotypes (P < 0.001). Patients who experienced adverse effects had lower plasma clearance (45.6 l h(-1) ) than those who did not (52.6 l h(-1) , P = 0.04). The CYP2B6*6 genotype and age, and their combined impact explained 40%, 30% and 60% of the variation in Css,k , respectively. Similar results were observed after higher doses. The CYP2B6*6 allele is associated with a substantial decrease in steady-state ketamine plasma clearance in chronic pain patients. The decreased clearance and resultant higher plasma concentrations may be associated with a higher incidence of ketamine adverse effects. © 2015 The British Pharmacological Society.

Transcranial magnetic stimulation with acepromazine or dexmedetomidine in combination with levomethadone/fenpipramide in healthy Beagle dogs.

PubMed

Amendt, H-L; Siedenburg, J S; Steffensen, N; Söbbeler, F J; Schütter, A; Tünsmeyer, J; Rohn, K; Kästner, S B R; Tipold, A; Stein, V M

2016-11-01

The aim of this study was to evaluate the influence of two sedation protocols on transcranial magnetic motor evoked potentials (TMMEPs) after transcranial magnetic stimulation in medium sized dogs. Onset latencies and peak-to-peak amplitudes, elicited in the extensor carpi radialis and cranial tibial muscles, were analysed in 10 healthy Beagles that received either acepromazine or dexmedetomidine in combination with levomethadone/fenpipramide, in a crossover design. Similar TMMEP recordings could be made using both sedation protocols at 80-90% stimulation intensity; however, there were significantly shorter onset latencies with the acepromazine-levomethadone/fenpipramide protocol at 100% stimulation intensity. Reference values were established and it was concluded that both drug combinations are feasible for measuring TMMEPs in medium sized dogs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mechanisms of hypoxia-induced cerebrovascular dilation in the newborn pig.

PubMed

Leffler, C W; Smith, J S; Edrington, J L; Zuckerman, S L; Parfenova, H

1997-03-01

The hypothesis that endothelium-dependent components contribute to the cerebromicrovascular dilation to hypoxia in the newborn pig was addressed. Piglets anesthetized with ketamine-acepromazine and maintained on alpha-chloralose were equipped with closed cranial windows. Injury to the endothelium of pial arterioles was produced by light activation of fluorescein dye. Light/dye injury reduced the pial arteriolar dilation to hypoxia (5 min, arterial PO2 approximately 30 mmHg) from 57 +/- 9 to 19 +/- 5%. Light/dye injury abolished the pial arteriolar dilation to hypercapnia but did not affect dilation to sodium nitroprusside. The pial arteriolar dilation to hypoxia was not affected by tetrodotoxin, N(omega)-nitro-L-arginine, glibenclamide, iberiotoxin, charybdotoxin, tetraethylammonium, or 8-phenyltheophylline. Hypoxia caused increases in the cerebral cortical production of adenosine 3',5'-cyclic monophosphate and guanosine 3',5'-cyclic monophosphate. Cerebral vasodilation to hypoxia was inhibited by 5,8,11,14-eicosatetraynoic acid but was not greatly affected by cyclooxygenase or lipoxygenase inhibitors. In contrast, the cytochrome P-450 epoxygenase inhibitor miconazol decreased cerebral vasodilation to hypoxia from 45 +/- 5 to 17 +/- 4%. Therefore, the vascular endothelium appears to participate in cerebral microvascular dilation to hypoxia in newborn pigs. The mechanism may include cytochrome P-450 epoxygenase metabolites of arachidonic acid.

Rapid and Sustained Antidepressant Action of the mGlu2/3 Receptor Antagonist MGS0039 in the Social Defeat Stress Model: Comparison with Ketamine.

PubMed

Dong, Chao; Zhang, Ji-Chun; Yao, Wei; Ren, Qian; Ma, Min; Yang, Chun; Chaki, Shigeyuki; Hashimoto, Kenji

2017-03-01

Similar to the N-methyl-D-aspartate receptor antagonist ketamine, the metabotropic glutamate 2/3 receptor antagonist, MGS0039, shows antidepressant effects. However, there are no reports comparing these 2 compounds in the social defeat stress model of depression. We examined the effects of MGS0039 (1 mg/kg) and ketamine (10 mg/kg) on depression-like behavior in susceptible mice after repeated social defeat stress. Protein levels of brain-derived neurotrophic factor, TrkB, phospho-TrkB, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (GluA1), postsynaptic density protein 95, and dendritic spine density in selected brain regions were measured. In the tail suspension and forced swimming tests, both MGS0039 and ketamine significantly attenuated the increased immobility time observed in susceptible mice, compared with vehicle-treated animals, 1 or 2 days after a single dose of drug. In the sucrose preference test, both compounds significantly improved the reduced preference typically seen in susceptible mice at 3 to 7 days after a single dose of drug. Western-blot analyses showed that similar to ketamine, MGS0039 significantly attenuated the reduced brain-derived neurotrophic factor, phospho-TrkB/TrkB ratio, GluA1 and postsynaptic density protein 95 seen in the prefrontal cortex, dentate gyrus, and CA3 of the hippocampus from susceptible mice, 8 days after a single dose. Again, in a similar manner to ketamine, MGS0039 significantly attenuated the reduction of spine density in the prelimbic regions of the medial prefrontal cortex, dentate gyrus, and CA3 of the hippocampus, but not infralimbic regions of the medial prefrontal cortex and CA1, in susceptible mice 8 days after a single dose. In contrast, neither drug elicited an effect on altered brain-derived neurotrophic factor-TrkB signaling, GluA1, and postsynaptic density protein 95 levels and did not increase spine density observed in the nucleus accumbens of susceptible mice. Similar to ketamine, MGS0039 shows rapid and sustained antidepressant effects in the social defeat stress model. Long-lasting synaptogenesis in the prelimbic regions of medial prefrontal cortex, dentate gyrus, and CA3 might be implicated in this sustained antidepressant effect. © The Author 2016. Published by Oxford University Press on behalf of CINP.

Rapid and Sustained Antidepressant Action of the mGlu2/3 Receptor Antagonist MGS0039 in the Social Defeat Stress Model: Comparison with Ketamine

PubMed Central

Dong, Chao; Zhang, Ji-chun; Yao, Wei; Ren, Qian; Ma, Min; Yang, Chun; Chaki, Shigeyuki

2017-01-01

Abstract Background: Similar to the N-methyl-D-aspartate receptor antagonist ketamine, the metabotropic glutamate 2/3 receptor antagonist, MGS0039, shows antidepressant effects. However, there are no reports comparing these 2 compounds in the social defeat stress model of depression. Methods: We examined the effects of MGS0039 (1 mg/kg) and ketamine (10 mg/kg) on depression-like behavior in susceptible mice after repeated social defeat stress. Protein levels of brain-derived neurotrophic factor, TrkB, phospho-TrkB, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (GluA1), postsynaptic density protein 95, and dendritic spine density in selected brain regions were measured. Results: In the tail suspension and forced swimming tests, both MGS0039 and ketamine significantly attenuated the increased immobility time observed in susceptible mice, compared with vehicle-treated animals, 1 or 2 days after a single dose of drug. In the sucrose preference test, both compounds significantly improved the reduced preference typically seen in susceptible mice at 3 to 7 days after a single dose of drug. Western-blot analyses showed that similar to ketamine, MGS0039 significantly attenuated the reduced brain-derived neurotrophic factor, phospho-TrkB/TrkB ratio, GluA1 and postsynaptic density protein 95 seen in the prefrontal cortex, dentate gyrus, and CA3 of the hippocampus from susceptible mice, 8 days after a single dose. Again, in a similar manner to ketamine, MGS0039 significantly attenuated the reduction of spine density in the prelimbic regions of the medial prefrontal cortex, dentate gyrus, and CA3 of the hippocampus, but not infralimbic regions of the medial prefrontal cortex and CA1, in susceptible mice 8 days after a single dose. In contrast, neither drug elicited an effect on altered brain-derived neurotrophic factor-TrkB signaling, GluA1, and postsynaptic density protein 95 levels and did not increase spine density observed in the nucleus accumbens of susceptible mice. Conclusions: Similar to ketamine, MGS0039 shows rapid and sustained antidepressant effects in the social defeat stress model. Long-lasting synaptogenesis in the prelimbic regions of medial prefrontal cortex, dentate gyrus, and CA3 might be implicated in this sustained antidepressant effect. PMID:27765808

Investigation of antidepressant-like and anxiolytic-like actions and cognitive and motor side effects of four N-methyl-D-aspartate receptor antagonists in mice.

PubMed

Refsgaard, Louise K; Pickering, Darryl S; Andreasen, Jesper T

2017-02-01

Evidence suggests that N-methyl-D-aspartate receptor (NMDAR) antagonists could be efficacious in treating depression and anxiety, but side effects constitute a challenge. This study evaluated the antidepressant-like and anxiolytic-like actions, and cognitive and motor side effects of four NMDAR antagonists. MK-801, ketamine, S-ketamine, RO 25-6981 and the positive control, citalopram, were tested for antidepressant-like and anxiolytic-like effects in mice using the forced-swim test, the elevated zero maze and the novelty-induced hypophagia test. Side effects were assessed using a locomotor activity test, the modified Y-maze and the rotarod test. All compounds increased swim distance in the forced-swim test. In the elevated zero maze, the GluN2B subtype-selective RO 25-6981 affected none of the measured parameters, whereas all other compounds showed anxiolytic-like effects. In the novelty-induced hypophagia test, citalopram and MK-801 showed anxiogenic-like action. All NMDAR antagonists induced hyperactivity. The high doses of ketamine and MK-801 impaired performance in the modified Y-maze test, whereas S-ketamine and RO 25-6891 showed no effects in this test. Only MK-801 impaired rotarod performance. The study supports that NMDARs could be a possible therapeutic target for treating depression and anxiety. However, selective antagonism of GluN2B subunit-containing NMDARs showed no effect on anxiety-like behaviours in this study.

In vitro effects of oxytocin, acepromazine, detomidine, xylazine, butorphanol, terbutaline, isoproterenol, and dantrolene on smooth and skeletal muscles of the equine esophagus.

PubMed

Wooldridge, Anne A; Eades, Susan C; Hosgood, Giselle L; Moore, Rustin M

2002-12-01

To characterize the in vitro effects of oxytocin, acepromazine, xylazine, butorphanol, detomidine, dantrolene, isoproterenol, and terbutaline on skeletal and smooth muscle from the equine esophagus. 14 adult horses without digestive tract disease. Circular and longitudinal strips from the skeletal and smooth muscle of the esophagus were suspended in tissue baths, connected to force-displacement transducers interfaced with a physiograph, and electrical field stimulation was applied. Cumulative concentration-response curves were generated for oxytocin, acepromazine, xylazine, detomidine, butorphanol, isoproterenol, terbutaline, and dantrolene. Mean maximum twitch amplitude for 3 contractions/min was recorded and compared with predrug-vehicle values for the skeletal muscle segments, and area under the curve (AUC) for 3 contractions/min was compared with predrug-vehicle values for the smooth muscle segments. No drugs caused a significant change in skeletal muscle response. In smooth muscle, isoproterenol, terbutaline, and oxytocin significantly reduced AUC in a concentration-dependent manner. Maximum reduction in AUC was 69% at 10(-4) M for isoproterenol, 63% at 10(-6) M for terbutaline, and 64% at 10(-4) M for oxytocin. Isoproterenol, terbutaline, and oxytocin cause relaxation of the smooth muscle portion of the esophagus. The clinical relaxant effects on the proximal portion of the esophagus reported of drugs such as oxytocin, detomidine, and acepromazine may be the result of centrally mediated mechanisms.

Ketamine metabolites with antidepressant effects: Fast, economical, and eco-friendly enantioselective separation based on supercritical-fluid chromatography (SFC) and single quadrupole MS detection.

PubMed

Fassauer, Georg M; Hofstetter, Robert; Hasan, Mahmoud; Oswald, Stefan; Modeß, Christina; Siegmund, Werner; Link, Andreas

2017-11-30

Increasing evidence accumulates that metabolites of the dissociative anesthetic ketamine contribute considerably to the biological effects of this drug and could be developed as next generation antidepressants, especially for acute treatment of patients with therapy-refractory major depression. Analytical methods for the simultaneous determination of the plethora of hydroxylated, dehydrogenated and/or demethylated compounds formed after administration of ketamine hydrochloride are a prerequisite for future clinical investigations and a deeper understanding of the individual role of the isomers of these metabolites. In this study, we present development and validation of a method based on supercritical-fluid chromatography (SFC) coupled to single quadrupole MS detection that allows the separation of ketamine as well as all of its relevant metabolites detected in urine of healthy volunteers. Inherently to SFC methods, the run times of the novel protocol are four times shorter than in a comparable HPLC method, the use of organic solvents is reduced and we were able to demonstrate and validate the successful enantioselective separation and quantification of R- and S-ketamine, R- and S-norketamine, R- and S-dehydronorketamine and (2R,6R)- and (2S,6S)-hydroxynorketamine isomers differing in either constitution, stereochemistry, or both, in one run. The developed method may be useful in investigating the antidepressant efficacy of ketamine in clinical trials. Copyright © 2017 Elsevier B.V. All rights reserved.

Topical Ketamine 10% for Neuropathic Pain in Spinal Cord Injury Patients: An Open-Label Trial.

PubMed

Rabi, Joseph; Minori, Joshua; Abad, Hasan; Lee, Ray; Gittler, Michelle

2016-01-01

Topical ketamine, an N-methyl-D-aspartate antagonist, has been shown to be effective in certain neuropathic pain syndromes. The objective of this study was to determine the efficacy of topical ketamine in spinal cord injury patients with neuropathic pain. An open label trial enrolled five subjects at an outpatient rehabilitation hospital with traumatic spinal cord injuries who had neuropathic pain at or below the level of injury. Subjects applied topical ketamine 10% three times a day for a two-week duration. Subjects recorded their numerical pain score-ranging from 0 to 10, with 0 representing "no pain, 5 representing "moderate pain," and 10 being described as "worst possible pain"-in a journal at the time of application of topical ketamine and one hour after application. Using a numerical pain scale allows for something as subjective as pain to be given an objective quantification. Subjects also recorded any occurrence of adverse events and level of satisfaction. All five subjects had a decrease in their numerical pain scale by the end of two weeks, ranging from 14% to 63%. The duration ranged from one hour in one subject to the next application in other subjects. There were no adverse effects. Overall, four out of the five subjects stated they were satisfied. Topical ketamine 10% is an effective neuropathic pain medicine in patients with spinal cord injuries; however, further studies need to be done with a placebo and larger sample size. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

Effects of acepromazine and trazodone on anesthetic induction dose of propofol and cardiovascular variables in dogs undergoing general anesthesia for orthopedic surgery.

PubMed

Murphy, Lindsey A; Barletta, Michele; Graham, Lynelle F; Reichl, Lorna J; Duxbury, Margaret M; Quandt, Jane E

2017-02-15

OBJECTIVE To compare the doses of propofol required to induce general anesthesia in dogs premedicated with acepromazine maleate or trazodone hydrochloride and compare the effects of these premedicants on cardiovascular variables in dogs anesthetized for orthopedic surgery. DESIGN Prospective, randomized study. ANIMALS 30 systemically healthy client-owned dogs. PROCEDURES 15 dogs received acepromazine (0.01 to 0.03 mg/kg [0.005 to 0.014 mg/lb], IM) 30 minutes before anesthetic induction and 15 received trazodone (5 mg/kg [2.27 mg/lb] for patients > 10 kg or 7 mg/kg [3.18 mg/lb] for patients ≤ 10 kg, PO) 2 hours before induction. Both groups received morphine sulfate (1 mg/kg [0.45 mg/lb], IM) 30 minutes before induction. Anesthesia was induced with propofol (4 to 6 mg/kg [1.82 to 2.73 mg/lb], IV, to effect) and maintained with isoflurane or sevoflurane in oxygen. Bupivacaine (0.5 mg/kg [0.227 mg/lb]) and morphine (0.1 mg/kg [0.045 mg/lb]) were administered epidurally. Dogs underwent tibial plateau leveling osteotomy (n = 22) or tibial tuberosity advancement (8) and were monitored throughout anesthesia. Propofol induction doses and cardiovascular variables (heart rate and systemic, mean, and diastolic arterial blood pressures) were compared between groups. RESULTS The mean dose of propofol required for anesthetic induction and all cardiovascular variables evaluated did not differ between groups. Intraoperative hypotension developed in 6 and 5 dogs of the acepromazine and trazodone groups, respectively; bradycardia requiring intervention developed in 3 dogs/group. One dog that received trazodone had priapism 24 hours later and was treated successfully. No other adverse effects were reported. CONCLUSIONS AND CLINICAL RELEVANCE At the described dosages, cardiovascular effects of trazodone were similar to those of acepromazine in healthy dogs undergoing anesthesia for orthopedic surgery.

Comparison of sedation and mechanical antinociception induced by intravenous administration of acepromazine and four dose rates of dexmedetomidine in donkeys.

PubMed

Lizarraga, Ignacio; Castillo-Alcala, Fernanda; Robinson, Lauren S

2017-05-01

To assess and compare the sedative and antinociceptive effects of four dosages of dexmedetomidine in donkeys. Randomized, controlled, crossover, Latin-square, blinded study. Six healthy, castrated, adult, standard donkeys. Dexmedetomidine (2, 3, 4 and 5 μg kg -1 ; D2, D3, D4 and D5), acepromazine (0.1 mg kg -1 ) and saline were administered intravenously to each donkey and a 1 week interval was allowed between successive trials on each animal. Sedation scores (SS) and head heights above ground (HHAG) were used to assess sedation and mechanical nociceptive threshold (MNT) testing to assess antinociception over 120 minutes post-treatment. Areas under the curve (AUC) for 0-30, 30-60 and 60-120 minutes were computed to compare the effect of treatments. SS-AUC 0-30 values were larger for D4 and D5, and SS-AUC 30-60 values were larger for D5 than for saline. All dexmedetomidine treatments produced lower HHAG-AUC 0-30 and HHAG-AUC 30-60 values, and acepromazine produced lower HHAG AUC 60-120 values than did saline. For MNT, D3, D4 and D5 increased AUC 0-30 and AUC 30-60 values compared with saline and also AUC 0-30 values compared with D2 and acepromazine. Smaller MNT-AUC 30-60 values were obtained with D2 than with D4 and D5, with D3 than with D5, and with acepromazine than with D4 and D5. Dexmedetomidine induced sedation and dosage-dependent mechanical antinociception. Larger dexmedetomidine dose rates were required to induce antinociception than sedation. Furthermore, the antinociception induced by dexmedetomidine was of shorter duration than its sedation. For minor painful procedures on standing donkeys, D5 may be clinically useful to provide sedation and analgesia. Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

The effects of detomidine, romifidine or acepromazine on echocardiographic measurements and cardiac function in normal horses.

PubMed

Buhl, Rikke; Ersbøll, Annette K; Larsen, Nanna H; Eriksen, Lis; Koch, Jørgen

2007-01-01

To evaluate by echo- and electrocardiography the cardiac effects of sedation with detomidine hydrochloride, romifidine hydrochloride or acepromazine maleate in horses. An experimental study using a cross-over design without randomization. Eight clinically normal Standardbred trotters. Echocardiographic examinations (two-dimensional, guided M-mode and colour Doppler) were recorded on five different days. Heart rate (HR) and standard limb lead electrocardiograms were also obtained. Subsequently, horses were sedated with detomidine (0.01 mg kg(-1)), romifidine (0.04 mg kg(-1)) or acepromazine (0.1 mg kg(-1)) administered intravenously and all examinations repeated. Heart rate before treatment with the three drugs did not differ significantly (p = 0.98). Both detomidine and romifidine induced a significant decrease (p < 0.001) in HR during the first 25 minutes after sedation; while acepromazine had a varying effect on HR. For detomidine, there was a significant increase in LVIDd (left ventricular internal diameter in diastole; p = 0.034) and LVIDs (left ventricular internal diameter in systole; p < 0.001). In addition, a significant decrease was found in IVSs (the interventricular septum in systole; p < 0.001), LVFWs (the left ventricular free wall in systole; p = 0.002) and FS% (fractional shortening; p < 0.001). The frequency of pulmonary regurgitation was increased significantly (p < 0.001). Romifidine induced a significant increase in LVIDs (p < 0.001) and a significant decrease in IVSs (p < 0.001) and FS% (p = 0.002). Acepromazine had no significant effect upon any of the measured values. and clinical relevance The results indicate that sedation of horses with detomidine and to a lesser extent romifidine at the doses given in this study has a significant effect on heart function, echocardiographic measurements of heart dimensions and the occurrence of valvular regurgitation. Although the clinical significance of these results may be minimal, the potential effects of sedative drugs should be taken into account when echocardiographic variables are interpreted in clinical cases.

Sedation with detomidine and acepromazine influences the endoscopic evaluation of laryngeal function in horses.

PubMed

Lindegaard, C; Husted, L; Ullum, H; Fjeldborg, J

2007-11-01

Endoscopy of the upper airways of horses is used as a diagnostic tool and at purchase examinations. On some occasions it is necessary to use sedation during the procedure and it is often speculated that the result of the examination might be influenced due to the muscle-relaxing properties of the most commonly used sedatives. To evaluate the effect of detomidine (0.01 mg/kg bwt) and acepromazine (0.05 mg/kg bwt) on the appearance of symmetry of rima glottidis, ability to abduct maximally the arytenoid cartilages and the effect on recurrent laryngeal neuropathy (RLN) grade. Forty-two apparently normal horses underwent endoscopic examination of the upper airways on 3 different occasions, under the influence of 3 different treatments: no sedation (control), sedation with detomidine and sedation with acepromazine. All examinations were performed with a minimum of one week apart. The study was performed as an observer-blind cross-over study. Sedation with detomidine had a significant effect on the RLN grading (OR = 2.91) and ability maximally to abduct the left arytenoid cartilages (OR = 2.91). Sedation with acepromazine resulted in OR = 2.43 for the RLN grading and OR = 2.22 for the ability to abduct maximally. The ability to abduct maximally the right arytenoid cartilage was not altered. Sedating apparently healthy horses with detomidine or acepromazine significantly impairs these horses' ability to abduct fully the left but not the right arytenoid cartilage. This resulted in different diagnosis with respect to RLN when comparing sedation to no sedation. Since the ability to abduct the right arytenoid cartilage fully is not altered by sedation, it is speculated that horses changing from normal to abnormal laryngeal function when sedated, might be horses in an early stage of the disease. To confirm or reject these speculations, further studies are needed. Until then sedation during endoscopy should be used with care.

Acute encephalopathy with concurrent respiratory and metabolic disturbances in first known parenteral human administration of flunixin meglumine and acepromazine maleate.

PubMed

Kamali, Michael F; Wilson, Anwar C; Acquisto, Nicole M; Spillane, Linda; Schneider, Sandra M

2013-08-01

Flunexin is a nonsteroidal anti-inflammatory drug approved for veterinary use in horses and cattle. Acepromazine is a phenothiazine derivative used in horses, dogs, and cats. Human exposure to these substances is rare. We report a case of a human injection of two equine medications, flunixin and acepromazine, which resulted in altered mental status, respiratory alkalosis, gastrointestinal bleeding, and elevation of liver transaminases in a 43-year-old woman who worked as a horse trainer. The patient intentionally self-injected these medications and subsequently presented to the Emergency Department with altered mental status and lethargy. The patient required hospitalization for metabolic abnormalities, including respiratory alkalosis, and suffered a gastrointestinal bleed requiring blood transfusion. The patient ultimately recovered with supportive measures. We believe this to be the first case of concomitant injection of flunixin and acepromazine in a human. This report explains a case of parenteral administration of two equine medications and the subsequent complications in a patient that presented to the Emergency Department. Human exposure to veterinary medications cannot be predicted by their effect in animals due to variations in absorption, distribution, and metabolism. Physicians should be aware that individuals who work with animals may have access to large quantities of veterinary medicine. This case also exemplifies the challenges that Emergency Physicians face on a daily basis, and generates additional consideration for overdoses and intoxications from medications that are not considered commonplace in humans. Copyright © 2013 Elsevier Inc. All rights reserved.

Memantine and Ketamine Differentially Alter NMDA Receptor Desensitization

PubMed Central

Povysheva, Nadezhda V.; Azofeifa, Andrea M.

2017-01-01

Memantine and ketamine are clinically useful NMDA receptor (NMDAR) open channel blockers that inhibit NMDARs with similar potency and kinetics, but display vastly different clinical profiles. This discrepancy has been hypothesized to result from inhibition by memantine and ketamine of overlapping but distinct NMDAR subpopulations. For example, memantine but not ketamine may inhibit extrasynaptic NMDARs more effectively than synaptic NMDARs. However, the basis for preferential NMDAR inhibition depending on subcellular location has not been investigated systematically. We integrated recordings from heterologously expressed single NMDAR subtypes, kinetic modeling, and recordings of synaptically evoked NMDAR responses in acute brain slices to investigate mechanisms by which channel blockers may distinguish NMDAR subpopulations. We found that memantine and ketamine differentially alter NMDAR desensitization and that memantine stabilizes a Ca2+-dependent desensitized state. As a result, inhibition by memantine of GluN1/2A receptors in tsA201 cells and of native synaptic NMDARs in cortical pyramidal neurons from mice of either sex increased in conditions that enhanced intracellular Ca2+ accumulation. Therefore, differential inhibition by memantine and ketamine based on NMDAR location is likely to result from location dependence of the intensity and duration of NMDAR activation. Modulation of Ca2+-dependent NMDAR desensitization is an unexplored mechanism of inhibitory action with the potential to endow drugs with NMDAR selectivity that leads to superior clinical profiles. Our results suggest that designing compounds to target specific receptor states, rather than specific receptor types, may be a viable strategy for future drug development. SIGNIFICANCE STATEMENT Memantine and ketamine are NMDA receptor (NMDAR) channel-blocking drugs with divergent clinical effects. Understanding mechanistically their differential actions may advance our understanding of nervous system disorders and suggest strategies for the design of more effective drugs. Here, we show that memantine and ketamine have contrasting effects on NMDAR desensitization. Ketamine binding decreases occupancy of desensitized states of the GluN1/2B NMDAR subtype. In contrast, memantine binding increases occupancy of GluN1/2A and native NMDAR desensitized states entered after accumulation of intracellular Ca2+, a novel inhibitory mechanism. These properties may contribute to inhibition of distinct NMDAR subpopulations by memantine and ketamine and help to explain their differential clinical effects. Our results suggest stabilization of Ca2+-dependent desensitized states as a new strategy for pharmaceutical neuroprotection. PMID:28877967

Memantine and Ketamine Differentially Alter NMDA Receptor Desensitization.

PubMed

Glasgow, Nathan G; Povysheva, Nadezhda V; Azofeifa, Andrea M; Johnson, Jon W

2017-10-04

Memantine and ketamine are clinically useful NMDA receptor (NMDAR) open channel blockers that inhibit NMDARs with similar potency and kinetics, but display vastly different clinical profiles. This discrepancy has been hypothesized to result from inhibition by memantine and ketamine of overlapping but distinct NMDAR subpopulations. For example, memantine but not ketamine may inhibit extrasynaptic NMDARs more effectively than synaptic NMDARs. However, the basis for preferential NMDAR inhibition depending on subcellular location has not been investigated systematically. We integrated recordings from heterologously expressed single NMDAR subtypes, kinetic modeling, and recordings of synaptically evoked NMDAR responses in acute brain slices to investigate mechanisms by which channel blockers may distinguish NMDAR subpopulations. We found that memantine and ketamine differentially alter NMDAR desensitization and that memantine stabilizes a Ca 2+ -dependent desensitized state. As a result, inhibition by memantine of GluN1/2A receptors in tsA201 cells and of native synaptic NMDARs in cortical pyramidal neurons from mice of either sex increased in conditions that enhanced intracellular Ca 2+ accumulation. Therefore, differential inhibition by memantine and ketamine based on NMDAR location is likely to result from location dependence of the intensity and duration of NMDAR activation. Modulation of Ca 2+ -dependent NMDAR desensitization is an unexplored mechanism of inhibitory action with the potential to endow drugs with NMDAR selectivity that leads to superior clinical profiles. Our results suggest that designing compounds to target specific receptor states, rather than specific receptor types, may be a viable strategy for future drug development. SIGNIFICANCE STATEMENT Memantine and ketamine are NMDA receptor (NMDAR) channel-blocking drugs with divergent clinical effects. Understanding mechanistically their differential actions may advance our understanding of nervous system disorders and suggest strategies for the design of more effective drugs. Here, we show that memantine and ketamine have contrasting effects on NMDAR desensitization. Ketamine binding decreases occupancy of desensitized states of the GluN1/2B NMDAR subtype. In contrast, memantine binding increases occupancy of GluN1/2A and native NMDAR desensitized states entered after accumulation of intracellular Ca 2+ , a novel inhibitory mechanism. These properties may contribute to inhibition of distinct NMDAR subpopulations by memantine and ketamine and help to explain their differential clinical effects. Our results suggest stabilization of Ca 2+ -dependent desensitized states as a new strategy for pharmaceutical neuroprotection. Copyright © 2017 the authors 0270-6474/17/379686-19$15.00/0.

Effects of ketamine, propofol, or thiopental administration on intraocular pressure and qualities of induction of and recovery from anesthesia in horses.

PubMed

Ferreira, Tatiana H; Brosnan, Robert J; Shilo-Benjamini, Yael; Moore, Stephanie B; Hollingsworth, Steven R

2013-08-01

To assess the effects of ketamine hydrochloride, propofol, or compounded thiopental sodium administration on intraocular pressure (IOP) and qualities of induction of and recovery from anesthesia in horses. 6 healthy adult horses. Horses were sedated with xylazine hydrochloride (0.5 mg/kg), and anesthesia was induced with guaifenesin followed by ketamine (2 mg/kg), propofol (3 mg/kg), or thiopental (4 mg/kg) in a crossover study with ≥ 1 week between treatments. For each horse, IOP in the right eye was measured with a handheld applanation tonometer before and after xylazine administration, at the time of recumbency, and every 3 minutes after induction of anesthesia until spontaneous movement was observed. Cardiorespiratory responses and venous blood measurements were recorded during anesthesia. Induction of and recovery from anesthesia were subjectively evaluated by investigators who were unaware of the anesthetic treatment of each horse. Data were analyzed via a repeated-measures ANOVA with Holm-Ŝidák post hoc comparisons. Compared with findings after xylazine administration (mean ± SD, 17 ± 3 mm Hg), thiopental decreased IOP by 4 ± 23%, whereas propofol and ketamine increased IOP by 8 ± 11% and 37 ± 16%, respectively. Compared with the effects of ketamine, propofol and thiopental resulted in significantly lower IOP at the time of recumbency and higher heart rates at 3 minutes after induction of anesthesia. No other significant differences among treatments were found. These findings support the use of thiopental or propofol in preference to ketamine for horses in which increases in IOP should be minimized.

Behavioral, endocrine, and neuronal alterations in zebrafish (Danio rerio) following sub-chronic coadministration of fluoxetine and ketamine.

PubMed

Pittman, Julian; Hylton, Andrew

2015-12-01

Most existing pharmacological treatments have focused on the "monoamine hypothesis" for targeted drug design for major depressive disorder (MDD). Many of these medications have a delayed onset-of-action and limited efficacy. Antidepressants with principal targets outside the monoamine system may offer the potential for more rapid activity with improved therapeutic benefit. Growing evidence suggests that the glutamatergic system is uniquely central to the neurobiology and treatment of MDD. Ketamine (Ketalar®) is a non-competitive glutamatergic antagonist classically used to induce sedation. However, preliminary clinical evidence has been promising with regard to its rapidly acting antidepressant profile. Zebrafish (Danio rerio) have emerged as a promising new animal model to screen the effects of numerous psychotropic compounds. This study aimed to determine if a sub-chronic low (sub-anesthetic) dose of ketamine could be used to augment the antidepressant effects of the widely used antidepressant fluoxetine (Prozac®) in adult zebrafish, employing an ethanol withdrawal model. Sub-chronic exposure to dosages of 100μg/L fluoxetine and 20mg/L of ketamine reduced anxiety/depression-like behaviors, leads to upregulation of serotonin synthesis and elevated whole-body cortisol levels. These results demonstrate the utility of zebrafish as a model for neuropharmacological research, and the possible efficacy of fluoxetine and ketamine coadministration. Copyright © 2015 Elsevier Inc. All rights reserved.

Indistinguishable Synaptic Pharmacodynamics of the N-Methyl-d-Aspartate Receptor Channel Blockers Memantine and Ketamine

PubMed Central

Emnett, Christine M.; Eisenman, Lawrence N.; Taylor, Amanda M.; Izumi, Yukitoshi; Zorumski, Charles F.

2013-01-01

Memantine and ketamine, voltage- and activation-dependent channel blockers of N-methyl-d-aspartate (NMDA) receptors (NMDARs), have enjoyed a recent resurgence in clinical interest. Steady-state pharmacodynamic differences between these blockers have been reported, but it is unclear whether the compounds differentially affect dynamic physiologic signaling. In this study, we explored nonequilibrium conditions relevant to synaptic transmission in hippocampal networks in dissociated culture and hippocampal slices. Equimolar memantine and ketamine had indistinguishable effects on the following measures: steady-state NMDA currents, NMDAR excitatory postsynaptic current (EPSC) decay kinetics, progressive EPSC inhibition during repetitive stimulation, and extrasynaptic NMDAR inhibition. Therapeutic drug efficacy and tolerability of memantine have been attributed to fast kinetics and strong voltage dependence. However, pulse depolarization in drug presence revealed a surprisingly slow and similar time course of equilibration for the two compounds, although memantine produced a more prominent fast component (62% versus 48%) of re-equilibration. Simulations predicted that low gating efficacy underlies the slow voltage–dependent relief from block. This prediction was empirically supported by faster voltage-dependent blocker re-equilibration with several experimental manipulations of gating efficacy. Excitatory postsynaptic potential–like voltage commands produced drug differences only with large, prolonged depolarizations unlikely to be attained physiologically. In fact, we found no difference between drugs on measures of spontaneous network activity or acute effects on plasticity in hippocampal slices. Despite indistinguishable synaptic pharmacodynamics, ketamine provided significantly greater neuroprotection from damage induced by oxygen glucose deprivation, consistent with the idea that under extreme depolarizing conditions, the biophysical difference between drugs becomes detectable. We conclude that despite subtle differences in voltage dependence, during physiologic activity, blocker pharmacodynamics are largely indistinguishable and largely voltage independent. PMID:24101301

Imaging the neuroplastic effects of ketamine with VBM and the necessity of placebo control.

PubMed

Höflich, A; Ganger, S; Tik, M; Hahn, A; Kranz, G S; Vanicek, T; Spies, M; Kraus, C; Windischberger, C; Kasper, S; Winkler, D; Lanzenberger, R

2017-02-15

In the last years a plethora of studies have investigated morphological changes induced by behavioural or pharmacological interventions using structural T1-weighted MRI and voxel-based morphometry (VBM). Ketamine is thought to exert its antidepressant action by restoring neuroplasticity. In order to test for acute impact of a single ketamine infusion on grey matter volume we performed a placebo-controlled, double-blind investigation in healthy volunteers using VBM. 28 healthy individuals underwent two MRI sessions within a timeframe of 2 weeks, each consisting of two structural T1-weighted MRIs within a single session, one before and one 45min after infusion of S-ketamine (bolus of 0.11mg/kg, followed by an maintenance infusion of 0.12mg/kg) or placebo (0.9% NaCl infusion) using a crossover design. In the repeated-measures ANOVA with time (post-infusion/pre-infusion) and medication (placebo/ketamine) as factors, no significant effect of interaction and no effect of medication was found (FWE-corrected). Importantly, further post-hoc t-tests revealed a strong "decrease" of grey matter both in the placebo and the ketamine condition over time. This effect was evident mainly in frontal and temporal regions bilaterally with t-values ranging from 4.95 to 5.31 (FWE-corrected at p<0.05 voxel level). The vulnerabilities of VBM have been repeatedly demonstrated, with reports of influence of blood flow, tissue water and direct effects of pharmacological compounds on the MRI signal. Here again, we highlight that the relationship between intervention and VBM results is apparently subject to a number of physiological influences, which are partly unknown. Future studies focusing on the effects of ketamine on grey matter should try to integrate known influential factors such as blood flow into analysis. Furthermore, the results of this study highlight the importance of a carefully performed placebo condition in pharmacological fMRI studies. Copyright © 2016 Elsevier Inc. All rights reserved.

A Negative Allosteric Modulator for α5 Subunit-Containing GABA Receptors Exerts a Rapid and Persistent Antidepressant-Like Action without the Side Effects of the NMDA Receptor Antagonist Ketamine in Mice

PubMed Central

Nelson, Mackenzie E.; Krimmel, Samuel R.; Georgiou, Polymnia; Gould, Todd D.

2017-01-01

Abstract New antidepressant pharmacotherapies that provide rapid relief of depressive symptoms are needed. The NMDA receptor antagonist ketamine exerts rapid antidepressant actions in depressed patients but also side effects that complicate its clinical utility. Ketamine promotes excitatory synaptic strength, likely by producing high-frequency correlated activity in mood-relevant regions of the forebrain. Negative allosteric modulators of GABA-A receptors containing α5 subunits (α5 GABA-NAMs) should also promote high-frequency correlated electroencephalogram (EEG) activity and should therefore exert rapid antidepressant responses. Because α5 subunits display a restricted expression in the forebrain, we predicted that α5 GABA-NAMs would produce activation of principle neurons but exert fewer side effects than ketamine. We tested this hypothesis in male mice and observed that the α5 GABA-NAM MRK-016 exerted an antidepressant-like response in the forced swim test at 1 and 24 h after administration and an anti-anhedonic response after chronic stress in the female urine sniffing test (FUST). Like ketamine, MRK-016 produced a transient increase in EEG γ power, and both the increase in γ power and its antidepressant effects in the forced swim test were blocked by prior administration of the AMPA-type glutamate receptor antagonist 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide (NBQX). Unlike ketamine, however, MRK-016 produced no impairment of rota-rod performance, no reduction of prepulse inhibition (PPI), no conditioned-place preference (CPP), and no change in locomotion. α5 GABA-NAMs, thus reproduce the rapid antidepressant-like actions of ketamine, perhaps via an AMPA receptor (AMPAR)-dependent increase in coherent neuronal activity, but display fewer potential negative side effects. These compounds thus demonstrate promise as clinically useful fast-acting antidepressants. PMID:28275719

Comparing the actions of lanicemine and ketamine in depression: key role of the anterior cingulate.

PubMed

Downey, Darragh; Dutta, Arpan; McKie, Shane; Dawson, Gerard R; Dourish, Colin T; Craig, Kevin; Smith, Mark A; McCarthy, Dennis J; Harmer, Catherine J; Goodwin, Guy M; Williams, Steve; Deakin, J F William

2016-06-01

Intravenous infusion of lanicemine (formerly AZD6765), a low trapping non-selective N-methyl-D-aspartate (NMDA) receptor antagonist, induces antidepressant effects with a similar time course to ketamine. We investigated whether a single dose lanicemine infusion would reproduce the previously reported decrease in subgenual anterior cingulate cortex (sgACC) activity evoked by ketamine, a potential mechanism of antidepressant efficacy. Sixty un-medicated adults meeting the criteria for major depressive disorder were randomly assigned to receive constant intravenous infusions of ketamine, lanicemine or saline during a 60min pharmacological magnetic resonance imaging (phMRI) scan. Both ketamine and lanicemine gradually increased the blood oxygen level dependent signal in sgACC and rostral ACC as the primary outcome measure. No decreases in signal were seen in any region. Interviewer-rated psychotic and dissociative symptoms were minimal following administration of lanicemine. There was no significant antidepressant effect of either infusion compared to saline. The previously reported deactivation of sgACC after ketamine probably reflects the rapid and pronounced subjective effects evoked by the bolus-infusion method used in the previous study. Activation of the ACC was observed following two different NMDA compounds in both Manchester and Oxford using different 3T MRI scanners, and this effect predicted improvement in mood 1 and 7 days post-infusion. These findings suggest that the initial site of antidepressant action for NMDA antagonists may be the ACC (NCT01046630. A Phase I, Multi-centre, Double-blind, Placebo-controlled Parallel Group Study to Assess the pharmacoMRI Effects of AZD6765 in Male and Female Subjects Fulfilling the Criteria for Major Depressive Disorder; http://clinicaltrials.gov/show/NCT01046630). Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

Chronic Ketamine Reduces the Peak Frequency of Gamma Oscillations in Mouse Prefrontal Cortex Ex vivo.

PubMed

McNally, James M; McCarley, Robert W; Brown, Ritchie E

2013-01-01

Abnormalities in EEG gamma band oscillations (GBO, 30-80 Hz) serve as a prominent biomarker of schizophrenia (Sz), associated with positive, negative, and cognitive symptoms. Chronic, subanesthetic administration of antagonists of N-methyl-D-aspartate receptors (NMDAR), such as ketamine, elicits behavioral effects, and alterations in cortical interneurons similar to those observed in Sz. However, the chronic effects of ketamine on neocortical GBO are unknown. Thus, here we examine the effects of chronic (five daily i.p. injections) application of ketamine (5 and 30 mg/kg) and the more specific NMDAR antagonist, MK-801 (0.02, 0.5, and 2 mg/kg), on neocortical GBO ex vivo. Oscillations were generated by focal application of the glutamate receptor agonist, kainate (KA), in coronal brain slices containing the prelimbic cortex. This region constitutes the rodent analog of the human dorsolateral prefrontal cortex, a brain region strongly implicated in Sz-pathophysiology. Here we report the novel finding that chronic ketamine elicits a reduction in the peak oscillatory frequency of KA-elicited oscillations (from 47 to 40 Hz at 30 mg/kg). Moreover, the power of GBO in the 40-50 Hz band was reduced. These findings are reminiscent of both the reduced resonance frequency and power of cortical oscillations observed in Sz clinical studies. Surprisingly, MK-801 had no significant effect, suggesting care is needed when equating Sz-like behavioral effects elicited by different NMDAR antagonists to alterations in GBO activity. We conclude that chronic ketamine in the mouse mimics GBO abnormalities observed in Sz patients. Use of this ex vivo slice model may be useful in testing therapeutic compounds which rescue these GBO abnormalities.

Ketamine Suppresses the Ventral Striatal Response to Reward Anticipation: A Cross-Species Translational Neuroimaging Study

PubMed Central

Francois, Jennifer; Grimm, Oliver; Schwarz, Adam J; Schweiger, Janina; Haller, Leila; Risterucci, Celine; Böhringer, Andreas; Zang, Zhenxiang; Tost, Heike; Gilmour, Gary; Meyer-Lindenberg, Andreas

2016-01-01

Convergent evidence implicates regional neural responses to reward anticipation in the pathogenesis of several psychiatric disorders, such as schizophrenia, where blunted ventral striatal responses to positive reward are observed in patients and at-risk populations. In vivo oxygen amperometry measurements in the ventral striatum in awake, behaving rats reveal reward-related tissue oxygen changes that closely parallel blood oxygen level dependent (BOLD) signal changes observed in human functional magnetic resonance imaging (fMRI), suggesting that a cross-species approach targeting this mechanism might be feasible in psychopharmacology. The present study explored modulatory effects of acute, subanaesthetic doses of ketamine—a pharmacological model widely used in psychopharmacological research, both preclinically and clinically—on ventral striatum activity during performance of a reward anticipation task in both species, using fMRI in humans and in vivo oxygen amperometry in rats. In a region-of-interest analysis conducted following a cross-over placebo and ketamine study in human subjects, an attenuated ventral striatal response during reward anticipation was observed following ketamine relative to placebo during performance of a monetary incentive delay task. In rats, a comparable attenuation of ventral striatal signal was found after ketamine challenge, relative to vehicle, in response to a conditioned stimulus that predicted delivery of reward. This study provides the first data in both species demonstrating an attenuating effect of acute ketamine on reward-related ventral striatal (O2) and fMRI signals. These findings may help elucidate a deeper mechanistic understanding of the potential role of ketamine as a model for psychosis, show that cross-species pharmacological experiments targeting reward signaling are feasible, and suggest this phenotype as a promising translational biomarker for the development of novel compounds, assessment of disease status, and treatment efficacy. PMID:26388147

Molecular and Cellular Mechanisms of Rapid-Acting Antidepressants Ketamine and Scopolamine

PubMed Central

Wohleb, Eric S.; Gerhard, Danielle; Thomas, Alex; Duman, Ronald S.

2017-01-01

Major depressive disorder (MDD) is a prevalent neuropsychiatric disease that causes profound social and economic burdens. The impact of MDD is compounded by the limited therapeutic efficacy and delay of weeks to months of currently available medications. These issues highlight the need for more efficacious and faster-acting treatments to alleviate the burdens of MDD. Recent breakthroughs demonstrate that certain drugs, including ketamine and scopolamine, produce rapid and long-lasting antidepressant effects in MDD patients. Moreover, preclinical work has shown that the antidepressant actions of ketamine and scopolamine in rodent models are caused by an increase of extracellular glutamate, elevated BDNF, activation of the mammalian target of rapamycin complex 1 (mTORC1) cascade, and increased number and function of spine synapses in the prefrontal cortex (PFC). Here we review studies showing that both ketamine and scopolamine elicit rapid antidepressant effects through converging molecular and cellular mechanisms in the PFC. In addition, we discuss evidence that selective antagonists of NMDA and muscarinic acetylcholine (mACh) receptor subtypes (i.e., NR2B and M1-AChR) in the PFC produce comparable antidepressant responses. Furthermore, we discuss evidence that ketamine and scopolamine antagonize inhibitory interneurons in the PFC leading to disinhibition of pyramidal neurons and increased extracellular glutamate that promotes the rapid antidepressant responses to these agents. Collectively, these studies indicate that specific NMDA and mACh receptor subtypes on GABAergic interneurons are promising targets for novel rapid-acting antidepressant therapies. PMID:26955968

Cardiopulmonary effects during anaesthesia induced and maintained with propofol in acepromazine pre-medicated donkeys.

PubMed

Naddaf, Hadi; Baniadam, Ali; Rasekh, Abdolrahman; Arasteh, Abdolmajid; Sabiza, Soroush

2015-01-01

To evaluate the cardiopulmonary effects of anaesthesia induced and maintained with propofol in acepromazine pre-medicated donkeys. Prospective experimental study. Six healthy male donkeys weighing 78-144 kg. Donkeys were pre-medicated with intravenous (IV) acepromazine (0.04 mg kg(-1) ). Ten minutes later, anaesthesia was induced with IV propofol (2 mg kg(-1) ) and anaesthesia maintained by continuous IV infusion of the propofol (0.2 mg kg(-1)  minute(-1) ) for 30 minutes. Baseline measurements of physiological parameters, and arterial blood samples were taken before the acepromazine administration, then 5, 15, 30, 45, and 60 minutes after the induction of anaesthesia. Changes from baseline were analysed by anova for repeated measures. When compared with baseline (standing) values, during anaesthesia heart rate increased throughout: significant at 5 (p = 0.001) and 15 (p = 0.015) minutes. Mean arterial blood pressure increased significantly only at 15 minutes (p < 0.001). Respiratory rate and arterial pH did not change significantly. PaO2 was lower throughout anaethesia, but this only reached significance at 15 minutes (p = 0.041). PaCO2 was statistically (but not clinically) significantly reduced at the times of 30 (p = 0.02), 45 (p = 0.01) and 60 (p = 0.04). Rectal temperature decreased significantly at all times of the study. Administration of propofol by the continuous infusion rate for the maintenance of anaesthesia resulted in stable cardiopulmonary effects and could prove to be clinically useful in donkeys. © 2014 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

Antinociceptive effects of methadone combined with detomidine or acepromazine in horses.

PubMed

Lopes, C; Luna, S P L; Rosa, A C; Quarterone, C; Crosignani, N; Taylor, P M; Pantoja, J C; Puoli, J N P

2016-09-01

To investigate two protocols to provide antinociception in horses. To evaluate the antinociceptive effects of intravenous methadone combined with detomidine or acepromazine in adult horses. Randomised, blinded, crossover study. Mechanical, thermal and electrical stimuli were applied to the dorsal left and right metacarpus and coronary band of the left thoracic limb, respectively. A thermal stimulus was applied caudal to the withers. The horses were treated with saline (C), a combination of methadone (0.2 mg/kg bwt) and detomidine (10 μg/kg bwt) (MD) or methadone (0.2 mg/kg bwt) and acepromazine (0.05 mg/kg bwt) (MA) at 1 week intervals. Nociceptive thresholds were measured before and at 15 min intervals until 150 min after treatment. Wilcoxon rank-sum and Wilcoxon signed rank tests were used to compare data between groups at each time point and over time within each group, followed by the Bonferroni method to adjust the P value. The mechanical stimulus was the most sensitive test to differentiate the antinociceptive effects of the treatments. Mechanical thresholds were greater after MD than MA between 15 and 30 min and with both MD and MA these thresholds were greater than C from 15 to 60 min. Electrical and thermal limb thresholds were greater after MD than C at 15 and 45 min and at 15, 30, 45, 75 and 105 min, respectively. Thermal limb thresholds were greater with MA than C at 30 min. Thoracic thermal threshold in MD and MA were higher than C at 45, 75, 90 and 120 min and from 30 to 75 min, respectively. Methadone and acepromazine produced less pronounced mechanical antinociception than MD. © 2015 EVJ Ltd.

Psychedelics Promote Structural and Functional Neural Plasticity.

PubMed

Ly, Calvin; Greb, Alexandra C; Cameron, Lindsay P; Wong, Jonathan M; Barragan, Eden V; Wilson, Paige C; Burbach, Kyle F; Soltanzadeh Zarandi, Sina; Sood, Alexander; Paddy, Michael R; Duim, Whitney C; Dennis, Megan Y; McAllister, A Kimberley; Ori-McKenney, Kassandra M; Gray, John A; Olson, David E

2018-06-12

Atrophy of neurons in the prefrontal cortex (PFC) plays a key role in the pathophysiology of depression and related disorders. The ability to promote both structural and functional plasticity in the PFC has been hypothesized to underlie the fast-acting antidepressant properties of the dissociative anesthetic ketamine. Here, we report that, like ketamine, serotonergic psychedelics are capable of robustly increasing neuritogenesis and/or spinogenesis both in vitro and in vivo. These changes in neuronal structure are accompanied by increased synapse number and function, as measured by fluorescence microscopy and electrophysiology. The structural changes induced by psychedelics appear to result from stimulation of the TrkB, mTOR, and 5-HT2A signaling pathways and could possibly explain the clinical effectiveness of these compounds. Our results underscore the therapeutic potential of psychedelics and, importantly, identify several lead scaffolds for medicinal chemistry efforts focused on developing plasticity-promoting compounds as safe, effective, and fast-acting treatments for depression and related disorders. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Ketamine Protects Gamma Oscillations by Inhibiting Hippocampal LTD

PubMed Central

Huang, Lanting; Yang, Xiu-Juan; Huang, Ying; Sun, Eve Y.

2016-01-01

NMDA receptors have been widely reported to be involved in the regulation of synaptic plasticity through effects on long-term potentiation (LTP) and long-term depression (LTD). LTP and LTD have been implicated in learning and memory processes. Besides synaptic plasticity, it is known that the phenomenon of gamma oscillations is critical in cognitive functions. Synaptic plasticity has been widely studied, however it is still not clear, to what degree synaptic plasticity regulates the oscillations of neuronal networks. Two NMDA receptor antagonists, ketamine and memantine, have been shown to regulate LTP and LTD, to promote cognitive functions, and have even been reported to bring therapeutic effects in major depression and Alzheimer’s disease respectively. These compounds allow us to investigate the putative interrelationship between network oscillations and synaptic plasticity and to learn more about the mechanisms of their therapeutic effects. In the present study, we have identified that ketamine and memantine could inhibit LTD, without impairing LTP in the CA1 region of mouse hippocampus, which may underlie the mechanism of these drugs’ therapeutic effects. Our results suggest that NMDA-induced LTD caused a marked loss in the gamma power, and pretreatment with 10 μM ketamine prevented the oscillatory loss via its inhibitory effect on LTD. Our study provides a new understanding of the role of NMDA receptors on hippocampal plasticity and oscillations. PMID:27467732

Physiological evaluation of free-ranging moose (Alces alces) immobilized with etorphine-xylazine-acepromazine in Northern Sweden.

PubMed

Evans, Alina L; Fahlman, Åsa; Ericsson, Göran; Haga, Henning Andreas; Arnemo, Jon M

2012-12-31

Evaluation of physiology during capture and anesthesia of free-ranging wildlife is useful for determining the effect that capture methods have on both ecological research results and animal welfare. This study evaluates capture and anesthesia of moose (Alces alces) with etorphine-xylazine-acepromazine in Northern Sweden. Fifteen adult moose aged 3-15 years were darted from a helicopter with a combination of 3.37 mg etorphine, 75 mg xylazine, and 15 mg acepromazine. Paired arterial blood samples were collected 15 minutes apart with the first sample at 15-23 minutes after darting and were analyzed immediately with an i-STAT®1 Portable Clinical Analyzer. All animals developed hypoxemia (PaO2 <10 kPa) with nine animals having marked hypoxemia (PaO2 5.5-8 kPa). All moose were acidemic (ph<7.35) with nine moose having marked acidemia (pH<7.20). For PaCO2, 14 moose had mild hypercapnia (PaCO2 6-8 kPa) and two had marked hypercapnia (PaCO2>8 kPa). Pulse, respiratory rate, pH and HCO3 increased significantly over time from darting whereas lactate decreased. The hypoxemia found in this study is a strong indication for investigating alternative drug doses or combinations or treatment with supplemental oxygen.

Methadone in combination with acepromazine as premedication prior to neutering in the cat.

PubMed

Bortolami, Elisa; Murrell, Joanna C; Slingsby, Louisa S

2013-03-01

To investigate the safety, sedative and analgesic properties of methadone in combination with acepromazine prior to neutering in cats. Controlled clinical, block randomized, prospective, blinded study designed for regulatory purposes. 24 female and 21 male healthy cats. Cats received one of three opioids combined with acepromazine (0.05 mg kg(-1) ) intramuscularly (IM) for premedication: Group 1: buprenorphine (0.02 mg kg(-1) ), group 2: methadone (0.5 mg kg(-1) ), group 3 butorphanol (0.4 mg kg(-1) ). Sedation was assessed 30 minutes after premedication using a visual analogue scale (VAS) and simple descriptive scale. Anaesthesia was induced with alfaxalone and maintained with isoflurane in oxygen. Surgical ovariohysterectomy or castration was performed. Pain was assessed using an interactive VAS (IVAS) and mechanical nociceptive threshold (MNT) with a pressure rate onset device. Methadone (0.5 mg kg(-1) IM) and meloxicam (0.2 mg kg(-1) subcutaneously) were provided 6 and 8 hours after premedication respectively, or together as rescue analgesia (IVAS above 50). Sedation scores, induction agent dose, pain scores at all time points and rescue analgesia were not statistically different between groups. In methadone treated cats there was no significant variation in MNT over time, suggesting a possible anti-hyperalgesic action, whereas in the other two groups lower thresholds were recorded at various time points after surgery compared to baseline. No cats required rescue analgesia after the second dose of methadone. No perioperative adverse effects occurred. Methadone provided comparable sedation and analgesia to both buprenorphine and butorphanol when combined with acepromazine. Differences in analgesic efficacy between opioids might have been undetectable because of the surgical model and surgeon competency. Nevertheless, methadone is an effective analgesic in cats and its administration prior to feline neutering may be advantageous. © 2012 The Authors. Veterinary Anaesthesia and Analgesia. © 2012 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesiologists.

Maropitant prevented vomiting but not gastroesophageal reflux in anesthetized dogs premedicated with acepromazine-hydromorphone

PubMed Central

Johnson, Rebecca A

2015-01-01

Objective To evaluate the efficacy of maropitant for prevention of vomiting and gastroesophageal reflux (GER) in dogs following acepromazine-hydromorphone premedication and inhalation anesthesia. Study design Randomized, blinded, prospective clinical study. Animals Twenty-six dogs admitted for elective soft tissue or orthopedic procedures that were 3.1 ± 3.1 years of age and weighed 20.5 ± 11.4 kg. Methods Dogs were randomly assigned to one of two groups: Group M received maropitant (1.0 mg kg−1) and Group S received 0.9% saline (0.1 ml kg−1) intravenously 45–60 minutes before premedication with hydromorphone (0.1 mg kg−1) and acepromazine (0.03 mg kg−1) intramuscularly. An observer blinded to treatment documented any retching or vomiting for 20 minutes before induction with propofol (2–6 mg kg−1) and inhalation anesthesia. A pH probe inserted into the distal esophagus was used to detect GER. Results None of the dogs in Group M retched or vomited (0/13), 6/13 (46%) in Group S were observed to retch or vomit, and the difference between groups was significant (p = 0.015). There were no differences between groups in the number of dogs with GER (Group M: 4/13, Group S: 6/13 dogs) or the number of reflux events. Esophageal pH at the end of anesthesia was significantly lower in both M and S groups in dogs with GER versus dogs without GER (p = 0.004 and 0.011, respectively). Only dogs with GER in Group S had significantly lower pH at the end compared to the beginning of anesthesia (p = 0.004). Conclusions and clinical relevance Intravenous maropitant prevented retching and vomiting associated with acepromazine-hydromorphone premedication. Maropitant did not prevent the occurrence of GER. Fewer dogs in Group M developed GER but further study with a larger number of dogs is necessary to determine if there is a significant difference. PMID:24330310

Maropitant prevented vomiting but not gastroesophageal reflux in anesthetized dogs premedicated with acepromazine-hydromorphone.

PubMed

Johnson, Rebecca A

2014-07-01

To evaluate the efficacy of maropitant for prevention of vomiting and gastroesophageal reflux (GER) in dogs following acepromazine-hydromorphone premedication and inhalation anesthesia. Randomized, blinded, prospective clinical study. Twenty-six dogs admitted for elective soft tissue or orthopedic procedures that were 3.1 ±3.1 years of age and weighed 20.5 ± 11.4 kg. Dogs were randomly assigned to one of two groups: Group M received maropitant (1.0 mg kg(-1) ) and Group S received 0.9% saline (0.1 mL kg(-1) ) intravenously 45-60 minutes before premedication with hydromorphone (0.1 mg kg(-1) ) and acepromazine (0.03 mg kg(-1) ) intramuscularly. An observer blinded to treatment documented any retching or vomiting for 20 minutes before induction with propofol (2-6 mg kg(-1) ) and inhalation anesthesia. A pH probe inserted into the distal esophagus was used to detect GER. None of the dogs in Group M retched or vomited (0/13), 6/13 (46%) in Group S were observed to retch or vomit, and the difference between groups was significant (p = 0.015). There were no differences between groups in the number of dogs with GER (Group M: 4/13, Group S: 6/13 dogs) or the number of reflux events. Esophageal pH at the end of anesthesia was significantly lower in both M and S groups in dogs with GER versus dogs without GER (p = 0.004 and 0.011, respectively). Only dogs with GER in Group S had significantly lower pH at the end compared to the beginning of anesthesia (p = 0.004). Intravenous maropitant prevented retching and vomiting associated with acepromazine-hydromorphone premedication. Maropitant did not prevent the occurrence of GER. Fewer dogs in Group M developed GER but further study with a larger number of dogs is necessary to determine if there is a significant difference. © 2013 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

Immobilization of free-ranging male pacific walruses (Odobenus rosmarus divergens) with carfentanil citrate and naltrexone hydrochloride

USGS Publications Warehouse

Mulcahy, Daniel M.; Tuomi, P.A.; Garner, Gerald W.; Jay, Chadwick V.

2003-01-01

The major challenges in immobilization of free-ranging walruses (Odobenus rosmarus divergens) are to produce a deep level of anesthesia very quickly (to avoid darted animals from entering the water and drowning), and to find a drug or drug combination that requires only a small volume to be delivered by dart, is safe, reversible, and that provides an adequate period of immobilization to permit attachment of instruments, phlebotomy, and measuring. Tiletamine-zolazepam is recommended for immobilization of pinnipeds, with inhalant anesthesia recommended for more extensive procedures requiring better analgesia (Gales 1989). Drugs that have been used on free-ranging walruses include ketamine (Hagenbeck et al. 1975), phencyclidine combined with acepromazine (DeMaster et al. 1981), etorphine (Born and Knutsen 1990, Hills 1992, Griffiths et al. 1993), tiletamine-zolazepam (Stirling and Sjare 1988, Griffiths et al. 1993), medetomidine and ketamine (Lydersen et al. 1992), and carfentanil (Hills 1992, Lanthier et al. 1999). Carfentanil but not etorphine is presently licensed and available in the United States.Forty-eight adult male walruses were immobilized with carfentanil citrate in the summers of 1995-1997 at Maggy Beach (58°57’N, 161°76’W), a land haul-out located at Cape Peirce within the Togiak National Wildlife Refuge in southwest Alaska. The number of animals present during immobilizations ranged from three to several thousand. Criteria for choosing individual walruses included good body condition, the presence of two tusks of sufficient diameter for the attachment of radio transmitters, and presence of the animal at the edge of the herd. In addition, we chose animals that were resting quietly and which had not recently hauled out (as judged by skin color). Walruses were darted from ranges of approximately 10-15 m using a Cap-Chur rifle (Palmer Chemical and Equipment Co., Douglasville, Georgia, GA 30133). Carfentanil citrate (Wildlife Pharmaceuticals, Fort Collins, CO 80524) was administered by dart with a 10-cm needle to the lumbar region. Most animals received a dose of 2.7 or 3.0 mg of carfentanil. One animal received a second dose after the first syringe apparently burst on impact. Induction times were measured as being the time at which the animal collapsed, failed to respond to external stimuli, or as the time when the darter stood up and moved towards the animal.

Respiratory effects of cigarette smoke, dust, and histamine in newborn rabbits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trippenbach, T.; Kelly, G.

1988-02-01

We studied the respiratory effects of cigarette smoke, 5% histamine aerosol, and dust in unanesthetized 1- to 7-day-old rabbits in a body plethysmograph. Cigarette smoke immediately provoked the animal's arousal and irregular breathing. Histamine and dust had no effect in some of the youngest animals. In others, 5-15 s from the onset of the exposure to either of the two stimuli, respiratory rate increased and the depth of breathing decreased. These changes were more pronounced with age. The fact that effects of dust and aerosol lessened with time of exposure showed adaptation to the stimuli. The age dependence of themore » reflex response was also observed after injection of 50 micrograms of histamine per kilogram into the external jugular vein in anesthetized (50 mg ketamine + 3 mg acepromazine per kg) and tracheostomized rabbits during the 1st wk of life. In 1-day-old animals, a short-lasting excitation was followed by apnea or a prolongation of expiratory phase. Peak amplitude of the diaphragmatic EMG (EMGdi) increased in all animals, but only in the youngest was the EMGdi increase paralleled by an increase in tidal volume. In vagotomized animals or animals pretreated with H1-blocker, histamine never affected timing parameters in animals greater than 1 day old. In the youngest animals, respiratory depression due to histamine was not abolished after vagotomy or promethazine. The results imply that inputs from the upper airways and the rapidly adapting pulmonary mechanoreceptors exert their effects on the pattern of breathing immediately after birth in rabbits. The importance of those inputs increases with maturation.« less

Effect of meloxicam and carprofen on renal function when administered to healthy dogs prior to anesthesia and painful stimulation.

PubMed

Crandell, Dawn E; Mathews, Karol A; Dyson, Doris H

2004-10-01

To determine whether administration of the nonsteroidal anti-inflammatory drugs meloxicam or carprofen to healthy dogs that were subsequently anesthetized and subjected to painful electrical stimulation has adverse effects on renal function as measured by glomerular filtration rate (GFR) and evaluation of serum concentrations of urea and creatinine. 6 male and 6 female healthy young-adult Beagles. A study was conducted in accordance with a randomized crossover Latin-square design. One of 3 treatments (saline [0.9% NaCl] solution, 0.2 mg of meloxicam/kg, or 4.0 mg of carprofen/kg) was administered i.v. 1 hour before anesthesia was induced by use of drugs in accordance with a standard anesthetic protocol (butorphanol tartrate and acepromazine maleate as preanesthetic medications, ketamine hydrochloride and diazepam for induction, and maintenance with isoflurane). Anesthetized dogs were subjected to intermittent electrical stimulation for 30 minutes. Direct, mean arterial blood pressure; heart rate; and respiratory rate were monitored. End-tidal isoflurane concentration was maintained at 1.5 times the minimum alveolar concentration. The GFR, as measured by plasma clearance of 99mTc-diethylenetriaminepentaacetic acid, and serum concentrations of serum and creatinine were determined 24 hours after induction of anesthesia. Neither meloxicam nor carprofen significantly affected GFR or serum concentrations of urea and creatinine, compared with values for the saline treatment. When administered 1 hour before onset of anesthesia and painful electrical stimulation, meloxicam or carprofen did not cause clinically important alterations of renal function in young healthy dogs.

Recent advances in intravenous anaesthesia.

PubMed

Sneyd, J R

2004-11-01

Efforts to develop new hypnotic compounds continue, although several have recently failed in development. Propofol has been reformulated in various presentations with and without preservatives. Pharmacokinetic and pharmacodynamic differences exist between some of these preparations, and it is currently unclear whether any have substantial advantages over the original presentation. The use of target-controlled infusion (TCI) has been extended to include paediatric anaesthesia and sedation. Application of TCI to remifentanil is now licensed. Linking of electroencephalogram (EEG) monitoring to TCI for closed-loop anaesthesia remains a research tool, although commercial development may follow. The availability of stereoisomer ketamine and improved understanding of its pharmacology have increased non-anaesthetic use of ketamine as an adjunct analgesic. It may be useful in subhypnotic doses for postsurgical patients with pain refractory to morphine administration.

Agmatine potentiates neuroprotective effects of subthreshold concentrations of ketamine via mTOR/S6 kinase signaling pathway.

PubMed

Tavares, Mauren K; Dos Reis, Suellen; Platt, Nicolle; Heinrich, Isabella A; Wolin, Ingrid A V; Leal, Rodrigo B; Kaster, Manuella P; Rodrigues, Ana Lúcia S; Freitas, Andiara E

2018-05-12

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is one of the most robust neurobiological findings in the pathophysiology of major depressive disorder (MDD) over the last 40 years. The persistent increase in glucocorticoids levels induces morphological and anatomical changes in the brain, especially in the hippocampus. Ketamine represents a major advance for the treatment of MDD, however the psychotomimetic effects of this compound limit its widespread use. Agmatine is a neuromodulator that has been shown to be a putative novel and well-tolerated antidepressant/augmenter drug. In this study, the exposure of HT22 hippocampal neuronal cell line to corticosterone (50 μM) induced a significant neuronal cell death. Interestingly, the incubation of HT22 cells with the fast-acting antidepressant drug ketamine (1 μM) prevented the corticosterone-induced toxicity. Similarly, agmatine caused a significant cytoprotection at the concentration of 0.1 μM against corticosterone (50 μM) cell damage. Notably, the incubation with a subthreshold concentration of ketamine (0.01 μM) in combination with a subthreshold concentration of agmatine (0.001 μM) prevented the neuronal damage elicited by corticosterone (50 μM). A 24 h co-incubation with subthreshold concentrations of ketamine (0.01 μM) and agmatine (0.001 μM) was able to cause a significant increase in the phosphorylation levels of Akt (Ser 473 ) and p70S6 kinase (Thr 389 ) as well as PSD95 immunocontent. Neither glycogen synthase kinase-3β (Ser 9 ) phosphorylation nor β catenin immunocontent were altered by a 24 h co-incubation period. Finally, the co-incubation of cells for 30 min did not produce any effect in the phosphorylation or immunocontent of any protein investigated. Taken together, our results support the notion that the combination of subthreshold concentrations of ketamine and agmatine has cytoprotective effects against corticosterone-induced cell death. This effect is accompanied by its ability to activate Akt and mTOR/S6 kinase signaling pathway, and increase the expression of synaptic proteins. Copyright © 2018. Published by Elsevier Ltd.

Cost-Effectiveness of Postoperative Ketamine in Chiari Decompression.

PubMed

McDowell, Michael M; Alhourani, Ahmad; Pearce-Smith, Beverly A; Mazurkiewicz, Anna; Friedlander, Robert M

2018-02-01

In Chiari I patients, postoperative pain and discomfort frequently slow the transition back to the home setting. We sought to determine the effect of standardized ketamine infusion protocols on hospital length of stay (LOS). This retrospective cohort study reviewed 100 consecutive adult patients undergoing Chiari I decompression. Fifty-nine patients were placed on a 2-3 mg/hr ketamine drip until postoperative day 1. This group was compared with a group who received 2-3 mg/hr of ketamine until postoperative day 2 (19 patients) and patients who did not receive ketamine at all (22 patients). Clinical characteristics, opioid use, LOS, and relative hospitalization costs were assessed. All narcotic amounts were converted into milligram equivalents of morphine. LOS of the short-ketamine group was 46.5 hours when compared with the long-ketamine group (66.8 hours) and no-ketamine group (56.9 hours). There was a statistically significant difference when comparing the short-ketamine group with the long-ketamine group and no-ketamine group together (P < 0.001), as well as when compared individually (P = 0.001 and 0.004). The mean cost of hospitalization was 20% less when a short-ketamine protocol was used (P < 0.001). Mean morphine milligram equivalents used postoperatively were 148 mg in the short-ketamine group, 196 mg in the long-ketamine group, and 187 mg in the no-ketamine group (P = 0.65). No adverse events from ketamine were noted. Ketamine at subanesthetic levels may be an effective tool to facilitate early return home postoperatively and may significantly reduce medical costs. Copyright © 2017 Elsevier Inc. All rights reserved.

Development of a rapid screening test for veterinary sedatives and the beta-blocker carazolol in porcine kidney by ELISA.

PubMed

Cooper, John; Delahaut, Phillippe; Fodey, Terence L; Elliott, Christopher T

2004-02-01

Sedatives and tranquillisers are frequently used to reduce stress during the transportation of food producing animals. The most widely used classes of sedatives include the butyrophenone azaperone, the phenothiazines acepromazine, propionylpromazine, chlorpromazine and the [small beta]-blocker, carazolol. For regulatory control purposes, tolerances for azaperone and carazolol have been set by the European Union as 100 and 25 [micro sign]g kg(-1), respectively. Furthermore, the use of the phenothiazines is prohibited and therefore has a zero tolerance. A method for the detection of residues of five tranquillisers and one [small beta]-blocker using a single ELISA plate has been developed. Kidney samples (2.5 g) were extracted with dichloromethane and applied to a competitive enzyme immunoassay using three polyclonal antibodies raised in rabbits against azaperol, propionylpromazine and carazolol conjugates. In sample matrix, the azaperol antibody cross-reacted 28.0% with azaperone and the propionylpromazine antibody cross-reacted 24.9% with acepromazine and 11.7% with chlorpromazine. In the ELISA, the detection capabilities of the six sedatives, azaperol, azaperone, carazolol, acepromazine, chlorpromazine, and propionylpromazine are 5, 15, 5, 5, 20 and 5 [micro sign]g kg(-1), respectively. The proposed method is a sensitive and rapid multi-residue technique that offers a cost effective alternative to current published procedures, without any concession on the ability to detect sedative misuse.

Physiological evaluation of free-ranging moose (Alces alces) immobilized with etorphine-xylazine-acepromazine in Northern Sweden

PubMed Central

2012-01-01

Background Evaluation of physiology during capture and anesthesia of free-ranging wildlife is useful for determining the effect that capture methods have on both ecological research results and animal welfare. This study evaluates capture and anesthesia of moose (Alces alces) with etorphine-xylazine-acepromazine in Northern Sweden. Methods Fifteen adult moose aged 3–15 years were darted from a helicopter with a combination of 3.37 mg etorphine, 75 mg xylazine, and 15 mg acepromazine. Paired arterial blood samples were collected 15 minutes apart with the first sample at 15–23 minutes after darting and were analyzed immediately with an i-STAT®1 Portable Clinical Analyzer. Results All animals developed hypoxemia (PaO2 <10 kPa) with nine animals having marked hypoxemia (PaO2 5.5-8 kPa). All moose were acidemic (ph<7.35) with nine moose having marked acidemia (pH<7.20). For PaCO2, 14 moose had mild hypercapnia (PaCO2 6-8 kPa) and two had marked hypercapnia (PaCO2>8 kPa). Pulse, respiratory rate, pH and HCO3 increased significantly over time from darting whereas lactate decreased. Conclusions The hypoxemia found in this study is a strong indication for investigating alternative drug doses or combinations or treatment with supplemental oxygen. PMID:23276208

Towards an Explanation of Subjective Ketamine Experiences among Young Injection Drug Users

PubMed Central

LANKENAU, STEPHEN E.; SANDERS, BILL; BLOOM, JENNIFER JACKSON; HATHAZI, DODI

2008-01-01

Ketamine is a dissociative anesthetic with powerful sedative and hallucinogenic properties. Despite the wide variability in reported subjective experiences, no study has attempted to describe the particular factors that shape these experiences. This manuscript is based upon a sample of 213 young injection drug users recruited in New York, New Orleans, and Los Angeles with histories of ketamine use. Qualitative interviews focused on specific ketamine events, such as first injection of ketamine, most recent injection of ketamine, and most recent experience sniffing ketamine. Findings indicate that six factors impacted both positive and negative ketamine experiences: polydrug use, drug using history, mode of administration, quantity and quality of ketamine, user group, and setting. Most subjective experiences during any given ketamine event were shaped by a combination of these factors. Additionally, subjective ketamine experiences were particularly influenced by a lifestyle characterized by homelessness and traveling. PMID:18941540

R-ketamine: a rapid-onset and sustained antidepressant without psychotomimetic side effects

PubMed Central

Yang, C; Shirayama, Y; Zhang, J-c; Ren, Q; Yao, W; Ma, M; Dong, C; Hashimoto, K

2015-01-01

Although the efficacy of racemate ketamine, a rapid onset and sustained antidepressant, for patients with treatment-resistant depression was a serendipitous finding, clinical use of ketamine is limited, due to psychotomimetic side effects and abuse liability. Behavioral and side-effect evaluation tests were applied to compare the two stereoisomers of ketamine. To elucidate their potential therapeutic mechanisms, we examined the effects of these stereoisomers on brain-derived neurotrophic factor (BDNF)–TrkB signaling, and synaptogenesis in selected brain regions. In the social defeat stress and learned helplessness models of depression, R-ketamine showed a greater potency and longer-lasting antidepressant effect than S-ketamine (esketamine). Furthermore, R-ketamine induced a more potent beneficial effect on decreased dendritic spine density, BDNF–TrkB signaling and synaptogenesis in the prefrontal cortex (PFC), CA3 and dentate gyrus (DG) of the hippocampus from depressed mice compared with S-ketamine. However, neither stereoisomer affected these alterations in the nucleus accumbens of depressed mice. In behavioral tests for side effects, S-ketamine, but not R-ketamine, precipitated behavioral abnormalities, such as hyperlocomotion, prepulse inhibition deficits and rewarding effects. In addition, a single dose of S-ketamine, but not R-ketamine, caused a loss of parvalbumin (PV)-positive cells in the prelimbic region of the medial PFC and DG. These findings suggest that, unlike S-ketamine, R-ketamine can elicit a sustained antidepressant effect, mediated by increased BDNF–TrkB signaling and synaptogenesis in the PFC, DG and CA3. R-ketamine appears to be a potent, long-lasting and safe antidepressant, relative to S-ketamine, as R-ketamine appears to be free of psychotomimetic side effects and abuse liability. PMID:26327690

Repeated ketamine administration alters N-methyl-d-aspartic acid receptor subunit gene expression: Implication of genetic vulnerability for ketamine abuse and ketamine psychosis in humans

PubMed Central

Lipsky, Robert H

2015-01-01

For more than 40 years following its approval by the Food and Drug Administration (FDA) as an anesthetic, ketamine, a non-competitive N-methyl-d-aspartic acid (NMDA) receptor antagonist, has been used as a tool of psychiatric research. As a psychedelic drug, ketamine induces psychotic symptoms, cognitive impairment, and mood elevation, which resemble some symptoms of schizophrenia. Recreational use of ketamine has been increasing in recent years. However, little is known of the underlying molecular mechanisms responsible for ketamine-associated psychosis. Recent animal studies have shown that repeated ketamine administration significantly increases NMDA receptor subunit gene expression, in particular subunit 1 (NR1 or GluN1) levels. This results in neurodegeneration, supporting a potential mechanism where up-regulation of NMDA receptors could produce cognitive deficits in chronic ketamine abuse patients. In other studies, NMDA receptor gene variants are associated with addictive behavior. Here, we focus on the roles of NMDA receptor gene subunits in ketamine abuse and ketamine psychosis and propose that full sequencing of NMDA receptor genes may help explain individual vulnerability to ketamine abuse and ketamine-associated psychosis. PMID:25245072

Cognitive behavior therapy may sustain antidepressant effects of intravenous ketamine in treatment-resistant depression

PubMed Central

Wilkinson, Samuel T.; Wright, DaShaun; Fasula, Madonna K.; Fenton, Lisa; Griepp, Matthew; Ostroff, Robert B.; Sanacora, Gerard

2017-01-01

Introduction Ketamine has shown rapid though short-lived antidepressant effects. The possibility of concerning neurobiological changes following repeated exposure to the drug motivate the development of strategies that obviate or minimize the need for longer-term treatment with ketamine. In this open-label trial, we investigated whether cognitive behavioral therapy (CBT) can sustain or extend ketamine's antidepressant effects. Methods Patients who were pursuing ketamine infusion therapy for treatment-resistant depression (TRD) were invited to participate in the study. If enrolled, the subjects initiated a 12-session, 10-week course of CBT concurrently with a short 4-treatment, 2-week course of intravenous ketamine (0.5mg/kg infused over 40 mins) provided under a standardized clinical protocol. Results Sixteen participants initiated the protocol, with 8 (50%) attaining a response to the ketamine and 7 (43.8%) achieving remission during the first two weeks of protocol. Among ketamine responders, the relapse rate at the end of the CBT course (8 weeks following the last ketamine exposure) was 25% (2/8). On longer-term follow up, 5 of 8 subjects eventually relapsed, the median time-to-relapse being 12 weeks following ketamine exposure. Among ketamine remitters, 3 of 7 retained remission until at least 4 weeks following the last ketamine exposure, with 2 retaining remission through 8 weeks following ketamine exposure. Ketamine non-responders did not appear to benefit from CBT. Conclusions CBT may sustain the antidepressant effects of ketamine in TRD. Well-powered randomized controlled trials are warranted to further investigate this treatment combination as a way to sustain ketamine's antidepressant effects. PMID:28490030

Mechanistic Target of Rapamycin-Independent Antidepressant Effects of (R)-Ketamine in a Social Defeat Stress Model.

PubMed

Yang, Chun; Ren, Qian; Qu, Youge; Zhang, Ji-Chun; Ma, Min; Dong, Chao; Hashimoto, Kenji

2018-01-01

The role of the mechanistic target of rapamycin (mTOR) signaling in the antidepressant effects of ketamine is controversial. In addition to mTOR, extracellular signal-regulated kinase (ERK) is a key signaling molecule in prominent pathways that regulate protein synthesis. (R)-Ketamine has a greater potency and longer-lasting antidepressant effects than (S)-ketamine. Here we investigated whether mTOR signaling and ERK signaling play a role in the antidepressant effects of two enantiomers. The effects of mTOR inhibitors (rapamycin and AZD8055) and an ERK inhibitor (SL327) on the antidepressant effects of ketamine enantiomers in the chronic social defeat stress (CSDS) model (n = 7 or 8) and on those of ketamine enantiomers in these signaling pathways in mouse brain regions were examined. The intracerebroventricular infusion of rapamycin or AZD8055 blocked the antidepressant effects of (S)-ketamine, but not (R)-ketamine, in the CSDS model. Furthermore, (S)-ketamine, but not (R)-ketamine, significantly attenuated the decreased phosphorylation of mTOR and its downstream effector, ribosomal protein S6 kinase, in the prefrontal cortex of susceptible mice after CSDS. Pretreatment with SL327 blocked the antidepressant effects of (R)-ketamine but not (S)-ketamine. Moreover, (R)-ketamine, but not (S)-ketamine, significantly attenuated the decreased phosphorylation of ERK and its upstream effector, mitogen-activated protein kinase/ERK kinase, in the prefrontal cortex and hippocampal dentate gyrus of susceptible mice after CSDS. This study suggests that mTOR plays a role in the antidepressant effects of (S)-ketamine, but not (R)-ketamine, and that ERK plays a role in (R)-ketamine's antidepressant effects. Thus, it is unlikely that the activation of mTOR signaling is necessary for antidepressant actions of (R)-ketamine. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Longitudinal Trajectories of Ketamine Use among Young Injection Drug Users

PubMed Central

Lankenau, Stephen E.; Bloom, Jennifer Jackson; Shin, Charles

2010-01-01

Background Ketamine is a dissociative anesthetic that became increasing popular in the club and rave scene in the 1980s and 1990s. Reports surfaced in the late 1990s indicating that ketamine was being injected in several U.S. cities by young injection drug users (IDUs). Since all studies on ketamine injection were cross-sectional, a longitudinal study was undertaken in 2005 to determine: characteristics of young IDUs who continue to inject ketamine; frequency of ketamine injection over an extended time period; risks associated with ongoing ketamine injection; and environmental factors that impact patterns of ketamine use. Methods Young IDUs aged 16 to 29 with a history of injecting ketamine (n=101) were recruited from public locations in Los Angeles and followed during a two-year longitudinal study. A semi-structured instrument captured quantitative and qualitative data on patterns of ketamine injection and other drug use. A statistical model sorted IDUs who completed three or more interviews (n=66) into three groups based upon patterns of ketamine injection at baseline and follow-up. Qualitative analysis focused on detailed case studies within each group. Results IDUs recruited at baseline were typically in their early 20s, male, heterosexual, white, and homeless. Longitudinal injection trajectories included: “Moderates,” who injected ketamine several times per year (n=5); “Occasionals,” who injected ketamine approximately once per year (n=21); and “Abstainers,” who did not inject any ketamine during follow-up (n=40). Findings suggest that ketamine is infrequently injected compared to other drugs such as heroin, cocaine, and methamphetamine. Most IDUs who begin injecting ketamine will stop or curb use due to: negative or ambivalent experiences associated with ketamine; an inability to find the drug due to declining supply; or maturing out of injecting drugs more generally. Conclusion Reducing ketamine injection among young IDUs may best be accomplished by targeting particular groups of IDUs identified in this study, such as homeless youth and homeless travelers. PMID:20138747

Estimation of the contribution of norketamine to ketamine-induced acute pain relief and neurocognitive impairment in healthy volunteers.

PubMed

Olofsen, Erik; Noppers, Ingeborg; Niesters, Marieke; Kharasch, Evan; Aarts, Leon; Sarton, Elise; Dahan, Albert

2012-08-01

The N-methyl-D-aspartate receptor antagonist ketamine is metabolized in the liver into its active metabolite norketamine. No human data are available on the relative contribution of norketamine to ketamine-induced analgesia and side effects. One approach to assess the ketamine and norketamine contributions is by measuring the ketamine effect at varying ketamine and norketamine plasma concentrations using the CYP450 inducer rifampicin. In 12 healthy male volunteers the effect of rifampicin versus placebo pretreatment on S-ketamine-induced analgesia and cognition was quantified; the S-ketamine dosage was 20 mg/h for 2 h. The relative ketamine and norketamine contribution to effect was estimated using a linear additive population pharmacokinetic-pharmacodynamic model. S-ketamine produced significant analgesia, psychotropic effects (drug high), and cognitive impairment (including memory impairment and reduced psychomotor speed, reaction time, and cognitive flexibility). Modeling revealed a negative contribution of S-norketamine to S-ketamine- induced analgesia and absence of contribution to cognitive impairment. At ketamine and norketamine effect concentrations of 100 ng/ml and 50 ng/ml, respectively, the ketamine contribution to analgesia is -3.8 cm (visual analog pain score) versus a contribution of norketamine of +1.5 cm, causing an overall effect of -2.3 cm. The blood-effect site equilibration half-life ranged from 0 (cognitive flexibility) to 11.8 (pain intensity) min and was 6.1 min averaged across all endpoints. This first observation that norketamine produces effects in the opposite direction of ketamine requires additional proof. It can explain the observation of ketamine-related excitatory phenomena (such as hyperalgesia and allodynia) upon the termination of ketamine infusions.

Beyond Ketamine: New Approaches to the Development of Safer Antidepressants.

PubMed

Chaki, Shigeyuki

2017-01-01

Ketamine has been reported to exert rapid and sustained antidepressant effects in patients with depression, including patients with treatment-resistant depression. However, ketamine has several drawbacks such as psychotomimetic/dissociative symptoms, abuse potential and neurotoxicity, all of which prevent its routine use in daily clinical practice. Therefore, development of novel agents with fewer safety and usage concerns for the treatment of depression has been actively investigated. From this standpoint, searching for active substances (stereoisomers and metabolites) and agents acting on the N-methyl-D-aspartate (NMDA) receptor have recently gained much attention. The first approach includes stereoisomers of ketamine, (R)-ketamine and (S)-ketamine. Although (S)-ketamine has been considered as the active stereoisomer of racemic ketamine, recently, (R)-ketamine has been demonstrated to exert even more prolonged antidepressant effects in animal models than (S)-ketamine. Moreover, ketamine is rapidly metabolized into several metabolites, and some metabolites are speculated as being active substances exerting antidepressant effects. Of such metabolites, one in particular, namely, (2R,6R)-hydroxynorketamine, has been reported to be responsible for the antidepressant effects of ketamine. The second approach includes agents acting on the NMDA receptor, such as glycine site modulators and GluN2B subunit-selective antagonists. These agents have been tested in patients with treatment-resistant depression, and have been found to exhibit rapid antidepressant effects like ketamine. The above approaches may be useful to overcome the drawbacks of ketamine. Elucidation of the mechanisms of action of ketamine may pave the way for the development of antidepressant that are safer, but as potent and rapidly acting as ketamine. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Beyond Ketamine: New Approaches to the Development of Safer Antidepressants

PubMed Central

Chaki, Shigeyuki

2017-01-01

Background: Ketamine has been reported to exert rapid and sustained antidepressant effects in patients with depression, including patients with treatment-resistant depression. However, ketamine has several drawbacks such as psychotomimetic/dissociative symptoms, abuse potential and neurotoxicity, all of which prevent its routine use in daily clinical practice. Methods: Therefore, development of novel agents with fewer safety and usage concerns for the treatment of depression has been actively investigated. From this standpoint, searching for active substances (stereoisomers and metabolites) and agents acting on the N-methyl-D-aspartate (NMDA) receptor have recently gained much attention. Results: The first approach includes stereoisomers of ketamine, (R)-ketamine and (S)-ketamine. Although (S)-ketamine has been considered as the active stereoisomer of racemic ketamine, recently, (R)-ketamine has been demonstrated to exert even more prolonged antidepressant effects in animal models than (S)-ketamine. Moreover, ketamine is rapidly metabolized into several metabolites, and some metabolites are speculated as being active substances exerting antidepressant effects. Of such metabolites, one in particular, namely, (2R,6R)-hydroxynorketamine, has been reported to be responsible for the antidepressant effects of ketamine. The second approach includes agents acting on the NMDA receptor, such as glycine site modulators and GluN2B subunit-selective antagonists. These agents have been tested in patients with treatment-resistant depression, and have been found to exhibit rapid antidepressant effects like ketamine. Conclusion: The above approaches may be useful to overcome the drawbacks of ketamine. Elucidation of the mechanisms of action of ketamine may pave the way for the development of antidepressant that are safer, but as potent and rapidly acting as ketamine. PMID:28228087

Ketamine: A Review of Clinical Pharmacokinetics and Pharmacodynamics in Anesthesia and Pain Therapy.

PubMed

Peltoniemi, Marko A; Hagelberg, Nora M; Olkkola, Klaus T; Saari, Teijo I

2016-09-01

Ketamine is a phencyclidine derivative, which functions primarily as an antagonist of the N-methyl-D-aspartate receptor. It has no affinity for gamma-aminobutyric acid receptors in the central nervous system. Ketamine shows a chiral structure consisting of two optical isomers. It undergoes oxidative metabolism, mainly to norketamine by cytochrome P450 (CYP) 3A and CYP2B6 enzymes. The use of S-ketamine is increasing worldwide, since the S(+)-enantiomer has been postulated to be a four times more potent anesthetic and analgesic than the R(-)-enantiomer and approximately two times more effective than the racemic mixture of ketamine. Because of extensive first-pass metabolism, oral bioavailability is poor and ketamine is vulnerable to pharmacokinetic drug interactions. Sublingual and nasal formulations of ketamine are being developed, and especially nasal administration produces rapid maximum plasma ketamine concentrations with relatively high bioavailability. Ketamine produces hemodynamically stable anesthesia via central sympathetic stimulation without affecting respiratory function. Animal studies have shown that ketamine has neuroprotective properties, and there is no evidence of elevated intracranial pressure after ketamine dosing in humans. Low-dose perioperative ketamine may reduce opioid consumption and chronic postsurgical pain after specific surgical procedures. However, long-term analgesic effects of ketamine in chronic pain patients have not been demonstrated. Besides analgesic properties, ketamine has rapid-acting antidepressant effects, which may be useful in treating therapy-resistant depressive patients. Well-known psychotomimetic and cognitive adverse effects restrict the clinical usefulness of ketamine, even though fewer psychomimetic adverse effects have been reported with S-ketamine in comparison with the racemate. Safety issues in long-term use are yet to be resolved.

The use of a battery of pain models to detect analgesic properties of compounds: a two‐part four‐way crossover study

PubMed Central

Okkerse, Pieter; van Amerongen, Guido; de Kam, Marieke L.; Stevens, Jasper; Butt, Richard P.; Gurrell, Rachel; Dahan, Albert; van Gerven, Joop M.; Hay, Justin L.

2017-01-01

Aim The aim was to investigate the ability of a battery of pain models to detect analgesic properties of commonly used analgesics in healthy subjects. Methods The battery consisted of tests eliciting electrical, mechanical and thermal (contact heat and cold pressor)‐pain and included a UVB model, the thermal grill illusion and a paradigm of conditioned pain modulation. Subjects were administered fentanyl 3 μg kg–1, phenytoin 300 mg, (S)‐ketamine 10 mg and placebo (part I), or imipramine 100 mg, pregabalin 300 mg, ibuprofen 600 mg and placebo (part II). Pain measurements were performed at baseline and up to 10 h post‐dose. Endpoints were analysed using a mixed model analysis of variance. Results Sixteen subjects (8 female) completed each part. The pain tolerance threshold (PTT) for electrical stimulation was increased (all P < 0.05) compared to placebo for (S)‐ketamine (+10.1%), phenytoin (+8.5%) and pregabalin (+10.8%). The PTT for mechanical pain was increased by pregabalin (+14.1%). The cold pressor PTT was increased by fentanyl (+17.1%) and pregabalin (+46.4%). Normal skin heat pain detection threshold was increased by (S)‐ketamine (+3.3%), fentanyl (+2.8%) and pregabalin (+4.1%). UVB treated skin pain detection threshold was increased by fentanyl (+2.6%) and ibuprofen (+4.0%). No differences in conditioned pain modulation were observed. Conclusion This study shows that these pain models are able to detect changes in pain thresholds after administration of different classes of analgesics in healthy subjects. The analgesic compounds all showed a unique profile in their effects on the pain tasks administered. PMID:27862179

The use of a battery of pain models to detect analgesic properties of compounds: a two-part four-way crossover study.

PubMed

Okkerse, Pieter; van Amerongen, Guido; de Kam, Marieke L; Stevens, Jasper; Butt, Richard P; Gurrell, Rachel; Dahan, Albert; van Gerven, Joop M; Hay, Justin L; Groeneveld, Geert Jan

2017-05-01

The aim was to investigate the ability of a battery of pain models to detect analgesic properties of commonly used analgesics in healthy subjects. The battery consisted of tests eliciting electrical, mechanical and thermal (contact heat and cold pressor)-pain and included a UVB model, the thermal grill illusion and a paradigm of conditioned pain modulation. Subjects were administered fentanyl 3 μg kg -1 , phenytoin 300 mg, (S)-ketamine 10 mg and placebo (part I), or imipramine 100 mg, pregabalin 300 mg, ibuprofen 600 mg and placebo (part II). Pain measurements were performed at baseline and up to 10 h post-dose. Endpoints were analysed using a mixed model analysis of variance. Sixteen subjects (8 female) completed each part. The pain tolerance threshold (PTT) for electrical stimulation was increased (all P < 0.05) compared to placebo for (S)-ketamine (+10.1%), phenytoin (+8.5%) and pregabalin (+10.8%). The PTT for mechanical pain was increased by pregabalin (+14.1%). The cold pressor PTT was increased by fentanyl (+17.1%) and pregabalin (+46.4%). Normal skin heat pain detection threshold was increased by (S)-ketamine (+3.3%), fentanyl (+2.8%) and pregabalin (+4.1%). UVB treated skin pain detection threshold was increased by fentanyl (+2.6%) and ibuprofen (+4.0%). No differences in conditioned pain modulation were observed. This study shows that these pain models are able to detect changes in pain thresholds after administration of different classes of analgesics in healthy subjects. The analgesic compounds all showed a unique profile in their effects on the pain tasks administered. © 2016 The British Pharmacological Society.

Acute agmatine administration, similar to ketamine, reverses depressive-like behavior induced by chronic unpredictable stress in mice.

PubMed

Neis, Vivian B; Bettio, Luis E B; Moretti, Morgana; Rosa, Priscila B; Ribeiro, Camille M; Freitas, Andiara E; Gonçalves, Filipe M; Leal, Rodrigo B; Rodrigues, Ana Lúcia S

Agmatine is an endogenous neuromodulator that has been shown to have antidepressant-like properties. We have previously demonstrated that it can induce a rapid increase in BDNF levels after acute administration, suggesting that agmatine may be a fast-acting antidepressant. To investigate this hypothesis, the present study evaluated the effects of a single administration of agmatine in mice subjected to chronic unpredictable stress (CUS), a model of depression responsive only to chronic treatment with conventional antidepressants. The ability of agmatine to reverse CUS-induced behavioral and biochemical alterations was evaluated and compared with those elicited by the fast-acting antidepressant (ketamine) and the conventional antidepressant (fluoxetine). After exposed to CUS for 14days, mice received a single oral dose of agmatine (0.1mg/kg), ketamine (1mg/kg) or fluoxetine (10mg/kg), and were submitted to behavioral evaluation after 24h. The exposure to CUS caused an increased immobility time in the tail suspension test (TST) but did not change anhedonic-related parameters in the splash test. Our findings provided evidence that, similarly to ketamine, agmatine is able to reverse CUS-induced depressive-like behavior in the TST. Western blot analyses of prefrontal cortex (PFC) demonstrated that mice exposed to CUS and/or treated with agmatine, fluoxetine or ketamine did not present alterations in the immunocontent of synaptic proteins [i.e. GluA1, postsynaptic density protein 95 (PSD-95) and synapsin]. Altogether, our findings indicate that a single administration of agmatine is able to reverse behavioral alterations induced by CUS in the TST, suggesting that this compound may have fast-acting antidepressant-like properties. However, there was no alteration in the levels of synaptic proteins in the PFC, a result that need to be further investigated in other time points. Copyright © 2016 Elsevier Inc. All rights reserved.

Sub-anesthetic concentrations of (R,S)-ketamine metabolites inhibit acetylcholine-evoked currents in α7 nicotinic acetylcholine receptors

PubMed Central

Moaddel, Ruin; Abdrakhmanova, Galia; Kozak, Joanna; Jozwiak, Krzysztof; Toll, Lawrence; Jimenez, Lucita; Rosenberg, Avraham; Tran, Thao; Xiao, Yingxian; Zarate, Carlos A.; Wainer, Irving W.

2012-01-01

The effect of the (R,S)-ketamine metabolites (R,S)-norketamine, (R,S)-dehydronorketamine, (2S,6S)-hydroxynorketamine and (2R,6R)- hydroxynorketamine on the activity of α7 and α3β4 neuronal nicotinic acetylcholine receptors was investigated using patch-clamp techniques. The data indicated that (R,S)-dehydronorketamine inhibited acetylcholine-evoked currents in α7-nicotinic acetylcholine receptor, IC50 = 55 ± 6 nM, and that (2S,6S)-hydroxynorketamine, (2R,6R)-hydroxynorketamine and (R,S)-norketamine also inhibited α7-nicotinic acetylcholine receptor function at concentrations ≤1μM, while (R,S)-ketamine was inactive at these concentrations. The inhibitory effect of (R,S)-dehydronorketamine was voltage-independent and the compound did not competitively displace selective α7-nicotinic acetylcholine receptor ligands [125I]-α-bungarotoxin and [3H]-epibatidine indicating that (R,S)-dehydronorketamine is a negative allosteric modulator of the α7-nicotinic acetylcholine receptor. (R,S)-Ketamine and (R,S)-norketamine inhibited (S)-nicotine-induced whole-cell currents in cells expressing α3β4-nicotinic acetylcholine receptor, IC50 3.1 and 9.1μM, respectively, while (R,S)-dehydronorketamine, (2S,6S)-hydroxynorketamine and (2R,6R)-hydroxynorketamine were weak inhibitors, IC50 >100μM. The binding affinities of (R,S)-dehydronorketamine, (2S,6S)-hydroxynorketamine and (2R,6R)-hydroxynorketamine at the NMDA receptor were also determined using rat brain membranes and the selective NMDA receptor antagonist [3H]-MK-801. The calculated Ki values were 38.95 μM for (S)-dehydronorketamine, 21.19 μM for (2S,6S)-hydroxynorketamine and > 100 μM for (2R,6R)-hydroxynorketamine. The results suggest that the inhibitory activity of ketamine metabolites at the α7-nicotinic acetylcholine receptor may contribute to the clinical effect of the drug. PMID:23183107

Reinforcing properties of an intermittent, low dose of ketamine in rats: effects of sex and cycle.

PubMed

Wright, Katherine N; Strong, Caroline E; Addonizio, Marjorie N; Brownstein, Naomi C; Kabbaj, Mohamed

2017-02-01

Repeated intermittent exposure to ketamine has rapid and long-lasting antidepressant effects, but the abuse potential has only been assessed at high doses. Furthermore, while females are more susceptible to depression and more sensitive to ketamine's antidepressant-like effects, the abuse potential for ketamine in females is unknown. The objectives of this study are to determine the reinforcing properties of low-dose intermittent ketamine in adult rats of both sexes and determine whether cycling gonadal hormones influence females' response to ketamine. In male rats, we also aimed to determine whether reinstatement to intermittent ketamine is comparable to intermittent cocaine. Male rats intravenously self-administered cocaine (0.75 mg/kg/infusion) or ketamine (0.1 mg/kg/infusion) once every fourth day, while intact cycling female rats self-administered ketamine only during preidentified stages of their 4-day estrus cycle, when gonadal hormones are either high (proestrus) or low (diestrus). After acquiring self-administration, rats underwent daily extinction training followed by cue-primed and drug-primed reinstatement to assess drug-seeking behavior. Diestrus-trained females fail to maintain ketamine self-administration and did not display reinstatement to ketamine-paired cues. Males and proestrus-trained females reinstated to ketamine-paired cues. Ketamine-primed reinstatement was dependent on simultaneous cue presentation. Male rats reinstated to cocaine priming independent of cue presentation. These findings indicate that females's responsivity to this dose of ketamine depends on stage of cycle, as only proestrus-trained females and males respond to ketamine's reinforcing effects under this treatment paradigm.

Comparison of the effects of alfaxalone and propofol with acepromazine, butorphanol and/or doxapram on laryngeal motion and quality of examination in dogs.

PubMed

Radkey, Denise I; Hardie, Robert J; Smith, Lesley J

2018-05-01

To compare the effects of alfaxalone and propofol, with and without acepromazine and butorphanol followed by doxapram, on laryngeal motion and quality of laryngeal examination in dogs. Randomized, crossover, blinded study. Ten female Beagle dogs, aged 11-13 months and weighing 7.2-8.6 kg. The dogs were administered four intravenous (IV) treatments: alfaxalone (ALF), alfaxalone+acepromazine and butorphanol (ALF-AB), propofol (PRO) and propofol+AB (PRO-AB). AB doses were standardized. Dogs were anesthetized 5 minutes later by administration of alfaxalone or propofol IV to effect. Arytenoid motion during maximal inspiration and expiration was captured on video before and after IV doxapram (0.25 mg kg -1 ). The change in rima glottidis surface area (RGSA) was calculated to measure arytenoid motion. An investigator blinded to the treatment scored laryngeal examination quality. A 20% increase in RGSA was the minimal arytenoid motion that was detectable. RGSA was significantly less in ALF before doxapram compared with all other treatments. A <20% increase in RGSA was measured in eight of 10 dogs in PRO and in all dogs in ALF before doxapram. After doxapram, RGSA was significantly increased for PRO and ALF; however, 20% of dogs in PRO and 50% of dogs in ALF still had <20% increase in RGSA. A <20% increase in RGSA was measured in five of 10 dogs in PRO-AB and ALF-AB before doxapram. All dogs in PRO-AB and ALF-AB with <20% increase in RGSA before doxapram had ≥20% increase in RGSA after doxapram. Examination quality was significantly better in PRO-AB and ALF-AB. The use of acepromazine and butorphanol improved the quality of laryngeal examination. Any negative impact on arytenoid motion caused by these premedications was overcome with doxapram. Using either propofol or alfaxalone alone is not recommended for the evaluation of arytenoid motion. Copyright © 2018 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

Ketamine-a returning option for procedural sedation and analgesia in adults.

PubMed

O'Malley, Patricia Anne

2014-01-01

I am a clinical nurse specialist in a busy trauma center. Increasingly, we are using ketamine for procedures and pain management in adults. I thought ketamine was appropriate only for pediatric patients. Why has ketamine emerged again for adults? Also, we have seen a few cases of ketamine abuse over the past 3 months. Is ketamine abuse becoming more prevalent?

Ketamine abuse potential and use disorder.

PubMed

Liu, Yu; Lin, Deyong; Wu, Boliang; Zhou, Wenhua

2016-09-01

Ketamine is a noncompetitive antagonist of N-methyl-d-asparate (NMDA) receptor and has been long used as an anesthetic agent in humans and veterinary medicine. The present article reviews the epidemiology, pharmacology, neurochemistry, and treatment of ketamine abuse. Ketamine has a unique mood controlling property and a number of studies have demonstrated a significant and rapid antidepressant effect of ketamine. However, the therapeutic value of ketamine to treat psychiatric disorders faces a major challenge that ketamine also owns significant reinforcing and toxic effects. Its abuse has posted severe harms on individuals and society. Disrupted learning and memory processing has long been related with ketamine use. It is hypothesized that ketamine blocks NMDA receptors on gamma-aminobutyric acid (GABA) neurons inside the thalamic reticular nucleus, which leads to disinhibition of dopaminergic neurons and increased release of dopamine. Currently, there is no specific treatment for treating every ketamine patient presenting peripheral toxicity. Interestingly, ketamine psychotherapy has been suggested to be a promising approach to treat addiction of other drugs. Future research can continue to develop creative ways to investigate potential mechanism and treatments related to ketamine abuse that have posted severe individual and social harms. Copyright © 2016 Elsevier Inc. All rights reserved.

To use or not to use: an update on licit and illicit ketamine use

PubMed Central

Li, Jih-Heng; Vicknasingam, Balasingam; Cheung, Yuet-Wah; Zhou, Wang; Nurhidayat, Adhi Wibowo; Jarlais, Don C Des; Schottenfeld, Richard

2011-01-01

Ketamine, a derivative of phencyclidine that was developed in the 1960s, is an anesthetic and analgesic with hallucinogenic effects. In this paper, the pharmacological and toxicological effects of ketamine are briefly reviewed. Ketamine possesses a wide safety margin but such a therapeutic benefit is somewhat offset by its emergence phenomenon (mind-body dissociation and delirium) and hallucinogenic effects. The increasing abuse of ketamine, initially predominantly in recreational scenes to experience a “k-hole” and other hallucinatory effects but more recently also as a drug abused during the workday or at home, has further pushed governments to confine its usage in many countries. Recently, urinary tract dysfunction has been associated with long-term ketamine use. In some long-term ketamine users, such damage can be irreversible and could result in renal failure and dialysis. Although ketamine has not yet been scheduled in the United Nations Conventions, previous studies using different assessment parameters to score the overall harms of drugs indicated that ketamine may cause more harm than some of the United Nations scheduled drugs. Some countries in Southeast and East Asia have reported an escalating situation of ketamine abuse. Dependence, lower urinary tract dysfunction, and sexual impulse or violence were the most notable among the ketamine-associated symptoms in these countries. These results implied that the danger of ketamine may have been underestimated previously. Therefore, the severity levels of the ketamine-associated problems should be scrutinized more carefully and objectively. To prevent ketamine from being improperly used and evolving into an epidemic, a thorough survey on the prevalence and characteristics of illicit ketamine use is imperative so that suitable policy and measures can be taken. On the other hand, recent findings that ketamine could be useful for treating major depressive disorder has given this old drug a new impetus. If ketamine is indeed a remedy for treating depression, more research on the risks and benefits of its clinical use will be indispensable. PMID:24474851

Supercritical fluid extraction (SFE) of ketamine metabolites from dried urine and on-line quantification by supercritical fluid chromatography and single mass detection (on-line SFE-SFC-MS).

PubMed

Hofstetter, Robert; Fassauer, Georg M; Link, Andreas

2018-02-15

On-line solid-phase supercritical fluid extraction (SFE) and chromatography (SFC) coupled to mass spectrometry (MS) has been evaluated for its usefulness with respect to metabolic profiling and pharmacological investigations of ketamine in humans. The aim of this study was to develop and validate a rapid, highly selective and sensitive SFE-SFC-MS method for the quantification of ketamine and its metabolites in miniature amounts in human urine excluding liquid-liquid extraction (LLE). Several conditions were optimized systematically following the requirements of the European Medicines Agency: selectivity, carry-over, calibration curve parameters (LLOQ, range and linearity), within- and between-run accuracy and precision, dilution integrity, matrix effect, and stability. The method, which required a relatively small volume of human urine (20 μL per sample), was validated for pharmacologically and toxicologically relevant concentrations ranging from 25.0 to 1000 ng/mL (r 2  > 0.995). The lower limit of quantification (LLOQ) for all compounds was found to be as low as 0.5 ng. In addition, stability of analytes during removal of water from the urine samples using different conditions (filter paper or ISOLUTE® HM-N) was studied. In conclusion, the method developed in this study can be successfully applied to studies of ketamine metabolites in humans, and may pave the way for routine application of on-line SFE-SFC-MS in clinical investigations. Copyright © 2018 Elsevier B.V. All rights reserved.

Anesthetic Activity of Alfaxalone Compared with Ketamine in Mice

PubMed Central

Siriarchavatana, Parkpoom; Ayers, Jessica D; Kendall, Lon V

2016-01-01

Alfaxalone encased in hydroxypropyl-β-cyclodextrin is a neuroactive steroid compound that has recently been approved in the United States for use as an anesthetic in dogs and cats. We evaluated the use of alfaxalone compared with ketamine, both alone and in combination with xylazine, for anesthesia of C57BL/6 mice. We assessed time to onset of anesthesia, duration of action, reflex responses, respiratory rate, and clinical signs. Alfaxalone (80 mg/kg IP) induced a light surgical plane of anesthesia in all mice, with a time to onset of 2.2 ± 0.2 min and duration of 57.1 ± 3.8 min, whereas ketamine (80 mg/kg IP) provided only sedative effects (time to onset, 5.4 ± 0.4 min; duration, 6.9 ± 0.8 min). Clinically, alfaxalone caused a spectrum of activities, including popcorn-like jumping movements after injection, intense scratching of the face, hyperresponsiveness to noise or touch, and marked limb jerking during recovery. Adding xylazine to the single-agent protocols achieved deep surgical anesthesia (duration: alfaxalone + xylazine, 80.3 ± 17.8 min; ketamine + xylazine, 37.4 ± 8.2 min) and ameliorated the adverse clinical signs. Our preliminary analysis suggests that, because of its side effects, alfaxalone alone is not a viable anesthetic option for mice. Although alfaxalone combined with xylazine appeared to be a more viable option, some mice still experienced mild adverse reactions, and the long duration of action might be problematic regarding the maintenance of body temperature and monitoring of recovery. Further studies evaluating different routes of administration and drug combinations are warranted. PMID:27423149

Quantitative chiral and achiral determination of ketamine and its metabolites by LC-MS/MS in human serum, urine and fecal samples.

PubMed

Hasan, Mahmoud; Hofstetter, Robert; Fassauer, Georg M; Link, Andreas; Siegmund, Werner; Oswald, Stefan

2017-05-30

Ketamine (KET) is a widely used anesthetic drug which is metabolized by CYP450 enzymes to norketamine (n-KET), dehydronorketamine (DHNK), hydroxynorketamine (HNK) and hydroxyketamine (HK). Ketamine is a chiral compound and S-ketamine is known to be the more potent enantiomer. Here, we present the development and validation of three LC-MS/MS assays; the first for the quantification of racemic KET, n-KET and DHNK in human serum, urine and feces; the second for the separation and quantification of the S- and R-enantiomers of KET, n-KET and DHNK, and the third for separation and quantification of 2S,6S-hydroxynorketamine (2S,6S-HNK) and 2R,6R-hydroxynorketamine (2R,6R-HNK) in serum and urine with the ability to separate and detect 10 additional hydroxylated norketamine metabolites of racemic ketamine. Sample preparation was done by liquid-liquid extraction using methyl tert-butyl ether. For achiral determination of KET and its metabolites, an isocratic elution with ammonium acetate (pH 3.8; 5mM) and acetonitrile on a C18 column was performed. For the separation of S- and R-enantiomers of KET, n-KET and DHNK, a gradient elution was applied using a mobile phase of ammonium acetate (pH 7.5; 10mM) and isopropanol on the CHIRAL-AGP ® column. The enantioselective separation of the HNK metabolites was done on the chiral column Lux ® -Amylose-2 with a gradient method using ammonium acetate (pH 9; 5mM) and a mixture of isopropanol and acetonitrile (4:1). The mass spectrometric detection monitored for each analyte 2-3 mass/charge transitions. D4-ketamine and D4-n-KET were used as internal standards. The assays were successfully validated according to current bioanalytical guidelines and applied to a pilot study in one healthy volunteer. Compared to previously published methods, our assays have superior analytical features such as a lower amount of required matrix, faster sample preparation, shorter analytical run time and higher sensitivity (LLOQ up to 0.1ng/ml). Moreover, our assay enables for the first time the enantioselective determination of 2R,6R- and 2S,6S-HNK which were shown to be responsible for the promising antidepressant effects of ketamine. Copyright © 2017 Elsevier B.V. All rights reserved.

Suppressive effects of ketamine on macrophage functions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang Yi; Department of Anesthesiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; Chen, T.-L.

2005-04-01

Ketamine is an intravenous anesthetic agent. Clinically, induction of anesthesia with ketamine can cause immunosuppression. Macrophages play important roles in host defense. In this study, we attempted to evaluate the effects of ketamine on macrophage functions and its possible mechanism using mouse macrophage-like Raw 264.7 cells as the experimental model. Exposure of macrophages to 10 and 100 {mu}M ketamine, which correspond to 0.1 and 1 times the clinically relevant concentration, for 1, 6, and 24 h had no effect on cell viability or lactate dehydrogenase release. When the administered concentration reached 1000 {mu}M, ketamine caused a release of lactate dehydrogenasemore » and cell death. Ketamine, at 10 and 100 {mu}M, did not affect the chemotactic activity of macrophages. Administration of 1000 {mu}M ketamine in macrophages resulted in a decrease in cell migration. Treatment of macrophages with ketamine reduced phagocytic activities. The oxidative ability of macrophages was suppressed by ketamine. Treatment with lipopolysaccharide induced TNF-{alpha}, IL-1{beta}, and IL-6 mRNA in macrophages. Administration of ketamine alone did not influence TNF-{alpha}, IL-1{beta}, or IL-6 mRNA production. Meanwhile, cotreatment with ketamine and lipopolysaccharide significantly inhibited lipopolysaccharide-induced TNF-{alpha}, IL-1{beta}, and IL-6 mRNA levels. Exposure to ketamine led to a decrease in the mitochondrial membrane potential. However, the activity of mitochondrial complex I NADH dehydrogenase was not affected by ketamine. This study shows that a clinically relevant concentration of ketamine (100 {mu}M) can suppress macrophage function of phagocytosis, its oxidative ability, and inflammatory cytokine production possibly via reduction of the mitochondrial membrane potential instead of direct cellular toxicity.« less

Estimation of the contribution of norketamine to ketamine-induced acute pain relief and neurocognitive impairment in healthy volunteers

PubMed Central

Olofsen, Erik; Noppers, Ingeborg; Niesters, Marieke; Kharasch, Evan; Aarts, Leon; Sarton, Elise; Dahan, Albert

2012-01-01

Background The N-methyl-D-receptor antagonist ketamine is metabolized in the liver into its active metabolite norketamine. No human data are available on the relative contribution of norketamine to ketamine-induced analgesia and side effects. One approach to assess the ketamine and norketamine contributions is by measuring ketamine-effect at varying ketamine and norketamine plasma concentrations using the CYP450 inducer rifampicin. Methods In 12 healthy male volunteers the effect of rifampicin versus placebo pretreatment on S-ketamine (a 2-h infusion of 20 mg/h)-induced analgesia and cognition was quantified. The relative ketamine and norketamine contribution to effect was estimated using a linear additive population pharmacokinetic-pharmacodynamic model. Results S-ketamine produced significant analgesia, psychotropic effects (drug high), and cognitive impairment (including memory impairment, reduced psychomotor speed, reduced reaction time, reduced cognitive flexibility). Modeling revealed a negative contribution of S-norketamine to S-ketamine-induced analgesia and absence of contribution to cognitive impairment. At ketamine and norketamine effect concentrations of 100 ng/ml and 50 ng/ml, respectievly, the ketamine contribution to analgesia is −3.8 cm (visual analogue pain score) versus a contribution of norketamine of +1.5 cm, causing an overall effect −2.3 cm. The blood-effect-site equilibration half-life ranged from 0 (cognitive flexibility) to 11.8 (pain intensity) min, and averaged across all end-points was 6.1 min. Conclusions This first observation that norketamine produces effects in the opposite direction of ketamine requires further proof. It can explain the observation of ketamine-related excitatory phenomena (such as hyperalgesia and allodynia) upon the termination of ketamine infusions. PMID:22692377

Ketamine coadministration attenuates morphine tolerance and leads to increased brain concentrations of both drugs in the rat

PubMed Central

Lilius, T O; Jokinen, V; Neuvonen, M S; Niemi, M; Kalso, E A; Rauhala, P V

2015-01-01

Background and Purpose The effects of ketamine in attenuating morphine tolerance have been suggested to result from a pharmacodynamic interaction. We studied whether ketamine might increase brain morphine concentrations in acute coadministration, in morphine tolerance and morphine withdrawal. Experimental Approach Morphine minipumps (6 mg·day–1) induced tolerance during 5 days in Sprague–Dawley rats, after which s.c. ketamine (10 mg·kg–1) was administered. Tail flick, hot plate and rotarod tests were used for behavioural testing. Serum levels and whole tissue brain and liver concentrations of morphine, morphine-3-glucuronide, ketamine and norketamine were measured using HPLC-tandem mass spectrometry. Key Results In morphine-naïve rats, ketamine caused no antinociception whereas in morphine-tolerant rats there was significant antinociception (57% maximum possible effect in the tail flick test 90 min after administration) lasting up to 150 min. In the brain of morphine-tolerant ketamine-treated rats, the morphine, ketamine and norketamine concentrations were 2.1-, 1.4- and 3.4-fold, respectively, compared with the rats treated with morphine or ketamine only. In the liver of morphine-tolerant ketamine-treated rats, ketamine concentration was sixfold compared with morphine-naïve rats. After a 2 day morphine withdrawal period, smaller but parallel concentration changes were observed. In acute coadministration, ketamine increased the brain morphine concentration by 20%, but no increase in ketamine concentrations or increased antinociception was observed. Conclusions and Implications The ability of ketamine to induce antinociception in rats made tolerant to morphine may also be due to increased brain concentrations of morphine, ketamine and norketamine. The relevance of these findings needs to be assessed in humans. PMID:25297798

Ketamine-induced apoptosis in cultured rat cortical neurons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takadera, Tsuneo; Ishida, Akira; Ohyashiki, Takao

2006-01-15

Recent data suggest that anesthetic drugs cause neurodegeneration during development. Ketamine is frequently used in infants and toddlers for elective surgeries. The purpose of this study is to determine whether glycogen synthase kinase-3 (GSK-3) is involved in ketamine-induced apoptosis. Ketamine increased apoptotic cell death with morphological changes which were characterized by cell shrinkage, nuclear condensation or fragmentation. In addition, insulin growth factor-1 completely blocked the ketamine-induced apoptotic cell death. Ketamine decreased Akt phosphorylation. GSK-3 is known as a downstream target of Akt. The selective inhibitors of GSK-3 prevented the ketamine-induced apoptosis. Moreover, caspase-3 activation was accompanied by the ketamine-induced cellmore » death and inhibited by the GSK-3 inhibitors. These results suggest that activation of GSK-3 is involved in ketamine-induced apoptosis in rat cortical neurons.« less

Ketamine and international regulations.

PubMed

Liao, Yanhui; Tang, Yi-Lang; Hao, Wei

2017-09-01

Ketamine is an anesthetic commonly used in low-income countries and has recently been shown to be effective for treatment-resistant depression. However, the illicit manufacturing, trafficking, and nonmedical use of ketamine are increasing globally, and its illicit use poses major public health challenges in many countries. To review the nonmedical use of ketamine in selected countries and its regulatory control. We conducted a review of literature identified from searches of the China National Knowledge Infrastructure (CNKI) (1979-2016) and PubMed databases, supplemented by additional references identified by the authors. Special attention was given to the regulation of ketamine. Illicit manufacturing, trafficking, and use of ketamine appear to have begun on a large scale in several Asian nations, and it has subsequently spread to other regions. Regulations governing availability of ketamine vary across countries, but there is a clear trend toward tighter regulations. As nonmedical use of ketamine and its harmful consequences have worsened globally, stricter controls are necessary. Appropriate regulation of ketamine is important for international efforts to control ketamine's cross-border trafficking and its nonmedical use.

Previous Ketamine Produces an Enduring Blockade of Neurochemical and Behavioral Effects of Uncontrollable Stress

PubMed Central

Dolzani, Samuel D.; Tilden, Scott; Christianson, John P.; Kubala, Kenneth H.; Bartholomay, Kristi; Sperr, Katherine; Ciancio, Nicholas; Watkins, Linda R.; Maier, Steven F.

2016-01-01

Recent interest in the antidepressant and anti-stress effects of subanesthetic doses of ketamine, an NMDA receptor antagonist, has identified mechanisms whereby ketamine reverses the effect of stress, but little is known regarding the prophylactic effect ketamine might have on future stressors. Here we investigate the prophylactic effect of ketamine against neurochemical and behavioral changes that follow inescapable, uncontrollable tail shocks (ISs) in Sprague Dawley rats. IS induces increased anxiety, which is dependent on activation of serotonergic (5-HT) dorsal raphe nucleus (DRN) neurons that project to the basolateral amygdala (BLA). Ketamine (10 mg/kg, i.p.) administered 2 h, 1 week, or 2 weeks before IS prevented the increased extracellular levels of 5-HT in the BLA typically produced by IS. In addition, ketamine administered at these time points blocked the decreased juvenile social investigation produced by IS. Microinjection of ketamine into the prelimbic (PL) region of the medial prefrontal cortex duplicated the effects of systemic ketamine, and, conversely, systemic ketamine effects were prevented by pharmacological inhibition of the PL. Although IS does not activate DRN-projecting neurons from the PL, IS did so after ketamine, suggesting that the prophylactic effect of ketamine is a result of altered functioning of this projection. SIGNIFICANCE STATEMENT The reported data show that systemic ketamine, given up to 2 weeks before a stressor, blunts behavioral and neurochemical effects of the stressor. The study also advances understanding of the mechanisms involved and suggests that ketamine acts at the prelimbic cortex to sensitize neurons that project to and inhibit the DRN. PMID:26740657

The effects of ketamine on sexual behavior, anxiety, and locomotion in female rats.

PubMed

Guarraci, Fay A; Gonzalez, Chantal M F; Lucero, Devon; Womble, Paige D; Abdel-Rahim, Heba; DeVore, Jennie; Kunkel, Marcela Nicole; Quadlander, Emma; Stinnett, Morgan; Boyette-Davis, Jessica

2018-02-01

The present study characterized the effects of ketamine on sexual behavior and anxiety in female rats. In Experiment 1, female subjects received an injection of ketamine (10.0mg/kg) or saline 30min prior to a sexual partner-preference test during which each female subject was given the opportunity to interact with a female stimulus or a sexually vigorous male stimulus. Immediately afterwards, female subjects were tested for locomotion in an open field test. Ketamine-treated subjects spent significantly more time with the male stimulus than saline-treated subjects. No other measures of mating behavior (i.e., paced mating behavior, lordosis) were affected by ketamine. Ketamine also had no effect on locomotion. In Experiment 2, female subjects received an injection of ketamine (10.0mg/kg), or saline daily for 10days to investigate the possibility that sexual dysfunction emerges only after repeated exposure. Similar to the results of Experiment 1, ketamine-treated subjects spent significantly more time with the male stimulus than saline-treated subjects. Chronic ketamine treatment also decreased the likelihood of leaving the male after mounts, without affecting any other measures of sexual behavior. Chronic ketamine had no effect on locomotion. In Experiment 3, female subjects received an injection of ketamine (10.0mg/kg) or saline and were tested for anxiety in an elevated plus maze test and for locomotion in an open field test. Acute ketamine had no effect on anxiety or locomotion. In Experiment 4, female subjects received an injection of ketamine (10.0mg/kg) or saline daily for 10days to investigate the possibility that anxiety emerges only after repeated exposure. Chronic ketamine exposure had no effect on any measure of anxiety. However, chronic ketamine exposure increased locomotion. The results from these experiments indicate that unlike other medications prescribed for depression, neither acute nor chronic ketamine treatment causes anxiety or disruption of sexual behavior. Copyright © 2018 Elsevier Inc. All rights reserved.

21 CFR 522.1222 - Ketamine.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ketamine. 522.1222 Section 522.1222 Food and Drugs..., AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222 Ketamine. (a) Specifications. Each milliliter contains ketamine hydrochloride equivalent to 100 milligrams (mg) ketamine base...

21 CFR 522.1223 - Ketamine, promazine, and aminopentamide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ketamine, promazine, and aminopentamide. 522.1223... § 522.1223 Ketamine, promazine, and aminopentamide. (a) Specifications. Each milliliter of solution contains ketamine hydrochloride equivalent to 100 milligrams (mg) ketamine base activity, 7.5 (mg) of...

The prevalence and natural history of urinary symptoms among recreational ketamine users.

PubMed

Winstock, Adam R; Mitcheson, Luke; Gillatt, David A; Cottrell, Angela M

2012-12-01

Study Type--Symptom prevalence (prospective cohort) Level of Evidence 1b. What's known on the subject? and What does the study add? Case series have described lower urinary tract symptoms associated with ketamine use including severe pain, frequency, haematuria and dysuria. Little is known regarding the frequency of symptoms, relationship of symptoms with dose and frequency of use and natural history of symptoms once the ketamine user has stopped. This study describes the prevalence of ketamine use in a population of recreational drug users in a dance music setting. It shows a dose-frequency relationship with ketamine use. It shows that urinary symptoms associated with recreational ketamine use may lead to a considerable demand on health resources in the primary-, secondary- and emergency-care settings. It shows that symptoms may improve once ketamine use is decreased. • To investigate the prevalence and natural history of urinary symptoms in a cohort of recreational ketamine users. • A purposeful sampling technique was used. • Between November 2009 and January 2010 participants were invited to undertake an on-line questionnaire promoted by a national dance music magazine and website. • Data regarding demographics and illicit drug-use were collected. • Among respondents reporting recent ketamine use, additional information detailing their ketamine use, experience of urinary symptoms and use of related healthcare services was obtained. • In all, 3806 surveys were completed, of which 1285 (33.8%) participants reported ketamine use within the last year. • Of the ketamine users, 17% were found to be dependent on the drug; 26.6% (340) of recent ketamine users reported experiencing urinary symptoms. • Urinary symptoms were significantly related to both dose of ketamine used and frequency of ketamine use. • Of 251 users reporting their experience of symptoms over time in relationship to their use of ketamine, 51% reported improvement in urinary symptoms upon cessation of use with only eight (3.8%) reporting deterioration after stopping use. • Urinary tract symptoms are reported in over a quarter of regular ketamine users. • A dose and frequency response relationship has been shown between ketamine use and urinary symptoms. • Both users and primary-care providers need to be educated about urinary symptoms that may arise in ketamine users. A multi-disciplinary approach promoting harm reduction, cessation and early referral is needed to manage individuals with ketamine-associated urinary tract symptoms to avoid progression to severe and irreversible urological pathologies. © 2012 BJU INTERNATIONAL.

Subanesthetic, Subcutaneous Ketamine Infusion Therapy in the Treatment of Chronic Nonmalignant Pain.

PubMed

Zekry, Olfat; Gibson, Stephen B; Aggarwal, Arun

2016-06-01

This study was designed to describe the efficacy and toxicity of subcutaneous ketamine infusions and sublingual ketamine lozenges for the treatment of chronic nonmalignant pain. Data were collected prospectively on 70 subjects managed in an academic, tertiary care hospital between 2007 and 2012 who received between 3 and 7 days of subanesthetic, subcutaneous ketamine infusion. Data were analyzed for efficacy, adverse effects, and reduction in use of opioid medication. We also analyzed whether subsequent treatment with sublingual ketamine lozenges resulted in longer-term efficacy of the beneficial effects of the initial ketamine infusion. There was a significant reduction in pain intensity measured by numerical rating scale (NRS) from mean of 6.38 before ketamine to 4.60 after ketamine (P < .005) that was sustained for between 3 months and 6 years. In subjects on opioids, there was a significant reduction in opioid use at the end of the ketamine infusion from a mean morphine equivalent dose (MMED) of 216 mg/day before ketamine to 89 mg/day after ketamine (P < .005). The overall reduction in opioid use after ketamine infusion was 59%. No subjects increased their use of opioids during their hospitalization for the ketamine infusion. A small proportion of subjects who responded to the infusion were continued on ketamine lozenges. This group was followed for between 3 months and 2 years. The use of ketamine lozenges after the infusion resulted in 31% of these subjects being able to cease their use of opioids compared with only 6% who did not receive ketamine lozenges. Eleven percent of subjects who received lozenges subsequently increased their opioid usage. Adverse effects were fairly common, but only mild, with 46% of patients experiencing light-headedness and dizziness, 25% tiredness and sedation, 12% headaches, 12% hallucinations, and 8% vivid dreams. Adverse effects were easily managed by reducing the rate of the ketamine infusion. The administration of subanesthetic, subcutaneous ketamine infusion was well tolerated, with mostly mild adverse effects and no serious adverse effects. The infusion provided significant pain relief in subjects who had failed a wide range of pharmacological and cognitive behavioral therapies. In addition, the results indicate that sublingual ketamine lozenges offer a promising therapeutic option for longer-term relief of chronic nonmalignant pain. The ketamine lozenges have been shown to have acceptable storage stability, and the sublingual bioavailability is sufficiently high and reproducible to support its use in this context.

Effects of ketamine on glucose uptake by glucose transporter type 3 expressed in Xenopus oocytes: The role of protein kinase C

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tomioka, Shigemasa, E-mail: tomioka@dent.tokushima-u.ac.jp; Kaneko, Miyuki; Satomura, Kazuhito

2009-10-09

We investigated the effects of ketamine on the type 3 facilitative glucose transporter (GLUT3), which plays a major role in glucose transport across the plasma membrane of neurons. Human-cloned GLUT3 was expressed in Xenopus oocytes by injection of GLUT3 mRNA. GLUT3-mediated glucose uptake was examined by measuring oocyte radioactivity following incubation with 2-deoxy-D-[1,2-{sup 3}H]glucose. While ketamine and S(+)-ketamine significantly increased GLUT3-mediated glucose uptake, this effect was biphasic such that higher concentrations of ketamine inhibited glucose uptake. Ketamine (10 {mu}M) significantly increased V{sub max} but not K{sub m} of GLUT3 for 2-deoxy-D-glucose. Although staurosporine (a protein kinase C inhibitor) increased glucosemore » uptake, no additive or synergistic interactions were observed between staurosporine and racemic ketamine or S(+)-ketamine. Treatment with ketamine or S(+)-ketamine partially prevented GLUT3 inhibition by the protein kinase C activator phorbol-12-myrisate-13-acetate. Our results indicate that ketamine increases GLUT3 activity at clinically relevant doses through a mechanism involving PKC inhibition.« less

Betaine enhances antidepressant-like, but blocks psychotomimetic effects of ketamine in mice.

PubMed

Lin, Jen-Cheng; Lee, Mei-Yi; Chan, Ming-Huan; Chen, Yi-Chyan; Chen, Hwei-Hsien

2016-09-01

Ketamine is emerging as a new hope against depression, but ketamine-associated psychotomimetic effects limit its clinical use. An adjunct therapy along with ketamine to alleviate its adverse effects and even potentiate the antidepressant effects might be an alternative strategy. Betaine, a methyl derivative of glycine and a dietary supplement, has been shown to have antidepressant-like effects and to act like a partial agonist at the glycine site of N-methyl-D-aspartate receptors (NMDARs). Accordingly, betaine might have potential to be an adjunct to ketamine treatment for depression. The antidepressant-like effects of ketamine and betaine were evaluated by forced swimming test and novelty suppressed feeding test in mice. Both betaine and ketamine produced antidepressant-like effects. Furthermore, we determined the effects of betaine on ketamine-induced antidepressant-like and psychotomimetic behaviors, motor incoordination, hyperlocomotor activity, and anesthesia. The antidepressant-like responses to betaine combined with ketamine were stronger than their individual effects. In contrast, ketamine-induced impairments in prepulse inhibition, novel object recognition test, social interaction, and rotarod test were remarkably attenuated, whereas ketamine-induced hyperlocomotion and loss of righting reflex were not affected by betaine. These findings revealed that betaine could enhance the antidepressant-like effects, yet block the psychotomimetic effects of ketamine, suggesting that betaine can be considered as an add-on therapy to ketamine for treatment-resistant depression and suitable for the treatment of depressive symptoms in patients with schizophrenia.

Systemic ketamine inhibits hypersensitivity after surgery via descending inhibitory pathways in rats.

PubMed

Koizuka, Shiro; Obata, Hideaki; Sasaki, Masayuki; Saito, Shigeru; Goto, Fumio

2005-05-01

Systemic ketamine suppresses several types of chronic pain. Although ketamine is used as a general anesthetic agent, the analgesic effect of systemic ketamine for early-stage postoperative pain is not clear. We investigated the efficacy and mechanism of systemic ketamine in a rat model of postoperative pain. An incision was made in the plantar aspect of the left hind paw in male Wistar rats. Mechanical hypersensitivity was measured using calibrated von Frey filaments. The anti-hypersensitivity effect of systemic or intrathecal administration of ketamine was determined every hour after making the incision. We examined the effects of intrathecal pretreatment with yohimbine, an alpha2-adrenoceptor antagonist, and methysergide, a serotonergic receptor antagonist, on the anti-hypersensitivity effect of ketamine. We also examined the effect of systemic ketamine on the c-fos immunoreactivity in the spinal cord. Systemic administration of ketamine at doses from 3 to 30 mg.kg(-1) produced anti-hypersensitivity effects in a dose-dependent manner. Intrathecal administration of ketamine had no effect. There was no significant difference between effects of pre- and post-incisional administration. Intrathecal pretreatment with yohimbine (10 microg) or methysergide (15 microg) completely reversed the anti-hypersensitivity effects of systemic ketamine. Systemic ketamine reduced fos expression in laminae I-II in the dorsal horn of the lumbar spinal cord ipsilateral to the paw incision. The results suggest that systemic administration of ketamine perioperatively suppresses early-stage postoperative pain via monoaminergic descending inhibitory pathways.

Oral ketamine for the treatment of pain and treatment-resistant depression†.

PubMed

Schoevers, Robert A; Chaves, Tharcila V; Balukova, Sonya M; Rot, Marije Aan Het; Kortekaas, Rudie

2016-02-01

Recent studies with intravenous (i.v.) application of ketamine show remarkable but short-term success in patients with MDD. Studies in patients with chronic pain have used different ketamine applications for longer time periods. This experience may be relevant for psychiatric indications. To review the literature about the dosing regimen, duration, effects and side-effects of oral, intravenous, intranasal and subcutaneous routes of administration of ketamine for treatment-resistant depression and pain. Searches in PubMed with the terms 'oral ketamine', 'depression', 'chronic pain', 'neuropathic pain', 'intravenous ketamine', 'intranasal ketamine' and 'subcutaneous ketamine' yielded 88 articles. We reviewed all papers for information about dosing regimen, number of individuals who received ketamine, number of ketamine days per study, results and side-effects, as well as study quality. Overall, the methodological strength of studies investigating the antidepressant effects of ketamine was considered low, regardless of the route of administration. The doses for depression were in the lower range compared with studies that investigated analgesic use. Studies on pain suggested that oral ketamine may be acceptable for treatment-resistant depression in terms of tolerability and side-effects. Oral ketamine, given for longer time periods in the described doses, appears to be well tolerated, but few studies have systematically examined the longer-term negative consequences. The short- and longer-term depression outcomes as well as side-effects need to be studied with rigorous randomised controlled trials. © The Royal College of Psychiatrists 2016.

Single-dose infusion ketamine and non-ketamine N-methyl-d-aspartate receptor antagonists for unipolar and bipolar depression: a meta-analysis of efficacy, safety and time trajectories.

PubMed

Kishimoto, T; Chawla, J M; Hagi, K; Zarate, C A; Kane, J M; Bauer, M; Correll, C U

2016-05-01

Ketamine and non-ketamine N-methyl-d-aspartate receptor antagonists (NMDAR antagonists) recently demonstrated antidepressant efficacy for the treatment of refractory depression, but effect sizes, trajectories and possible class effects are unclear. We searched PubMed/PsycINFO/Web of Science/clinicaltrials.gov until 25 August 2015. Parallel-group or cross-over randomized controlled trials (RCTs) comparing single intravenous infusion of ketamine or a non-ketamine NMDAR antagonist v. placebo/pseudo-placebo in patients with major depressive disorder (MDD) and/or bipolar depression (BD) were included in the analyses. Hedges' g and risk ratios and their 95% confidence intervals (CIs) were calculated using a random-effects model. The primary outcome was depressive symptom change. Secondary outcomes included response, remission, all-cause discontinuation and adverse effects. A total of 14 RCTs (nine ketamine studies: n = 234; five non-ketamine NMDAR antagonist studies: n = 354; MDD = 554, BD = 34), lasting 10.0 ± 8.8 days, were meta-analysed. Ketamine reduced depression significantly more than placebo/pseudo-placebo beginning at 40 min, peaking at day 1 (Hedges' g = -1.00, 95% CI -1.28 to -0.73, p < 0.001), and loosing superiority by days 10-12. Non-ketamine NMDAR antagonists were superior to placebo only on days 5-8 (Hedges' g = -0.37, 95% CI -0.66 to -0.09, p = 0.01). Compared with placebo/pseudo-placebo, ketamine led to significantly greater response (40 min to day 7) and remission (80 min to days 3-5). Non-ketamine NMDAR antagonists achieved greater response at day 2 and days 3-5. All-cause discontinuation was similar between ketamine (p = 0.34) or non-ketamine NMDAR antagonists (p = 0.94) and placebo. Although some adverse effects were more common with ketamine/NMDAR antagonists than placebo, these were transient and clinically insignificant. A single infusion of ketamine, but less so of non-ketamine NMDAR antagonists, has ultra-rapid efficacy for MDD and BD, lasting for up to 1 week. Development of easy-to-administer, repeatedly given NMDAR antagonists without risk of brain toxicity is of critical importance.

Ketamine for the Acute Management of Excited Delirium and Agitation in the Prehospital Setting.

PubMed

Linder, Lauren M; Ross, Clint A; Weant, Kyle A

2018-01-01

Traditional first-line therapy in the prehospital setting for the acutely agitated patient includes an antipsychotic in combination with a benzodiazepine. Recently, interest has grown regarding the use of ketamine in the prehospital setting as an attempt to overcome the limitations of the traditional medications and provide a more safe and effective therapy. This review provides an overview of the pharmacology of ketamine, evaluates the literature regarding ketamine use for prehospital agitation, and proposes an algorithm that may be used within the prehospital setting. A literature review was conducted to identify articles utilizing ketamine in the prehospital setting. The review was limited to English-language articles identified in Embase (1988-June 2017) and the U.S. National Library of Medicine (1970-June 2017). References of all pertinent articles were also reviewed. Ten articles were identified including 418 patients receiving ketamine for agitation. The most commonly utilized route for administration was intramuscular (IM), with five of the seven IM administration studies using a ketamine dose of 5 mg/kg. Ketamine administered in this fashion was efficacious to achieve proper sedation during transport and did not require repeat dosing. Three studies applied a ketamine protocol to outline dosing and the management of ketamine adverse events. The most common adverse events identified were respiratory-related events and hypersalivation. Ketamine has a role for agitation management in the prehospital setting; however, emergency personnel education and ketamine protocols should be utilized to aid in safe and effective pharmacotherapy and provide guidance on the management of adverse events. Future prospective comparative studies, with protocolized standard ketamine regimens, are needed to further delineate the role of ketamine in agitation management and identify accurate adverse event incidence rates. © 2017 Pharmacotherapy Publications, Inc.

Ketamine produces lasting disruptions in encoding of sensory stimuli.

PubMed

Maxwell, Christina R; Ehrlichman, Richard S; Liang, Yuling; Trief, Danielle; Kanes, Stephen J; Karp, Jonathan; Siegel, Steven J

2006-01-01

The current study analyzed the acute, chronic, and lasting effects of ketamine administration in four inbred mouse strains (C3H/HeHsd, C57BL/6Hsd, FVB/Hsd, and DBA/2Hsd) to evaluate vulnerability to ketamine as a drug of abuse and as a model of schizophrenia. Serum half-life of ketamine was similar between all strains (approximately 13 min). Also, the ratio of brain-to-serum ketamine levels was 3:1. Examination of multiple phases of auditory processing using auditory-evoked potentials (AEPs) following acute ketamine (0, 5, and 20 mg/kg) treatment revealed C3H/HeHsd mice to be most vulnerable to ketamine-induced alterations in AEPs, whereas FVB/Hsd mice exhibited the least electrophysiological sensitivity to ketamine. Overall, the precortical P1-evoked potential component increased in amplitude and latency, whereas the cortically generated N1 and P2 components decreased in amplitude and latency following acute ketamine across all strains. Brain catecholamine analyses indicated that ketamine decreased hippocampus epinephrine levels in C3H/HeHsd but elevated hippocampus epinephrine levels in FVB/Hsd, suggesting one potential mechanism for AEP vulnerability to ketamine. Based on results of the acute study, the immediate and lasting effects of chronic low-dose ketamine on AEPs were examined among C3H/HeHsd (sensitive) and FVB/Hsd (insensitive) mice. We observed a decrement of the N1 amplitude that persisted at least 1 week after the last exposure to ketamine across both strains. This lasting deficit in information processing occurred in the absence of acute changes among the FVB/Hsd mice. Implications for both ketamine abuse and N-methyl-D-aspartate hypofunction models of schizophrenia are discussed.

Other drug use does not impact cognitive impairments in chronic ketamine users.

PubMed

Zhang, Chenxi; Tang, Wai Kwong; Liang, Hua Jun; Ungvari, Gabor Sandor; Lin, Shih-Ku

2018-05-01

Ketamine abuse causes cognitive impairments, which negatively impact on users' abstinence, prognosis, and quality of life. of cognitive impairments in chronic ketamine users have been inconsistent across studies, possibly due to the small sample sizes and the confounding effects of concomitant use of other illicit drugs. This study investigated the cognitive impairment and its related factors in chronic ketamine users with a large sample size and explored the impact of another drug use on cognitive functions. Cognitive functions, including working, verbal and visual memory and executive functions were assessed in ketamine users: 286 non-heavy other drug users and 279 heavy other drug users, and 261 healthy controls. Correlations between cognitive impairment and patterns of ketamine use were analysed. Verbal and visual memory were impaired, but working memory and executive functions were intact for all ketamine users. No significant cognitive differences were found between the two ketamine groups. Greater number of days of ketamine use in the past month was associated with worse visual memory performance in non-heavy other drug users. Higher dose of ketamine use was associated with worse short-term verbal memory in heavy other drug users. Verbal and visual memory are impaired in chronic ketamine users. Other drug use appears to have no impact on ketamine users' cognitive performance. Copyright © 2018. Published by Elsevier B.V.

Ketamine

MedlinePlus

... Staying Safe Videos for Educators Search English Español Ketamine KidsHealth / For Teens / Ketamine Print en español Ketamina What It Is: Ketamine hydrochloride is a quick-acting anesthetic that is ...

Molecular recognition of ketamine by a subset of olfactory G protein–coupled receptors

PubMed Central

Saven, Jeffery G.; Matsunami, Hiroaki; Eckenhoff, Roderic G.

2015-01-01

Ketamine elicits various neuropharmacological effects, including sedation, analgesia, general anesthesia, and antidepressant activity. Through an in vitro screen, we identified four mouse olfactory receptors (ORs) that responded to ketamine. In addition to their presence in the olfactory epithelium, these G protein (heterotrimeric guanine nucleotide–binding protein)–coupled receptors (GPCRs) are distributed throughout the central nervous system. To better understand the molecular basis of the interactions between ketamine and ORs, we used sequence comparison and molecular modeling to design mutations that (i) increased, reduced, or abolished ketamine responsiveness in responding receptors, and (ii) rendered non-responding receptors responsive to ketamine. We showed that olfactory sensory neurons (OSNs) that expressed distinct ORs responded to ketamine in vivo, suggesting that ORs may serve as functional targets for ketamine. The ability to both abolish and introduce responsiveness to ketamine in GPCRs enabled us to identify and confirm distinct interaction loci in the binding site, which suggested a signature ketamine-binding pocket that may guide exploration of additional receptors for this general anesthetic drug. PMID:25829447

[Safety and efficacy of ketamine for pain relief].

PubMed

Niesters, Marieke; Dahan, Albert; van Kleef, Maarten

2016-01-01

Intravenous ketamine treatment is frequently used for the management of chronic pain, especially in those patients who do not benefit from other therapies. In this commentary we discuss the efficacy of ketamine for relief of chronic pain and ketamine's safety profile. A review of the literature indicates that only a few studies show that intravenous ketamine has analgesic effects that persist beyond the infusion period, an effect that occurs in about two-thirds of patients. Ketamine has multiple safety issues, ranging from psychotomimetic and schizotypal symptoms, sympathetic stimulation, tachycardia and hypertension, and damage to the liver and the urogenital tract. Damage to the urogenital tract seems to be restricted to individuals who chronically abuse ketamine. We indicate the need for large randomized trials in which ketamine is compared with an 'active' placebo.

Glutamate Receptor Antagonists as Fast-Acting Therapeutic Alternatives for the Treatment of Depression: Ketamine and Other Compounds

PubMed Central

Niciu, Mark J.; Henter, Ioline D.; Luckenbaugh, David A.; Zarate, Carlos A.; Charney, Dennis S.

2014-01-01

The N-methyl-d-aspartate (NMDA) receptor antagonist ketamine has rapid and potent antidepressant effects in treatment-resistant major depressive disorder and bipolar depression. These effects are in direct contrast to the more modest effects seen after weeks of treatment with classic monoaminergic antidepressants. Numerous open-label and case studies similarly validate ketamine’s antidepressant properties. These clinical findings have been reverse-translated into preclinical models in an effort to elucidate ketamine’s antidepressant mechanism of action, and three important targets have been identified: mammalian target of rapamycin (mTOR), eukaryotic elongation factor 2 (eEF2), and glycogen synthase kinase-3 (GSK-3). Current clinical and preclinical research is focused on (a) prolonging/maintaining ketamine’s antidepressant effects, (b) developing more selective NMDA receptor antagonists free of ketamine’s adverse effects, and (c) identifying predictor, mediator/moderator, and treatment response biomarkers of ketamine’s antidepressant effects. PMID:24392693

Can psychedelic compounds play a part in drug dependence therapy?

PubMed

Sessa, Ben; Johnson, Matthew W

2015-01-01

After a 40-year hiatus there is now a revisiting of psychedelic drug therapy throughout psychiatry, with studies examining the drugs psilocybin, ketamine, ibogaine and ayahuasca in the treatment of drug dependence. Limitations to these therapies are both clinical and legal, but the possibility of improving outcomes for patients with substance dependency imposes an obligation to research this area. Royal College of Psychiatrists.

Ketamine Alters Hippocampal Cell Proliferation and Improves Learning in Mice after Traumatic Brain Injury.

PubMed

Peters, Austin J; Villasana, Laura E; Schnell, Eric

2018-04-30

Traumatic brain injury induces cellular proliferation in the hippocampus, which generates new neurons and glial cells during recovery. This process is regulated by N-methyl-D-aspartate-type glutamate receptors, which are inhibited by ketamine. The authors hypothesized that ketamine treatment after traumatic brain injury would reduce hippocampal cell proliferation, leading to worse behavioral outcomes in mice. Traumatic brain injury was induced in mice using a controlled cortical impact injury, after which mice (N = 118) received either ketamine or vehicle systemically for 1 week. The authors utilized immunohistochemical assays to evaluate neuronal, astroglial, and microglial cell proliferation and survival 3 days, 2 weeks, and 6 weeks postintervention. The Morris water maze reversal task was used to assess cognitive recovery. Ketamine dramatically increased microglial proliferation in the granule cell layer of the hippocampus 3 days after injury (injury + vehicle, 2,800 ± 2,700 cells/mm, n = 4; injury + ketamine, 11,200 ± 6,600 cells/mm, n = 6; P = 0.012). Ketamine treatment also prevented the production of astrocytes 2 weeks after injury (sham + vehicle, 2,400 ± 3,200 cells/mm, n = 13; injury + vehicle, 10,500 ± 11,300 cells/mm, n = 12; P = 0.013 vs. sham + vehicle; sham + ketamine, 3,500 ± 4,900 cells/mm, n = 14; injury + ketamine, 4,800 ± 3,000 cells/mm, n = 13; P = 0.955 vs. sham + ketamine). Independent of injury, ketamine temporarily reduced neurogenesis (vehicle-exposed, 105,100 ± 66,700, cells/mm, n = 25; ketamine-exposed, 74,300 ± 29,200 cells/mm, n = 27; P = 0.031). Ketamine administration improved performance in the Morris water maze reversal test after injury, but had no effect on performance in sham-treated mice. Ketamine alters hippocampal cell proliferation after traumatic brain injury. Surprisingly, these changes were associated with improvement in a neurogenesis-related behavioral recall task, suggesting a possible benefit from ketamine administration after traumatic brain injury in mice. Future studies are needed to determine generalizability and mechanism.

Metaplastic Effects of Subanesthetic Ketamine on CA1 Hippocampal Function

PubMed Central

Izumi, Yukitoshi; Zorumski, Charles F.

2014-01-01

Ketamine is a non-competitive N-methyl-D-aspartate receptor (NMDAR) antagonist of interest in neuropsychiatry. In the present studies, we examined the effects of subanesthetic, low micromolar ketamine on excitatory postsynaptic potentials (EPSPs), population spikes (PSs) and synaptic plasticity in the CA1 region of rat hippocampal slices. Ketamine acutely inhibited NMDAR-mediated synaptic responses with half-maximal effects near 10 µM. When administered for 15–30 min at 1–10 µM, ketamine had no effect on baseline dendritic AMPA receptor-mediated EPSPs, but persistently enhanced somatic EPSPs in the pyramidal cell body layer and augmented PS firing. Acute low micromolar ketamine also had no effect on the induction of long-term potentiation (LTP) but blocked long-term depression (LTD). Following 30 min administration of 1–10 µM ketamine, however, a slowly developing and persistent form of LTP inhibition was observed that took two hours following ketamine washout to become manifest. This LTP inhibition did not result from prolonged or enhanced NMDAR inhibition during drug washout. Effects of low ketamine on somatic EPSPs and LTP were not mimicked by a high ketamine concentration that completely inhibited NMDARs, and both of these effects were blocked by co-administration of low ketamine with a low concentration of the competitive NMDAR antagonist, 2-amino-5-phosphonovalerate or inhibitors of nitric oxide synthase. These results indicate that concentrations of ketamine relevant to psychotropic and psychotomimetic effects have complex metaplastic effects on hippocampal function that involve activation of unblocked NMDARs during ketamine exposure. PMID:25128848

[Ketamine as anesthetic agent in electroconvulsion therapy].

PubMed

Janke, C; Bumb, J M; Aksay, S S; Thiel, M; Kranaster, L; Sartorius, A

2015-05-01

Electroconvulsive therapy (ECT) is a well-established, safe and effective treatment for severe psychiatric disorders. Ketamine is known as a core medication in anesthesiology and has recently gained interest in ECT practice as there are three potential advantages: (1) ketamine has no anticonvulsive actions, (2) according to recent studies ketamine could possess a unique intrinsic antidepressive potential and (3) ketamine may exhibit neuroprotective properties, which again might reduce the risk of cognitive side effects associated with ECT. The use of ketamine in psychiatric patients has been controversially discussed due to its dose-dependent psychotropic and psychotomimetic effects. This study was carried out to test if the occurrence of side effects is comparable and if seizure quality is better with ketamine when compared to thiopental. This retrospective study analyzed a total of 199 patients who received ketamine anesthesia for a total of 2178 ECT sessions. This cohort was compared to patients who were treated with thiopental for 1004 ECT sessions. A repeated measurement multiple logistic regression analysis revealed significant advantages in the ketamine group for seizure concordance and postictal suppression (both are surrogates for central inhibition). S-ketamin also necessitated the use of a higher dose of urapidil and a higher maximum postictal heart frequency. Clinically relevant psychiatric side effects were rare in both groups. No psychiatric side effects occurred in the subgroup of patients with schizophrenia (ketamine: n = 30). The mean dose of S-ketamine used increased in the first years but stabilized at 63 mg per patient in 2014. From these experiences it can be concluded that S-ketamine can be recommended at least as a safe alternative to barbiturates.

Use of Ketamine in Elderly Patients with Treatment-Resistant Depression.

PubMed

Medeiros da Frota Ribeiro, Carolina; Riva-Posse, Patricio

2017-11-15

The purpose of this paper is to provide a review of the use of ketamine as an antidepressant for treatment-resistant depression (TRD) in the geriatric population. Available treatment options for late-life treatment-resistant depression are limited and include electroconvulsive therapy and transcranial magnetic stimulation as well as possible pharmacologic augmentation. Ketamine has been shown to be a promising treatment in TRD; however, data regarding the use of ketamine in the elderly includes only five case reports. We discuss the use of ketamine for late-life TRD and present two cases where ketamine led to a significant and sustained improvement in depressive symptoms. Ketamine is a promising treatment for geriatric patients with TRD. Further studies in the elderly will provide valuable insights into the use of ketamine for a population much in need of safe and effective treatments for TRD.

Intact urothelial barrier function in a mouse model of ketamine-induced voiding dysfunction

PubMed Central

Rajandram, Retnagowri; Ong, Teng Aik; Razack, Azad H. A.; MacIver, Bryce; Zeidel, Mark

2016-01-01

Ketamine is a popular choice for young drug abusers. Ketamine abuse causes lower urinary tract symptoms, with the underlying pathophysiology poorly understood. Disruption of urothelial barrier function has been hypothesized to be a major mechanism for ketamine cystitis, yet the direct evidence of impaired urothelial barrier function is still lacking. To address this question, 8-wk-old female C57BL/6J mice were injected intraperitoneally with 30 mg·kg−1·day−1 ketamine for 12 wk to induce ketamine cystitis. A spontaneous voiding spot assay showed that ketamine-treated mice had increased primary voiding spot numbers and smaller primary voiding spot sizes than control mice (P < 0.05), indicating a contracted bladder and bladder overactivity. Consistently, significantly increased voiding frequency was observed in ketamine-treated mice on cystometrograms. These functional experiments indicate that ketamine induces voiding dysfunction in mice. Surprisingly, urothelial permeability in ketamine-treated mice was not changed when measured using an Ussing chamber system with isotopic urea and water. Mouse urothelial structure was also not altered, and intact umbrella cell structure was observed by both transmission and scanning electron microscopy. Furthermore, immunostaining and confocal microscopy confirmed the presence of a well-defined distribution of zonula occuldens-1 in tight junctions and uroplakin in umbrella cells. In conclusion, these data indicate that ketamine injection induces voiding dysfunction in mice but does not necessarily disrupt mouse bladder barrier function. Disruption of urothelial barrier function may not be the major mechanism in ketamine cystitis. PMID:26911853

Targeting oxidative stress, acetylcholinesterase, proinflammatory cytokine, dopamine and GABA by eucalyptus oil (Eucalyptus globulus) to alleviate ketamine-induced psychosis in rats.

PubMed

Yadav, Monu; Jindal, Deepak Kumar; Parle, Milind; Kumar, Anil; Dhingra, Sameer

2018-02-20

Essential oil of eucalyptus species is among the most common traded essential oils in the world. There is an increasing interest in the application of eucalyptus oil as a natural additive in food and pharmaceutical industry. The present study was undertaken to identify the phytoconstituents present in the essential oil of Eucalyptus globulus leaves (EO) and ascertain their protective effect against ketamine-induced psychosis in rats. GC-MS technique was used for analysis of phytoconstituents present in EO. Ketamine (50 mg/kg, i.p.) was used to induce psychosis in rats. Photoactometer, forced swim test and pole climb avoidance test were used to evaluate the protective effects of the EO (500, 1000 and 2000 mg/kg, p.o.) on acute and chronic administration. Bar test was used to test the side effect of EO. Biochemical and neurochemical estimations were carried out to explore the possible mechanism of action. GC-MS analysis of EO showed the presence of a number of biologically active compounds. EO at the dose of 500, 1000 and 2000 mg/kg, p.o. on acute and chronic administration, decreased locomotor activity, immobility duration and latency to climb the pole. EO was effective to facilitate the release of GABA, increase GSH levels, inhibit dopamine neurotransmission and decrease TNF-α levels as well as diminish AChE activity in different regions of the brain. EO at the dose of 500, 1000 mg/kg did not produce cataleptic behavior in rats. EO at the dose of 500, 1000 mg/kg produced protective effects against ketamine-induced psychosis and can be further explored clinically against neuropsychiatric disorders.

Does anesthetic additivity imply a similar molecular mechanism of anesthetic action at N-methyl-D-aspartate receptors?

PubMed

Brosnan, Robert J; Pham, Trung L

2011-03-01

Isoflurane and carbon dioxide (CO(2)) negatively modulate N-methyl-d-aspartate (NMDA) receptors, but via different mechanisms. Isoflurane is a competitive antagonist at the NMDA receptor glycine binding site, whereas CO(2) inhibits NMDA receptor current through extracellular acidification. Isoflurane and CO(2) exhibit additive minimum alveolar concentration effects in rats, but we hypothesized that they would not additively inhibit NMDA receptor currents in vitro because they act at different molecular sites. NMDA receptors were expressed in frog oocytes and studied using 2-electrode voltage clamp techniques. A glycine concentration response for NMDA was measured in the presence and absence of CO(2). Concentration-response curves for isoflurane, H(+), CO(2), and ketamine as a function of NMDA inhibition were measured, and a Hill equation was used to calculate the EC(50) for each compound. Binary drug combinations containing ½ EC(50) were additive if NMDA current inhibition was not statistically different from 50%. The ½ EC(50) binary drug combinations decreased the percentage baseline NMDA receptor current as follows (mean ± SD, n = 5 to 6 oocytes each): CO(2)+ H(+) (51% ± 5%), CO(2 )+ isoflurane (54% ± 5%), H(+) + isoflurane (51% ± 3%), CO(2)+ ketamine (67% ± 8%), and H(+) + ketamine (64% ± 2%). In contrast to our hypothesis, NMDA receptor inhibition by CO(2) and isoflurane is additive. Possibly, CO(2) acidification modulates a pH-sensitive loop on the NMDA receptor that in turn alters glycine binding affinity on the GluN1 subunit. However, ketamine plus either CO(2) or H(+) synergistically inhibits NMDA receptor currents. Drugs acting via different mechanisms can thus exhibit additive or synergistic receptor effects. Additivity may not robustly indicate commonality between molecular anesthetic mechanisms.

Illicit drugs and their metabolites in 36 rivers that drain into the Bohai Sea and north Yellow Sea, north China.

PubMed

Wang, De-Gao; Zheng, Qiu-Da; Wang, Xiao-Ping; Du, Juan; Tian, Chong-Guo; Wang, Zhuang; Ge, Lin-Ke

2016-08-01

Illicit drugs and their metabolites have recently been recognized as an emerging group of contaminants due to their potential ecotoxicological impact in aquatic ecosystems. To date, information on the occurrence of these compounds in the aquatic environment of China remains limited. In this study, we collected surface water samples from 36 rivers in north China that discharge into the Bohai Sea and north Yellow Sea and measured the concentrations of amphetamine-like compounds, ketamines, cocainics, and opioids. The occurrence and spatial patterns of these substances show significant differences between the rivers and regions. Two designer drugs, methamphetamine (METH) and ketamine (KET), were the most abundant compounds detected in the entire set of samples (detection frequency of 92 and 69 %). The concentrations of METH and KET ranged from <0.1 to 42.0 ng L(-1) (mean = 4.53 ng L(-1)) and <0.05 to 4.50 ng L(-1) (mean = 0.49 ng L(-1)), respectively. The high detection frequencies of METH and KET are consistent with the fact that they are the main illicit drugs consumed in China. The high concentrations of these illicit drugs and their metabolites were found in areas that have a high population density. The riverine input of total illicit drugs into the Bohai Sea and north Yellow Sea was estimated to be in the range of 684 to 1160 kg per year.

The effect of target-controlled infusion of low-dose ketamine on heat pain and temporal summation threshold.

PubMed

Lee, Joon-Ho; Cho, Sung-Hwan; Kim, Sang-Hyun; Chae, Won-Soek; Jin, Hee-Cheol; Lee, Jeong-Seok; Kim, Yong-Ik

2011-08-01

We investigated the heat pain threshold (HPT) and temporal summation threshold (TST) before and after target-controlled infusion (TCI) of ketamine with an effect-site concentration (Ce) of 30 and 60 ng/ml. Healthy young volunteers (n = 20) were enrolled. A thermode was applied to the volar side of each volunteer's right forearm, and HPT and TST were measured before and after TCI of ketamine. Vital signs and psychedelic effects according to ketamine infusion were also observed before and after TCI of ketamine. Mean HPT after TCI of ketamine with a Ce of 30 and 60 ng/ml did not increase significantly. However, mean TST after TCI of ketamine with a Ce of 30 and 60 ng/ml increased significantly, in a dose-dependent fashion, compared with the value before ketamine TCI. Vital signs showed no significant difference before and after ketamine TCI. The visual analog scale score of psychedelic symptoms was higher with a Ce of 60 ng/ml than with 30 ng/ml. TCI of ketamine with a Ce of 30 and 60 ng/ml increased TST but not HPT.

Ketamine for Analgosedation in the Intensive Care Unit: A Systematic Review.

PubMed

Patanwala, Asad E; Martin, Jennifer R; Erstad, Brian L

2017-07-01

To evaluate the evidence for the use of intravenous ketamine for analgosedation in the intensive care unit. MEDLINE and EMBASE were queried from inception until July 2015. Search terms used included ketamine, intensive care, and critical care. The search retrieved 584 articles to be screened for inclusion. The intent was to include randomized controlled studies using sustained intravenous infusions (>24 hours) of ketamine in the critically ill patients. One trial evaluated opioid consumption as an outcome in postoperative critically ill patients who were randomized to ketamine or saline infusions. The mean cumulative morphine consumption at 48 hours was significantly lower in the ketamine group (58 ± 35 mg) compared to the morphine-only group (80 ± 37 mg; P < .05). Other trials showed the potential safety of ketamine in terms of cerebral hemodynamics in patients with traumatic brain injury, improved gastrointestinal motility, and decreased vasopressor requirements. The observational study and case reports suggest that ketamine is safe and effective and may have a role in patients who are refractory to other therapies. Ketamine use may decrease analgesic consumption in the intensive care unit. Additional trials are needed to further delineate the role of ketamine for analgosedation.

Ketamine-induced ventricular structural, sympathetic and electrophysiological remodelling: pathological consequences and protective effects of metoprolol

PubMed Central

Li, Y; Shi, J; Yang, BF; Liu, L; Han, CL; Li, WM; Dong, DL; Pan, ZW; Liu, GZ; Geng, JQ; Sheng, L; Tan, XY; Sun, DH; Gong, ZH; Gong, YT

2012-01-01

BACKGROUND AND PURPOSE Growing evidence suggests that long-term abuse of ketamine does harm the heart and increases the risk of sudden death. The present study was performed to explore the cardiotoxicity of ketamine and the protective effects of metoprolol. EXPERIMENTAL APPROACH Rats and rabbits were divided into control, ketamine, metoprolol alone and ketamine plus metoprolol groups. Ketamine (40 mg·kg−1·day−1, i.p.) and metoprolol (20 mg·kg−1·day−1, p.o.) were administered continuously for 12 weeks in rats and 8 weeks in rabbits. Cardiac function, electrophysiological disturbances, cardiac collagen, cardiomyocte apoptosis and the remodelling-related proteins were evaluated. KEY RESULTS Rabbits treated with ketamine showed decreased left ventricular ejection fraction, slowed ventricular conduction velocity and increased susceptibility to ventricular arrhythmia. Metoprolol prevented these pathophysiological alterations. In ketamine-treated rats, cardiac collagen volume fraction and apoptotic cell number were higher than those of control animals; these effects were prevented by co-administration of metoprolol. Consistently, the expressions of poly (ADP-ribose) polymerases-1, apoptosis-inducing factor and NF-κB-light-chain-enhancer of activated B cells were all increased after ketamine treatment and sharply reduced after metoprolol administration. Moreover, ketamine enhanced sympathetic sprouting, manifested as increased growth-associated protein 43 and tyrosine TH expression. These effects of ketamine were prevented by metoprolol. CONCLUSIONS AND IMPLICATIONS Chronic treatment with ketamine caused significant ventricular myocardial apoptosis, fibrosis and sympathetic sprouting, which altered the electrophysiological properties of the heart and increased its susceptibility to malignant arrhythmia that may lead to sudden cardiac death. Metoprolol prevented the cardiotoxicity of ketamine, indicating a promising new therapeutic strategy. PMID:21883145

Current Ketamine Practice: Results of the 2016 American Society of Pain Management Nursing Survey on Ketamine.

PubMed

Klaess, Cynthia C; Jungquist, Carla R

2018-06-01

Ketamine is increasingly utilized for a variety of pain management challenges. Audience comments from a ketamine presentation at the 2015 American Society of Pain Management Nursing (ASPMN) Conference reflected wide variation in ketamine practices as well as barriers to use. The goal was to gain a greater understanding of ASPMN member practice patterns and barriers related to ketamine as adjunctive therapy for pain management. A questionnaire survey design was used. Respondents represented 35 states and 2 countries. The participants were 146 respondents from ASPMN membership (1,485 members). The survey was distributed by ASPMN on SurveyMonkey. Practice setting and ketamine administration practices were assessed with areas for comments. Results were reviewed using frequencies to describe responses and formatted into tables. Comments were individually reviewed and grouped into common themes. Administration of ketamine as an analgesic was reported by 63% of respondents. Continuous intravenous ketamine infusions were the most common route of administration (65%); however, wide variability in dosing and length of therapy was reported. A wide variety of practices and challenges related to ketamine utilization were noted. Numerous studies have indicated the analgesic benefits of ketamine in pain management. The lack of practice standardization has created challenges to its consistent use and outcome measurement. Additionally, the off-label use of ketamine for pain management creates its own unique challenges. However, given the current national climate with intense focus on pain management, interdisciplinary practitioners have an ideal opportunity to evaluate ketamine's use in a comprehensive approach to pain management. Copyright © 2018 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Ketamine and the metabolite norketamine: persistence and phototransformation toxicity in hospital wastewater and surface water.

PubMed

Lin, Angela Yu-Chen; Lee, Wan-Ning; Wang, Xiao-Huan

2014-04-15

Ketamine has been increasingly used both recreationally and medicinally around the world. Although the metabolic pathways to form its metabolite norketamine have been carefully investigated in humans and animals, knowledge of their environmental occurrence and fate is limited. In this study, we investigated the occurrence of ketamine and norketamine in 20 natural bodies of water, effluents from 13 hospitals, two wastewater treatment plants and one water supply plant. Ketamine was found at concentrations as high as 10 μg/L. Ketamine and norketamine were consistently found in similar concentrations (ketamine/norketamine ratio: 0.3-4.6) in the collected water samples, and this ratio similar to that found in urine samples. Dark incubation experiments have shown that ketamine is not susceptible to microbial degradation or hydrolysis. Phototransformation was demonstrated to significantly reduce the concentration of ketamine and norketamine in river waters (t(1/2) = 12.6 ± 0.4 and 10.1 ± 0.4 h, respectively) and resulted in byproducts that are similar to human metabolites. Both direct and indirect photolysis led to the N-demethylation of ketamine to form norketamine and other byproducts, including hydroxy-norketamine (HNK), dehydronorketamine (DNK), hydroxy-ketamine (HK) and isomer forms of ketamine and norketamine. Irradiated solutions exhibited higher toxicity (via the Microtox test). Although a final risk assessment could not be made due to a lack of studies on the chronic effects on aquatic organisms, the high and persistent environmental occurrences of ketamine and norketamine as well as the increasingly acute toxicity of the photo byproducts demonstrate the importance of including metabolites in evaluation of the overall risk of ketamine. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of Ketamine and Ketamine Metabolites on Evoked Striatal Dopamine Release, Dopamine Receptors, and Monoamine Transporters

PubMed Central

Can, Adem; Zanos, Panos; Moaddel, Ruin; Kang, Hye Jin; Dossou, Katinia S. S.; Wainer, Irving W.; Cheer, Joseph F.; Frost, Douglas O.; Huang, Xi-Ping

2016-01-01

Following administration at subanesthetic doses, (R,S)-ketamine (ketamine) induces rapid and robust relief from symptoms of depression in treatment-refractory depressed patients. Previous studies suggest that ketamine’s antidepressant properties involve enhancement of dopamine (DA) neurotransmission. Ketamine is rapidly metabolized to (2S,6S)- and (2R,6R)-hydroxynorketamine (HNK), which have antidepressant actions independent of N-methyl-d-aspartate glutamate receptor inhibition. These antidepressant actions of (2S,6S;2R,6R)-HNK, or other metabolites, as well as ketamine’s side effects, including abuse potential, may be related to direct effects on components of the dopaminergic (DAergic) system. Here, brain and blood distribution/clearance and pharmacodynamic analyses at DA receptors (D1–D5) and the DA, norepinephrine, and serotonin transporters were assessed for ketamine and its major metabolites (norketamine, dehydronorketamine, and HNKs). Additionally, we measured electrically evoked mesolimbic DA release and decay using fast-scan cyclic voltammetry following acute administration of subanesthetic doses of ketamine (2, 10, and 50 mg/kg, i.p.). Following ketamine injection, ketamine, norketamine, and multiple hydroxynorketamines were detected in the plasma and brain of mice. Dehydronorketamine was detectable in plasma, but concentrations were below detectable limits in the brain. Ketamine did not alter the magnitude or kinetics of evoked DA release in the nucleus accumbens in anesthetized mice. Neither ketamine’s enantiomers nor its metabolites had affinity for DA receptors or the DA, noradrenaline, and serotonin transporters (up to 10 μM). These results suggest that neither the side effects nor antidepressant actions of ketamine or ketamine metabolites are associated with direct effects on mesolimbic DAergic neurotransmission. Previously observed in vivo changes in DAergic neurotransmission following ketamine administration are likely indirect. PMID:27469513

Clinically Relevant Concentrations of Ketamine Inhibit Osteoclast Formation In Vitro in Mouse Bone Marrow Cultures.

PubMed

Du, Erxia; McAllister, Patrick; Venna, Venugopal Reddy; Xiao, Liping

2017-04-01

Ketamine has been used safely in clinics for decades for analgesia and anesthesia. It is increasingly popular in clinical practice due to its new uses and importance for emergency procedures. It is known that ketamine is sequestered in the bone marrow and the major receptors for ketamine, noncompetitive N-methyl-d-aspartate receptors (NMDARs), are expressed in osteoclasts (OCs) and osteoblasts. However, the impact of ketamine on OCs or osteoblasts is unknown. In this study, we investigated the effects of ketamine on osteoclastogenesis and regulation of NMDARs expression in vitro. Bone marrows (BMs) or bone marrow macrophages (BMMs) were cultured in the presence of macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor kappa-B ligand (RANKL) with or without ketamine for up to 6 days. OC formation peaked at day 5. On day 5 of culture, ketamine inhibited OC formation from both BM and BMM cultures at clinically relevant concentrations (3-200 µM). Ketamine inhibited RANKL-induced expression of nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1) in BMM cultures. Inhibition of ketamine on RANKL-induced osteoclastogenesis is associated with down-regulation of NMDARs. In addition, ketamine significantly inhibited the M-CSF induced migration of BMMs, inhibited cell fusion and significantly increased mature OC apoptosis. We conclude that clinically relevant concentrations of ketamine inhibit OC formation in both BM and BMM cultures in vitro through inhibiting migration and fusion process and enhancing mature OC apoptosis. It is likely that ketamine regulates osteoclastogenesis, at least in part, via its effects on NMDAR expression. J. Cell. Biochem. 118: 914-923, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Analysis of print news media framing of ketamine treatment in the United States and Canada from 2000 to 2015

PubMed Central

2017-01-01

Objectives There are multifaceted views on the use of ketamine, a potentially addictive substance, to treat mental health problems. The past 15 years have seen growing media coverage of ketamine for medical and other purposes. This study examined the print news media coverage of medical and other uses of ketamine in North America to determine orientations and trends over time. Methods Print newspaper coverage of ketamine from 2000 to 2015 was reviewed, resulting in 43 print news articles from 28 North American newspapers. A 55-item structured coding instrument was applied to assess news reports of ketamine. Items captured negative and positive aspects, therapeutic use of ketamine, and adverse side effects. Chi-squares tested for changes in trends over time. Results In the 15-year reviewed period, the three most frequent themes related to ketamine were: abuse (68.2%), legal status (34.1%), and clinical use in anesthesia (31.8%). There was significant change in trends during two periods (2000–2007 and 2008–2015). In 2008–2015, print news media articles were significantly more likely to encourage clinical use of ketamine to treat depression (p = 0.002), to treat treatment resistant depression (p = 0.043), and to claim that ketamine is more effective than conventional antidepressants (p = 0.043). Conclusions Our review found consistent positive changes in the portrayals of ketamine by the print news media as a therapeutic antidepressant that mirror the recent scientific publications. These changes in news media reporting might influence the popularity of ketamine use to treat clinical depression. Guidance is required for journalists on objective reporting of medical research findings, including limitations of current research evidence and potential risks of ketamine. PMID:28257514

Increased risk of developing schizophrenia in animals exposed to cigarette smoke during the gestational period.

PubMed

Zugno, Alexandra I; Oliveira, Mariana B; Mastella, Gustavo A; Heylmann, Alexandra S A; Canever, Lara; Pacheco, Felipe D; Damazio, Louyse S; Citadin, Sullivan A; de Lucca, Luiz Antonio; Simões, Lutiana Roque; Malgarin, Fernanda; Budni, Josiane; Barichello, Tatiana; Schuck, Patricia F; Quevedo, João

2017-04-03

Cigarette smoking during the prenatal period has been investigated as a causative factor of obstetric abnormalities, which lead to cognitive and behavioural changes associated with schizophrenia. The aim of this study was to investigate behaviour and AChE activity in brain structures in adult rats exposed to cigarette smoke during the prenatal period. Pregnant rats were divided into non-PCSE (non-prenatal cigarette smoke exposure) and PCSE (prenatal cigarette smoke exposure) groups. On post-natal day 60, the rats received saline or ketamine for 7days and were subjected to behavioural tasks. In the locomotor activity task, the non-PCSE+ketamine and PCSE+ketamine groups exhibited increased locomotor activity compared with the saline group. In the social interaction task, the non-PCSE+ketamine and PCSE+ketamine groups exhibited an increased latency compared with the control groups. However, the PCSE+ketamine group exhibited a decreased latency compared with the non-PCSE+ketamine group, which indicates that the cigarette exposure appeared to decrease, the social deficits generated by ketamine. In the inhibitory avoidance task, the non-PCSE+ketamine, PCSE, and PCSE+ketamine groups exhibited impairments in working memory, short-term memory, and long-term memory. In the pre-pulse inhibition (PPI) test, cigarette smoke associated with ketamine resulted in impaired PPI in 3 pre-pulse (PP) intensity groups compared with the control groups. In the biochemical analysis, the AChE activity in brain structures increased in the ketamine groups; however, the PCSE+ketamine group exhibited an exacerbated effect in all brain structures. The present study indicates that exposure to cigarette smoke during the prenatal period may affect behaviour and cerebral cholinergic structures during adulthood. Copyright © 2017 Elsevier Inc. All rights reserved.

Analysis of print news media framing of ketamine treatment in the United States and Canada from 2000 to 2015.

PubMed

Zhang, Melvyn W B; Hong, Ying X; Husain, Syeda F; Harris, Keith M; Ho, Roger C M

2017-01-01

There are multifaceted views on the use of ketamine, a potentially addictive substance, to treat mental health problems. The past 15 years have seen growing media coverage of ketamine for medical and other purposes. This study examined the print news media coverage of medical and other uses of ketamine in North America to determine orientations and trends over time. Print newspaper coverage of ketamine from 2000 to 2015 was reviewed, resulting in 43 print news articles from 28 North American newspapers. A 55-item structured coding instrument was applied to assess news reports of ketamine. Items captured negative and positive aspects, therapeutic use of ketamine, and adverse side effects. Chi-squares tested for changes in trends over time. In the 15-year reviewed period, the three most frequent themes related to ketamine were: abuse (68.2%), legal status (34.1%), and clinical use in anesthesia (31.8%). There was significant change in trends during two periods (2000-2007 and 2008-2015). In 2008-2015, print news media articles were significantly more likely to encourage clinical use of ketamine to treat depression (p = 0.002), to treat treatment resistant depression (p = 0.043), and to claim that ketamine is more effective than conventional antidepressants (p = 0.043). Our review found consistent positive changes in the portrayals of ketamine by the print news media as a therapeutic antidepressant that mirror the recent scientific publications. These changes in news media reporting might influence the popularity of ketamine use to treat clinical depression. Guidance is required for journalists on objective reporting of medical research findings, including limitations of current research evidence and potential risks of ketamine.

Repeated intranasal ketamine for treatment-resistant depression - the way to go? Results from a pilot randomised controlled trial.

PubMed

Gálvez, Verònica; Li, Adrienne; Huggins, Christina; Glue, Paul; Martin, Donel; Somogyi, Andrew A; Alonzo, Angelo; Rodgers, Anthony; Mitchell, Philip B; Loo, Colleen K

2018-04-01

Ketamine research in depression has mostly used intravenous, weight-based approaches, which are difficult to translate clinically. Intranasal (IN) ketamine is a promising alternative but no controlled data has been published on the feasibility, safety and potential efficacy of repeated IN ketamine treatments. This randomised, double-blind, placebo-controlled pilot study compared a 4-week course of eight treatments of 100 mg ketamine or 4.5 mg midazolam. Each treatment was given as 10 separate IN sprays, self-administered 5 min apart. The study was stopped early due to poor tolerability after five treatment-resistant depressed participants were included. Feasibility, safety (acute and cumulative), cognitive and efficacy outcomes were assessed. Plasma ketamine and norketamine concentrations were assayed after the first treatment. Significant acute cardiovascular, psychotomimetic and neurological side effects occurred at doses < 100 mg ketamine. No participants were able to self-administer all 10 ketamine sprays due to incoordination; treatment time occasionally had to be extended (>45 min) due to acute side effects. No hepatic, cognitive or urinary changes were observed after the treatment course in either group. There was an approximately two-fold variation in ketamine and norketamine plasma concentrations between ketamine participants. At course end, one participant had remitted in each of the ketamine and midazolam groups. IN ketamine, with the drug formulation and delivery device used, was not a useful treatment approach in this study. Absorption was variable between individuals and acute tolerability was poor, requiring prolonged treatment administration time in some individuals. The drug formulation, the delivery device, the insufflation technique and individual patient factors play an important role in tolerability and efficacy when using IN ketamine for TRD.

Persistent antidepressant effect of low-dose ketamine and activation in the supplementary motor area and anterior cingulate cortex in treatment-resistant depression: A randomized control study.

PubMed

Chen, Mu-Hong; Li, Cheng-Ta; Lin, Wei-Chen; Hong, Chen-Jee; Tu, Pei-Chi; Bai, Ya-Mei; Cheng, Chih-Ming; Su, Tung-Ping

2018-01-01

A single low-dose ketamine infusion exhibited a rapid antidepressant effect within 1h. Despite its short biological half-life (approximately 3h), the antidepressant effect of ketamine has been demonstrated to persist for several days. However, changes in brain function responsible for the persistent antidepressant effect of a single low-dose ketamine infusion remain unclear METHODS: Twenty-four patients with treatment-resistant depression (TRD) were randomized into three groups according to the treatment received: 0.5mg/kg ketamine, 0.2mg/kg ketamine, and normal saline infusion. Standardized uptake values (SUVs) of glucose metabolism measured through 18 F-FDG positron-emission-tomography before infusion and 1day after a 40-min ketamine or normal saline infusion were used for subsequent whole-brain voxel-wise analysis and were correlated with depressive symptoms, as defined using the Hamilton Depression Rating Scale-17 (HDRS-17) score RESULTS: The voxel-wise analysis revealed that patients with TRD receiving the 0.5mg/kg ketamine infusion had significantly higher SUVs (corrected for family-wise errors, P = 0.014) in the supplementary motor area (SMA) and dorsal anterior cingulate cortex (dACC) than did those receiving the 0.2mg/kg ketamine infusion. The increase in the SUV in the dACC was negatively correlated with depressive symptoms at 1day after ketamine infusion DISCUSSION: The persistent antidepressant effect of a 0.5mg/kg ketamine infusion may be mediated by increased activation in the SMA and dACC. The higher increase in dACC activation was related to the reduction in depressive symptoms after ketamine infusion. A 0.5mg/kg ketamine infusion facilitated the glutamatergic neurotransmission in the SMA and dACC, which may be responsible for the persistent antidepressant effect of ketamine much beyond its half-life. Copyright © 2017 Elsevier B.V. All rights reserved.

Pharmacokinetics of S-ketamine during prolonged sedation at the pediatric intensive care unit.

PubMed

Flint, Robert B; Brouwer, Carole N M; Kränzlin, Anne S C; Lie-A-Huen, Loraine; Bos, Albert P; Mathôt, Ron A A

2017-11-01

S-ketamine is the S(+)-enantiomer of the racemic mixture ketamine, an anesthetic drug providing both sedation and analgesia. In clinical practice, significant interpatient variability in drug effect of S-ketamine is observed during long-term sedation. The aim of this study was to evaluate the pharmacokinetic variability of S-ketamine in children aged 0-18 years during long-term sedation. Twenty-five children (median age: 0.42 years, range: 0.02-12.5) received continuous intravenous administrations of 0.3-3.6 mg/kg/h S-ketamine for sedation during mechanical ventilation. Infusion rates were adjusted to the desired level of sedation and analgesia based on the COMFORT-B score and Visual Analog Scale. Blood samples were drawn once daily at random time-points, and at 1 and 4 hours after discontinuation of S-ketamine infusion. Time profiles of plasma concentrations of S-ketamine and active metabolite S-norketamine were analyzed using nonlinear mixed-effects modeling software. Clearance and volume of distribution were allometrically scaled using the ¾ power model. A total of 86 blood samples were collected. A 2-compartment and 1-compartment model adequately described the PK of S-ketamine and S-norketamine, respectively. The typical parameter estimates for clearance and central and peripheral volumes of distribution were: CL S - KETAMINE =112 L/h/70 kg, V1 S- KETAMINE =7.7 L/70 kg, V2 S- KETAMINE =545L/70 kg, Q S - kETAMINE =196 L/h/70 kg, and CL S - NORKETAMINE =53 L/h/70 kg. Interpatient variability of CL S - KETAMINE and CL S - NORKETAMINE was considerable with values of 40% and 104%, respectively, leading to marked variability in steady-state plasma concentrations. Substantial interpatient variability in pharmacokinetics in children complicates the development of adequate dosage regimen for continuous sedation. © 2017 John Wiley & Sons Ltd.

A PK-PD model of ketamine-induced high-frequency oscillations

NASA Astrophysics Data System (ADS)

Flores, Francisco J.; Ching, ShiNung; Hartnack, Katharine; Fath, Amanda B.; Purdon, Patrick L.; Wilson, Matthew A.; Brown, Emery N.

2015-10-01

Objective. Ketamine is a widely used drug with clinical and research applications, and also known to be used as a recreational drug. Ketamine produces conspicuous changes in the electrocorticographic (ECoG) signals observed both in humans and rodents. In rodents, the intracranial ECoG displays a high-frequency oscillation (HFO) which power is modulated nonlinearly by ketamine dose. Despite the widespread use of ketamine there is no model description of the relationship between the pharmacokinetic-pharmacodynamics (PK-PDs) of ketamine and the observed HFO power. Approach. In the present study, we developed a PK-PD model based on estimated ketamine concentration, its known pharmacological actions, and observed ECoG effects. The main pharmacological action of ketamine is antagonism of the NMDA receptor (NMDAR), which in rodents is accompanied by an HFO observed in the ECoG. At high doses, however, ketamine also acts at non-NMDAR sites, produces loss of consciousness, and the transient disappearance of the HFO. We propose a two-compartment PK model that represents the concentration of ketamine, and a PD model based in opposing effects of the NMDAR and non-NMDAR actions on the HFO power. Main results. We recorded ECoG from the cortex of rats after two doses of ketamine, and extracted the HFO power from the ECoG spectrograms. We fit the PK-PD model to the time course of the HFO power, and showed that the model reproduces the dose-dependent profile of the HFO power. The model provides good fits even in the presence of high variability in HFO power across animals. As expected, the model does not provide good fits to the HFO power after dosing the pure NMDAR antagonist MK-801. Significance. Our study provides a simple model to relate the observed electrophysiological effects of ketamine to its actions at the molecular level at different concentrations. This will improve the study of ketamine and rodent models of schizophrenia to better understand the wide and divergent range of effects that ketamine has.

Ketamine Disrupts Frontal and Hippocampal Contribution to Encoding and Retrieval of Episodic Memory: An fMRI Study

PubMed Central

Honey, G.D.; Honey, R.A.E.; O’Loughlin, C.; Sharar, S.R.; Kumaran, D.; Suckling, J.; Menon, D.K.; Sleator, C.; Bullmore, E.T.; Fletcher, P.C.

2012-01-01

The N-methyl-d-aspartate (NMDA) receptor antagonist ketamine produces episodic memory deficits. We used functional magnetic resonance imaging to characterize the effects of ketamine on frontal and hippocampal responses to memory encoding and retrieval in healthy volunteers using a double-blind, placebo-controlled, randomized, within-subjects comparison of two doses of intravenous ketamine. Dissociation of the effects of ketamine on encoding and retrieval processes was achieved using two study-test cycles: in the first, items were encoded prior to drug infusion and retrieval tested, during scanning, on drug; in the second, encoding was scanned on drug, and retrieval tested once ketamine plasma levels had declined. We additionally determined the interaction of ketamine with the depth of processing that occurred at encoding. A number of effects upon task-dependent activations were seen. Overall, our results suggest that left frontal activation is augmented by ketamine when elaborative semantic processing is required at encoding. In addition, successful encoding on ketamine is supplemented by additional non-verbal processing that is incidental to task demands. The effects of ketamine at retrieval are consistent with impaired access to accompanying contextual features of studied items. Our findings show that, even when overt behaviour is unimpaired, ketamine has an impact upon the recruitment of key regions in episodic memory task performance. PMID:15537676

Psychiatric side effects of ketamine in hospitalized medical patients administered subanesthetic doses for pain control.

PubMed

Rasmussen, Keith G

2014-08-01

To assess the psychiatric side effects of ketamine when administered in subanesthetic doses to hospitalized patients. It is hypothesized that such effects occur frequently. In this retrospective study, the medical records of 50 patients hospitalized on medical and surgical units at our facility who had continuous intravenous infusions of ketamine for pain or mild sedation were reviewed. Patient progress in the days following the start of ketamine infusion was reviewed and response to ketamine was noted. Twenty-two percent of the patients were noted to have some type of psychiatric reaction to ketamine, including agitation, confusion, and hallucinations. These reactions were relatively short lived, namely, occurring during or shortly after the infusions. No association was found between patient response to ketamine and gender, age, or infusion rate. Awareness of the psychiatric side effects of ketamine is an important consideration for clinicians administering this medication either for pain control or for depressive illness.

Optogenetic stimulation of infralimbic PFC reproduces ketamine's rapid and sustained antidepressant actions.

PubMed

Fuchikami, Manabu; Thomas, Alexandra; Liu, Rongjian; Wohleb, Eric S; Land, Benjamin B; DiLeone, Ralph J; Aghajanian, George K; Duman, Ronald S

2015-06-30

Ketamine produces rapid and sustained antidepressant actions in depressed patients, but the precise cellular mechanisms underlying these effects have not been identified. Here we determined if modulation of neuronal activity in the infralimbic prefrontal cortex (IL-PFC) underlies the antidepressant and anxiolytic actions of ketamine. We found that neuronal inactivation of the IL-PFC completely blocked the antidepressant and anxiolytic effects of systemic ketamine in rodent models and that ketamine microinfusion into IL-PFC reproduced these behavioral actions of systemic ketamine. We also found that optogenetic stimulation of the IL-PFC produced rapid and long-lasting antidepressant and anxiolytic effects and that these effects are associated with increased number and function of spine synapses of layer V pyramidal neurons. The results demonstrate that ketamine infusions or optogenetic stimulation of IL-PFC are sufficient to produce long-lasting antidepressant behavioral and synaptic responses similar to the effects of systemic ketamine administration.

Sedation of Patients with Acute Aneurysmal Subarachnoid Hemorrhage with Ketamine Is Safe and Might Influence the Occurrence of Cerebral Infarctions Associated with Delayed Cerebral Ischemia.

PubMed

Von der Brelie, Christian; Seifert, Michael; Rot, Sergej; Tittel, Anja; Sanft, Carsten; Meier, Ullrich; Lemcke, Johannes

2017-01-01

Ketamine has neuroprotective characteristics as well as beneficial cardiocirculatory properties and may thus reduce vasopressor consumption. In contrast, sedation with ketamine (like any other sedative drug) has side effects. This study assesses the influence of ketamine on intracranial pressure (ICP), on the consumption of vasopressors in induced hypertension therapy, and on the occurrence of delayed cerebral ischemia (DCI)-associated cerebral infarctions, with particular focus on the complications of sedation in patients with aneurysmal subarachnoid hemorrhage (SAH). This is a retrospective, observational study. Sixty-five patients with SAH who underwent a period of sedation were included. The clinical course variables (Richmond Agitation and Sedation scale score, ICP values, consumption of vasopressors, complications of sedation, outcome, and other clinical parameters) were analyzed. Cranial computed tomography results were analyzed. Forty-one patients underwent sedation including ketamine (63.1%). Ketamine decreased the ICP in 92.7% of the cases. Vasopressors was reduced in 53.6%. DCI-associated cerebral infarctions occurred significantly less often in the patient cohort being treated with sedation including ketamine (7.3% vs. 25% in the nonketamine group; P = 0.04). The rate of major complications was not higher in the ketamine group. Outcome was not different regarding the groups if they were sedated with or without ketamine. Ketamine decreases the ICP and is not associated with a higher rate of complications. The rate of DCI-associated cerebral infarctions was lower in the ketamine group. Ketamine administration led to a reduction of vasopressors used for induced hypertension. Copyright © 2016 Elsevier Inc. All rights reserved.

Ketamine changes the local resting-state functional properties of anesthetized-monkey brain.

PubMed

Rao, Jia-Sheng; Liu, Zuxiang; Zhao, Can; Wei, Rui-Han; Zhao, Wen; Tian, Peng-Yu; Zhou, Xia; Yang, Zhao-Yang; Li, Xiao-Guang

2017-11-01

Ketamine is a well-known anesthetic. 'Recreational' use of ketamine common induces psychosis-like symptoms and cognitive impairments. The acute and chronic effects of ketamine on relevant brain circuits have been studied, but the effects of single-dose ketamine administration on the local resting-state functional properties of the brain remain unknown. In this study, we aimed to assess the effects of single-dose ketamine administration on the brain local intrinsic properties. We used resting-state functional magnetic resonance imaging (rs-fMRI) to explore the ketamine-induced alterations of brain intrinsic properties. Seven adult rhesus monkeys were imaged with rs-fMRI to examine the fractional amplitude of low-frequency fluctuation (fALFF) and regional homogeneity (ReHo) in the brain before and after ketamine injection. Paired comparisons were used to detect the significantly altered regions. Results showed that the fALFF of the prefrontal cortex (p=0.046), caudate nucleus (left side, p=0.018; right side, p=0.025), and putamen (p=0.020) in post-injection stage significantly increased compared with those in pre-injection period. The ReHo of nucleus accumbens (p=0.049), caudate nucleus (p=0.037), and hippocampus (p=0.025) increased after ketamine injection, but that of prefrontal cortex decreased (p<0.05). These findings demonstrated that single-dose ketamine administration can change the regional intensity and synchronism of brain activity, thereby providing evidence of ketamine-induced abnormal resting-state functional properties in primates. This evidence may help further elucidate the effects of ketamine on the cerebral resting status. Copyright © 2017. Published by Elsevier Inc.

Management of Neuropathic Chronic Pain with Methadone Combined with Ketamine: A Randomized, Double Blind, Active-Controlled Clinical Trial.

PubMed

Rigo, Flavia Karine; Trevisan, Gabriela; Godoy, Maria C; Rossato, Mateus Fortes; Dalmolin, Gerusa D; Silva, Mariane A; Menezes, Mirian S; Caumo, Wolnei; Ferreira, Juliano

2017-03-01

Methadone and ketamine are used in neuropathic pain management. However, the benefits of both drugs association are uncertain in the treatment of neuropathic pain. Our primary objective was test the hypothesis that oral methadone combined with oral ketamine is more effective than oral methadone or ketamine alone in reducing neuropathic pain. We conducted a randomized, double blind, active-controlled parallel-group clinical trial. Forty-two patients with neuropathic pain refractory to conventional therapy were randomly assigned to receive oral methadone (n = 14), ketamine (n = 14), or methadone plus ketamine (n = 14) over a 3-month period. During these 90 days, we observed pain scores using a visual analogical scale (VAS), allodynia, burning/shooting pain, and some side effects. All treatments were effective in reducing pain scores by at least 40%. However, a significant improvement in pain was observed only in the ketamine alone group compared with both the methadone or methadone/ketamine groups. No significant differences were observed among the treatment groups for the reduction of burning or shooting pain, while ketamine alone was more effective than methadone or methadone/ketamine for the reduction of allodynia. Formal assessment for awareness of the allocation was not performed, some co-intervention bias may have occurred, our results could be only relevant to the patient population investigated and the use of VAS as the primary outcome detect changes in pain intensity but not to assess neuropathic pain symptoms. This study indicates that ketamine was better than methadone or methadone/ketamine for treating neuropathic pain.Key words: Multimodal analgesia, refractory pain, NMDA receptor, opioid.

Sedation or Inhalant Anesthesia before Euthanasia with CO2 Does Not Reduce Behavioral or Physiologic Signs of Pain and Stress in Mice

PubMed Central

Valentine, Helen; Williams, Wendy O; Maurer, Kirk J

2012-01-01

CO2 administration is a common euthanasia method for research mice, yet questions remain regarding whether CO2 euthanasia is associated with pain and stress. Here we assessed whether premedication with acepromazine, midazolam, or anesthetic induction with isoflurane altered behavioral and physiologic parameters that may reflect pain or stress during CO2 euthanasia. Mice were assigned to 1 of 6 euthanasia groups: CO2 only at a flow rate of 1.2 L/min which displaces 20% of the cage volume per minute (V/min; control group); premedication with acepromazine (5 mg/kg), midazolam (5 mg/kg), or saline followed by 20% V/min CO2; induction with 5% isoflurane followed by greater than 100% V/min CO2 (>6L/min); and 100% V/min CO2 only (6 L/min). Measures included ultrasonic sound recordings, behavioral analysis of video recordings, plasma ACTH and corticosterone levels immediately after euthanasia, and quantification of c-fos from brain tissue. Compared with 20% V/min CO2 alone, premedication with acepromazine or midazolam did not significantly alter behavior but did induce significantly higher c-fos expression in the brain. Furthermore, the use of isoflurane induction prior to CO2 euthanasia significantly increased both behavioral and neuromolecular signs of stress. The data indicate that compared with other modalities, 20% V/min CO2 alone resulted in the least evidence of stress in mice and therefore was the most humane euthanasia method identified in the current study. PMID:22330868

Sedation or inhalant anesthesia before euthanasia with CO2 does not reduce behavioral or physiologic signs of pain and stress in mice.

PubMed

Valentine, Helen; Williams, Wendy O; Maurer, Kirk J

2012-01-01

CO(2) administration is a common euthanasia method for research mice, yet questions remain regarding whether CO(2) euthanasia is associated with pain and stress. Here we assessed whether premedication with acepromazine, midazolam, or anesthetic induction with isoflurane altered behavioral and physiologic parameters that may reflect pain or stress during CO(2) euthanasia. Mice were assigned to 1 of 6 euthanasia groups: CO(2) only at a flow rate of 1.2 L/min which displaces 20% of the cage volume per minute (V/min; control group); premedication with acepromazine (5 mg/kg), midazolam (5 mg/kg), or saline followed by 20% V/min CO(2); induction with 5% isoflurane followed by greater than 100% V/min CO(2) (>6L/min); and 100% V/min CO(2) only (6 L/min). Measures included ultrasonic sound recordings, behavioral analysis of video record- ings, plasma ACTH and corticosterone levels immediately after euthanasia, and quantification of c-fos from brain tissue. Compared with 20% V/min CO(2) alone, premedication with acepromazine or midazolam did not significantly alter behavior but did induce significantly higher c-fos expression in the brain. Furthermore, the use of isoflurane induction prior to CO(2) euthanasia significantly increased both behavioral and neuromolecular signs of stress. The data indicate that compared with other modalities, 20% V/min CO(2) alone resulted in the least evidence of stress in mice and therefore was the most humane euthanasia method identified in the current study.

Increasing Ketamine Use for Refractory Status Epilepticus in US Pediatric Hospitals.

PubMed

Keros, Sotirios; Buraniqi, Ersida; Alex, Byron; Antonetty, Annalee; Fialho, Hugo; Hafeez, Baria; Jackson, Michele C; Jawahar, Rachel; Kjelleren, Stephanie; Stewart, Elizabeth; Morgan, Lindsey A; Wainwright, Mark S; Sogawa, Yoshimi; Patel, Anup D; Loddenkemper, Tobias; Grinspan, Zachary M

2017-06-01

Ketamine is an emerging therapy for pediatric refractory status epilepticus. The circumstances of its use, however, are understudied. The authors described pediatric refractory status epilepticus treated with ketamine from 2010 to 2014 at 45 centers using the Pediatric Hospital Inpatient System database. For comparison, they described children treated with pentobarbital. The authors estimated that 48 children received ketamine and pentobarbital for refractory status epilepticus, and 630 pentobarbital without ketamine. Those receiving only pentobarbital were median age 3 [interquartile range 0-10], and spent 30 [18-52] days in-hospital, including 17 [9-28] intensive care unit (ICU) days; 17% died. Median cost was $148 000 [81 000-241 000]. The pentobarbital-ketamine group was older (7 [2-11]) with longer hospital stays (51 [30-93]) and more ICU days (29 [20-56]); 29% died. Median cost was $298 000 [176 000-607 000]. For 71%, ketamine was given ≥1 day after pentobarbital. Ketamine cases per half-year increased from 2 to 9 ( P < .05). Ketamine is increasingly used for severe pediatric refractory status epilepticus, typically after pentobarbital. Research on its effectiveness is indicated.

Environmental enrichment and abstinence attenuate ketamine-induced cardiac and renal toxicity

PubMed Central

Li, Xingxing; Li, Shuangyan; Zheng, Wenhui; Pan, Jian; Huang, Kunyu; Chen, Rong; Pan, Tonghe; Liao, Guorong; Chen, Zhongming; Zhou, Dongsheng; Shen, Wenwen; Zhou, Wenhua; Liu, Yu

2015-01-01

The current study was designed to investigate the effect of abstinence in combination with environmental enrichment (EE) on cardiac and renal toxicity induced by 2 weeks of ketamine self-administration (SA) in rodents. In Experiment 1, one group of rats underwent ketamine SA for 14 days. In Experiment 2, the animals completed 2 weeks of ketamine SA followed by 2 and 4 weeks of abstinence. In Experiment 3, animals underwent 14 days of ketamine SA and 4 weeks of abstinence in which isolated environment (IE) and EE was introduced. The corresponding control groups were included for each experiment. Two weeks of ketamine SA caused significant increases in organ weight, Apoptosis Stimulating Fragment/Kidney Injury Molecule-1, and apoptotic level of heart and kidney. The extended length of withdrawal from ketamine SA partially reduced toxicity on the heart and kidney. Finally, introduction of EE during the period of abstinence greatly promoted the effect of abstinence on ketamine-induced cardiac and renal toxicity. The interactive effect of EE and abstinence was promising to promote the recovery of cardiac and renal toxicity of ketamine. PMID:26112338

Ketamine produces antidepressant-like effects through phosphorylation-dependent nuclear export of histone deacetylase 5 (HDAC5) in rats

PubMed Central

Choi, Miyeon; Lee, Seung Hoon; Wang, Sung Eun; Ko, Seung Yeon; Song, Mihee; Choi, June-Seek; Duman, Ronald S.; Son, Hyeon

2015-01-01

Ketamine produces rapid antidepressant-like effects in animal assays for depression, although the molecular mechanisms underlying these behavioral actions remain incomplete. Here, we demonstrate that ketamine rapidly stimulates histone deacetylase 5 (HDAC5) phosphorylation and nuclear export in rat hippocampal neurons through calcium/calmodulin kinase II- and protein kinase D-dependent pathways. Consequently, ketamine enhanced the transcriptional activity of myocyte enhancer factor 2 (MEF2), which leads to regulation of MEF2 target genes. Transfection of a HDAC5 phosphorylation-defective mutant (Ser259/Ser498 replaced by Ala259/Ala498, HDAC5-S/A), resulted in resistance to ketamine-induced nuclear export, suppression of ketamine-mediated MEF2 transcriptional activity, and decreased expression of MEF2 target genes. Behaviorally, viral-mediated hippocampal knockdown of HDAC5 blocked or occluded the antidepressant effects of ketamine both in unstressed and stressed animals. Taken together, our results reveal a novel role of HDAC5 in the actions of ketamine and suggest that HDAC5 could be a potential mechanism contributing to the therapeutic actions of ketamine. PMID:26647181

Transient central diabetes insipidus induced by ketamine infusion.

PubMed

Hatab, Sarah Z; Singh, Arun; Felner, Eric I; Kamat, Pradip

2014-12-01

Report a case of central diabetes insipidus (DI) associated with ketamine infusion. A 2-year-old girl with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency and stable hypertrophic cardiomyopathy was admitted to the pediatric intensive care with pneumonia. She subsequently developed respiratory failure and required intubation. Continuous ketamine infusion was used for the sedation and facilitation of mechanical ventilation. Shortly after infusion of ketamine, the patient developed DI and responded appropriately to vasopressin. The Naranjo adverse drug reaction probability scale indicated a probable relationship between the development of central DI and ketamine. The most likely mechanism involves ketamine's antagonist action on N-methyl-d-aspartate receptors, resulting in inhibition of glutamate-stimulated arginine vasopressin release from the neurohypophysis. This is the second case report of ketamine-induced central DI and the only report in children. Clinicians who sedate children with continuous ketamine infusions should monitor patients for developing signs and symptoms of DI by measuring serum sodium and urine output prior to, during, and after ketamine infusion in order to make a timely diagnosis of this potentially serious complication. © The Author(s) 2014.

Ameliorating treatment-refractory depression with intranasal ketamine: potential NMDA receptor actions in the pain circuitry representing mental anguish.

PubMed

Opler, Lewis A; Opler, Mark G A; Arnsten, Amy F T

2016-02-01

This article reviews the antidepressant actions of ketamine, an N-methyl-D-aspartame glutamate receptor (NMDAR) antagonist, and offers a potential neural mechanism for intranasal ketamine's ultra-rapid actions based on the key role of NMDAR in the nonhuman primate prefrontal cortex (PFC). Although intravenous ketamine infusions can lift mood within hours, the current review describes how intranasal ketamine administration can have ultra-rapid antidepressant effects, beginning within minutes (5-40 minutes) and lasting hours, but with repeated treatments needed for sustained antidepressant actions. Research in rodents suggests that increased synaptogenesis in PFC may contribute to the prolonged benefit of ketamine administration, beginning hours after administration. However, these data cannot explain the relief that occurs within minutes of intranasal ketamine delivery. We hypothesize that the ultra-rapid effects of intranasal administration in humans may be due to ketamine blocking the NMDAR circuits that generate the emotional representations of pain (eg, Brodmann Areas 24 and 25, insular cortex), cortical areas that can be overactive in depression and which sit above the nasal epithelium. In contrast, NMDAR blockade in the dorsolateral PFC following systemic administration of ketamine may contribute to cognitive deficits. This novel view may help to explain how intravenous ketamine can treat the symptoms of depression yet worsen the symptoms of schizophrenia.

Longitudinal two-photon imaging in somatosensory cortex of behaving mice reveals dendritic spine formation enhancement by subchronic administration of low-dose ketamine.

PubMed

Pryazhnikov, Evgeny; Mugantseva, Ekaterina; Casarotto, Plinio; Kolikova, Julia; Fred, Senem Merve; Toptunov, Dmytro; Afzalov, Ramil; Hotulainen, Pirta; Voikar, Vootele; Terry-Lorenzo, Ryan; Engel, Sharon; Kirov, Sergei; Castren, Eero; Khiroug, Leonard

2018-04-24

Ketamine, a well-known anesthetic, has recently attracted renewed attention as a fast-acting antidepressant. A single dose of ketamine induces rapid synaptogenesis, which may underlie its antidepressant effect. To test whether repeated exposure to ketamine triggers sustained synaptogenesis, we administered a sub-anesthetic dose of ketamine (10 mg/kg i.p.) once-daily for 5 days, and repeatedly imaged dendritic spines of the YFP-expressing pyramidal neurons in somatosensory cortex of awake female mice using in vivo two-photon microscopy. We found that the spine formation rate became significantly higher at 72-132 h after the first ketamine injection (but not at 6-24 h), while the rate of elimination of pre-existing spines remained unchanged. In contrast to the net gain of spines observed in ketamine-treated mice, the vehicle-injected control mice exhibited a net loss typical for young-adult animals undergoing synapse pruning. Ketamine-induced spinogenesis was correlated with increased PSD-95 and phosphorylated actin, consistent with formation of new synapses. Moreover, structural synaptic plasticity caused by ketamine was paralleled by a significant improvement in the nest building behavioral assay. Taken together, our data show that subchronic low-dose ketamine induces a sustained shift towards spine formation.

Ketamine for pain in adults and children with cancer: a systematic review and synthesis of the literature.

PubMed

Bredlau, Amy Lee; Thakur, Rajbala; Korones, David Nathan; Dworkin, Robert H

2013-10-01

Chronic cancer pain is often refractory and difficult to treat. Ketamine is a medication with evidence of efficacy in the treatment of chronic pain. This article presents a synthesis of the data on ketamine for refractory cancer pain in adults and children. There are five randomized, double-blind, controlled trials of ketamine use in cancer pain that demonstrate improvement in pain for some patients. There are six prospective, uncontrolled trials in cancer pain that also demonstrate improvement in pain scores for some patients. There are no randomized, controlled trials in children with cancer pain, although there are a few studies reflecting improved pain control with ketamine for children with cancer pain. Adverse events for adults on ketamine are most commonly somnolence, feelings of insobriety, nausea/vomiting, hallucinations, depersonalization/derealization, and drowsiness. However, when ketamine is combined with benzodiazepines, feelings of insobriety, hallucinations, and depersonalization/derealization are not reported. Children on ketamine have had few reported adverse effects, which include sedation, anorexia, urinary retention, and myoclonic movements. Recommended ketamine infusion dosages are from 0.05 to 0.5 mg/kg/h (intravenous or subcutaneous). Recommended oral dosages of ketamine are 0.2-0.5 mg/kg/dose two to three times daily with a maximum of 50 mg/dose three times daily. Despite limitations in the breadth and depth of data available, there is evidence that ketamine may be a viable option for treatment-refractory cancer pain. Wiley Periodicals, Inc.

Cognitive and subjective acute dose effects of intramuscular ketamine in healthy adults.

PubMed

Lofwall, Michelle R; Griffiths, Roland R; Mintzer, Miriam Z

2006-11-01

Ketamine is a noncompetitive N-methyl-D-aspartate (NMDA) antagonist. Given the purported role of the NMDA receptor in long-term potentiation, the primary purpose of the present study was to further understand the dose-related effects of ketamine on memory. The study was also designed to provide information about the relative effects of ketamine on memory versus nonmemory effects and to more fully characterize ketamine's overall pattern and time course of effects. Single intramuscular injections of ketamine (0.2 mg/kg, 0.4 mg/kg) were administered to 18 healthy adult volunteers using a double-blind, placebo-controlled, crossover design. Word lists were used to evaluate episodic memory (free recall, recognition memory, source memory) and metamemory. Working memory, time estimation, psychomotor performance, and subjective effects were assessed repeatedly for 5 hours after drug administration. Ketamine selectively impaired encoding (as measured by free recall) while sparing retrieval, working memory while sparing attention, and digit symbol substitution task speed while sparing accuracy. Ketamine did not significantly impair recognition or source memory, metamemory, or time estimation. There were no hallucinations or increases in mystical experiences with ketamine. Memory measures were less sensitive to ketamine effects than subjective or psychomotor measures. Subjective effects lasted longer than memory and most psychomotor impairments. Ketamine produces selective, transient, dose- and time-related effects. In conjunction with previous studies of drugs with different mechanisms of actions, the observed selectivity of effects enhances the understanding of the pharmacological mechanisms underlying memory, attention, psychomotor performance, and subjective experience.

A review of the use of ketamine in pain management.

PubMed

Tawfic, Qutaiba A

2013-01-01

Ketamine is a noncompetitive antagonist of N-methyl-d-aspartate receptor. It has been widely used in anesthesia and pain management. Ketamine has been administered via the intravenous, intramuscular, subcutaneous, oral, rectal, topical, intranasal, sublingual, epidural, and caudal routes. Ketamine improves postoperative and posttrauma pain scores and reduces opioid consumption. It has special indication for patients with opioid tolerance, acute hyperalgesia, and neuropathic pain. It also has a role in the management of chronic pain including both cancer and noncancer pain. Recreational use of ketamine is increasing as well through different routes of administration like inhalation, smoking, or intravenous injection. Long-time exposure to ketamine, especially in the abusers, may lead to serious side effects. This review is trying to define the role of ketamine in pain management.

Effects of ketamine on the unconditioned and conditioned locomotor activity of preadolescent and adolescent rats: impact of age, sex, and drug dose.

PubMed

McDougall, Sanders A; Moran, Andrea E; Baum, Timothy J; Apodaca, Matthew G; Real, Vanessa

2017-09-01

Ketamine is used by preadolescent and adolescent humans for licit and illicit purposes. The goal of the present study was to determine the effects of acute and repeated ketamine treatment on the unconditioned behaviors and conditioned locomotor activity of preadolescent and adolescent rats. To assess unconditioned behaviors, female and male rats were injected with ketamine (5-40 mg/kg), and distance traveled was measured on postnatal day (PD) 21-25 or PD 41-45. To assess conditioned activity, male and female rats were injected with saline or ketamine in either a novel test chamber or the home cage on PD 21-24 or PD 41-44. One day later, rats were injected with saline and conditioned activity was assessed. Ketamine produced a dose-dependent increase in the locomotor activity of preadolescent and adolescent rats. Preadolescent rats did not exhibit sex differences, but ketamine-induced locomotor activity was substantially stronger in adolescent females than males. Repeated ketamine treatment neither caused a day-dependent increase in locomotor activity nor produced conditioned activity in preadolescent or adolescent rats. The activity-enhancing effects of ketamine are consistent with the actions of an indirect dopamine agonist, while the inability of ketamine to induce conditioned activity is unlike what is observed after repeated cocaine or amphetamine treatment. This dichotomy could be due to ketamine's ability to both enhance DA neurotransmission and antagonize N-methyl-D-aspartate (NMDA) receptors. Additional research will be necessary to parse out the relative contributions of DA and NMDA system functioning when assessing the behavioral effects of ketamine during early ontogeny.

Ketamine-induced bladder fibrosis involves epithelial-to-mesenchymal transition mediated by transforming growth factor-β1.

PubMed

Wang, Junpeng; Chen, Yang; Gu, Di; Zhang, Guihao; Chen, Jiawei; Zhao, Jie; Wu, Peng

2017-10-01

Bladder wall fibrosis is a major complication of ketamine-induced cystitis (KC), but the underlying pathogenesis is poorly understood. The aim of the present study was to elucidate the mechanism of ketamine-induced fibrosis in association with epithelial-to-mesenchymal transition (EMT) mediated by transforming growth factor-β1 (TGF-β1). Sprague-Dawley rats were randomly distributed into four groups, which received saline, ketamine, ketamine combined with a TGF-β receptor inhibitor (SB-505124) for 16 wk, or 12 wk of ketamine and 4 wk of abstinence. In addition, the profibrotic effect of ketamine was confirmed in SV-40 immortalized human uroepithelial (SV-HUC-1) cells. The ketamine-treated rats displayed voiding dysfunction and decreased bladder compliance. Bladder fibrosis was accompanied by the appearance of a certain number of cells expressing both epithelial and mesenchymal markers, indicating that epithelial cells might undergo EMT upon ketamine administration. Meanwhile, the expression level of TGF-β1 was significantly upregulated in the urothelium of bladders in ketamine-treated rats. Treatment of SV-HUC-1 cells with ketamine increased the expression of TGF-β1 and EMT-inducing transcription factors, resulting in the downregulation of E-cadherin and upregulation of fibronectin and α-smooth muscle actin. Administration of SB-505124 inhibited EMT and fibrosis both in vitro and vivo. In addition, withdrawal from ketamine did not lead to recovery of bladder urinary function or decreased fibrosis. Taken together, our study shows for the first time that EMT might contribute to bladder fibrosis in KC. TGF-β1 may have an important role in bladder fibrogenesis via an EMT mechanism. Copyright © 2017 the American Physiological Society.

Intravenous S-Ketamine Does Not Inhibit Alveolar Fluid Clearance in a Septic Rat Model

PubMed Central

Weber, Nina C.; van der Sluijs, Koen; Hackl, Florian; Hotz, Lorenz; Dahan, Albert; Hollmann, Markus W.; Berger, Marc M.

2014-01-01

We previously demonstrated that intratracheally administered S-ketamine inhibits alveolar fluid clearance (AFC), whereas an intravenous (IV) bolus injection had no effect. The aim of the present study was to characterize whether continuous IV infusion of S-ketamine, yielding clinically relevant plasma concentrations, inhibits AFC and whether its effect is enhanced in acute lung injury (ALI) which might favor the appearance of IV S-ketamine at the alveolar surface. AFC was measured in fluid-instilled rat lungs. S-ketamine was administered IV over 6 h (loading dose: 20 mg/kg, followed by 20 mg/kg/h), or intratracheally by addition to the instillate (75 µg/ml). ALI was induced by IV lipopolysaccharide (LPS; 7 mg/kg). Interleukin (IL)-6 and cytokine-induced neutrophil chemoattractant (CINC)-3 were measured by ELISA in plasma and bronchoalveolar lavage fluid. Isolated rat alveolar type-II cells were exposed to S-ketamine (75 µg/ml) and/or LPS (1 mg/ml) for 6 h, and transepithelial ion transport was measured as short circuit current (ISC). AFC was 27±5% (mean±SD) over 60 min in control rats and was unaffected by IV S-ketamine. Tracheal S-ketamine reduced AFC to 18±9%. In LPS-treated rats, AFC decreased to 16±6%. This effect was not enhanced by IV S-ketamine. LPS increased IL-6 and CINC-3 in plasma and bronchoalveolar lavage fluid. In alveolar type-II cells, S-ketamine reduced ISC by 37% via a decrease in amiloride-inhibitable sodium transport. Continuous administration of IV S-ketamine does not affect rat AFC even in endotoxin-induced ALI. Tracheal application with direct exposure of alveolar epithelial cells to S-ketamine decreases AFC by inhibition of amiloride-inhibitable sodium transport. PMID:25386677

Locomotor sensitization to intermittent ketamine administration is associated with nucleus accumbens plasticity in male and female rats.

PubMed

Strong, C E; Schoepfer, K J; Dossat, A M; Saland, S K; Wright, K N; Kabbaj, M

2017-07-15

Clinical evidence suggests superior antidepressant response over time with a repeated, intermittent ketamine treatment regimen as compared to a single infusion. However, the club drug ketamine is commonly abused. Therefore, the abuse potential of repeated ketamine injections at low doses needs to be investigated. In this study, we investigated the abuse potential of repeated exposure to either 0, 2.5, or 5 mg/kg ketamine administered once weekly for seven weeks. Locomotor activity and conditioned place preference (CPP) were assayed to evaluate behavioral sensitization to the locomotor activating effects of ketamine and its rewarding properties, respectively. Our results show that while neither males nor females developed CPP, males treated with 5 mg/kg and females treated with either 2.5 or 5 mg/kg ketamine behaviorally sensitized. Furthermore, dendritic spine density was increased in the NAc of both males and females administered 5 mg/kg ketamine, an effect specific to the NAc shell (NAcSh) in males but to both the NAc core (NAcC) and NAcSh in females. Additionally, males administered 5 mg/kg ketamine displayed increased protein expression of ΔfosB, calcium calmodulin kinase II alpha (CaMKIIα), and brain-derived neurotrophic factor (BDNF), an effect not observed in females administered either dose of ketamine. However, males and females administered 5 mg/kg ketamine displayed increased protein expression of AMPA receptors (GluA1). Taken together, low-dose ketamine, when administered intermittently, induces behavioral sensitization at a lower dose in females than males, accompanied by an increase in spine density in the NAc and protein expression changes in pathways commonly implicated in addiction. Copyright © 2017. Published by Elsevier Ltd.

Ketamine-induced inhibition of glycogen synthase kinase-3 contributes to the augmentation of α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor signaling.

PubMed

Beurel, Eléonore; Grieco, Steven F; Amadei, Celeste; Downey, Kimberlee; Jope, Richard S

2016-09-01

Sub-anesthetic doses of ketamine have been found to provide rapid antidepressant actions, indicating that the cellular signaling systems targeted by ketamine are potential sites for therapeutic intervention. Ketamine acts as an antagonist of N-methyl-D-aspartate (NMDA) receptors, and animal studies indicate that subsequent augmentation of signaling by α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors is critical for the antidepressant outcome. In this study, we tested if the inhibitory effect of ketamine on glycogen synthase kinase-3 (GSK3) affected hippocampal cell-surface AMPA receptors using immunoblotting of membrane and synaptosomal extracts from wild-type and GSK3 knockin mice. Treatment with an antidepressant dose of ketamine increased the hippocampal membrane level of the AMPA glutamate receptor (GluA)1 subunit, but did not alter the localization of GluA2, GluA3, or GluA4. This effect of ketamine was abrogated in GSK3 knockin mice expressing mutant GSK3 that cannot be inhibited by ketamine, demonstrating that ketamine-induced inhibition of GSK3 is necessary for up-regulation of cell surface AMPA GluA1 subunits. AMPA receptor trafficking is regulated by post-synaptic density-95 (PSD-95), a substrate for GSK3. Ketamine treatment decreased the hippocampal membrane level of phosphorylated PSD-95 on Thr-19, the target of GSK3 that promotes AMPA receptor internalization. These results demonstrate that ketamine-induced inhibition of GSK3 causes reduced phosphorylation of PSD-95, diminishing the internalization of AMPA GluA1 subunits to allow for augmented signaling through AMPA receptors following ketamine treatment. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Ketamine-induced inhibition of glycogen synthase kinase-3 contributes to the augmentation of AMPA receptor signaling

PubMed Central

Beurel, Eléonore; Grieco, Steven F; Amadei, Celeste; Downey, Kimberlee; Jope, Richard S

2016-01-01

Objectives Sub-anesthetic doses of ketamine have been found to provide rapid antidepressant actions, indicating that the cellular signaling systems targeted by ketamine are potential sites for therapeutic intervention. Ketamine acts as an antagonist of N-methyl-D-aspartate (NMDA) receptors, and animal studies indicate that subsequent augmentation of signaling by α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors is critical for the antidepressant outcome. Methods In this study, we tested if the inhibitory effect of ketamine on glycogen synthase kinase-3 (GSK3) affected hippocampal cell-surface AMPA receptors using immunoblotting of membrane and synaptosomal extracts from wild-type and GSK3 knockin mice. Results Treatment with an antidepressant dose of ketamine increased the hippocampal membrane level of the AMPA glutamate receptor (GluA)1 subunit, but did not alter the localization of GluA2, GluA3, or GluA4. This effect of ketamine was abrogated in GSK3 knockin mice expressing mutant GSK3 that cannot be inhibited by ketamine, demonstrating that ketamine-induced inhibition of GSK3 is necessary for up-regulation of cell surface AMPA GluA1 subunits. AMPA receptor trafficking is regulated by post-synaptic density-95 (PSD-95), a substrate for GSK3. Ketamine treatment decreased the hippocampal membrane level of phosphorylated PSD-95 on Thr-19, the target of GSK3 that promotes AMPA receptor internalization. Conclusions These results demonstrate that ketamine-induced inhibition of GSK3 causes reduced phosphorylation of PSD-95, diminishing the internalization of AMPA GluA1 subunits to allow for augmented signaling through AMPA receptors following ketamine treatment. PMID:27687706

Ventral CA3 Activation Mediates Prophylactic Ketamine Efficacy Against Stress-Induced Depressive-like Behavior.

PubMed

Mastrodonato, Alessia; Martinez, Randy; Pavlova, Ina P; LaGamma, Christina T; Brachman, Rebecca A; Robison, Alfred J; Denny, Christine A

2018-02-23

We previously reported that a single injection of ketamine prior to stress protects against the onset of depressive-like behavior and attenuates learned fear. However, the molecular pathways and brain circuits underlying ketamine-induced stress resilience are still largely unknown. Here, we tested whether prophylactic ketamine administration altered neural activity in the prefrontal cortex and/or hippocampus. Mice were injected with saline or ketamine (30 mg/kg) 1 week before social defeat. Following behavioral tests assessing depressive-like behavior, mice were sacrificed and brains were processed to quantify ΔFosB expression. In a second set of experiments, mice were stereotaxically injected with viral vectors into ventral CA3 (vCA3) in order to silence or overexpress ΔFosB prior to prophylactic ketamine administration. In a third set of experiments, ArcCreER T2 mice, a line that allows for the indelible labeling of neural ensembles activated by a single experience, were used to quantify memory traces representing a contextual fear conditioning experience following prophylactic ketamine administration. Prophylactic ketamine administration increased ΔFosB expression in the ventral dentate gyrus and vCA3 of social defeat mice but not of control mice. Transcriptional silencing of ΔFosB activity in vCA3 inhibited prophylactic ketamine efficacy, while overexpression of ΔFosB mimicked and occluded ketamine's prophylactic effects. In ArcCreER T2 mice, ketamine administration altered memory traces representing the contextual fear conditioning experience in vCA3 but not in the ventral dentate gyrus. Our data indicate that prophylactic ketamine may be protective against a stressor by altering neural activity, specifically the neural ensembles representing an individual stressor in vCA3. Copyright © 2018 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Distinct effects of ketamine and acetyl l-carnitine on the dopamine system in zebrafish

PubMed Central

Robinson, Bonnie L.; Dumas, Melanie; Cuevas, Elvis; Gu, Qiang; Paule, Merle G.; Ali, Syed F.; Kanungo, Jyotshna

2016-01-01

Ketamine, a noncompetitive N-methyl-d-aspartic acid (NMDA) receptor antagonist is commonly used as a pediatric anesthetic. We have previously shown that acetyl L-carnitine (ALCAR) prevents ketamine toxicity in zebrafish embryos. In mammals, ketamine is known to modulate the dopaminergic system. NMDA receptor antagonists are considered as promising anti-depressants, but the exact mechanism of their function is unclear. Here, we measured the levels of dopamine (DA) and its metabolites, 3, 4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in the zebrafish embryos exposed to ketamine in the presence and absence of 0.5 mM ALCAR. Ketamine, at lower doses (0.1–0.3 mM), did not produce significant changes in DA, DOPAC or HVA levels in 52 h post-fertilization embryos treated for 24 h. In these embryos, tyrosine hydroxylase (TH) mRNA expression remained unchanged. However, 2 mM ketamine (internal embryo exposure levels equivalent to human anesthetic plasma concentration) significantly reduced DA level and TH mRNA indicating that DA synthesis was adversely affected. In the presence or absence of 2 mM ketamine, ALCAR showed similar effects on DA level and TH mRNA, but increased DOPAC level compared to control. ALCAR reversed 2 mM ketamine-induced reduction in HVA levels. With ALCAR alone, the expression of genes encoding the DA metabolizing enzymes, MAO (monoamine oxidase) and catechol-O-methyltransferase (COMT), was not affected. However, ketamine altered MAO mRNA expression, except at the 0.1 mM dose. COMT transcripts were reduced in the 2 mM ketamine-treated group. These distinct effects of ketamine and ALCAR on the DA system may shed some light on the mechanism on how ketamine can work as an anti-depressant, especially at sub-anesthetic doses that do not affect DA metabolism and suppress MAO gene expression. PMID:26898327

Ketamine Exhibits Different Neuroanatomical Profile After Mammalian Target of Rapamycin Inhibition in the Prefrontal Cortex: the Role of Inflammation and Oxidative Stress.

PubMed

Abelaira, Helena M; Réus, Gislaine Z; Ignácio, Zuleide M; Dos Santos, Maria Augusta B; de Moura, Airam B; Matos, Danyela; Demo, Júlia P; da Silva, Júlia B I; Danielski, Lucineia G; Petronilho, Fabricia; Carvalho, André F; Quevedo, João

2017-09-01

Studies indicated that mammalian target of rapamycin (mTOR), oxidative stress, and inflammation are involved in the pathophysiology of major depressive disorder (MDD). Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has been identified as a novel MDD therapy; however, the antidepressant mechanism is not fully understood. In addition, the effects of ketamine after mTOR inhibition have not been fully investigated. In the present study, we examined the behavioral and biochemical effects of ketamine in the prefrontal cortex (PFC), hippocampus, amygdala, and nucleus accumbens after inhibition of mTOR signaling in the PFC. Male adult Wistar rats received pharmacological mTOR inhibitor, rapamycin (0.2 nmol) or vehicle into the PFC and then a single dose of ketamine (15 mg/kg, i.p.). Immobility was assessed in forced swimming tests, and then oxidative stress parameters and inflammatory markers were evaluated in the brain and periphery. mTOR activation in the PFC was essential to ketamine's antidepressant-like effects. Ketamine increased lipid damage in the PFC, hippocampus, and amygdala. Protein carbonyl was elevated in the PFC, amygdala, and NAc after ketamine administration. Ketamine also increased nitrite/nitrate in the PFC, hippocampus, amygdala, and NAc. Myeloperoxidase activity increased in the hippocampus and NAc after ketamine administration. The activities of superoxide dismutase and catalase were reduced after ketamine administration in all brain areas studied. Inhibition of mTOR signaling pathways by rapamycin in the PFC was required to protect against oxidative stress by reducing damage and increasing antioxidant enzymes. Finally, the TNF-α level was increased in serum by ketamine; however, the rapamycin plus treatment group was not able to block this increase. Activation of mTOR in the PFC is involved in the antidepressant-like effects of ketamine; however, the inhibition of this pathway was able to protect certain brain areas against oxidative stress, without affecting inflammation parameters.

Ketamine attenuates the glutamatergic neurotransmission in the ventral posteromedial nucleus slices of rats.

PubMed

Fu, Bao; Liu, Chengxi; Zhang, Yajun; Fu, Xiaoyun; Zhang, Lin; Yu, Tian

2017-08-23

Ketamine is a frequently used intravenous anesthetic, which can reversibly induce loss of consciousness (LOC). Previous studies have demonstrated that thalamocortical system is critical for information transmission and integration in the brain. The ventral posteromedial nucleus (VPM) is a critical component of thalamocortical system. Glutamate is an important excitatory neurotransmitter in the brain and may be involved in ketamine-induced LOC. The study used whole-cell patch-clamp to observe the effect of ketamine (30 μM-1000 μM) on glutamatergic neurotransmission in VPM slices. Ketamine significantly decreased the amplitude of glutamatergic spontaneous excitatory postsynaptic currents (sEPSCs), but only higher concentration of ketamine (300 μM and 1000 μM) suppressed the frequency of sEPSCs. Ketamine (100 μM-1000 μM) also decreased the amplitude of glutamatergic miniature excitatory postsynaptic currents (mEPSCs), without altering the frequency. In VPM neurons, ketamine attenuates the glutamatergic neurotransmission mainly through postsynaptic mechanism and action potential may be involved in the process.

Ketamine impairs recognition memory consolidation and prevents learning-induced increase in hippocampal brain-derived neurotrophic factor levels.

PubMed

Goulart, B K; de Lima, M N M; de Farias, C B; Reolon, G K; Almeida, V R; Quevedo, J; Kapczinski, F; Schröder, N; Roesler, R

2010-06-02

The non-competitive N-methyl-d-aspartate (NMDA) glutamate receptor antagonist ketamine has been shown to produce cognitive deficits. However, the effects of ketamine on the consolidation phase of memory remain poorly characterized. Here we show that systemic administration of ketamine immediately after training dose-dependently impairs long-term retention of memory for a novel object recognition (NOR) task in rats. Control experiments showed that the impairing effects of ketamine could not be attributed to an influence on memory retrieval or sensorimotor effects. In addition, ketamine prevented the increase in hippocampal brain-derived neurotrophic factor (BDNF) levels induced by NOR learning. Our results show for the first time that ketamine disrupts the consolidation phase of long-term recognition memory. In addition, the findings suggest that the amnestic effects of ketamine might be at least partially mediated by an influence on BDNF signaling in the hippocampus. Copyright 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Ketamine and ketamine metabolites as novel estrogen receptor ligands: Induction of cytochrome P450 and AMPA glutamate receptor gene expression.

PubMed

Ho, Ming-Fen; Correia, Cristina; Ingle, James N; Kaddurah-Daouk, Rima; Wang, Liewei; Kaufmann, Scott H; Weinshilboum, Richard M

2018-04-03

Major depressive disorder (MDD) is the most common psychiatric illness worldwide, and it displays a striking sex-dependent difference in incidence, with two thirds of MDD patients being women. Ketamine treatment can produce rapid antidepressant effects in MDD patients, effects that are mediated-at least partially-through glutamatergic neurotransmission. Two active metabolites of ketamine, (2R,6R)-hydroxynorketamine (HNK) and (2S,6S)-HNK, also appear to play a key role in ketamine's rapid antidepressant effects through the activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors. In the present study, we demonstrated that estrogen plus ketamine or estrogen plus active ketamine metabolites displayed additive effects on the induction of the expression of AMPA receptor subunits. In parallel, the expression of estrogen receptor alpha (ERα) was also significantly upregulated. Even more striking, radioligand binding assays demonstrated that [ 3 H]-ketamine can directly bind to ERα (K D : 344.5 ± 13 nM). Furthermore, ketamine and its (2R,6R)-HNK and (2S,6S)-HNK metabolites displayed similar affinity for ERα (IC 50 : 2.31 ± 0.1, 3.40 ± 0.2, and 3.53 ± 0.2 µM, respectively) as determined by [ 3 H]-ketamine displacement assays. Finally, induction of AMPA receptors by either estrogens or ketamine and its metabolites was lost when ERα was knocked down or silenced pharmacologically. These results suggest a positive feedback loop by which estrogens can augment the effects of ketamine and its (2R,6R)-HNK and (2S,6S)-HNK metabolites on the ERα-induced transcription of CYP2A6 and CYP2B6, estrogen inducible enzymes that catalyze ketamine's biotransformation to form the two active metabolites. These observations provide novel insight into ketamine's molecular mechanism(s) of action and have potential implications for the treatment of MDD. Copyright © 2018 Elsevier Inc. All rights reserved.

A PK-PD Model of Ketamine-Induced High-Frequency Oscillations

PubMed Central

Flores, Francisco J.; Ching, ShiNung; Hartnack, Katharine; Fath, Amanda B.; Purdon, Patrick L.; Wilson, Matthew A.; Brown, Emery N.

2017-01-01

Objective Ketamine is a widely used drug with clinical and research applications, and also known to be used as a recreational drug. Ketamine produces conspicuous changes in the electrocorticographic (ECoG) signals observed both in humans and rodents. In rodents, the intracranial ECoG displays a High-Frequency Oscillation (HFO) which power is modulated non-linearly by ketamine dose. Despite the widespread use of ketamine there is no model description of the relationship between the pharmacokinetic-pharmacodynamics (PK-PD) of ketamine and the observed HFO power. Approach In the present study, we developed a PK-PD model based on estimated ketamine concentration, its known pharmacological actions, and observed ECoG effects. The main pharmacological action of ketamine is antagonism of the NMDA receptor (NMDAR), which in rodents is accompanied by a high-frequency oscillation (HFO) observed in the ECoG. At high doses, however, ketamine also acts at non-NMDAR sites, produces loss of consciousness, and the transient disappearance of the HFO. We propose a two-compartment PK model that represents the concentration of ketamine, and a PD model based in opposing effects of the NMDAR and non-NMDAR actions on the HFO power. Main results We recorded ECoG from the cortex of rats after two doses of ketamine, and extracted the HFO power from the ECoG spectrograms. We fit the PK-PD model to the time course of the HFO power, and showed that the model reproduces the dose-dependent profile of the HFO power. The model provides good fits even in the presence of high variability in HFO power across animals. As expected, the model does not provide good fits to the HFO power after dosing the pure NMDAR antagonist MK-801. Significance Our study provides a simple model to relate the observed electrophysiological effects of ketamine to its actions at the molecular level at different concentrations. This will improve the study of ketamine and rodent models of schizophrenia to better understand the wide and divergent range of effects that ketamine has. PMID:26268223

Abnormalities in white matter microstructure associated with chronic ketamine use.

PubMed

Edward Roberts, R; Curran, H Valerie; Friston, Karl J; Morgan, Celia J A

2014-01-01

Ketamine is an N-methyl-D-aspartate (NMDA) receptor antagonist that has been found to induce schizophrenia-type symptoms in humans and is a potent and fast-acting antidepressant. It is also a relatively widespread drug of abuse, particularly in China and the UK. Acute administration has been well characterized, but the effect of extended periods of ketamine use-on brain structure in humans-remains poorly understood. We measured indices of white matter microstructural integrity and connectivity in the brain of 16 ketamine users and 16 poly-drug-using controls, and we used probabilistic tractography to quantify changes in corticosubcortical connectivity associated with ketamine use. We found a reduction in the axial diffusivity profile of white matter in a right hemisphere network of white matter regions in ketamine users compared with controls. Within the ketamine-user group, we found a significant positive association between the connectivity profile between the caudate nucleus and the lateral prefrontal cortex and dissociative experiences. These findings suggest that chronic ketamine use may be associated with widespread disruption of white matter integrity, and white matter pathways between subcortical and prefrontal cortical areas may in part predict individual differences in dissociative experiences due to ketamine use.

Pharmacokinetics of ketamine and norketamine enantiomers after racemic or S-ketamine IV bolus administration in dogs during sevoflurane anaesthesia.

PubMed

Romagnoli, Noemi; Bektas, Rima N; Kutter, Annette P; Barbarossa, Andrea; Roncada, Paola; Hartnack, Sonja; Bettschart-Wolfensberger, Regula

2017-06-01

The aims of this study were to measure plasma levels of R- and S-ketamine and their major metabolites R- and S-norketamine following single intravenous bolus administration of racemic or S-ketamine in sevoflurane anaesthetised dogs and to calculate the relevant pharmacokinetic profiles. Six adult healthy beagle dogs were used in the study. An intravenous bolus of 4mg/kg racemic ketamine (RS-KET) or 2mg/kg S-ketamine (S-KET) was administered, with a three-weeks washout period between treatments. Venous blood samples were collected at fixed times until 900min and R- and S-ketamine as well as R- and S-norketamine plasma levels determined by liquid chromatography coupled with tandem mass spectrometry. Cardiovascular parameters were recorded during the anaesthesia until 240min. All dogs recovered well from anaesthesia. No statistical differences between groups were detected in any cardiovascular parameter. The pharmacokinetics of S-ketamine did not differ when injected intravenously alone or as part of the racemic mixture in dogs anaesthetised with sevoflurane. Following racemic ketamine, the area under the curve of R-norketamine was statistically higher than the one of S-norketamine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Role of ketamine in acute postoperative pain management: a narrative review.

PubMed

Radvansky, Brian M; Shah, Khushbu; Parikh, Anant; Sifonios, Anthony N; Le, Vanny; Eloy, Jean D

2015-01-01

The objective of this narrative review was to examine the usage of ketamine as a postoperative analgesic agent across a wide variety of surgeries. A literature search was performed using the phrases "ketamine" and "postoperative pain." The authors analyzed the studies that involved testing ketamine's effectiveness at controlling postoperative pain. Effectiveness was assessed through various outcomes such as the amount of opiate consumption, visual analog scale (VAS) pain scores, and persistent postoperative pain at long-term follow-up. While many different administration protocols were evaluated, delivering ketamine both as a pre- or perioperative bolus and postoperative infusion for up to 48 hours appeared to be the most effective. These effects are dose-dependent. However, a number of studies analyzed showed no benefit in using ketamine versus placebo for controlling postoperative pain. While ketamine is a safe and well-tolerated drug, it does have adverse effects, and there are concerns for possible neurotoxicity and effects on memory. In a number of limited situations, ketamine has shown some efficacy in controlling postoperative pain and decreasing opioid consumption. More randomized controlled trials are necessary to determine the surgical procedures and administrations (i.e., intravenous, epidural) that ketamine is best suited for.

Prenatal ketamine exposure causes abnormal development of prefrontal cortex in rat

PubMed Central

Zhao, Tianyun; Li, Chuanxiang; Wei, Wei; Zhang, Haixing; Ma, Daqing; Song, Xingrong; Zhou, Libing

2016-01-01

Ketamine is commonly used for anesthesia and as a recreational drug. In pregnant users, a potential neurotoxicity in offspring has been noted. Our previous work demonstrated that ketamine exposure of pregnant rats induces affective disorders and cognitive impairments in offspring. As the prefrontal cortex (PFC) is critically involved in emotional and cognitive processes, here we studied whether maternal ketamine exposure influences the development of the PFC in offspring. Pregnant rats on gestational day 14 were treated with ketamine at a sedative dose for 2 hrs, and pups were studied at postnatal day 0 (P0) or P30. We found that maternal ketamine exposure resulted in cell apoptosis and neuronal loss in fetal brain. Upon ketamine exposure in utero, PFC neurons at P30 showed more dendritic branching, while cultured neurons from P0 PFC extended shorter neurites than controls. In addition, maternal ketamine exposure postponed the switch of NR2B/2A expression, and perturbed pre- and postsynaptic protein expression in the PFC. These data suggest that prenatal ketamine exposure impairs neuronal development of the PFC, which may be associated with abnormal behavior in offsprings. PMID:27226073

Ketamine for cancer pain: what is the evidence?

PubMed

Jonkman, Kelly; van de Donk, Tine; Dahan, Albert

2017-06-01

In this review, we assess the benefit of ketamine in the treatment of terminal cancer pain that is refractory to opioid treatment and/or complicated by neuropathy. While randomized controlled trials consistently show lack of clinical efficacy of ketamine in treating cancer pain, a large number of open-label studies and case series show benefit. Ketamine is an N-methyl-D-aspartate receptor antagonist that at low-dose has effective analgesic properties. In cancer pain, ketamine is usually prescribed as adjuvant to opioid therapy when pain becomes opioid resistant or when neuropathic pain symptoms dominate the clinical picture. A literature search revealed four randomized controlled trials that examined the benefit of oral, subcutaneous or intravenous ketamine in opioid refractory cancer pain. None showed clinically relevant benefit in relieving pain or reducing opioid consumption. This suggests absence of evidence of benefit for ketamine as adjuvant analgesic in cancer pain. These findings contrast the benefit from ketamine observed in a large number of open-label studies and (retrospective) case series. We relate the opposite outcomes to methodological issues. The complete picture is such that there is still insufficient evidence to state with certainty that ketamine is not effective in cancer pain.

Despite irreversible binding, PET tracer [11C]-SA5845 is suitable for imaging of drug competition at sigma receptors-the cases of ketamine and haloperidol.

PubMed

Kortekaas, Rudie; Maguire, R Paul; van Waarde, Aren; Leenders, Klaus L; Elsinga, Philip H

2008-07-01

Many psychotropic compounds bind to sigma receptors and several new sigma ligands are in development for psychiatric indications such as anxiety, attention deficit hyperactivity disorder, depression and psychosis. Of special interest for drug development are tomographic methods that can quantify the binding of promising sigma ligands in a regional manner. Here we present the development of such a method and the first evaluation of sigma ligand [11C]-SA5845 in a primate. Extensive pharmacokinetic modeling was done on tissue curves and a heart lumen curve. The effects of pretreatment and challenge with haloperidol were studied as well as those of pretreatment with +/- -ketamine. The tracer had a plasma half-life of 77+/-1.7min and was rapidly taken up by all brain areas. The binding pattern was consistent with binding to sigma receptors and compartment modeling showed there was considerable specific binding that was irreversible. We therefore calculated the net influx rate, Ki, with the Gjedde-Patlak linearization, as a measure of free receptors. As expected, Ki was very sensitive to the presence of competing ligands - -ketamine and/or haloperidol. Summarizing, the tracer is well suited for visualizing sigma receptors in the brain and moreover, the presented method is able to quantify, on a regional basis, specific binding of unlabeled ligands to sigma receptors.

New Hippocampal Neurons Mature Rapidly in Response to Ketamine But Are Not Required for Its Acute Antidepressant Effects on Neophagia in Rats123

PubMed Central

Soumier, Amelie; Carter, Rayna M.; Schoenfeld, Timothy J.

2016-01-01

Abstract Virtually all antidepressant agents increase the birth of granule neurons in the adult dentate gyrus in rodents, providing a key basis for the neurogenesis hypothesis of antidepressant action. The novel antidepressant ketamine, however, shows antidepressant activity in humans within hours, far too rapid for a mechanism involving neuronal birth. Ketamine could potentially act more rapidly by enhancing maturation of new neurons born weeks earlier. To test this possibility, we assessed the effects of S-ketamine (S-(+)-ketamine hydrochloride) injection on maturation, as well as birth and survival, of new dentate gyrus granule neurons in rats, using the immediate-early gene zif268, proliferating cell nuclear antigen, and BrdU, respectively. We show that S-ketamine has rapid effects on new neurons, increasing the proportion of functionally mature young granule neurons within 2 h. A single injection of S-ketamine also increased cell proliferation and functional maturation, and decreased depressive-like behavior, for at least 4 weeks in rats treated with long-term corticosterone administration (a depression model) and controls. However, the behavioral effects of S-ketamine on neophagia were unaffected by elimination of adult neurogenesis. Together, these results indicate that ketamine has surprisingly rapid and long-lasting effects on the recruitment of young neurons into hippocampal networks, but that ketamine has antidepressant-like effects that are independent of adult neurogenesis. PMID:27066531

Longitudinal Effects of Ketamine on Dendritic Architecture In Vivo in the Mouse Medial Frontal Cortex123

PubMed Central

Phoumthipphavong, Victoria; Barthas, Florent; Hassett, Samantha

2016-01-01

Abstract A single subanesthetic dose of ketamine, an NMDA receptor antagonist, leads to fast-acting antidepressant effects. In rodent models, systemic ketamine is associated with higher dendritic spine density in the prefrontal cortex, reflecting structural remodeling that may underlie the behavioral changes. However, turnover of dendritic spines is a dynamic process in vivo, and the longitudinal effects of ketamine on structural plasticity remain unclear. The purpose of the current study is to use subcellular resolution optical imaging to determine the time course of dendritic alterations in vivo following systemic ketamine administration in mice. We used two-photon microscopy to visualize repeatedly the same set of dendritic branches in the mouse medial frontal cortex (MFC) before and after a single injection of ketamine or saline. Compared to controls, ketamine-injected mice had higher dendritic spine density in MFC for up to 2 weeks. This prolonged increase in spine density was driven by an elevated spine formation rate, and not by changes in the spine elimination rate. A fraction of the new spines following ketamine injection was persistent, which is indicative of functional synapses. In a few cases, we also observed retraction of distal apical tuft branches on the day immediately after ketamine administration. These results indicate that following systemic ketamine administration, certain dendritic inputs in MFC are removed immediately, while others are added gradually. These dynamic structural modifications are consistent with a model of ketamine action in which the net effect is a rebalancing of synaptic inputs received by frontal cortical neurons. PMID:27066532

Revealing past memories: proactive interference and ketamine-induced memory deficits.

PubMed

Chrobak, James J; Hinman, James R; Sabolek, Helen R

2008-04-23

Memories of events that occur often are sensitive to interference from memories of similar events. Proactive interference plays an important and often unexamined role in memory testing for spatially and temporally unique events ("episodes"). Ketamine (NMDA receptor antagonist) treatment in humans and other mammals induces a constellation of cognitive deficits, including impairments in working and episodic memory. We examined the effects of the ketamine (2.5-100 mg/kg) on the acquisition, retrieval, and retention of memory in a delayed-match-to-place radial water maze task that can be used to assess proactive interference. Ketamine (2.5-25 mg/kg, i.p.) given 20 min before the sample trial, impaired encoding. The first errors made during the test trial were predominantly to arms located spatially adjacent to the goal arm, suggesting an established albeit weakened representation. Ketamine (25-100 mg/kg) given immediately after the sample trial had no effect on retention. Ketamine given before the test trial impaired retrieval. First errors under the influence of ketamine were predominantly to the goal location of the previous session. Thus, ketamine treatment promoted proactive interference. These memory deficits were not state dependent, because ketamine treatment at both encoding and retrieval only increased the number of errors during the test session. These data demonstrate the competing influence of distinct memory representations during the performance of a memory task in the rat. Furthermore, they demonstrate the subtle disruptive effects of the NMDA antagonist ketamine on both encoding and retrieval. Specifically, ketamine treatment disrupted retrieval by promoting proactive interference from previous episodic representations.

Rapamycin blocks the antidepressant effect of ketamine in task-dependent manner.

PubMed

Holubova, Kristina; Kleteckova, Lenka; Skurlova, Martina; Ricny, Jan; Stuchlik, Ales; Vales, Karel

2016-06-01

The aim of our study was to test whether ketamine produces an antidepressant effect in animal model of olfactory bulbectomy and assess the role of mammalian target of rapamycin (mTOR) pathway in ketamine's antidepressant effect. Bulbectomized (OBX) rats and sham controls were assigned to four subgroups according to the treatment they received (ketamine, saline, ketamine + rapamycin, and saline + rapamycin). The animals were subjected to open field (OF), elevated plus maze (EPM), passive avoidance (PA), Morris water maze (MWM), and Carousel maze (CM) tests. Blood samples were collected before and after drug administration for analysis of phosphorylated mTOR level. After behavioral testing, brains were removed for evaluation of brain-derived neurotrophic factor (BDNF) in prefrontal cortex (PFC) and hippocampus. Ketamine normalized hyperactivity of OBX animals in EPM and increased the time spent in open arms. Rapamycin pretreatment resulted in elimination of ketamine effect in EPM test. In CM test, ketamine + rapamycin administration led to cognitive impairment not observed in saline-, ketamine-, or saline + rapamycin-treated OBX rats. Prefrontal BDNF content was significantly decreased, and level of mTOR was significantly elevated in OBX groups. OBX animals significantly differed from sham controls in most of the tests used. Treatment had more profound effect on OBX phenotype than controls. Pretreatment with rapamycin eliminated the anxiolytic and antidepressant effects of ketamine in task-dependent manner. The results indicate that ketamine + rapamycin application resulted in impaired stress responses manifested by cognitive deficits in active place avoidance (CM) test. Intensity of stressor (mild vs. severe) used in the behavioral tests had opposite effect on controls and on OBX animals.

Mechanisms underlying differential effectiveness of memantine and ketamine in rapid antidepressant responses

PubMed Central

Gideons, Erinn S.; Kavalali, Ege T.; Monteggia, Lisa M.

2014-01-01

Ketamine is an NMDA receptor (NMDAR) antagonist that elicits rapid antidepressant responses in patients with treatment-resistant depression. However, ketamine can also produce psychotomimetic effects that limit its utility as an antidepressant, raising the question of whether the clinically tolerated NMDAR antagonist memantine possesses antidepressant properties. Despite its similar potency to ketamine as an NMDAR antagonist, clinical data suggest that memantine does not exert rapid antidepressant actions for reasons that are poorly understood. In this study, we recapitulate the ketamine and memantine clinical findings in mice, showing that ketamine, but not memantine, has antidepressant-like effects in behavioral models. Using electrophysiology in cultured hippocampal neurons, we show that ketamine and memantine effectively block NMDAR-mediated miniature excitatory postsynaptic currents in the absence of Mg2+. However, in physiological levels of extracellular Mg2+, we identified key functional differences between ketamine and memantine in their ability to block NMDAR function at rest. This differential effect of ketamine and memantine extends to intracellular signaling coupled to NMDAR at rest, in that memantine does not inhibit the phosphorylation of eukaryotic elongation factor 2 or augment subsequent expression of BDNF, which are critical determinants of ketamine-mediated antidepressant efficacy. These results demonstrate significant differences between the efficacies of ketamine and memantine on NMDAR-mediated neurotransmission that have impacts on downstream intracellular signaling, which we hypothesize is the trigger for rapid antidepressant responses. These data provide a novel framework on the necessary functional requirements of NMDAR-mediated neurotransmission as a critical determinant necessary to elicit rapid antidepressant responses. PMID:24912158

21 CFR 522.1222a - Ketamine.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ketamine. 522.1222a Section 522.1222a Food and..., FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222a Ketamine. (a) Specifications. Each milliliter contains ketamine hydrochloride equivalent to 100 milligrams (mg...

21 CFR 522.1222a - Ketamine.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ketamine. 522.1222a Section 522.1222a Food and..., FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222a Ketamine. (a) Specifications. Each milliliter contains ketamine hydrochloride equivalent to 100 milligrams (mg...

21 CFR 522.1222a - Ketamine.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ketamine. 522.1222a Section 522.1222a Food and..., FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222a Ketamine. (a) Specifications. Each milliliter contains ketamine hydrochloride equivalent to 100 milligrams (mg...

21 CFR 522.1222a - Ketamine.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ketamine. 522.1222a Section 522.1222a Food and..., FEEDS, AND RELATED PRODUCTS IMPLANTATION OR INJECTABLE DOSAGE FORM NEW ANIMAL DRUGS § 522.1222a Ketamine. (a) Specifications. Each milliliter contains ketamine hydrochloride equivalent to 100 milligrams (mg...

Ketamine in the treatment of acute pain.

PubMed

Brinck, Elina; Kontinen, Vesa

2017-01-01

Ketamine is an old anesthetic agent that relieves pain by reducing central sensitization in the central nervous system. This is advantageous for patients suffering from severe pain prior to surgery or are using a strong opioid. The S enantiomer of ketamine used for anesthesia is more powerful than racemic ketamine. The ideal dose of ketamine for pain relief is not yet known, and its adverse effects on the central nervous system, including hallucinations, sedation, and diplopia have limited its use in pain management. The significance of these effects at low doses is probably less than expected, particularly if benzodiazepines or an alpha-2 agonist, such as dexmedetomidine, are administered in addition to ketamine.

Ketamine rapidly relieves acute suicidal ideation in cancer patients: a randomized controlled clinical trial.

PubMed

Fan, Wei; Yang, HaiKou; Sun, Yong; Zhang, Jun; Li, Guangming; Zheng, Ying; Liu, Yi

2017-01-10

This study was designed to examine the rapid antidepressant effects of single dose ketamine on suicidal ideation and overall depression level in patients with newly-diagnosed cancer. Forty-two patients were enrolled into the controlled trial and randomized into two groups: ketamine group and midazolam group. Patients from the two groups received a sub-anesthetic dose of racemic ketamine hydrochloride or midazolam. Suicidal ideation score, measured with the Beck Scale and suicidal part of the Montgomery-Asberg Depression Rating Scale, significantly decreased on day 1 and day 3 in ketamine-treated patients when compared to those treated with midazolam. Consistently, overall depression levels measured using the Montgomery-Asberg Depression Rating Scale indicated a significant relief of overall depression on day 1 in ketamine-treated patients. Collectively, this study provides novel information about the rapid antidepressant effect of ketamine on acute depression and suicidal ideation in newly-diagnosed cancer patients.

Role of NMDA receptor GluN2D subunit in the antidepressant effects of enantiomers of ketamine.

PubMed

Ide, Soichiro; Ikekubo, Yuiko; Mishina, Masayoshi; Hashimoto, Kenji; Ikeda, Kazutaka

2017-11-01

We investigated the rapid and sustained antidepressant effects of enantiomers of ketamine in N-methyl-d-aspartate (NMDA) receptor GluN2D subunit knockout (GluN2D-KO) mice. Intraperitoneal administration of ketamine or its enantiomers 10 min before the tail-suspension test exerted significant antidepressant effects on restraint stress-induced depression in both wildtype and GluN2D-KO mice. The antidepressant effects of (RS)-ketamine and (S)-ketamine were sustained 96 h after the injection in both wildtype and GluN2D-KO mice, but such sustained antidepressant effects of (R)-ketamine were only observed in wildtype mice. These data suggest that the GluN2D subunit is critical for the sustained antidepressant effects of (R)-ketamine. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

21 CFR 522.23 - Acepromazine.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Nos. 000010 and 000859 in § 510.600(c) of this chapter: (c) Conditions of use in dogs, cats, and horses—(1) Amount. Dogs: 0.25 to 0.5 mg per pound (/lb) of body weight; Cats: 0.5 to 1.0 mg/lb of body...

Comparative Investigation of Protective Effects of Metyrosine and Metoprolol Against Ketamine Cardiotoxicity in Rats.

PubMed

Ahiskalioglu, Ali; Ince, Ilker; Aksoy, Mehmet; Ahiskalioglu, Elif Oral; Comez, Mehmet; Dostbil, Aysenur; Celik, Mine; Alp, Hamit Hakan; Coskun, Resit; Taghizadehghalehjoughi, Ali; Suleyman, Bahadir

2015-10-01

This study investigated the effect of metyrosine against ketamine-induced cardiotoxicity in rats and compared the results with the effect of metoprolol. In this study, rats were divided into groups A, B and C. In group A, we investigated the effects of a single dose of metyrosine (150 mg/kg) and metoprolol (20 mg/kg) on single dose ketamine (60 mg/kg)-induced cardiotoxicity. In group B, we investigated the effect of metyrosine and metoprolol, which were given together with ketamine for 30 days. In group C, we investigated the effect of metyrosine and metoprolol given 15 days before ketamine and 30 days together with ketamine on ketamine cardiotoxicity. By the end of this process, we evaluated the effects of the levels of oxidant-antioxidant parameters such as MDA, MPO, 8-OHGua, tGSH, and SOD in addition to CK-MB and TP I on cardiotoxicity in rat heart tissue. The experimental results show that metyrosine prevented ketamine cardiotoxicity in groups A, B and C and metoprolol prevented it in only group C.

Hippocampal Perineuronal Nets Are Required for the Sustained Antidepressant Effect of Ketamine.

PubMed

Donegan, Jennifer J; Lodge, Daniel J

2017-04-01

N-methyl-D-aspartate receptor antagonists, like ketamine, produce a rapid-acting and long-lasting antidepressant effect. Although the mechanism is not completely understood, ketamine is thought to preferentially target N-methyl-D-aspartate receptors on fast-spiking parvalbumin-containing interneurons. The function of parvalbumin-containing interneurons is dependent on perineuronal nets, a specialized form of extracellular matrix that surrounds these cells. Chondroitinase was used to enzymatically degrade perineuronal nets surrounding parvalbumin-containing interneurons in the ventral hippocampus, a region that is involved in the antidepressant response to ketamine. Rats were tested on the forced swim test 30 minutes and 1 week after ketamine administration. Thirty minutes after ketamine injection, both chondroitinase-treated and control animals had a decrease in immobility. One week later, however, the antidepressant-like response observed with ketamine was completely abolished in the chondroitinase-treated animals. This suggests that parvalbumin interneuron function in the ventral hippocampus is essential for the sustained antidepressant effect of ketamine. © The Author 2016. Published by Oxford University Press on behalf of CINP.

Ketamine infusion for refractory status epilepticus: A case report of cardiac arrest.

PubMed

Koffman, Lauren; Yan Yiu, Ho; Farrokh, Salia; Lewin, John; Geocadin, Romergryko; Ziai, Wendy

2018-01-01

Refractory status epilepticus (RSE) has a high mortality rate and is often difficult to treat. When traditional therapies fail ketamine may be considered. There are limited reports of adverse cardiac events with the use of ketamine for RSE and no reports of cardiac arrest in this context. Evaluate the occurrence of cardiac arrhythmias associated with the use of ketamine for RSE. Retrospective chart review of nine patients who underwent ketamine infusion for RSE. Etiology of refractory status epilepticus included autoimmune/infectious process (Zeiler et al., 2014), ischemic stroke (Bleck, 2005) and subarachnoid hemorrhage (Bleck, 2005). Of the nine patients who received ketamine, two had documented cardiac events; one remained clinically stable and the other developed multiple arrhythmias, including recurrent episodes of asystole. Once ketamine was discontinued the latter patient stabilized with the addition of anti arrhythmic therapy. Ketamine is utilized to treat refractory status epilepticus, but should be used with caution in patients with subarachnoid hemorrhage, as there may be an increased risk of life threatening arrhythmias and cardiac arrest. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spinal conduction block by intrathecal ketamine in dogs.

PubMed

Iida, H; Dohi, S; Tanahashi, T; Watanabe, Y; Takenaka, M

1997-07-01

In addition to its use for intravenous (I.V.) anesthesia, ketamine can provide pain relief in humans when administered spinally. To elucidate the mechanisms of intrathecal (I.T.) ketamine analgesia, we observed differences in the effects of I.V. and I.T. ketamine on intraspinal evoked potentials (ISEPs) in 28 dogs anesthetized with pentobarbital. Bipolar extradural electrodes were inserted at the cervical and lumbar regions of the spinal cord for recording descending ISEPs represented by the two negative deflections, Waves I and II. I.V. ketamine 2 and 10 mg/ kg did not affect the amplitude and latency of Wave I, whereas the large dose (10 mg/kg) significantly decreased the amplitude but not the latency of Wave II. I.T. ketamine 1 and 5 mg/kg caused significant dose-dependent decreases in both Wave I and II amplitudes and prolongations of both Wave I and II latencies. These I.T. effects on ISEPs are consistent with previous in vitro observations that ketamine blocks axonal conduction. We conclude that axonal conduction block may contribute to the analgesic mechanism of I.T. ketamine.

Something new about ketamine for pediatric anesthesia?

PubMed

Lois, Fernande; De Kock, Marc

2008-06-01

This review discusses the place of the old anesthetic ketamine in pediatric anesthesia. Despite the availability of modern alternatives, ketamine remains a frequently used drug particularly for anesthesia in high-risk children and for procedures outside the operating room. In adult patients undergoing surgery, a renewed interest in this drug is noted. It is the consequence of recent demonstrations of the following effects. First, ketamine is highly effective against surgery and opiate-induced hyperalgesia. Second, it has original antiproinflammatory properties. In other words, it promotes self-limitation of the inflammatory response that follows surgery. In the pediatric population, these benefits wait to be confirmed. Finally, questions arise about the safety of ketamine anesthesia. Ketamine is a potent proapoptotic drug. In rodents treated during the critical period for central nervous system development, long-term behavioral deficits were noted after an anesthetic dose of ketamine. The exact consequences of these proapoptotic properties on human brain tissue development have to be exactly determined and are still debatable. Ketamine has not yet revealed all its interactions in humans. Recent discoveries indicate interesting properties on the one hand and potentially deleterious effects on the other.

[Ketamine--dreams and realities].

PubMed

Arditti, J; Spadari, M; de Haro, L; Brun, A; Bourdon, J H; Valli, M

2002-01-01

Ketamine is an anaesthetic used in human medicine and veterinary practice, synthesised on 1962 and marketed on 1970 in France. Recreational uses were described during 1992 in the medical community and in 1996 in the dance settings. The chemical name of ketamine is 2--(2chlorophenyl)2-(methylamine)-cyclohexanone, an aryl cyclohexylamine, structurally related to phencyclidine. Ketamine is known under the following street names: Keta K, Kate, Special K, Vitamin K, la Golden, la Vétérinaire. Ketamine is used intranasally, orally and intramusculary in recreational use. Ketamine is manufactured by the chemical industry. Due to the complicated synthesis, it is sold illicitly for recreational use. Ketamine is a dissociative drug, and the user enters in a psychedelic dream with hallucinations, floating sensation, feeling of dissociation of the mind from the body. The dream is forgotten, the user full in reality with loss of self control, risk of acute intoxication. In long-term exposure, tolerance, dependence, withdrawal signs and flash back are described. Ketamine trademarks are subject to control in France through medicine legislation Ketamine and its salts are subject to control under the national legislation on narcotics and psychotropics substance. From September 2001, the theft of medical and veterinary trademarks have to be declared to police, care health authority Pharmacy control authority and French Health Products Safety Agency.

How Ketamine Affects Livers of Pregnant Mice and Developing Mice?

PubMed

Cheung, Hoi Man; Chow, Tony Chin Hung; Yew, David Tai Wai

2017-05-19

It is well known that ketamine abuse can induce liver damage in adult addicts, but the effects of ketamine abuse in pregnant mothers on their offspring have received less attention. In this study, we investigated the effects of 5-day ketamine injections (30 mg/kg) to pregnant Institute for Cancer Research (ICR) mice during early gestation or mid-gestation on the aspartate aminotransferase (AST) and alkaline phosphatase (ALP) activities of the mothers and the offspring. We also looked into whether administering ketamine treatment to the mothers had any effects on the extent of fibrosis, cell proliferation and cell death in the livers of the newborns. No significant biochemical differences were found between treatment and control groups in the mothers. In the offspring, ketamine treatment mildly suppressed the gradual increase of hepatic AST activity in neonates during liver maturation. Measurements of hepatic ALP activity and lactic acid dehydrogenase (LDH) immunoreactivity revealed that ketamine treatment may lead to increased cell death. Proliferation of liver cells of the newborns was also retarded as shown by reduced proliferative cell nuclear antigen (PCNA) immunoreactivity in the ketamine groups. No obvious fibrosis was evident. Thus, we demonstrated that ketamine administration to pregnant mice suppressed hepatic development and also induced liver cell death of the offspring.

Involvement of posterior cingulate cortex in ketamine-induced psychosis relevant behaviors in rats.

PubMed

Ma, Jingyi; Leung, L Stan

2018-02-15

The involvement of posterior cingulate cortex (PCC) on ketamine-induced psychosis relevant behaviors was investigated in rats. Bilateral infusion of muscimol, a GABA A receptor agonist, into the PCC significantly antagonized ketamine-induced deficit in prepulse inhibition of a startle reflex (PPI), deficit in gating of hippocampal auditory evoked potentials, and behavioral hyperlocomotion in a dose dependent manner. Local infusion of ketamine directly into the PCC also induced a PPI deficit. Systemic injection of ketamine (3mg/kg,s.c.) induced an increase in power of electrographic activity in the gamma band (30-100Hz) in both the PCC and the hippocampus; peak theta (4-10Hz) power was not significantly altered, but peak theta frequency was increased by ketamine. In order to exclude volume conduction from the hippocampus to PCC, inactivation of the hippocampus was made by local infusion of muscimol into the hippocampus prior to ketamine administration. Muscimol in the hippocampus effectively blocked ketamine-induced increase of gamma power in the hippocampus but not in the PCC, suggesting independent generation of gamma waves in PCC and hippocampus. It is suggested that the PCC is part of the brain network mediating ketamine-induced psychosis related behaviors. Copyright © 2017 Elsevier B.V. All rights reserved.

Ketamine induces brain-derived neurotrophic factor expression via phosphorylation of histone deacetylase 5 in rats.

PubMed

Choi, Miyeon; Lee, Seung Hoon; Park, Min Hyeop; Kim, Yong-Seok; Son, Hyeon

2017-08-05

Ketamine shows promise as a therapeutic agent for the treatment of depression. The increased expression of brain-derived neurotrophic factor (BDNF) has been associated with the antidepressant-like effects of ketamine, but the mechanism of BDNF induction is not well understood. In the current study, we demonstrate that the treatment of rats with ketamine results in the dose-dependent rapid upregulation of Bdnf promoter IV activity and expression of Bdnf exon IV mRNAs in rat hippocampal neurons. Transfection of histone deacetylase 5 (HDAC5) into rat hippocampal neurons similarly induces Bdnf mRNA expression in response to ketamine, whereas transfection of a HDAC5 phosphorylation-defective mutant (Ser259 and Ser498 replaced by Ala259 and Ala498), results in the suppression of ketamine-mediated BDNF promoter IV transcriptional activity. Viral-mediated hippocampal knockdown of HDAC5 induces Bdnf mRNA and protein expression, and blocks the enhancing effects of ketamine on BDNF expression in both unstressed and stressed rats, and thereby providing evidence for the role of HDAC5 in the regulation of Bdnf expression. Taken together, our findings implicate HDAC5 in the ketamine-induced transcriptional regulation of Bdnf, and suggest that the phosphorylation of HDAC5 regulates the therapeutic actions of ketamine. Copyright © 2017 Elsevier Inc. All rights reserved.

Electroencephalogram Signatures of Ketamine-Induced Unconsciousness

PubMed Central

Akeju, Oluwaseun; Song, Andrew H.; Hamilos, Allison E.; Pavone, Kara J.; Flores, Francisco J.; Brown, Emery N.; Purdon, Patrick L.

2016-01-01

Objectives Ketamine is an N-methyl-D-aspartate receptor antagonist commonly administered as a general anesthetic. However, circuit level mechanisms to explain ketamine-induced unconsciousness in humans are yet to be clearly defined. Disruption of frontal-parietal network connectivity has been proposed as a mechanism to explain this brain state. However, this mechanism was recently demonstrated at subanesthetic doses of ketamine in awake-patients. Therefore we investigated whether there is an electroencephalogram (EEG) marker for ketamine-induced unconsciousness. Methods We retrospectively studied the EEG in 12 patients who received ketamine for the induction of general anesthesia. We analyzed the EEG dynamics using power spectral and coherence methods. Results Following the administration of a bolus dose of ketamine to induce unconsciousness, we observed a “gamma burst” EEG pattern that consisted of alternating slow-delta (0.1-4 Hz) and gamma (~27-40 Hz) oscillations. This pattern was also associated with increased theta oscillations (~4-8 Hz) and decreased alpha/beta oscillations (~10-24 Hz). Conclusions Ketamine-induced unconsciousness is associated with a gamma burst EEG pattern. Significance We postulate that the gamma burst pattern is a thalamocortical rhythm based on insights previously obtained from cat neurophysiological experiments. This EEG signature of ketamine-induced unconsciousness may offer new insights into general anesthesia induced brain states. PMID:27178861

Does intravenous ketamine enhance analgesia after arthroscopic shoulder surgery with ultrasound guided single-injection interscalene block?: a randomized, prospective, double-blind trial.

PubMed

Woo, Jae Hee; Kim, Youn Jin; Baik, Hee Jung; Han, Jong In; Chung, Rack Kyung

2014-07-01

Ketamine has anti-inflammatory, analgesic and antihyperalgesic effect and prevents pain associated with wind-up. We investigated whether low doses of ketamine infusion during general anesthesia combined with single-shot interscalene nerve block (SSISB) would potentiate analgesic effect of SSISB. Forty adult patients scheduled for elective arthroscopic shoulder surgery were enrolled and randomized to either the control group or the ketamine group. All patients underwent SSISB and followed by general anesthesia. During an operation, intravenous ketamine was infused to the patients of ketamine group continuously. In control group, patients received normal saline in volumes equivalent to ketamine infusions. Pain score by numeric rating scale was similar between groups at 1, 6, 12, 24, 36, and 48 hr following surgery, which was maintained lower than 3 in both groups. The time to first analgesic request after admission on post-anesthesia care unit was also not significantly different between groups. Intraoperative low dose ketamine did not decrease acute postoperative pain after arthroscopic shoulder surgery with a preincisional ultrasound guided SSISB. The preventive analgesic effect of ketamine could be mitigated by SSISB, which remains one of the most effective methods of pain relief after arthroscopic shoulder surgery.

First injection of ketamine among young injection drug users (IDUs) in three U.S. cities

PubMed Central

Lankenau, Stephen E.; Sanders, Bill; Bloom, Jennifer Jackson; Hathazi, Dodi; Alarcon, Erica; Tortu, Stephanie; Clatts, Michael C.

2007-01-01

Ketamine, a dissociative anesthetic, has emerged as an increasingly common drug among subgroups of young injection drug users (IDUs) in cities across the United States. In-depth qualitative interviews were conducted with 213 young IDUs aged 16–28 years recruited in New York, New Orleans, and Los Angeles between 2004 and 2006. While some initiated injection drug use with ketamine, the drug was more frequently injected by IDUs with extensive polydrug using histories. IDUs initiating with ketamine commonly self-injected via an intramuscular mode of administration. The injection group provided crucial knowledge and material resources that enabled the injection event to occur, including ketamine, syringes, and injection skills. Injection paraphernalia was commonly shared during the first injection of ketamine, particularly vials of pharmaceutically-packaged liquid ketamine. Injection events infrequently occurred in a rave or club and more typically in a private home, which challenges ketamine’s designation as a ‘club’ drug. The first injection of ketamine was a noteworthy event since it introduced a novel drug or new mode of administration to be further explored by some, or exposed others to a drug to be avoided in the future. Risk reduction messages directed towards young IDUs should be expanded to include ketamine. PMID:16979848

Ketamine for Pain Management-Side Effects & Potential Adverse Events.

PubMed

Allen, Cheryl A; Ivester, Julius R

2017-12-01

An old anesthetic agent, ketamine is finding new use in lower doses for analgesic purposes. There are concerns stemming from its potential side effects-specifically psychomimetic effects. These side effects are directly related to dose amount. The doses used for analgesic purposes are much lower than those used for anesthesia purposes. A literature review was performed to ascertain potential side effects and/or adverse events when using ketamine for analgesia purposes. The search included CINAHL, PubMed, and Ovid using the search terms "ketamine," "ketamine infusion," "pain," "adverse events," "practice guideline," and "randomized controlled trial." Searches were limited to full-text, peer-reviewed articles and systematic reviews. Initially 1,068 articles were retrieved. The search was then narrowed by using the Boolean connector AND with various search term combinations. After adjusting for duplication, article titles and abstracts were reviewed, leaving 25 articles for an in-depth analysis. Specific exclusion criteria were then applied. The literature supports the use of ketamine for analgesic purposes, and ketamine offers a nonopioid option for the management of some pain conditions. Because ketamine is still classified as an anesthetic agent, health care institutions should develop their own set of policies and protocols for the administration of ketamine. By using forethought and understanding of the properties of ketamine, appropriate care may be planned to mitigate potential side effects and adverse events so that patients are appropriately cared for and their pain effectively managed. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Ecotoxicological effect of ketamine: Evidence of acute, chronic and photolysis toxicity to Daphnia magna.

PubMed

Li, Shih-Wei; Wang, Yu-Hsiang; Lin, Angela Yu-Chen

2017-09-01

Ketamine has been increasingly used in medicine and has the potential for abuse or illicit use around the world. Ketamine cannot be removed by conventional wastewater treatment plants. Although ketamine and its metabolite norketamine have been detected to a significant degree in effluents and aquatic environments, their ecotoxicity effects in aquatic organisms remain undefined. In this study, we investigated the acute toxicity of ketamine and its metabolite, along with the chronic reproductive toxicity of ketamine (5-100μg/L) to Daphnia magna. Multiple environmental scenarios were also evaluated, including drug mixtures and sunlight irradiation toxicity. Ketamine and norketamine caused acute toxicity to D. magna, with half lethal concentration (LC 50 ) values of 30.93 and 25.35mg/L, respectively, after 48h of exposure. Irradiated solutions of ketamine (20mg/L) significantly increased the mortality of D. magna; pre-irradiation durations up to 2h rapidly increased the death rate to 100%. A new photolysis byproduct (M.W. 241) of norketamine that accumulates during irradiation was identified for the first time. The relevant environmental concentration of ketamine produced significant reproductive toxicity effects in D. magna, as revealed by the reduction of the number of total live offspring by 33.6-49.8% (p < 0.05). The toxicity results indicate that the environmental hazardous risks of the relevant ketamine concentration cannot be ignored and warrant further examination. Copyright © 2017 Elsevier Inc. All rights reserved.

Intravenous Ketamine Infusions for Neuropathic Pain Management: A Promising Therapy in Need of Optimization.

PubMed

Maher, Dermot P; Chen, Lucy; Mao, Jianren

2017-02-01

Intravenous ketamine infusions have been used extensively to treat often-intractable neuropathic pain conditions. Because there are many widely divergent ketamine infusion protocols described in the literature, the variation in these protocols presents a challenge for direct comparison of one protocol with another and in discerning an optimal protocol. Careful examination of the published literature suggests that ketamine infusions can be useful to treat neuropathic pain and that certain characteristics of ketamine infusions may be associated with better clinical outcomes. Increased duration of relief from neuropathic pain is associated with (1) higher total infused doses of ketamine; (2) prolonged infusion durations, although the rate of infusion does not appear to be a factor; and (3) coadministration of adjunct medications such as midazolam and/or clonidine that mitigate some of the unpleasant psychomimetic side effects. However, there are few studies designed to optimize ketamine infusion protocols by defining what an effective infusion protocol entails with regard to a respective neuropathic pain condition. Therefore, despite common clinical practice, the current state of the literature leaves the use of ketamine infusions without meaningful guidance from high-quality comparative evidence. The objectives of this topical review are to (1) analyze the available clinical evidence related to ketamine infusion protocols and (2) call for clinical studies to identify optimal ketamine infusion protocols tailored for individual neuropathic pain conditions. The Oxford Center for Evidence-Based Medicine classification for levels of evidence was used to stratify the grades of clinical recommendation for each infusion variable studied.

Mutual enhancement of central neurotoxicity induced by ketamine followed by methamphetamine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ke, J.-J.; Chen, H.-I.; Jen, C.J.

2008-03-01

We hereby report that repeated administration of ketamine (350 mg/kg in total) and methamphetamine (30 mg/kg in total) causes specific glutamatergic and dopaminergic neuron deficits, respectively, in adult mouse brain. Acute ketamine did not affect basal body temperature or the later methamphetamine-induced hyperthermia. However, pretreatment with repeated doses of ketamine aggravated methamphetamine-induced dopaminergic terminal loss as evidenced by a drastic decrease in the levels of dopamine, 3,4-dihydroxyphenylacetic acid, and dopamine transporter density as well as poor gait balance performance. In contrast, methamphetamine-induced serotonergic depletion was not altered by ketamine pretreatment. Likewise, the subsequent treatment with methamphetamine exacerbated the ketamine-induced glutamatergicmore » damage as indicated by reduced levels of the vesicular glutamate transporter in hippocampus and striatum and poor memory performance in the Morris water maze. Finally, since activation of the D1 and AMPA/kainate receptors has been known to be involved in the release of glutamate and dopamine, we examined the effects of co-administration of SCH23390, a D1 antagonist, and CNQX, an AMPA/kainate antagonist. Intraventricular CNQX infusion abolished ketamine's potentiation of methamphetamine-induced dopamine neurotoxicity, while systemic SCH23390 mitigated methamphetamine's potentiation of ketamine-induced glutamatergic toxicity. We conclude that repeated doses of ketamine potentiate methamphetamine-induced dopamine neurotoxicity via AMPA/kainate activation and that conjunctive use of methamphetamine aggravates ketamine-induced glutamatergic neurotoxicity possibly via D1 receptor activation.« less

Ketamine versus Ketamine / magnesium Sulfate for Procedural Sedation and Analgesia in the Emergency Department: A Randomized Clinical Trial

PubMed Central

Azizkhani, Reza; Bahadori, Azadeh; Shariati, Mohammadreza; Golshani, Keyhan; Ahmadi, Omid; Masoumi, Babak

2018-01-01

Background: The present study was designed to evaluate the effectiveness of magnesium sulfate (MgSO4) in procedural sedation and analgesia (PSA) when combined with ketamine in patients with fractures in emergency departments and required short and painful emergency procedures. Materials and Methods: In this study, 100 patients with fractures and dislocations who were presented to the emergency departments and required PSA for short and painful emergency procedures were randomly allocated to groups of ketamine plus MgSO4 or ketamine alone. Train of four (TOF) stimulation pattern was assessed using nerve stimulator machine and compared between groups. Results: The mean age of studied patients was 46.9 ± 9.3 years old. 48% were male and 52% were female. No significant differences were noted between groups in demographic variables. The status of TOF, 2 min after the injection of ketamine (1.5 mg/kg), in both groups was similar. After the injection of the second dose of ketamine (1 mg/kg) the status of TOF in four patients in ketamine plus MgSO4 (0.45 mg/kg) group changed, it was three quarters but in ketamine group, the status of TOF in all patients was four quarters. The difference between groups was not statistically significant (P = 0.12). Conclusion: The findings revealed that for muscle relaxation during medical procedures in the emergency department, ketamine in combination with MgSO4 with this dose was not effective for muscle relaxation during procedures. PMID:29456990

Ketamine versus Ketamine / magnesium Sulfate for Procedural Sedation and Analgesia in the Emergency Department: A Randomized Clinical Trial.

PubMed

Azizkhani, Reza; Bahadori, Azadeh; Shariati, Mohammadreza; Golshani, Keyhan; Ahmadi, Omid; Masoumi, Babak

2018-01-01

The present study was designed to evaluate the effectiveness of magnesium sulfate (MgSO 4 ) in procedural sedation and analgesia (PSA) when combined with ketamine in patients with fractures in emergency departments and required short and painful emergency procedures. In this study, 100 patients with fractures and dislocations who were presented to the emergency departments and required PSA for short and painful emergency procedures were randomly allocated to groups of ketamine plus MgSO 4 or ketamine alone. Train of four (TOF) stimulation pattern was assessed using nerve stimulator machine and compared between groups. The mean age of studied patients was 46.9 ± 9.3 years old. 48% were male and 52% were female. No significant differences were noted between groups in demographic variables. The status of TOF, 2 min after the injection of ketamine (1.5 mg/kg), in both groups was similar. After the injection of the second dose of ketamine (1 mg/kg) the status of TOF in four patients in ketamine plus MgSO 4 (0.45 mg/kg) group changed, it was three quarters but in ketamine group, the status of TOF in all patients was four quarters. The difference between groups was not statistically significant ( P = 0.12). The findings revealed that for muscle relaxation during medical procedures in the emergency department, ketamine in combination with MgSO 4 with this dose was not effective for muscle relaxation during procedures.

PACAP Protects Adult Neural Stem Cells from the Neurotoxic Effect of Ketamine Associated with Decreased Apoptosis, ER Stress and mTOR Pathway Activation

PubMed Central

Mansouri, Shiva; Agartz, Ingrid; Ögren, Sven-Ove; Patrone, Cesare; Lundberg, Mathias

2017-01-01

Ketamine administration is a well-established approach to mimic experimentally some aspects of schizophrenia. Adult neurogenesis dysregulation is associated with psychiatric disorders, including schizophrenia. The potential role of neurogenesis in the ketamine-induced phenotype is largely unknown. Recent results from human genetic studies have shown the pituitary adenylate cyclase-activating polypeptide (PACAP) gene is a risk factor for schizophrenia. Its potential role on the regulation of neurogenesis in experimental model of schizophrenia remains to be investigated. We aimed to determine whether ketamine affects the viability of adult neural stem cells (NSC). We also investigated whether the detrimental effect mediated by ketamine could be counteracted by PACAP. NSCs were isolated from the subventricular zone of the mouse and exposed to ketamine with/without PACAP. After 24 hours, cell viability, potential involvement of apoptosis, endoplasmic reticulum (ER) stress, mTOR and AMPA pathway activation were assessed by quantitative RT-PCR and Western blot analysis. We show that ketamine impairs NSC viability in correlation with increased apoptosis, ER stress and mTOR activation. The results also suggest that the effect of ketamine occurs via AMPA receptor activation. Finally, we show that PACAP counteracted the decreased NSC viability induced by ketamine via the specific activation of the PAC-1 receptor subtype. Our study shows that the NSC viability may be negatively affected by ketamine with putative importance for the development of a schizophrenia phenotype in the ketamine induced animal model of schizophrenia. The neuroprotective effect via PAC-1 activation suggests a potentially novel pharmacological target for the treatment of schizophrenia, via neurogenesis normalization. PMID:28125634

Left ventricular, systemic arterial, and baroreflex responses to ketamine and TEE in chronically instrumented monkeys

NASA Technical Reports Server (NTRS)

Koenig, S. C.; Ludwig, D. A.; Reister, C.; Fanton, J. W.; Ewert, D.; Convertino, V. A.

2001-01-01

Effects of prescribed doses of ketamine five minutes after application and influences of transesophageal echocardiography (TEE) on left ventricular, systemic arterial, and baroreflex responses were investigated to test the hypothesis that ketamine and/or TEE probe insertion alter cardiovascular function. Seven rhesus monkeys were tested under each of four randomly selected experimental conditions: (1) intravenous bolus dose of ketamine (0.5 ml), (2) continuous infusion of ketamine (500 mg/kg/min), (3) continuous infusion of ketamine (500 mg/kg/min) with TEE, and (4) control (no ketamine or TEE). Monkeys were chronically instrumented with a high fidelity, dual-sensor micromanometer to measure left ventricular and aortic pressure and a transit-time ultrasound probe to measure aortic flow. These measures were used to calculate left ventricular function. A 4-element Windkessel lumped-parameter model was used to estimate total peripheral resistance and systemic arterial compliance. Baroreflex response was calculated as the change in R-R interval divided by the change in mean aortic pressure measured during administration of graded concentrations of nitroprusside. The results indicated that five minutes after ketamine application heart rate and left ventricular diastolic compliance decreased while TEE increased aortic systolic and diastolic pressure. We conclude that ketamine may be administered as either a bolus or continuous infusion without affecting cardiovascular function 5 minutes after application while the insertion of a TEE probe will increase aortic pressure. The results for both ketamine and TEE illustrate the classic "Hawthorne Effect," where the observed values are partly a function of the measurement process. Measures of aortic pressure, heart rate, and left ventricular diastolic pressure should be viewed as relative, as opposed to absolute, when organisms are sedated with ketamine or instrumented with a TEE probe.

Ketamine potentiates oxidative stress and influences behavior and inflammation in response to lipolysaccharide (LPS) exposure in early life.

PubMed

Réus, Gislaine Z; Simões, Lutiana R; Colpo, Gabriela D; Scaini, Giselli; Oses, Jean P; Generoso, Jaqueline S; Prossin, Alan R; Kaddurah-Daouk, Rima; Quevedo, João; Barichello, Tatiana

2017-06-14

Immune activation (IA) during the early neonatal period is a risk factor for the development of schizophrenia. Lipopolysaccharide (LPS) injected in neonates lead to behavioral and brain changes that persist to adult life. We investigated oxidative stress, levels of cytokines, and the locomotor activity of IA in a schizophrenia animal model in which neonatal male Wistar rats were administered with an injection of LPS (50μg/kg) on postnatal day 3 and different doses of ketamine (5, 15 and 25mg/kg) for 7days during adulthood. Rats LPS-induced did not have locomotor activity alterations. Locomotor activity was elevated in neonatally saline-injected in the higher dose ketamine-treated animals. Carbonyl protein in the prefrontal cortex (PFC), hippocampus and striatum were increased in the LPS- and saline-induced in the ketamine (25mg/kg)-treated animals. Lipid damage occurred in the PFC, striatum and hippocampus in the LPS- and saline-induced in the ketamine (15 and 25mg/kg) -treated animals. In the hippocampus the superoxide dismutase (SOD) was decreased in the LPS- and saline-induced in the ketamine-treated with the dose of 25mg/kg. In the PFC SOD was reduced in the LPS-induced in the ketamine (25mg/kg)-treated animals. Catalase in the PFC and hippocampus was reduced in the LPS- and saline-induced in the ketamine (25mg/kg)-treated animals. Pro- and anti-inflammatory cytokines were lower in the brains of LPS-induced in the higher dose ketamine-treated rats. IA influences the locomotor activity and cytokine levels induced by ketamine, and it has a negative effect in potentiating the oxidative stress by higher doses of ketamine in the brain. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Ketamine Causes Mitochondrial Dysfunction in Human Induced Pluripotent Stem Cell-Derived Neurons

PubMed Central

Ito, Hiroyuki; Uchida, Tokujiro; Makita, Koshi

2015-01-01

Purpose Ketamine toxicity has been demonstrated in nonhuman mammalian neurons. To study the toxic effect of ketamine on human neurons, an experimental model of cultured neurons from human induced pluripotent stem cells (iPSCs) was examined, and the mechanism of its toxicity was investigated. Methods Human iPSC-derived dopaminergic neurons were treated with 0, 20, 100 or 500 μM ketamine for 6 and 24 h. Ketamine toxicity was evaluated by quantification of caspase 3/7 activity, reactive oxygen species (ROS) production, mitochondrial membrane potential, ATP concentration, neurotransmitter reuptake activity and NADH/NAD+ ratio. Mitochondrial morphological change was analyzed by transmission electron microscopy and confocal microscopy. Results Twenty-four-hour exposure of iPSC-derived neurons to 500 μM ketamine resulted in a 40% increase in caspase 3/7 activity (P < 0.01), 14% increase in ROS production (P < 0.01), and 81% reduction in mitochondrial membrane potential (P < 0.01), compared with untreated cells. Lower concentration of ketamine (100 μM) decreased the ATP level (22%, P < 0.01) and increased the NADH/NAD+ ratio (46%, P < 0.05) without caspase activation. Transmission electron microscopy showed enhanced mitochondrial fission and autophagocytosis at the 100 μM ketamine concentration, which suggests that mitochondrial dysfunction preceded ROS generation and caspase activation. Conclusions We established an in vitro model for assessing the neurotoxicity of ketamine in iPSC-derived neurons. The present data indicate that the initial mitochondrial dysfunction and autophagy may be related to its inhibitory effect on the mitochondrial electron transport system, which underlies ketamine-induced neural toxicity. Higher ketamine concentration can induce ROS generation and apoptosis in human neurons. PMID:26020236

Ketamine Corrects Stress-Induced Cognitive Dysfunction through JAK2/STAT3 Signaling in the Orbitofrontal Cortex

PubMed Central

Patton, Michael S; Lodge, Daniel J; Morilak, David A; Girotti, Milena

2017-01-01

Deficits in cognitive flexibility are prominent in stress-related psychiatric disorders, including depression. Ketamine has rapid antidepressant efficacy, but it is unknown if ketamine improves cognitive symptoms. In rats, 2 weeks chronic intermittent cold (CIC) stress impairs reversal learning, a form of cognitive flexibility mediated by the orbitofrontal cortex (OFC) that we have used previously to model cognitive dysfunction in depression. We have shown that activating JAK2/STAT3 signaling in the OFC rescued the CIC stress-induced reversal learning deficit. Thus, in the present study we determined whether ketamine also corrects the stress-induced reversal learning deficit, and if JAK2/STAT3 signaling is involved in this effect. A single injection of ketamine (10 mg/kg, i.p.) 24 h prior to testing rescued the CIC stress-induced reversal learning deficit. CIC stress decreased JAK2 phosphorylation in the OFC, and ketamine restored pJAK2 levels within 2 h post injection. The JAK2 inhibitor AG490 given systemically or into the OFC at the time of ketamine injection prevented its beneficial effect on reversal learning. We then tested the role of JAK2/STAT3 in ketamine-induced plasticity in the OFC. Ketamine depressed local field potentials evoked in the OFC by excitatory thalamic afferent stimulation, and this was prevented by JAK2 inhibition in the OFC. Further, in both the OFC and primary cortical neurons in culture, ketamine increased expression of the neural plasticity-related protein Arc, and this was prevented by JAK2 inhibition. These results suggest that the JAK2/STAT3 signaling pathway is a novel mechanism by which ketamine exerts its therapeutic effects on stress-induced cognitive dysfunction in the OFC. PMID:27748739

Effective and Safe Anesthesia for Yorkshire and Yucatan Swine with and without Cardiovascular Injury and Intervention

PubMed Central

Linkenhoker, Jan R; Burkholder, Tanya H; Linton, CG Garry; Walden, April; Abusakran-Monday, Kim A; Rosero, Ana P; Foltz, Charmaine J

2010-01-01

The goal of this study was to identify an injectable anesthetic protocol that provides sedation sufficient for peripheral vascular catheterization, intubation, and transport while minimizing cardiovascular changes in Yorkshire and Yucatan pigs with and without cardiovascular injury and intervention (CI). Phase 1 examined the safety and efficacy of acepromazine–ketamine, diazepam–ketamine, midazolam–ketamine, and medetomidine–ketamine in 5 healthy Yorkshire pigs. For each drug combination, we obtained multiple measurements of heart rate, blood pressure, respiratory rate, temperature, sedation score, ability to catheterize and intubate, and recovery score. Phase 2 evaluated and refined the dose of the most effective Phase 1 anesthetic combination (midazolam–ketamine) in healthy and CI Yorkshire pigs (n = 53 trials). Phase 3 mirrored Phase 2 but tested midazolam–ketamine in healthy and CI Yucatan pigs (n = 34 trials). Midazolam (0.5 mg/kg)–ketamine (25 to 27 mg/kg) was the most effective anesthetic combination in healthy Yorkshire pigs, but this dose was less effective in healthy Yucatan pigs and CI Yorkshire and Yucatan pigs. Midazolam–ketamine resulted in tachycardia and apnea more frequently in CI pigs than healthy pigs. This combination also caused vomiting in one CI Yucatan pig. Overall, midazolam–ketamine provided safe and effective sedation for catheterization and intubation of both healthy and CI pigs. This study suggests Yucatan pigs may require a higher dose midazolam–ketamine to achieve the same level of sedation as that in Yorkshire pigs. Although anesthetic complication rates were higher in CI pigs, our results indicate that midazolam–ketamine can be safely used for sedation of both pig breeds with and without CI. PMID:20587167

Ketamine induces toxicity in human neurons differentiated from embryonic stem cells via mitochondrial apoptosis pathway

PubMed Central

Bosnjak, Zeljko J.; Yan, Yasheng; Canfield, Scott; Muravyeva, Maria Y.; Kikuchi, Chika; Wells, Clive; Corbett, John; Bai, Xiaowen

2013-01-01

Ketamine is widely used for anesthesia in pediatric patients. Growing evidence indicates that ketamine causes neurotoxicity in a variety of developing animal models. Our understanding of anesthesia neurotoxicity in humans is currently limited by difficulties in obtaining neurons and performing developmental toxicity studies in fetal and pediatric populations. It may be possible to overcome these challenges by obtaining neurons from human embryonic stem cells (hESCs) in vitro. hESCs are able to replicate indefinitely and differentiate into every cell type. In this study, we investigated the toxic effect of ketamine on neurons differentiated from hESCs. Two-week-old neurons were treated with different doses and durations of ketamine with or without the reactive oxygen species (ROS) scavenger, Trolox. Cell viability, ultrastructure, mitochondrial membrane potential (ΔΨm), cytochrome c distribution within cells, apoptosis, and ROS production were evaluated. Here we show that ketamine induced ultrastructural abnormalities and dose- and time-dependently caused cell death. In addition, ketamine decreased ΔΨm and increased cytochrome c release from mitochondria. Ketamine also increased ROS production and induced differential expression of oxidative stress-related genes. Specifically, abnormal ultrastructural and ΔΨm changes occurred earlier than cell death in the ketamine-induced toxicity process. Furthermore, Trolox significantly decreased ROS generation and attenuated cell death caused by ketamine in a dose-dependent manner. In conclusion, this study illustrates that ketamine time- and dose-dependently induces human neurotoxicity via ROS-mediated mitochondrial apoptosis pathway and that these side effects can be prevented by the antioxidant agent Trolox. Thus, hESC-derived neurons might provide a promising tool for studying anesthetic-induced developmental neurotoxicity and prevention strategies. PMID:22873495

Protective effect of ketamine against hemorrhagic cystitis in rats receiving ifosfamide

PubMed Central

Ozguven, Ali A.; Yılmaz, Omer; Taneli, Fatma; Ulman, Cevval; Vatansever, Seda; Onag, Ali

2014-01-01

Objective: To investigate the possible protective effect of a single dose of ketamine and the synergistic effect between ketamine and 2-mercaptoethane sulfonate (mesna) against ifosfamide-induced hemorrhagic cystitis. Materials and Methods: 35 adult female wistar rats were divided into five groups and pretreated with ketamine at 10 mg/kg and/or mesna 400 mg/kg 30 minutes before intraperitoneal injection of IFS (400 mg/kg) or with saline (control group). Hemorrhagic cystitis was evaluated 24 hours after IFS injection according to bladder wet weight (BWW), and microscopic changes, i.e. edema, hemorrhage, cellular infiltration, and urothelial desquamation. The markers of oxidative damage including nitric oxide (NO) and malondialdehyde (MDA) levels and the expressions of tumor necrosis factor alpha (TNF-α), interleukin 1-beta (IL-1β), inducible nitric oxide synthase (i-NOS) and endothelial nitric oxide synthase (e-NOS) were also assayed in the bladder tissues. Results: Pretreatment with ketamine alone or ketamine in combination with mesna reduced the IFS-induced increase of BWW (58,47% and 63,33%, respectively, P < 0.05). IFS- induced microscopic alterations were also prevented by ketamine with or without mesna (P < 0.05). In addition, also statistically insignificant, the bladder tissue expressions of IL-1β were lower in ketamine and/or mesna-receiving groups (P > 0,05). The parameters of oxidative stress, the NO and the MDA contents of the bladder tissues of the study groups were not different. Conclusion: The results of the present study suggest that a single dose of ketamine pretreatment attenuates experimental IFS-induced bladder damage. It is therefore necessary to investigate ketamine locally and systematically with various dosing schedulesin order to reduce the bladder damage secondary to oxazaphosphorine-alkylating agents and these results may widen the spectrum of ketamine. PMID:24741183

Riluzole for relapse prevention following intravenous ketamine in treatment-resistant depression: a pilot randomized, placebo-controlled continuation trial

PubMed Central

Mathew, Sanjay J.; Murrough, James W.; Rot, Marije aan het; Collins, Katherine A.; Reich, David L.; Charney, Dennis S.

2013-01-01

The N-methyl-d-aspartate (NMDA) glutamate receptor antagonist ketamine may have rapid, albeit transient, antidepressant properties. This study in patients with treatment-resistant major depression (TRD) aimed to (1) replicate the acute efficacy of single-dose intravenous (i.v.) ketamine; (2) test the efficacy of the glutamate-modulating agent riluzole in preventing post-ketamine relapse ; and (3) examine whether pretreatment with lamotrigine would attenuate ketamine’s psychotomimetic effects and enhance its antidepressant activity. Twenty-six medication-free patients received open-label i.v. ketamine (0.5 mg/kg over 40 min). Two hours prior to infusion, patients were randomized to lamotrigine (300 mg) or placebo. Seventeen patients (65%) met response criterion (≥50% reduction from baseline on the Montgomery–Asberg Depression Rating Scale) 24 h following ketamine. Lamotrigine failed to attenuate the mild, transient side-effects associated with ketamine and did not enhance its antidepressant effects. Fourteen patients (54%) met response criterion 72 h following ketamine and proceeded to participate in a 32-d, randomized, double-blind, placebo-controlled, flexible-dose continuation trial of riluzole (100–200 mg/d). The main outcome measure was time-to-relapse. An interim analysis found no significant differences in time-to-relapse between riluzole and placebo groups [log-rank χ2 = 0.17, d.f. = 1, p = 0.68], with 80% of patients relapsing on riluzole vs. 50% on placebo. The trial was thus stopped for futility. This pilot study showed that a sub-anaesthetic dose of i.v. ketamine is well-tolerated in TRD, and may have rapid and sustained antidepressant properties. Riluzole did not prevent relapse in the first month following ketamine. Further investigation of relapse prevention strategies post-ketamine is necessary. PMID:19288975

A prospective study of ketamine versus haloperidol for severe prehospital agitation.

PubMed

Cole, Jon B; Moore, Johanna C; Nystrom, Paul C; Orozco, Benjamin S; Stellpflug, Samuel J; Kornas, Rebecca L; Fryza, Brandon J; Steinberg, Lila W; O'Brien-Lambert, Alex; Bache-Wiig, Peter; Engebretsen, Kristin M; Ho, Jeffrey D

2016-08-01

Ketamine is an emerging drug for the treatment of acute undifferentiated agitation in the prehospital environment, however no prospective comparative studies have evaluated its effectiveness or safety in this clinical setting. We hypothesized 5 mg/kg of intramuscular ketamine would be superior to 10 mg of intramuscular haloperidol for severe prehospital agitation, with time to adequate sedation as the primary outcome measure. This was a prospective open label study of all patients in an urban EMS system requiring chemical sedation for severe acute undifferentiated agitation that were subsequently transported to the EMS system's primary Emergency Department. All paramedics were trained in the Altered Mental Status Scale and prospectively recorded agitation scores on all patients. Two 6-month periods where either ketamine or haloperidol was the first-line therapy for severe agitation were prospectively compared primarily for time to adequate sedation. Secondary outcomes included laboratory data and adverse medication events. 146 subjects were enrolled; 64 received ketamine, 82 received haloperidol. Median time to adequate sedation for the ketamine group was 5 minutes (range 0.4-23) vs. 17 minutes (range 2-84) in the haloperidol group (difference 12 minutes, 95% CI 9-15). Complications occurred in 49% (27/55) of patients receiving ketamine vs. 5% (4/82) in the haloperidol group. Complications specific to the ketamine group included hypersalivation (21/56, 38%), emergence reaction (5/52, 10%), vomiting (5/57, 9%), and laryngospasm (3/55, 5%). Intubation was also significantly higher in the ketamine group; 39% of patients receiving ketamine were intubated vs. 4% of patients receiving haloperidol. Ketamine is superior to haloperidol in terms of time to adequate sedation for severe prehospital acute undifferentiated agitation, but is associated with more complications and a higher intubation rate.

Mood and neuropsychological effects of different doses of ketamine in electroconvulsive therapy for treatment-resistant depression.

PubMed

Zhong, Xiaomei; He, Hongbo; Zhang, Chunping; Wang, Zhijie; Jiang, Miaoling; Li, Qirong; Zhang, Minling; Huang, Xiong

2016-09-01

Treatment-resistant depression (TRD) is a growing clinical challenge. Electroconvulsive therapy (ECT) is an effective tool for TRD treatment. However, there remains a subset of patients who do not respond to this treatment with common anesthetic agent. Ketamine, a noteworthy anesthetic agent, has emerged as an augmentation to enhance the antidepressant efficacy of ECT. Trials of i.v. ketamine in TRD indicated dose-related mood enhancing efficacy. We aimed to explore anesthetic and subanesthetic concentrations of ketamine in ECT for TRD with respect to their impact on mood and neuropsychological effects. Ninety TRD patients (36 males, 54 females; average age, 30.6 years old) were randomly assigned to receive either ketamine (0.8mg/kg) (n=30), subanesthetic ketamine (0.5mg/kg) plus propofol (0.5mg/kg) (n=30) or propofol (0.8mg/kg) (n=30) as an anesthetic and underwent 8 ECT sessions. The primary outcome measures were the 17-item Hamilton Depression Rating Scale (HDRS-17), cognitive assessments and seizure parameters. The ketamine group had an earlier improvement in HDRS-17, longer seizure duration, lower electric quantity, a higher remission rate, and a lower degree of executive cognitive impairment compared to the ketamine+propofol and propofol groups. The ketamine+propofol group showed earlier improvement in the HDRS-17, a longer seizure duration and a different seizure energy index when compared to the propofol group. The postoperative dissociative side effect was not assessed. Both anesthetic and subanesthetic concentrations of ketamine have rapid mood enhancing actions in ECT for TRD, while anesthetic concentrations results in larger magnitudes of antidepression and cognitive protection. ECT with ketamine anesthesia might be an optimized therapy for patients with TRD. Copyright © 2016 Elsevier B.V. All rights reserved.

Dissociable effects of the noncompetitive NMDA receptor antagonists ketamine and MK-801 on intracranial self-stimulation in rats

PubMed Central

Hillhouse, Todd M.; Porter, Joseph H.; Negus, S. Stevens

2014-01-01

Rationale The noncompetitive NMDA antagonist ketamine produces rapid antidepressant effects in treatment-resistant patients suffering from major depressive and bipolar disorders. However, abuse liability is a concern. Objectives This study examined abuse-related effects of keta-mine using intracranial self-stimulation (ICSS) in rats. The higher-affinity NMDA antagonist MK-801 and the monoamine reuptake inhibitor cocaine were examined for comparison. Methods Male Sprague Dawley rats were implanted with electrodes targeting the medial forebrain bundle and trained to respond to brain stimulation under a frequency–rate ICSS procedure. The first experiment compared the potency and time course of ketamine (3.2–10.0 mg/kg) and MK-801 (0.032–0.32 mg/kg). The second experiment examined effects of repeated dosing with ketamine (3.2–20.0 mg/kg/day) and acute cocaine (10.0 mg/kg). Results Following acute administration, ketamine (3.2–10 mg/kg) produced only dose- and time-dependent depressions of ICSS and failed to produce an abuse-related facilitation of ICSS at any dose or pretreatment time. In contrast, MK-801 (0.032–0.32 mg/kg) produced a mixed profile of rate-increasing and rate-decreasing effects; ICSS facilitation was especially prominent at an intermediate dose of 0.18 mg/kg. Repeated dosing with ketamine produced dose-dependent tolerance to the rate-decreasing effects of ketamine (10.0 and 18.0 mg/kg) but failed to unmask expression of ICSS facilitation. Termination of ketamine treatment failed to produce withdrawal-associated decreases in ICSS. As reported previously, 10.0 mg/kg cocaine facilitated ICSS. Conclusions The dissociable effects of ketamine and MK-801 suggest differences in the pharmacology of these nominally similar NMDA antagonists. Failure of ketamine to facilitate ICSS contrasts with other evidence for the abuse liability of ketamine. PMID:24522331

Dose-response characteristics of intravenous ketamine on dissociative stereotypy, locomotion, sensorimotor gating, and nociception in male Sprague-Dawley rats.

PubMed

Radford, Kennett D; Park, Thomas Y; Lee, Bong Hyo; Moran, Sean; Osborne, Lisa A; Choi, Kwang H

2017-02-01

Clinicians administer subanesthetic intravenous (IV) ketamine infusions for treatment of refractory depression, chronic pain, and post-traumatic stress disorder in humans. However, ketamine is administered via the subcutaneous (SC) or intraperitoneal (IP) routes to rodents in most pre-clinical research, which may limit translational application. The present study characterized the dose-response of a subanesthetic IV ketamine bolus (2 and 5mg/kg) and 1-h infusion (5, 10, and 20mg/kg/h) on dissociative stereotypy, locomotion, sensorimotor gating, and thermal nociception in male Sprague-Dawley rats. The secondary aim was to measure ketamine and norketamine plasma concentrations following IV ketamine bolus at 1, 20, and 50min and at the conclusion of the 1-h infusion using liquid chromatography/mass spectrometry. The results showed that ketamine bolus and infusions produced dose-dependent dissociative stereotypy. Bolus (2 and 5mg/kg) and 20mg/kg/h infusion increased locomotor activity while 5mg/kg/h infusion decreased locomotor activity. Both 10 and 20mg/kg/h infusions reduced the acoustic startle reflex, while 5mg/kg bolus and 20mg/kg/h infusion impaired pre-pulse inhibition. Ketamine 5mg/kg bolus and the 10 and 20mg/kg/h infusions induced significant and prolonged antinociception to the hotplate test. Plasma concentrations of ketamine decreased quickly after bolus while norketamine levels increased from 1 to 20min and plateaued from 20 to 50min. The peak ketamine plasma concentrations [ng/ml] were similar between 5mg/kg bolus [4100] vs. 20mg/kg/h infusion [3900], and 2mg/kg bolus [1700] vs. 10mg/kg/h infusion [1500]. These results support the findings from previous ketamine injection studies and further validate the feasibility of administering subanesthetic doses of IV ketamine infusion to rats for neuropharmacological studies. Published by Elsevier Inc.

Case report: efficacy and tolerability of ketamine in opioid-refractory cancer pain.

PubMed

Amin, Priya; Roeland, Eric; Atayee, Rabia

2014-09-01

A 36-year-old female with metastatic breast cancer involving bones, liver, lung, and pleura/chest wall with worsening back pain received weight-based intravenous (IV) ketamine and was transitioned to oral ketamine for cancer-related neuropathic pain. She had responded poorly to outpatient pain regimen of oxycodone sustained and immediate release, hydromorphone, gabapentin, and duloxetine (approximate 480 mg total oral morphine equivalents [OME]), reporting an initial pain score of 10/10. She was started on hydromorphone parenteral patient-controlled analgesia (PCA) bolus dose in addition to her outpatient regimen. Despite escalating doses of opioids and the addition of a lidocaine 5% patch, the patient's pain remained uncontrolled 6 days after admission. On hospital day 7, utilizing a hospital weight-based ketamine protocol, the patient was started on subanesthetic doses of ketamine at 0.2 mg/kg/h (288 mg/24 h) and titrated over 2 days to 0.4 mg/kg/h (576 mg/24 h). Then, a 3-day rotation from intravenous to oral ketamine was initiated, and the patient was discharged on ketamine oral solution, 75 mg every 8 hours. When the patient's dose was increased to 0.4 mg/kg/h, adequate pain relief was charted by the nurse within 120 minutes, "patient pain free and resting comfortably." Her pain continued to be well managed, with an average pain score of 5/10 with the ketamine continuous infusion and sustained with conversion to oral ketamine without any report of side effects. This was a 37% reduction in pain scores. With the patient's stabilized dose of ketamine, opioid requirements decreased by 61.4% (1017.5 mg reduction in total OME). The use of weight-based dosing of IV continuous infusion and transition to oral ketamine was effective and tolerable in the management of opioid-refractory, neuropathic cancer pain. It is hoped that this case report promotes a discussion regarding ketamine dosing in refractory neuropathic cancer pain.

Short- and long-term antidepressant effects of ketamine in a rat chronic unpredictable stress model.

PubMed

Jiang, Yinghong; Wang, Yiqiang; Sun, Xiaoran; Lian, Bo; Sun, Hongwei; Wang, Gang; Du, Zhongde; Li, Qi; Sun, Lin

2017-08-01

This research was aimed to evaluate the behaviors of short- or long-term antidepressant effects of ketamine in rats exposed to chronic unpredictable stress (CUS). Ketamine, a glutamate noncompetitive NMDA receptor antagonist, regulates excitatory amino acid functions, such as anxiety disorders and major depression, and plays an important role in synaptic plasticity and learning and memory. After 42 days of CUS model, male rats received either a single injection of ketamine (10 mg/kg; day 43) or 15 daily injections (days 43-75). The influence of ketamine on behavioral reactivity was assessed 24 hr (short-term) or 7 weeks after ketamine treatment (long-term). Behavioral tests used to assess the effects of these treatments included the sucrose preference (SP), open field (OF), elevated plus maze (EPM), forced swimming (FS), and water maze (WM) to detect anxiety-like behavior (OF and EPM), forced swimming (FS), and water maze (WM). Results: Short-term ketamine administration resulted in increases of body weight gain, higher sensitivity to sucrose, augmented locomotor activity in the OF, more entries into the open arms of the EPM, along increased activity in the FS test; all responses indicative of reductions in depression/despair in anxiety-eliciting situations. No significant differences in these behaviors were obtained under conditions of long-term ketamine administration ( p  > .05). The CUS + Ketamine group showed significantly increased activity as compared with the CUS + Vehicle group for analysis of the long-term effects of ketamine (* p  < .05). Nor were significant differences obtained in learning and memory performance in rats receiving ketamine ( p  > .05). Taken together these findings demonstrate that a short-term administration of ketamine induced rapid antidepressant-like effects in adult male rats exposed to CUS conditions, effects that were not observed in response to the long-term treatment regime.

The Use of Prehospital Ketamine for Control of Agitation in a Metropolitan Firefighter-based EMS System.

PubMed

Keseg, David; Cortez, Eric; Rund, Douglas; Caterino, Jeffrey

2015-01-01

Abstract Introduction. Prehospital personnel frequently encounter agitated, combative, and intoxicated patients in the field. In recent years, ketamine has been described as an effective sedative agent to treat such patients; however, a paucity of research exists describing the use of prehospital ketamine. The objective of this study was to provide a descriptive analysis of the Columbus Division of Fire's experience with utilizing ketamine in the prehospital setting. We hypothesized that ketamine administration improves patient condition, is effective at sedating patients, and does not result in endotracheal intubation in the prehospital setting or in the emergency department (ED). Methods. We conducted a retrospective cohort chart review of Columbus Division of Fire patient care reports and hospital records from destination hospitals in the central Ohio region between October 2010 and October 2012. All patients receiving ketamine administered by Columbus Division of Fire personnel for sedation were included. Patients 17 years and younger were excluded. The primary outcome was the percentage of patients noted to have an "improved" condition recorded in the data field of the patient care report. The secondary outcomes were the effectiveness of sedation and the performance of endotracheal intubation. Results. A total of 36 patients met inclusion criteria over the study period. Data were available on 35 patients for analysis. The mean IV dose of ketamine was 138 mg (SD = 59.5, 100-200). The mean IM dose of ketamine was 324 mg (SD = 120, 100-500). Prehospital records noted an improvement in patient condition after ketamine administration in 32 cases (91%, 95% CI 77-98%). Six patients required sedation post-ketamine administration either by EMS (2) or in the ED (4) (17%, 95% CI 6.5-34%). Endotracheal intubation was performed in eight (23%, 95% CI 10-40%) patients post-ketamine administration. Conclusion. We found that in a cohort of patients administered ketamine, paramedics reported a subjective improvement in patient condition. Endotracheal intubation was performed in 8 patients.

Effects of maropitant citrate or acepromazine on the incidence of adverse events associated with hydromorphone premedication in dogs.

PubMed

Claude, A K; Dedeaux, A; Chiavaccini, L; Hinz, S

2014-01-01

Vomiting is a common complication associated with the use of hydromorphine for pre-emptive analgesia in dogs. The ideal anti-emetic protocol for prevention of this complication has not been established. Maropitant administered concurrently or before hydromorphone would reduce the incidence of vomiting, signs of nausea, ptyalism, and increased panting compared to administration of acepromazine or a 0.9% saline control. Sixty mixed-breed female dogs scheduled for ovariohysterectomy. Randomized, blinded, placebo-controlled experimental study. Dogs were assigned to 4 experimental groups with 15 dogs per group. All groups received 0.2 mg/kg of hydromorphone IM. Group "Control" received 0.1 mL/kg saline SC 30-45 minutes before hydromorphone, group "Marop1" received 1 mg/kg maropitant SC 30-45 minutes before hydromorphone, group "Ace" received 0.02 mg/kg IM acepromazine 30-45 minutes before hydromorphone, and group "Marop2" received 1 mg/kg SC maropitant concurrently with hydromorphone. A trained and blinded observer documented adverse events from the time hydromorphone was administered until the time dogs were induced for surgery. Marop1 had significantly less vomiting (0%) compared to Control (87%; P < .01) and Ace (53%; P < .01). Marop2 had significantly less vomiting (27%) compared to Control (P < .01). Marop1 had significantly greater incidence of ptyalism (73%) compared to Ace (P < .01; 20%). Ace showed significantly less panting (33%) compared to Marop2 (93%; P < .01). In healthy dogs, maropitant citrate administered before hydromorphone significantly decreases the incidence of vomiting in dogs but does not improve signs of nausea, ptyalism, or increased panting. Copyright © 2014 by the American College of Veterinary Internal Medicine.

Study protocol for the randomised controlled trial: Ketamine augmentation of ECT to improve outcomes in depression (Ketamine-ECT study).

PubMed

Trevithick, Liam; McAllister-Williams, R Hamish; Blamire, Andrew; Branton, Tim; Clark, Ross; Downey, Darragh; Dunn, Graham; Easton, Andrew; Elliott, Rebecca; Ellwell, Clare; Hayden, Katherine; Holland, Fiona; Karim, Salman; Lowe, Jo; Loo, Colleen; Nair, Rajesh; Oakley, Timothy; Prakash, Antony; Sharma, Parveen K; Williams, Stephen R; Anderson, Ian M

2015-10-21

There is a robust empirical evidence base supporting the acute efficacy of electroconvulsive therapy (ECT) for severe and treatment resistant depression. However, a major limitation, probably contributing to its declining use, is that ECT is associated with impairment in cognition, notably in anterograde and retrograde memory and executive function. Preclinical and preliminary human data suggests that ketamine, used either as the sole anaesthetic agent or in addition to other anaesthetics, may reduce or prevent cognitive impairment following ECT. A putative hypothesis is that ketamine, through antagonising glutamate receptors, protects from excess excitatory neurotransmitter stimulation during ECT. The primary aim of the ketamine-ECT study is to investigate whether adjunctive ketamine can attenuate the cognitive impairment caused by ECT. Its secondary aim is to examine if ketamine increases the speed of clinical improvement with ECT. The ketamine ECT study is a multi-site randomised, placebo-controlled, double blind trial. It was originally planned to recruit 160 moderately to severely depressed patients who had been clinically prescribed ECT. This recruitment target was subsequently revised to 100 patients due to recruitment difficulties. Patients will be randomly allocated on a 1:1 basis to receive either adjunctive ketamine or saline in addition to standard anaesthesia for ECT. The primary neuropsychological outcome measure is anterograde verbal memory (Hopkins Verbal Learning Test-Revised delayed recall task) after 4 ECT treatments. Secondary cognitive outcomes include verbal fluency, autobiographical memory, visuospatial memory and digit span. Efficacy is assessed using observer and self-report efficacy measures of depressive symptomatology. The effects of ECT and ketamine on cortical activity during cognitive tasks will be studied in a sub-sample using functional near-infrared spectroscopy (fNIRS). The ketamine-ECT study aims to establish whether or not adjunctive ketamine used together with standard anaesthesia for ECT will significantly reduce the adverse cognitive effects observed after ECT. Potential efficacy benefits of increased speed of symptom improvement and a reduction in the number of ECT treatments required will also be assessed, as will safety and tolerability of adjunctive ketamine. This study will provide important evidence as to whether adjunctive ketamine is routinely indicated for ECT given for depression in routine NHS clinical practice. Current Controlled Trials: ISRCTN14689382 (assigned 30/07/2012); EudraCT Number: 2011-005476-41.

Topical amitriptyline and ketamine for the treatment of neuropathic pain.

PubMed

Mercadante, Sebastiano

2015-01-01

A neuropathy is a disturbance of function or pathological change in nerves. In some cases, peripheral neuropathic pain may occur due to a lesion or disease of the peripheral somatosensory nervous system. Efficacy of different agents for peripheral neuropathic pain conditions is less than optimal. The administration of topical analgesics might be an option, due to the potential of reduced adverse effects and increased patient compliance. There is major interest in compounding topical analgesics for peripheral neuropathic pain, but several challenges remain for this approach. Topical analgesics have the potential to be a valuable additional approach for the management of peripheral neuropathic pain. Topical amitriptyline-ketamine combination (AK) is a promising agent for peripheral neuropathic pain conditions. Some studies have shown its efficacy in neuropathic pain conditions. However, this data was not uniformely obtained and its role remains still controversial. Efficacy may depend on many factors, including the choice of the vehicle, the concentration, the pain site, and specific diseases. More studies are necessary to support the use of AK in clinical practice.

Ketamine - A Multifaceted Drug.

PubMed

Meng, Lingzhong; Li, Jian; Lu, Yi; Sun, Dajin; Tao, Yuan-Xiang; Liu, Renyu; Luo, Jin Jun

There is a petition for tight control of ketamine from the Chinese government to classify ketamine as a Schedule I drug, which is defined as a drug with no currently accepted medical use but a high potential for abuse. However, ketamine has unique properties that can benefit different patient populations. Scholars from the Translational Perioperative and Pain Medicine and the International Chinese Academy of Anesthesiology WeChat groups had an interactive discussion on ketamine, including its current medical applications, future research priorities, and benefits versus risks. The discussion is summarized in this manuscript with some minor edits.

Intravenous sub-anesthetic ketamine for perioperative analgesia

PubMed Central

Gorlin, Andrew W; Rosenfeld, David M; Ramakrishna, Harish

2016-01-01

Ketamine, an N-methyl-d-aspartate antagonist, blunts central pain sensitization at sub-anesthetic doses (0.3 mg/kg or less) and has been studied extensively as an adjunct for perioperative analgesia. At sub-anesthetic doses, ketamine has a minimal physiologic impact though it is associated with a low incidence of mild psychomimetic symptoms as well as nystagmus and double vision. Contraindications to its use do exist and due to ketamine's metabolism, caution should be exercised in patients with renal or hepatic dysfunction. Sub-anesthetic ketamine improves pain scores and reduces perioperative opioid consumption in a broad range of surgical procedures. In addition, there is evidence that ketamine may be useful in patients with opioid tolerance and for preventing chronic postsurgical pain. PMID:27275042

Recent insights into the mode of action of memantine and ketamine

PubMed Central

Johnson, Jon W.; Glasgow, Nathan G.; Povysheva, Nadezhda V.

2014-01-01

The clinical benefits of the glutamate receptor antagonists memantine and ketamine have helped sustain optimism that glutamate receptors represent viable targets for development of therapeutic drugs. Both memantine and ketamine antagonize N-methyl-d-aspartate receptors (NMDARs), a glutamate receptor subfamily, by blocking the receptor-associated ion channel. Although many of the basic characteristics of NMDAR inhibition by memantine and ketamine appear similar, their effects on humans and to a lesser extent on rodents are strongly divergent. Some recent research suggests that preferential inhibition by memantine and ketamine of distinct NMDAR subpopulations may contribute to the drugs' differential clinical effects. Here we review studies that shed light on possible explanations for differences between the effects of memantine and ketamine. PMID:25462293

A comparison between maropitant and metoclopramide for the prevention of morphine-induced nausea and vomiting in dogs

PubMed Central

Lorenzutti, Augusto M.; Martín-Flores, Manuel; Litterio, Nicolás J.; Himelfarb, Martín A.; Invaldi, Sergio H.; Zarazaga, María P.

2017-01-01

Morphine is widely used as a preanesthetic agent in dogs, but it often produces signs of nausea and vomiting. Maropitant (MRP) and metoclopramide (MCP) prevent emesis attributable to the opioid agent apomorphine in dogs. We evaluated the antiemetic efficacy and the discomfort in response to SQ injection of MRP [1 mg/kg body weight (BW)], MCP (0.5 mg/kg BW), and normal saline (SAL; 0.1 mL/kg BW) administered to 63 dogs, 45 minutes prior to morphine (0.5 mg/kg BW) and acepromazine (0.05 mg/kg BW). Dogs were observed for signs of nausea (ptyalism, lip licking, and increased swallowing) and vomiting for 30 minutes after morphine/acepromazine. The incidence of emesis was 0% for MRP, 38% for MCP, and 71% for SAL (P < 0.001). The incidence of signs of nausea was not different between groups. Discomfort due to injection was higher after MRP (48%), than after MCP (9.8%) and SAL (4.8%) (P < 0.001). PMID:28042152

A comparison between maropitant and metoclopramide for the prevention of morphine-induced nausea and vomiting in dogs.

PubMed

Lorenzutti, Augusto M; Martín-Flores, Manuel; Litterio, Nicolás J; Himelfarb, Martín A; Invaldi, Sergio H; Zarazaga, María P

2017-01-01

Morphine is widely used as a preanesthetic agent in dogs, but it often produces signs of nausea and vomiting. Maropitant (MRP) and metoclopramide (MCP) prevent emesis attributable to the opioid agent apomorphine in dogs. We evaluated the antiemetic efficacy and the discomfort in response to SQ injection of MRP [1 mg/kg body weight (BW)], MCP (0.5 mg/kg BW), and normal saline (SAL; 0.1 mL/kg BW) administered to 63 dogs, 45 minutes prior to morphine (0.5 mg/kg BW) and acepromazine (0.05 mg/kg BW). Dogs were observed for signs of nausea (ptyalism, lip licking, and increased swallowing) and vomiting for 30 minutes after morphine/acepromazine. The incidence of emesis was 0% for MRP, 38% for MCP, and 71% for SAL ( P < 0.001). The incidence of signs of nausea was not different between groups. Discomfort due to injection was higher after MRP (48%), than after MCP (9.8%) and SAL (4.8%) ( P < 0.001).

Ketamine for chronic pain: risks and benefits

PubMed Central

Niesters, Marieke; Martini, Christian; Dahan, Albert

2014-01-01

The anaesthetic ketamine is used to treat various chronic pain syndromes, especially those that have a neuropathic component. Low dose ketamine produces strong analgesia in neuropathic pain states, presumably by inhibition of the N-methyl-D-aspartate receptor although other mechanisms are possibly involved, including enhancement of descending inhibition and anti-inflammatory effects at central sites. Current data on short term infusions indicate that ketamine produces potent analgesia during administration only, while three studies on the effect of prolonged infusion (4–14 days) show long-term analgesic effects up to 3 months following infusion. The side effects of ketamine noted in clinical studies include psychedelic symptoms (hallucinations, memory defects, panic attacks), nausea/vomiting, somnolence, cardiovascular stimulation and, in a minority of patients, hepatoxicity. The recreational use of ketamine is increasing and comes with a variety of additional risks ranging from bladder and renal complications to persistent psychotypical behaviour and memory defects. Blind extrapolation of these risks to clinical patients is difficult because of the variable, high and recurrent exposure to the drug in ketamine abusers and the high frequency of abuse of other illicit substances in this population. In clinical settings, ketamine is well tolerated, especially when benzodiazepines are used to tame the psychotropic side effects. Irrespective, close monitoring of patients receiving ketamine is mandatory, particularly aimed at CNS, haemodynamic, renal and hepatic symptoms as well as abuse. Further research is required to assess whether the benefits outweigh the risks and costs. Until definite proof is obtained ketamine administration should be restricted to patients with therapy-resistant severe neuropathic pain. PMID:23432384

Ketamine accelerates fear extinction via mTORC1 signaling

PubMed Central

Girgenti, Matthew J.; Ghosal, Sriparna; LoPresto, Dora; Taylor, Jane R.; Duman, Ronald S.

2018-01-01

Impaired fear extinction contributes to the persistence of post-traumatic stress disorder (PTSD), and can be utilized for the study of novel therapeutic agents. Glutamate plays an important role in the formation of traumatic memories, and in the pathophysiology and treatment of PTSD, highlighting several possible drug targets. Recent clinical studies demonstrate that infusion of ketamine, a glutamate NMDA receptor antagonist, rapidly and significantly reduces symptom severity in PTSD patients. In the present study, we examine the mechanisms underlying the actions of ketamine in a rodent model of fear conditioning, extinction, and renewal. Rats received ketamine or saline 24 h after fear conditioning and were then subjected to extinction-training on each of the following three days. Ketamine administration enhanced extinction on the second day of training (i.e., reduced freezing behavior to cue) and produced a long-lasting reduction in freezing on exposure to cue plus context 8 days later. Additionally, ketamine and extinction exposure increased levels of mTORC1 in the medial prefrontal cortex (mPFC), a region involved in the acquisition and retrieval of extinction, and infusion of the selective mTORC1 inhibitor rapamycin into the mPFC blocked the effects of ketamine on extinction. Ketamine plus extinction also increased cFos in the mPFC and administration of a glutamate-AMPA receptor antagonist blocked the effects of ketamine. These results support the hypothesis that ketamine produces long-lasting mTORC1/protein synthesis and activity dependent effects on neuronal circuits that enhance the expression of extinction and could represent a novel approach for the treatment of PTSD. PMID:28043916

Significant treatment effect of add-on ketamine anesthesia in electroconvulsive therapy in depressive patients: A meta-analysis.

PubMed

Li, Dian-Jeng; Wang, Fu-Chiang; Chu, Che-Sheng; Chen, Tien-Yu; Tang, Chia-Hung; Yang, Wei-Cheng; Chow, Philip Chik-Keung; Wu, Ching-Kuan; Tseng, Ping-Tao; Lin, Pao-Yen

2017-01-01

Add-on ketamine anesthesia in electroconvulsive therapy (ECT) has been studied in depressive patients in several clinical trials with inconclusive findings. Two most recent meta-analyses reported insignificant findings with regards to the treatment effect of add-on ketamine anesthesia in ECT in depressive patients. The aim of this study is to update the current evidence and investigate the role of add-on ketamine anesthesia in ECT in depressive patients via a systematic review and meta-analysis. We performed a thorough literature search of the PubMed and ScienceDirect databases, and extracted all relevant clinical variables to compare the antidepressive outcomes between add-on ketamine anesthesia and other anesthetics in ECT. Total 16 articles with 346 patients receiving add-on ketamine anesthesia in ECT and 329 controls were recruited. We found that the antidepressive treatment effect of add-on ketamine anesthesia in ECT in depressive patients was significantly higher than that of other anesthetics (p<0.001). This significance persisted in both short-term (1-2 weeks) and moderate-term (3-4 weeks) treatment courses (all p<0.05). However, the side effect profiles and recovery time profiles were significantly worse in add-on ketamine anesthesia group than in control group. Our meta-analysis highlights the significantly higher antidepressive treatment effect of add-on ketamine in depressive patients receiving ECT compared to other anesthetics. However, clinicians need to take undesirable side effects into consideration when using add-on ketamine anesthesia in ECT in depressive patients. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

Behavioral alterations of zebrafish larvae after early embryonic exposure to ketamine.

PubMed

Félix, Luís M; Antunes, Luís M; Coimbra, Ana M; Valentim, Ana M

2017-02-01

Ketamine has been associated with pediatric risks that include neurocognitive impairment and long-term behavioral disorders. However, the neurobehavioral effects of ketamine exposure in early development remain uncertain. This study aimed to test stage- and dose-dependent effects of ketamine exposure on certain brain functions by evaluating alterations in locomotion, anxiety-like and avoidance behaviors, as well as socialization. Embryos were exposed to different concentrations of ketamine (0, 0.2, 0.4, and 0.8 mg mL -1 ) for 20 min during the 256-cell (2.5 h post fertilization-hpf), 50% epiboly (5.5 hpf), and 1-4 somites (10.5 hpf) stages. General exploratory activities, natural escape-like responses, and social interactions were analyzed under continuous light or under a moving light stimulus. A dose-dependent decrease in the overall mean speed was perceived in the embryos exposed during the 256-cell stage. These results were related to previously observed head and eye malformations, following ketamine exposure at this stage and may indicate possible neurobehavioral disorders when ketamine exposure is performed at this stage. Results also showed that ketamine exposure during the 50% epiboly and 1-4 somites stages induced a significant increment of the anxiety-like behavior and a decrease in avoidance behavior in all exposed groups. Overall, the results validate the neurodevelopmental risks of early-life exposure to ketamine.

AMELIORATING TREATMENT-REFRACTORY DEPRESSION WITH INTRANASAL KETAMINE: POTENTIAL NMDA RECEPTOR ACTIONS IN THE PAIN CIRCUITRY REPRESENTING MENTAL ANGUISH

PubMed Central

Opler, Lewis A.; Opler, Mark G.; Arnsten, Amy F.T.

2014-01-01

This paper reviews the anti-depressant actions of the N-methyl-D-aspartame glutamate receptor (NMDAR) antagonist, ketamine, and offers a potential neural mechanism for intranasal ketamine’s ultra-rapid actions based on the key role of NMDAR in the nonhuman primate prefrontal cortex (PFC). Although intravenous ketamine infusions can lift mood within hours, the current review describes how intranasal ketamine administration can have ultra-rapid antidepressant effects, beginning within minutes (5–40 minutes) and lasting hours, but with repeated treatments needed for sustained antidepressant actions. Research in rodents suggests that increased synaptogenesis in PFC may contribute to the prolonged benefit of ketamine administration, beginning hours after administration. However, these data cannot explain the relief that occurs within minutes of intranasal ketamine delivery. We hypothesize that the ultra-rapid effects of intranasal administration in humans may be due to ketamine blocking the NMDAR circuits that generate the emotional representations of pain (e.g. Brodmann Areas 24 and 25, insular cortex), cortical areas that can be overactive in depression and which sit above the nasal epithelium. In contrast, NMDAR blockade in the dorsolateral PFC following systemic administration of ketamine may contribute to cognitive deficits. This novel view may help to explain how intravenous ketamine can treat the symptoms of depression yet worsen the symptoms of schizophrenia. PMID:25619798

Dexmedetomidine Protects Neural Stem Cells from Ketamine-Induced Injury.

PubMed

Lu, Pan; Lei, Shan; Li, Weisong; Lu, Yang; Zheng, Juan; Wang, Ning; Xia, Yongjun; Lu, Haixia; Chen, Xinlin; Liu, Yong; Zhang, Peng-Bo

2018-06-19

Ketamine inhibits the proliferation of neural stem cells (NSCs) and disturbs normal neurogenesis. Dexmedetomidine provides neuroprotection against volatile anesthetic-induced neuroapoptosis and cognitive impairment in the developing brain. Whether it may protect NSCs from ketamine-induced injury remains unknown. In this study, we investigated the protective effects of dexmedetomidine on ketamine-exposed NSCs and explored the mechanisms potentially involved. Primary NSC cultures were characterized using immunofluorescence. Cell viability was determined using a Cell Counting Kit 8 assay. Proliferation and apoptosis were assessed with BrdU incorporation and TUNEL assays, respectively. Protein levels of cleaved caspase-3, phosphorylated protein kinase B (p-Akt), and glycogen synthase kinase-3β (p-GSK-3β) were quantified using western blotting. Ket-amine significantly decreased NSC viability and proliferation and increased their apoptosis. Dexmedetomidine increased NSC proliferation and decreased their apoptosis in a dose-dependent manner. Furthermore, dexmedetomidine pretreatment notably augmented the viability and proliferation of ketamine-exposed NSCs and reduced their apoptosis. Moreover, dexmedetomidine lessened caspase-3 activation and increased p-Akt and p-GSK-3β levels in NSCs exposed to ketamine. The protective effects of dexmedetomidine on ketamine-exposed NSCs could be partly reversed by the PI3K inhibitor LY294002. Collectively, these findings indicate that dexmedetomidine may protect NSCs from ketamine-induced injury via the PI3K/Akt/GSK-3β signaling pathway. © 2018 The Author(s). Published by S. Karger AG, Basel.

Ketamine

MedlinePlus

... DEA Museum and Visitors' Center National Prevention Week Ketamine Last Updated: Wednesday, December 27, 2017 What is ... Agitation, depression, unconsciousness Hallucinations Flashbacks Read More About Ketamine Be Informed. Search for information about a drug ...

Up-regulation of insulin-like growth factor 2 by ketamine requires glycogen synthase kinase-3 inhibition.

PubMed

Grieco, Steven F; Cheng, Yuyan; Eldar-Finkelman, Hagit; Jope, Richard S; Beurel, Eléonore

2017-01-04

An antidepressant dose of the rapidly-acting ketamine inhibits glycogen synthase kinase-3 (GSK3) in mouse hippocampus, and this inhibition is required for the antidepressant effect of ketamine in learned helplessness depression-like behavior. Here we report that treatment with an antidepressant dose of ketamine (10mg/kg) increased expression of insulin-like growth factor 2 (IGF2) in mouse hippocampus, an effect that required ketamine-induced inhibition of GSK3. Ketamine also inhibited hippocampal GSK3 and increased expression of hippocampal IGF2 in mice when administered after the induction of learned helplessness. Treatment with the specific GSK3 inhibitor L803-mts was sufficient to up-regulate hippocampal IGF2 expression. Administration of IGF2 siRNA reduced ketamine's antidepressant effect in the learned helplessness paradigm. Mice subjected to the learned helplessness paradigm were separated into two groups, those that were resilient (non-depressed) and those that were susceptible (depressed). Non-depressed resilient mice displayed higher expression of IGF2 than susceptible mice. These results indicate that IGF2 contributes to ketamine's antidepressant effect and that IGF2 may confer resilience to depression-like behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

Dopamine Attenuates Ketamine-Induced Neuronal Apoptosis in the Developing Rat Retina Independent of Early Synchronized Spontaneous Network Activity.

PubMed

Dong, Jing; Gao, Lingqi; Han, Junde; Zhang, Junjie; Zheng, Jijian

2017-07-01

Deprivation of spontaneous rhythmic electrical activity in early development by anesthesia administration, among other interventions, induces neuronal apoptosis. However, it is unclear whether enhancement of neuronal electrical activity attenuates neuronal apoptosis in either normal development or after anesthesia exposure. The present study investigated the effects of dopamine, an enhancer of spontaneous rhythmic electrical activity, on ketamine-induced neuronal apoptosis in the developing rat retina. TUNEL and immunohistochemical assays indicated that ketamine time- and dose-dependently aggravated physiological and ketamine-induced apoptosis and inhibited early-synchronized spontaneous network activity. Dopamine administration reversed ketamine-induced neuronal apoptosis, but did not reverse the inhibitory effects of ketamine on early synchronized spontaneous network activity despite enhancing it in controls. Blockade of D1, D2, and A2A receptors and inhibition of cAMP/PKA signaling partially antagonized the protective effect of dopamine against ketamine-induced apoptosis. Together, these data indicate that dopamine attenuates ketamine-induced neuronal apoptosis in the developing rat retina by activating the D1, D2, and A2A receptors, and upregulating cAMP/PKA signaling, rather than through modulation of early synchronized spontaneous network activity.

Oral ketamine for children with chronic pain: a pilot phase 1 study

PubMed Central

Bredlau, Amy-Lee; McDermott, Michael P.; Adams, Heather; Dworkin, Robert H; Venuto, Charles; Fisher, Susan; Dolan, James G; Korones, David N

2013-01-01

Objective To assess whether oral ketamine aids is is safe at higher dosages for sedating children and whether it may be an option for control of chronic pain in children. Study design A prospective study was performed on 12 children with chronic pain to identify the maximum tolerated dosage of oral ketamine. Participants were given 14 days of oral ketamine, three times daily, at dosages ranging from 0.25–1.5 mg/kg/dose. Participants were assessed for toxicity and for pain severity at baseline and on day 14 of treatment. Results Two participants, both treated at 1.5 mg/kg/dose, experienced dose-limiting toxicities (sedation and anorexia). One participant, treated at 1 mg/kg/dose, opted to stop ketamine treatment due to new pain on treatment. Nine participants completed their course of ketamine treatment. Of these 12 children, 5 experienced improvement in their pain scores, two with complete resolution of pain, lasting for more than 4 weeks off ketamine treatment. Conclusion Oral ketamine at dosages of 0.25–1 mg/kg/dose appears to be safe when given for 14 days to children with chronic pain. PMID:23403253

Ketamine has distinct electrophysiological and behavioral effects in depressed and healthy subjects.

PubMed

Nugent, Allison C; Ballard, Elizabeth D; Gould, Todd D; Park, Lawrence T; Moaddel, Ruin; Brutsche, Nancy E; Zarate, Carlos A

2018-02-27

Ketamine's mechanism of action was assessed using gamma power from magnetoencephalography (MEG) as a proxy measure for homeostatic balance in 35 unmedicated subjects with major depressive disorder (MDD) and 25 healthy controls enrolled in a double-blind, placebo-controlled, randomized cross-over trial of 0.5 mg/kg ketamine. MDD subjects showed significant improvements in depressive symptoms, and healthy control subjects exhibited modest but significant increases in depressive symptoms for up to 1 day after ketamine administration. Both groups showed increased resting gamma power following ketamine. In MDD subjects, gamma power was not associated with the magnitude of the antidepressant effect. However, baseline gamma power was found to moderate the relationship between post-ketamine gamma power and antidepressant response; specifically, higher post-ketamine gamma power was associated with better response in MDD subjects with lower baseline gamma, with an inverted relationship in MDD subjects with higher baseline gamma. This relationship was observed in multiple regions involved in networks hypothesized to be involved in the pathophysiology of MDD. This finding suggests biological subtypes based on the direction of homeostatic dysregulation and has important implications for inferring ketamine's mechanism of action from studies of healthy controls alone.

Up-regulation of insulin-like growth factor 2 by ketamine requires glycogen synthase kinase-3 inhibition

PubMed Central

Grieco, Steven F.; Cheng, Yuyan; Eldar-Finkelman, Hagit; Jope, Richard S.; Beurel, Eléonore

2016-01-01

An antidepressant dose of the rapidly-acting ketamine inhibits glycogen synthase kinase-3 (GSK3) in mouse hippocampus, and this inhibition is required for the antidepressant effect of ketamine in learned helplessness depression-like behavior. Here we report that treatment with an antidepressant dose of ketamine (10 mg/kg) increased expression of insulin-like growth factor 2 (IGF2) in mouse hippocampus, an effect that required ketamine-induced inhibition of GSK3. Ketamine also inhibited hippocampal GSK3 and increased expression of hippocampal IGF2 in mice when administered after the induction of learned helplessness. Treatment with the specific GSK3 inhibitor L803-mts was sufficient to up-regulate hippocampal IGF2 expression. Administration of IGF2 siRNA reduced ketamine's antidepressant effect in the learned helplessness paradigm. Mice subjected to the learned helplessness paradigm were separated into two groups, those that were resilient (non-depressed) and those that were susceptible (depressed). Non-depressed resilient mice displayed higher expression of IGF2 than susceptible mice. These results indicate that IGF2 contributes to ketamine's antidepressant effect and that IGF2 may confer resilience to depression-like behavior. PMID:27542584

Ketamine: 50 Years of Modulating the Mind

PubMed Central

Li, Linda; Vlisides, Phillip E.

2016-01-01

Ketamine was introduced into clinical practice in the 1960s and continues to be both clinically useful and scientifically fascinating. With considerably diverse molecular targets and neurophysiological properties, ketamine’s effects on the central nervous system remain incompletely understood. Investigators have leveraged the unique characteristics of ketamine to explore the invariant, fundamental mechanisms of anesthetic action. Emerging evidence indicates that ketamine-mediated anesthesia may occur via disruption of corticocortical information transfer in a frontal-to-parietal (“top down”) distribution. This proposed mechanism of general anesthesia has since been demonstrated with anesthetics in other pharmacological classes as well. Ketamine remains invaluable to the fields of anesthesiology and critical care medicine, in large part due to its ability to maintain cardiorespiratory stability while providing effective sedation and analgesia. Furthermore, there may be an emerging role for ketamine in treatment of refractory depression and Post-Traumatic Stress Disorder. In this article, we review the history of ketamine, its pharmacology, putative mechanisms of action and current clinical applications. PMID:27965560

Ketamine PCA for treatment of end-of-life neuropathic pain in pediatrics.

PubMed

Taylor, Matthew; Jakacki, Regina; May, Carol; Howrie, Denise; Maurer, Scott

2015-12-01

Control of neuropathic pain (NP) for children at end of life is challenging. Ketamine improves control of NP, but its use in children is not well described. We describe a retrospective case review of 14 children with terminal prognoses treated with ketamine patient-controlled analgesia (PCA) for management of opioid-refractory NP at the end of life. Median ketamine dose was 0.06 mg/kg/h (range 0.014-0.308 mg/kg/h) with a 0.05 mg/kg (range 0.03-0.5mg/kg) demand dose available every 15 minutes (range 10-60 minutes). All patients noted subjective pain relief with ketamine, and 79% had no adverse effects. Benzodiazepines limited neuropsychiatric side effects. Ketamine treatment arrested dose escalation of opioids in 64% of patients, and 79% were discharged to home hospice. Ketamine PCA is an effective, well-tolerated therapy for opioid-refractory NP in pediatric end-of-life care. © The Author(s) 2014.

Ketamine as an Adjunct to Opioids for Acute Pain in the Emergency Department: A Randomized Controlled Trial.

PubMed

Bowers, Karen J; McAllister, Kelly B; Ray, Meredith; Heitz, Corey

2017-06-01

This study had five objectives: 1) to measure and compare total opioid use and number of opioid doses in patients treated with opioids versus ketamine in conjunction with opioids; 2) to measure pain scores up to 2 hours after presentation in the ED patient with pain, comparing standard opioid pain control to ketamine in conjunction with opioids; 3) to compare patient satisfaction with pain control using opioids alone versus ketamine in conjunction with opioids; 4) to monitor and compare side effects in patients treated with opioids versus ketamine in conjunction with opioids; and 5) to identify effect variation between different subgroups of patients, with the purpose of focusing future research. We hypothesized that low-dose ketamine, compared to placebo, as an adjunctive treatment to opioids would result in better pain control over 2 hours and greater patient satisfaction with pain control; further, this protocol will result in a lower opioid dosage over 2 hours. This was a randomized, double-blinded, placebo-controlled trial at a single academic emergency department evaluating the use of ketamine versus placebo in conjunction with opioids for moderate to severe pain. Subjects with a continued high level of pain after an initial dose of opioid analgesia were randomized to receive either 0.1 mg/kg ketamine or placebo prior to protocol-based dosing of additional opioid analgesia, if required. Over 120 minutes, subjects were assessed for pain level (0-10), satisfaction with pain control (0-4), side effects, sedation level, and need for additional pain medication. Total opioid dose, including the initial dose, was compared between groups. Sixty-three subjects were randomized to the placebo group and 53 to the ketamine group. No significant differences were found in demographics between the groups. Patients receiving ketamine reported lower pain scores over 120 minutes than patients receiving placebo (p = 0.015). Total opioid dose was lower in the ketamine group (mean ± SD = 9.95 ± 4.83 mg) compared to placebo (mean ± SD = 12.81 ± 6.81 mg; p = 0.02). Satisfaction did not differ between groups. Fewer patients in the ketamine group required additional opioid doses. More patients reported light-headedness and dizziness in the ketamine group. Ketamine, as an adjunct to opioid therapy, was more effective at reducing pain over 120 minutes and resulted in a lower total opioid dose as well as fewer repeat doses of analgesia. More side effects were reported in the ketamine group (51% vs. 19%), but the side effect profile appears tolerable. © 2017 by the Society for Academic Emergency Medicine.

Intraoperative ketamine for prevention of postoperative delirium or pain after major surgery in older adults: an international, multicentre, double-blind, randomised clinical trial.

PubMed

Avidan, Michael S; Maybrier, Hannah R; Abdallah, Arbi Ben; Jacobsohn, Eric; Vlisides, Phillip E; Pryor, Kane O; Veselis, Robert A; Grocott, Hilary P; Emmert, Daniel A; Rogers, Emma M; Downey, Robert J; Yulico, Heidi; Noh, Gyu-Jeong; Lee, Yonghun H; Waszynski, Christine M; Arya, Virendra K; Pagel, Paul S; Hudetz, Judith A; Muench, Maxwell R; Fritz, Bradley A; Waberski, Witold; Inouye, Sharon K; Mashour, George A

2017-07-15

Delirium is a common and serious postoperative complication. Subanaesthetic ketamine is often administered intraoperatively for postoperative analgesia, and some evidence suggests that ketamine prevents delirium. The primary purpose of this trial was to assess the effectiveness of ketamine for prevention of postoperative delirium in older adults. The Prevention of Delirium and Complications Associated with Surgical Treatments [PODCAST] study is a multicentre, international randomised trial that enrolled adults older than 60 years undergoing major cardiac and non-cardiac surgery under general anaesthesia. Using a computer-generated randomisation sequence we randomly assigned patients to one of three groups in blocks of 15 to receive placebo (normal saline), low-dose ketamine (0·5 mg/kg), or high dose ketamine (1·0 mg/kg) after induction of anaesthesia, before surgical incision. Participants, clinicians, and investigators were blinded to group assignment. Delirium was assessed twice daily in the first 3 postoperative days using the Confusion Assessment Method. We did analyses by intention-to-treat and assessed adverse events. This trial is registered with clinicaltrials.gov, number NCT01690988. Between Feb 6, 2014, and June 26, 2016, 1360 patients were assessed, and 672 were randomly assigned, with 222 in the placebo group, 227 in the 0·5 mg/kg ketamine group, and 223 in the 1·0 mg/kg ketamine group. There was no difference in delirium incidence between patients in the combined ketamine groups and the placebo group (19·45% vs 19·82%, respectively; absolute difference 0·36%, 95% CI -6·07 to 7·38, p=0·92). There were more postoperative hallucinations (p=0·01) and nightmares (p=0·03) with increasing ketamine doses compared with placebo. Adverse events (cardiovascular, renal, infectious, gastrointestinal, and bleeding), whether viewed individually (p value for each >0·40) or collectively (36·9% in placebo, 39·6% in 0·5 mg/kg ketamine, and 40·8% in 1·0 mg/kg ketamine groups, p=0·69), did not differ significantly across groups. A single subanaesthetic dose of ketamine did not decrease delirium in older adults after major surgery, and might cause harm by inducing negative experiences. National Institutes of Health and Cancer Center Support. Copyright © 2017 Elsevier Ltd. All rights reserved.

Magnetic resonance cholangiogram patterns and clinical profiles of ketamine-related cholangiopathy in drug users.

PubMed

Seto, Wai-Kay; Mak, Siu-King; Chiu, Keith; Vardhanabhuti, Varut; Wong, Ho-Fai; Leong, Heng-Tat; Lee, Paul S F; Ho, Y C; Lee, Chi-Kei; Cheung, Ka-Shing; Yuen, Man-Fung; Leung, Wai K

2018-07-01

Recreational ketamine use has emerged as an important health and social issue worldwide. Although ketamine is associated with biliary tract damage, the clinical and radiological profiles of ketamine-related cholangiopathy have not been well described. Chinese individuals who had used ketamine recreationally at least twice per month for six months in the previous two years via a territory-wide community network of charitable organizations tackling substance abuse were recruited. Magnetic resonance cholangiography (MRC) was performed, and the findings were interpreted independently by two radiologists, with the findings analysed in association with clinical characteristics. Among the 343 ketamine users referred, 257 (74.9%) were recruited. The mean age and ketamine exposure duration were 28.7 (±5.8) and 10.5 (±3.7) years, respectively. A total of 159 (61.9%) had biliary tract anomalies on MRC, categorized as diffuse extrahepatic dilatation (n = 73), fusiform extrahepatic dilatation (n = 64), and intrahepatic ductal changes (n = 22) with no extrahepatic involvement. Serum alkaline phosphatase (ALP) level (odds ratio [OR] 1.007; 95% CI 1.002-1.102), lack of concomitant recreational drug use (OR 1.99; 95% CI 1.11-3.58), and prior emergency attendance for urinary symptoms (OR 1.95; 95% CI 1.03-3.70) had high predictive values for biliary anomalies on MRC. Among sole ketamine users, ALP level had an AUC of 0.800 in predicting biliary anomalies, with an optimal level of ≥113 U/L having a positive predictive value of 85.4%. Cholangiographic anomalies were reversible after ketamine abstinence, whereas decompensated cirrhosis and death were possible after prolonged exposure. We have identified distinctive MRC patterns in a large cohort of ketamine users. ALP level and lack of concomitant drug use predicted biliary anomalies, which were reversible after abstinence. The study findings may aid public health efforts in combating the growing epidemic of ketamine abuse. Recreational inhalation of ketamine is currently an important substance abuse issue worldwide, and can result in anomalies of the biliary system as demonstrated by magnetic resonance imaging. Although prolonged exposure may lead to further clinical deterioration, such biliary system anomalies might be reversible after ketamine abstinence. Clinical trial number: NCT02165488. Copyright © 2018 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Ketamine inhibits tumor necrosis factor-{alpha} and interleukin-6 gene expressions in lipopolysaccharide-stimulated macrophages through suppression of toll-like receptor 4-mediated c-Jun N-terminal kinase phosphorylation and activator protein-1 activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, G.-J.; Department of Anesthesiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan

2008-04-01

Our previous study showed that ketamine, an intravenous anesthetic agent, has anti-inflammatory effects. In this study, we further evaluated the effects of ketamine on the regulation of tumor necrosis factor-{alpha} (TNF-{alpha}) and interlukin-6 (IL-6) gene expressions and its possible signal-transducing mechanisms in lipopolysaccharide (LPS)-activated macrophages. Exposure of macrophages to 1, 10, and 100 {mu}M ketamine, 100 ng/ml LPS, or a combination of ketamine and LPS for 1, 6, and 24 h was not cytotoxic to macrophages. A concentration of 1000 {mu}M of ketamine alone or in combined treatment with LPS caused significant cell death. Administration of LPS increased cellular TNF-{alpha}more » and IL-6 protein levels in concentration- and time-dependent manners. Meanwhile, treatment with ketamine concentration- and time-dependently alleviated the enhanced effects. LPS induced TNF-{alpha} and IL-6 mRNA syntheses. Administration of ketamine at a therapeutic concentration (100 {mu}M) significantly inhibited LPS-induced TNF-{alpha} and IL-6 mRNA expressions. Application of toll-like receptor 4 (TLR4) small interfering (si)RNA into macrophages decreased cellular TLR4 levels. Co-treatment of macrophages with ketamine and TLR4 siRNA decreased the LPS-induced TNF-{alpha} and IL-6 productions more than alone administration of TLR4 siRNA. LPS stimulated phosphorylation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos from the cytoplasm to nuclei. However, administration of ketamine significantly decreased LPS-induced activation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos. LPS increased the binding of nuclear extracts to activator protein-1 consensus DNA oligonucleotides. Administration of ketamine significantly ameliorated LPS-induced DNA binding activity of activator protein-1. Therefore, a clinically relevant concentration of ketamine can inhibit TNF-{alpha} and IL-6 gene expressions in LPS-activated macrophages. The suppressive mechanisms occur through suppression of TLR4-mediated sequential activations of c-Jun N-terminal kinase and activator protein-1.« less

Neuronal correlates of ketamine and walking induced gamma oscillations in the medial prefrontal cortex and mediodorsal thalamus.

PubMed

Furth, Katrina E; McCoy, Alex J; Dodge, Caroline; Walters, Judith R; Buonanno, Andres; Delaville, Claire

2017-01-01

Alterations in the function of the medial prefrontal cortex (mPFC) and its major thalamic source of innervation, the mediodorsal (MD) thalamus, have been hypothesized to contribute to the symptoms of schizophrenia. The NMDAR antagonist ketamine, used to model schizophrenia, elicits a brain state resembling early stage schizophrenia characterized by cognitive deficits and increases in cortical low gamma (40-70 Hz) power. Here we sought to determine how ketamine differentially affects spiking and gamma local field potential (LFP) activity in the rat mPFC and MD thalamus. Additionally, we investigated the ability of drugs targeting the dopamine D4 receptor (D4R) to modify the effects of ketamine on gamma activity as a measure of potential cognitive therapeutic efficacy. Rats were trained to walk on a treadmill to reduce confounds related to hyperactivity after ketamine administration (10 mg/kg s.c.) while recordings were obtained from electrodes chronically implanted in the mPFC and MD thalamus. Ketamine increased gamma LFP power in mPFC and MD thalamus in a similar frequency range, yet did not increase thalamocortical synchronization. Ketamine also increased firing rates and spike synchronization to gamma oscillations in the mPFC but decreased both measures in MD thalamus. Conversely, walking alone increased both firing rates and spike-gamma LFP correlations in both mPFC and MD thalamus. The D4R antagonist alone (L-745,870) had no effect on gamma LFP power during treadmill walking, although it reversed increases induced by the D4R agonist (A-412997) in both mPFC and MD thalamus. Neither drug altered ketamine-induced changes in gamma power or firing rates in the mPFC. However, in MD thalamus, the D4R agonist increased ketamine-induced gamma power and prevented ketamine's inhibitory effect on firing rates. Results provide new evidence that ketamine differentially modulates spiking and gamma power in MD thalamus and mPFC, supporting a potential role for both areas in contributing to ketamine-induced schizophrenia-like symptoms.

Ketamine inhibits tumor necrosis factor-alpha and interleukin-6 gene expressions in lipopolysaccharide-stimulated macrophages through suppression of toll-like receptor 4-mediated c-Jun N-terminal kinase phosphorylation and activator protein-1 activation.

PubMed

Wu, Gone-Jhe; Chen, Ta-Liang; Ueng, Yune-Fang; Chen, Ruei-Ming

2008-04-01

Our previous study showed that ketamine, an intravenous anesthetic agent, has anti-inflammatory effects. In this study, we further evaluated the effects of ketamine on the regulation of tumor necrosis factor-alpha (TNF-alpha) and interlukin-6 (IL-6) gene expressions and its possible signal-transducing mechanisms in lipopolysaccharide (LPS)-activated macrophages. Exposure of macrophages to 1, 10, and 100 microM ketamine, 100 ng/ml LPS, or a combination of ketamine and LPS for 1, 6, and 24 h was not cytotoxic to macrophages. A concentration of 1000 microM of ketamine alone or in combined treatment with LPS caused significant cell death. Administration of LPS increased cellular TNF-alpha and IL-6 protein levels in concentration- and time-dependent manners. Meanwhile, treatment with ketamine concentration- and time-dependently alleviated the enhanced effects. LPS induced TNF-alpha and IL-6 mRNA syntheses. Administration of ketamine at a therapeutic concentration (100 microM) significantly inhibited LPS-induced TNF-alpha and IL-6 mRNA expressions. Application of toll-like receptor 4 (TLR4) small interfering (si)RNA into macrophages decreased cellular TLR4 levels. Co-treatment of macrophages with ketamine and TLR4 siRNA decreased the LPS-induced TNF-alpha and IL-6 productions more than alone administration of TLR4 siRNA. LPS stimulated phosphorylation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos from the cytoplasm to nuclei. However, administration of ketamine significantly decreased LPS-induced activation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos. LPS increased the binding of nuclear extracts to activator protein-1 consensus DNA oligonucleotides. Administration of ketamine significantly ameliorated LPS-induced DNA binding activity of activator protein-1. Therefore, a clinically relevant concentration of ketamine can inhibit TNF-alpha and IL-6 gene expressions in LPS-activated macrophages. The suppressive mechanisms occur through suppression of TLR4-mediated sequential activations of c-Jun N-terminal kinase and activator protein-1.

Development and validation of an HPLC-MS/MS method for the detection of ketamine in Calliphora vomitoria (L.) (Diptera: Calliphoridae).

PubMed

Magni, Paola A; Pazzi, Marco; Droghi, Jessica; Vincenti, Marco; Dadour, Ian R

2018-05-03

Entomotoxicology is a branch of forensic entomology that studies the detection of drugs or other toxic substances from insects developing on the decomposing tissues of a human corpse or animal carcass. Entomotoxicology also investigates the effects of these substances on insect development, survival and morphology to provide an estimation of the minimum time since death. Ketamine is a medication mainly used for starting and maintaining anesthesia. In recent years ketamine has also been used as a recreational drug, and occasionally as a sedating drug to facilitate sexual assault. In both activities, it has resulted in several deaths. Furthermore, ketamine has been also implicated in suspicious deaths of animals. The present research describes for the first time the development and validation of an analytical method suited to detect ketamine in larvae, pupae, empty puparia, and adults of Calliphora vomitoria L. (Diptera: Calliphoridae), using liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). This research also considers the effects of ketamine on the survival, developmental rate and morphology (length and width of larvae and pupae) of C. vomitoria. The larvae were reared on liver substrates homogeneously spiked with ketamine concentrations consistent with those found in humans after recreational use (300 ng/mg) or allegedly indicated as capable of causing death in either humans or animals (600 ng/mg). The results demonstrated that (a) HPLC-MS/MS method is applicable to ketamine detection in C. vomitoria immatures, not adults; (b) the presence of ketamine at either concentration in the food substrate significantly delays the developmental time to pupal and adult instar; (d) the survival of C. vomitoria is negatively affected by the presence of ketamine in the substrate; (e) the length and width of larvae and pupae exposed to either ketamine concentration were significantly larger than the control samples. Copyright © 2018. Published by Elsevier Ltd.

Ketamine potentiates hippocampal neurodegeneration and persistent learning and memory impairment through the PKCγ-ERK signaling pathway in the developing brain.

PubMed

Huang, Lining; Liu, Ya; Jin, Wei; Ji, Xiaochen; Dong, Zhenming

2012-10-02

Ketamine, an N-methyl-d-aspartate (NMDA) receptor antagonist, is widely used as a general pediatric anesthetic. Recent studies suggest that ketamine enhances neuronal apoptosis in developing rodents and nonhuman primates. The main goal of this study is to determine whether ketamine causes hippocampal neurodegeneration and behavioral deficits in adulthood, and if so, whether the effects of ketamine are associated with protein kinase C-gamma (PKCγ), extracellular signal regulated kinase (ERK)1/2 and Bcl-2 expression. Starting from postnatal day 7, Sprague-Dawley rat pups randomly received daily ketamine treatment (25, 50 and 75mg/kg, ip) for three consecutive days. Twenty-four hours after the last treatment with ketamine, the rats were decapitated, and the hippocampi were isolated for detection of neuronal apoptosis by TUNEL. The protein expression levels of PKCγ, ERK1/2 and Bcl-2 in the hippocampi were measured by western blot analysis. At 2months of age, learning and memory abilities were tested by the Morris water maze. Ketamine increased the number of apoptotic cells in the CA1 region and dentate gyrus at a dose of 75mg/kg but not at lower doses of 25 and 50mg/kg. The dose of 75mg/kg of ketamine suppressed p-PKCγ, p-ERK1/2 and Bcl-2 expression but not t-PKCγ or t-ERK expression. Ketamine administered to the developing brains of P7 rats at a dose of 75mg/kg caused learning and memory impairments in adulthood. Therefore, these data demonstrate that ketamine at a dose of 75mg/kg in the developing brain results in hippocampal neurodegeneration and persistent learning and memory impairment, which is associated with the PKCγ-ERK signaling pathway. This article is part of a Special Issue entitled: Brain Integration. Copyright © 2012 Elsevier B.V. All rights reserved.

Ketamine: An Update on Cellular and Subcellular Mechanisms with Implications for Clinical Practice.

PubMed

Iacobucci, Gary J; Visnjevac, Ognjen; Pourafkari, Leili; Nader, Nader Djalal

2017-02-01

Ketamine is one of the oldest hypnotic agents used to provide an anesthetic agent with analgesic properties and minimal suppressive effects on respiration. The ability of ketamine in modulating glutamatergic (N-methyl D-aspartate) pain receptors has made this anesthetic drug a new option for the management of patients with chronic pain syndromes. Further preclinical and clinical findings suggest ketamine may have wide ranging effects on both cognition and development. Recent advances have revealed an unprecedented role for ketamine in the acute management of depression. The purpose of this review is to integrate a number of basic science, preclinical, and clinical studies with the goal of providing insight into the possible signaling events underlying ketamine's biological effects in pain management, depression, cognition and memory, and neurodevelopment. Narrative literature review. Health science library. A comprehensive literature search was performed for the following medical subject headings and keywords (ketamine, anesthesia, pain, analgesia, depression, NMDA receptors) on PubMed, Google Scholar, and Medline from 1966 to the present time. The search was then limited to those in the English language. The full text of the relevant articles were printed and reviewed by all authors. We provided a comprehensive review of the literature that explored the pharmacologic aspects of ketamine from its conception as an anesthetic to its evolution as a drug used for treatment of depression and pain. To address the patient response variability observed in clinical studies, we have provided possible patient-specific factors that could contribute to outcome variability. Like any review, this study was limited by publication bias and missing information on negative studies which were denied publication. Ketamine, an old anesthetic agent with analgesic properties, is currently being considered for treating patients with chronic pain and depression. The complex pharmacological characteristics of ketamine make this medication a multifaceted therapeutic option in these cases. Key Words: Ketamine, anesthetics, pain, depression, pharmacology.

The parasympatholytic effects of atropine sulfate and glycopyrrolate in rats and rabbits.

PubMed Central

Olson, M E; Vizzutti, D; Morck, D W; Cox, A K

1994-01-01

Nine groups of rats (n = 5 per group) received an intramuscular (IM) injection of one of the following drugs or drug combinations: saline, atropine (0.05 mg/kg), glycopyrrolate (0.5 mg/kg), ketamine:xylazine (85:15 mg/kg), ketamine:detomidine (60:10 mg/kg), atropine:ketamine:xylazine (0.05: 85:15 mg/kg), glycopyrrolate: ketamine:xylazine (0.5:85:15 mg/kg), atropine:ketamine:detomidine (0.05: 60:10 mg/kg) or glycopyrrolate: ketamine:detomidine (0.5:60:10). Similarly six groups of rabbits (n = 5) received an IM injection of either saline, atropine (0.2 mg/kg), atropine (2 mg/kg), glycopyrrolate (0.1 mg/kg), ketamine:xylazine (35:10 mg/kg) or glycopyrrolate:ketamine:xylazine (0.1:35:10 mg/kg). In rats, atropine sulfate (0.05 mg/kg) and glycopyrrolate (0.5 mg/kg) produced an increase in heart rate for 30 and 240 min, respectively. In rabbits atropine sulfate at either 0.2 or 2.0 mg/kg did not induce a significant increase in heart rate, but glycopyrrolate (0.1 mg/kg) elevated the heart rate above saline treated animals for over 50 min. Both atropine and glycopyrrolate provided protection against a decrease in heart rate in rats anesthetized with ketamine: xylazine (85:15 mg/kg) or ketamine: detomidine (60:10 mg/kg); however, glycopyrrolate was significantly more effective in maintaining the heart rate within the normal range. Glycopprrolate also prevented a decrease in heart rate in rabbits anesthetized with ketamine:xylazine (35:5 mg/kg). Neither glycopyrrolate nor atropine influenced respiration rate, core body temperature or systolic blood pressure when used alone or when combined with the injectable anesthetic. Glycopyrrolate is an effective anticholinergic agent in rabbits and rodents and more useful as a preanesthetic agent than atropine sulfate in these animals. PMID:7889456

Antisuicidal Response Following Ketamine Infusion Is Associated With Decreased Nighttime Wakefulness in Major Depressive Disorder and Bipolar Disorder.

PubMed

Vande Voort, Jennifer L; Ballard, Elizabeth D; Luckenbaugh, David A; Bernert, Rebecca A; Richards, Erica M; Niciu, Mark J; Park, Lawrence T; Machado-Vieira, Rodrigo; Duncan, Wallace C; Zarate, Carlos A

Insomnia and disrupted sleep are associated with increased risk of suicide. The N-methyl-d-aspartate antagonist ketamine has been associated with reduced suicidal thoughts, but the mechanism of action is unknown. This study sought to evaluate differences in nocturnal wakefulness in depressed individuals who did and did not have an antisuicidal response to ketamine. Thirty-four participants with baseline suicidal ideation diagnosed with either DSM-IV major depressive disorder (n = 23) or bipolar depression (n = 11) between 2006 and 2013 completed nighttime electroencephalography (EEG) the night before and the night after a single ketamine infusion (0.5 mg/kg over 40 minutes). Suicidal ideation was assessed at baseline and the morning after ketamine infusion via several measures, including the Hamilton Depression Rating Scale suicide item, the suicide item of the Montgomery-Asberg Depression Rating Scale, and the first 5 items of the Scale for Suicide Ideation. A generalized linear mixed model evaluated differences in nocturnal wakefulness, as verified by EEG, between those who had an antisuicidal response to ketamine and those who did not, controlling for baseline nocturnal wakefulness. Results were also compared to the sleep of healthy controls (n = 22). After analyses adjusted for baseline sleep, participants with an antisuicidal response to ketamine showed significantly reduced nocturnal wakefulness the night after ketamine infusion compared to those without an antisuicidal response (F₁,₂₂ = 5.04, P = .04). Level of nocturnal wakefulness after antisuicidal response to ketamine did not differ significantly from nocturnal wakefulness in the control sample but did differ at a trend level (F₁,₄₀ = 3.15, P = .08). Reductions in wakefulness following ketamine may point to a biological mechanism underlying the effect of ketamine on suicidal ideation. ClinicalTrials.gov identifier: NCT00088699. © Copyright 2016 Physicians Postgraduate Press, Inc.

The role of a low-dose ketamine-midazolam regimen in the management of severe painful crisis in patients with sickle cell disease.

PubMed

Tawfic, Qutaiba A; Faris, Ali S; Kausalya, Rajini

2014-02-01

Acute pain is one of the main causes of hospital admission in sickle cell disease, with variable intensity and unpredictable onset and duration. We studied the role of a low-dose intravenous (IV) ketamine-midazolam combination in the management of severe painful sickle cell crisis. A retrospective analysis was performed with data from nine adult patients who were admitted to the intensive care unit with severe painful sickle cell crises not responding to high doses of IV morphine and other adjuvant analgesics. A ketamine-midazolam regimen was added to the ongoing opioids as an initial bolus of ketamine 0.25mg/kg, followed by infusion of 0.2-0.25mg/kg/h. A midazolam bolus of 1mg followed by infusion of 0.5-1mg/h was added to reduce ketamine emergence reactions. Reduction in morphine daily requirements and improvement in pain scores were the determinants of ketamine-midazolam effect. The t-tests were used for statistical analysis. Nine patients were assessed, with mean age of 27±11 years. Morphine requirement was significantly lower after adding the IV ketamine-midazolam regimen. The mean±SD IV morphine requirement (milligram/day) in the pre-ketamine day (D0) was 145.6±16.5, and it was 112±12.2 on Day 1 (D1) of ketamine treatment (P=0.007). The Numeric Rating Scale scores on D0 ranged from eight to ten (mean 9.1), but improved to range from five to seven (mean 5.7) on D1. There was a significant improvement in pain scores after adding ketamine-midazolam regimen (P=0.01). Low-dose ketamine-midazolam IV infusion might be effective in reducing pain and opioid requirements in patients with sickle cell disease with severe painful crisis. Further controlled studies are required to prove this effect. Copyright © 2014 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

The effects of pentobarbital, ketamine-pentobarbital and ketamine-xylazine anesthesia in a rat myocardial ischemic reperfusion injury model.

PubMed

Shekarforoush, Shahnaz; Fatahi, Zahra; Safari, Fatemeh

2016-06-01

To achieve reliable experimental data, the side-effects of anesthetics should be eliminated. Since anesthetics exert a variety of effects on hemodynamic data and incidence of arrhythmias, the selection of anesthetic agents in a myocardial ischemic reperfusion injury model is very important. The present study was performed to compare hemodynamic variables, the incidence of ventricular arrhythmias, and infarct size during 30 min of ischemia and 120 min of reperfusion in rats using pentobarbital, ketamine-pentobarbital or ketamine-xylazine anaesthesia. A total of 30 rats were randomly divided into three groups. In group P, pentobarbital (60 mg/kg, intraperitoneally [IP]) was used solely; in group K-P, ketamine and pentobarbital (50 and 30 mg/kg, respectively, IP) were used in combination; and in group K-X, ketamine and xylazine (75 and 5 mg/kg, respectively, IP) were also used in combination. Hemodynamic data and occurrence of ventricular arrhythmias were recorded throughout the experiments. The ischemic area was measured by triphenyltetrazolium chloride staining. The combination of ketamine-xylazine caused bradycardia and hypotension. The greatest reduction in mean arterial blood pressure during ischemia was in the P group. The most stability in hemodynamic parameters during ischemia and reperfusion was in the K-P group. The infarct size was significantly less in the K-X group. Whereas none of the rats anesthetized with ketamine-xylazine fibrillated during ischemia, ventricular fibrillation occurred in 57% of the animals anesthetized with pentobarbital or ketamine-pentobarbital. Because it offers the most stable hemodynamic parameters, it is concluded that the ketamine-pentobarbital anesthesia combination is the best anesthesia in a rat ischemia reperfusion injury model. © The Author(s) 2015.

Three-phase Bone Scintigraphy Can Predict the Analgesic Efficacy of Ketamine Therapy in CRPS.

PubMed

Sorel, Marc; Beatrix, Jacques-Christian; Locko, Blanche; Armessen, Catherine; Domec, Anne-Marie; Lecompte, Otilia; Boucheneb, Sofiane; Harache, Benoit; Robert, Jacques; Lefaucheur, Jean-Pascal

2018-03-13

The efficacy of ketamine in relieving complex regional pain syndrome (CRPS) lacks predictive factors. The value of three-phase bone scintigraphy (TPBS) was assessed or this purpose. TPBS was performed in 105 patients with unilateral, focal CRPS of type 1 before 5 days of ketamine infusions. Tracer uptake was measured in the region of interest concerned by CRPS and the contralateral homologous region. For the three scintigraphic phases (vascular, tissular, and bone phases), an asymmetry ratio of fixation was calculated between the affected and the unaffected sides (VPr, TPr, and BPr). Ketamine efficacy was assessed on pain intensity scores. Ketamine-induced pain relief did not correlate with VPr, TPr, and BPr, but with the ratios of these ratios: BPr/TPr (r=0.32, P=0.009), BPr/VPr (r=0.34, P=0.005), and TPr/VPr (r=0.23, P=0.02). The optimum cut-off value for predicting the response to ketamine therapy was >1.125 for BPr/TPr, >1.075 for BPr/VPr, and >0.935 for TPr/VPr. The combination of increased values of BPr/TPr, BPr/VPr, and TPr/VPr was extremely significantly associated with ketamine therapy outcome. The relative hyperfixation of the radioactive tracer in the limb region concerned by CRPS in phases 2 and 3 versus phase 1 of TPBS correlated positively to the analgesic efficacy of ketamine. This study shows for the first time the potential predictive value of TPBS regarding ketamine therapy outcome. In addition, these results suggest that the analgesic action of ketamine is not restricted to "central" mechanisms, but may also involve "peripheral" mechanisms related to tissue inflammation and bone remodeling.

Resting-state Network-specific Breakdown of Functional Connectivity during Ketamine Alteration of Consciousness in Volunteers.

PubMed

Bonhomme, Vincent; Vanhaudenhuyse, Audrey; Demertzi, Athena; Bruno, Marie-Aurélie; Jaquet, Oceane; Bahri, Mohamed Ali; Plenevaux, Alain; Boly, Melanie; Boveroux, Pierre; Soddu, Andrea; Brichant, Jean François; Maquet, Pierre; Laureys, Steven

2016-11-01

Consciousness-altering anesthetic agents disturb connectivity between brain regions composing the resting-state consciousness networks (RSNs). The default mode network (DMn), executive control network, salience network (SALn), auditory network, sensorimotor network (SMn), and visual network sustain mentation. Ketamine modifies consciousness differently from other agents, producing psychedelic dreaming and no apparent interaction with the environment. The authors used functional magnetic resonance imaging to explore ketamine-induced changes in RSNs connectivity. Fourteen healthy volunteers received stepwise intravenous infusions of ketamine up to loss of responsiveness. Because of agitation, data from six subjects were excluded from analysis. RSNs connectivity was compared between absence of ketamine (wake state [W1]), light ketamine sedation, and ketamine-induced unresponsiveness (deep sedation [S2]). Increasing the depth of ketamine sedation from W1 to S2 altered DMn and SALn connectivity and suppressed the anticorrelated activity between DMn and other brain regions. During S2, DMn connectivity, particularly between the medial prefrontal cortex and the remaining network (effect size β [95% CI]: W1 = 0.20 [0.18 to 0.22]; S2 = 0.07 [0.04 to 0.09]), and DMn anticorrelated activity (e.g., right sensory cortex: W1 = -0.07 [-0.09 to -0.04]; S2 = 0.04 [0.01 to 0.06]) were broken down. SALn connectivity was nonuniformly suppressed (e.g., left parietal operculum: W1 = 0.08 [0.06 to 0.09]; S2 = 0.05 [0.02 to 0.07]). Executive control networks, auditory network, SMn, and visual network were minimally affected. Ketamine induces specific changes in connectivity within and between RSNs. Breakdown of frontoparietal DMn connectivity and DMn anticorrelation and sensory and SMn connectivity preservation are common to ketamine and propofol-induced alterations of consciousness.

Ketamine accelerates fear extinction via mTORC1 signaling.

PubMed

Girgenti, Matthew J; Ghosal, Sriparna; LoPresto, Dora; Taylor, Jane R; Duman, Ronald S

2017-04-01

Impaired fear extinction contributes to the persistence of post-traumatic stress disorder (PTSD), and can be utilized for the study of novel therapeutic agents. Glutamate plays an important role in the formation of traumatic memories, and in the pathophysiology and treatment of PTSD, highlighting several possible drug targets. Recent clinical studies demonstrate that infusion of ketamine, a glutamate NMDA receptor antagonist, rapidly and significantly reduces symptom severity in PTSD patients. In the present study, we examine the mechanisms underlying the actions of ketamine in a rodent model of fear conditioning, extinction, and renewal. Rats received ketamine or saline 24h after fear conditioning and were then subjected to extinction-training on each of the following three days. Ketamine administration enhanced extinction on the second day of training (i.e., reduced freezing behavior to cue) and produced a long-lasting reduction in freezing on exposure to cue plus context 8days later. Additionally, ketamine and extinction exposure increased levels of mTORC1 in the medial prefrontal cortex (mPFC), a region involved in the acquisition and retrieval of extinction, and infusion of the selective mTORC1 inhibitor rapamycin into the mPFC blocked the effects of ketamine on extinction. Ketamine plus extinction also increased cFos in the mPFC and administration of a glutamate-AMPA receptor antagonist blocked the effects of ketamine. These results support the hypothesis that ketamine produces long-lasting mTORC1/protein synthesis and activity dependent effects on neuronal circuits that enhance the expression of extinction and could represent a novel approach for the treatment of PTSD. Copyright © 2017 Elsevier Inc. All rights reserved.

A Randomized Controlled Trial of Intranasal Ketamine in Major Depressive Disorder

PubMed Central

Lapidus, Kyle A.B.; Levitch, Cara F.; Perez, Andrew M.; Brallier, Jess W.; Parides, Michael K.; Soleimani, Laili; Feder, Adriana; Iosifescu, Dan V.; Charney, Dennis S.; Murrough, James W.

2014-01-01

Background The N-methyl-d-aspartate glutamate receptor antagonist ketamine, delivered via an intravenous route, has shown rapid antidepressant effects in patients with treatment-resistant depression. The current study was designed to test the safety, tolerability and efficacy of intranasal ketamine in patients with depression who had failed at least one prior antidepressant trial. Methods Twenty patients with major depression were randomized and 18 completed two treatment days with intranasal ketamine hydrochloride (50 mg) or saline solution in a randomized, double-blind, crossover study. The primary efficacy outcome measure was change in depression severity 24 hours following ketamine or placebo, measured using the Montgomery-Asberg Depression Rating Scale. Secondary outcomes included persistence of benefit, changes in self-reports of depression, changes in anxiety, and proportion of responders. Potential psychotomimetic, dissociative, hemodynamic, and general adverse effects associated with ketamine were also measured. Results Patients showed significant improvement in depressive symptoms at 24 hours following ketamine compared to placebo [t=4.39, p<0.001; estimated mean MADRS score difference of 7.6 ± 3.7 (95% CI: 3.9 – 11.3)]. Eight of 18 patients (44%) met response criteria 24 hours following ketamine administration, compared to 1 of 18 (6%) following placebo (p=0.033). Intranasal ketamine was well tolerated with minimal psychotomimetic or dissociative effects and was not associated with clinically significant changes in hemodynamic parameters. Conclusions This study provides the first controlled evidence for the rapid antidepressant effects of intranasal ketamine. Treatment was associated with minimal adverse effects. If replicated, these findings may lead to novel approaches to the pharmacologic treatment of patients with major depression. Trial Registration clinicaltrials.gov identifier NCT01304147 PMID:24821196

Clinical pattern and prevalence of upper gastrointestinal toxicity in patients abusing ketamine.

PubMed

Liu, Shirley Yuk Wah; Ng, Stephen Ka Kei; Tam, Yuk Him; Yee, Samuel Chi Hang; Lai, Franco Pui Tak; Hong, Cindy Yuek Lam; Chiu, Philip Wai Yan; Ng, Enders Kwok Wai; Ng, Chi Fai

2017-09-01

Evaluations of upper gastrointestinal toxicity from ketamine abuse are uncommon. This study investigated the clinical pattern of upper gastrointestinal symptoms in patients inhaling ketamine. In a cross-sectional study of 611 consecutive patients who were seeking treatment for ketamine uropathy in a tertiary hospital setting between August 2008 and June 2016, their clinical pattern of upper gastrointestinal symptoms was evaluated and compared with a control population of 804 non-users. A total of 168 (27.5%) patients abusing ketamine (mean age 26.3 years, 58.9% female) reported the presence of upper gastrointestinal symptoms. These symptoms were significantly more prevalent in patients inhaling ketamine than in those who were not (27.5% vs 5.2%, P < 0.001). Their mean duration of ketamine abuse before symptom presentation was 5.0 ± 3.1 years. The presenting symptoms included epigastric pain (n = 155, 25.4%), recurrent vomiting (n = 48, 7.9%), anemia (n = 36, 5.9%) and gastrointestinal bleeding (n = 20, 3.3%). Uropathy symptoms were preceded by upper gastrointestinal symptoms for 4.4 ± 3.0 years in 141 (83.9%) patients. Logistic regression showed that elder age (odds ratio [OR] 1.06, P = 0.04), active abuser status (OR 1.60, P = 0.04) and longer duration of ketamine abuse (OR 1.00, P = 0.04) were independent factors associated with upper gastrointestinal toxicity. Although epigastric symptoms are unusual in the young population, upper gastrointestinal toxicity was highly prevalent in those inhaling ketamine. Enquiries about ketamine abuse are recommended when assessing young patients with epigastric symptoms. © 2017 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Evaluation of the use of midazolam as a co-induction agent with ketamine for anaesthesia in sedated ponies undergoing field castration.

PubMed

Allison, A; Robinson, R; Jolliffe, C; Taylor, P M

2018-05-01

There are limited investigations comparing ketamine to a ketamine-midazolam co-induction. To compare quality and safety of general anaesthesia induced using ketamine alone with anaesthesia co-induced using ketamine and midazolam. Randomised, double blinded, placebo controlled trial. After i.v. detomidine (20 μg/kg) thirty-eight ponies undergoing field castration received either 0.06 mg/kg (0.6 mL/50 kg) midazolam (group M) or 0.6 mL/50 kg placebo (group P) with 2.2 mg/kg ketamine i.v. for anaesthetic induction. Quality of anaesthetic induction, endotracheal intubation, surgical relaxation and recovery were scored using combinations of simple descriptive and visual analogue scales. Time of sedation, induction, start of endotracheal intubation, first movement, sternal recumbency and standing were recorded, as were time, number and total quantity of additional i.v. detomidine and ketamine injections. Cardiorespiratory variables were assessed every 5 min. Adverse effects were documented. Data were tested for normality and analysed with a mixed model ANOVA, Fisher's exact test, unpaired Students' t test and Wilcoxon Rank-sum as appropriate; P<0.05 was considered significant. Group M had better scores for induction (P = 0.005), intubation (P<0.001) and surgical relaxation (P<0.001) and required fewer additional injections of detomidine and ketamine (P = 0.04). Time (minutes) from induction to first movement (P<0.001), sternal recumbency (P =< 0.001) and standing was longer (P = 0.05) in group M. Recoveries were uneventful with no difference in quality between groups (P = 0.78). Clinical study with noninvasive monitoring undertaken in field conditions. Ketamine-midazolam co-induction compared to ketamine alone improved quality of induction, ease of intubation and muscle relaxation without impacting recovery quality. © 2017 EVJ Ltd.

Safety and Feasibility of a Ketamine Package to Support Emergency and Essential Surgery in Kenya when No Anesthetist is Available: An Analysis of 1216 Consecutive Operative Procedures.

PubMed

Burke, Thomas F; Suarez, Sebastian; Sessler, Daniel I; Senay, Ayla; Yusufali, Taha; Masaki, Charles; Guha, Moytrayee; Rogo, Debora; Jani, Pankaj; Nelson, Brett D; Rogo, Khama

2017-12-01

Lack of access to emergency and essential surgery is widespread in low- and middle-income countries. Scarce anesthesia services contribute to this unmet need. The aim of this study was to evaluate the safety and feasibility of the Every Second Matters for Emergency and Essential Surgery-Ketamine (ESM-Ketamine) package for emergency and essential procedures when no anesthetist was available. From November 2013 to September 2017, the ESM-Ketamine package was used for patients requiring emergency or life-improving surgeries in fifteen selected facilities across Kenya when no anesthetist was available. A mixed-methods approach was used to assess safety and feasibility of the ESM-Ketamine package, including demand, acceptability, and practicality. The primary outcome was ketamine-related adverse events. Key-informant interviews captured perceptions of providers, hospital administrators, and surgeons/proceduralists. Non-anesthetist mid-level providers used ESM-Ketamine for 1216 surgical procedures across the fifteen study facilities. The median ketamine dose was 2.1 mg/kg. Brief (<30 s) oxygen desaturations occurred in 39 patients (3%), and prolonged (>30 s) oxygen desaturations occurred in seven patients (0.6%). There were 157 (13%) reported cases of hallucinations and agitation which were treated with diazepam. All patients recovered uneventfully, and no ketamine-related deaths were reported. Twenty-seven key-informant interviews showed strong support for the program with four main themes: financial considerations, provision of services, staff impact, and scaling considerations. The ESM-Ketamine package appears safe and feasible and is capable of expanding access to emergency and essential surgeries in rural Kenya when no anesthetist is available.

S-Ketamine Rapidly Reverses Synaptic and Vascular Deficits of Hippocampus in Genetic Animal Model of Depression.

PubMed

Ardalan, Maryam; Wegener, Gregers; Rafati, Ali H; Nyengaard, Jens R

2017-03-01

The neurovascular plasticity of hippocampus is an important theory underlying major depression. Ketamine as a novel glutamatergic antidepressant drug can induce a rapid antidepressant effect within hours. In a mechanistic proof of this concept, we examined whether ketamine leads to an increase in synaptogenesis and vascularization within 24 hours after a single injection in a genetic rat model of depression. Flinders Sensitive Line and Flinders Resistant Line rats were given a single intraperitoneal injection of ketamine (15 mg/kg) or saline. One day later, their behavior was evaluated by a modified forced swim test. Microvessel length was evaluated with global spatial sampling and optical microscopy, whereas the number of asymmetric synapses was quantified through serial section electron microscopy by using physical disector method in the CA1.stratum radiatum area of hippocampus. The immobility time in the forced swim test among Flinders Sensitive Line rats with ketamine treatment was significantly lower compared with Flinders Sensitive Line rats without treatment. The number of nonperforated and perforated synapses was significantly higher in the Flinders Sensitive Line-ketamine vs the Flinders Sensitive Line-vehicle group; however, ketamine did not induce a significant increase in the number of shaft synapses. Additionally, total length of microvessels was significantly increased 1 day after ketamine treatment in Flinders Sensitive Line rats in the hippocampal subregions, including the CA1.stratum radiatum. Our findings indicate that hippocampal vascularization and synaptogenesis is co-regulated rapidly after ketamine, and microvascular elongation may be a supportive factor for synaptic plasticity and neuronal activity. These findings go hand-in-hand with the behavioral observations, where ketamine acts as a potent antidepressant. © The Author 2016. Published by Oxford University Press on behalf of CINP.

Apoptosis-related genes induced in response to ketamine during early life stages of zebrafish.

PubMed

Félix, Luís M; Serafim, Cindy; Valentim, Ana M; Antunes, Luís M; Matos, Manuela; Coimbra, Ana M

2017-09-05

Increasing evidence supports that ketamine, a widely used anaesthetic, potentiates apoptosis during development through the mitochondrial pathway of apoptosis. Defects in the apoptotic machinery can cause or contribute to the developmental abnormalities previously described in ketamine-exposed zebrafish. The involvement of the apoptotic machinery in ketamine-induced teratogenicity was addressed by assessing the apoptotic signals at 8 and 24 hpf following 20min exposure to ketamine at three stages of early zebrafish embryo development (256 cell, 50% epiboly and 1-4 somites stages). Exposure at the 256-cell stage to ketamine induced an up-regulation of casp8 and pcna at 8 hpf while changes in pcna at the mRNA level were observed at 24 hpf. After the 50% epiboly stage exposure, the mRNA levels of casp9 were increased at 8 and 24 hpf while aifm1 was affected at 24 hpf. Both tp53 and pcna expressions were increased at 8 hpf. After exposure during the 1-4 somites stage, no meaningful changes on transcript levels were observed. The distribution of apoptotic cells and the caspase-like enzymatic activities of caspase-3 and -9 were not affected by ketamine exposure. It is proposed that ketamine exposure at the 256-cell stage induced a cooperative mechanism between proliferation and cellular death while following exposure at the 50% epiboly, a p53-dependent and -independent caspase activation may occur. Finally, at the 1-4 somites stage, the defence mechanisms are already fully in place to protect against ketamine-insult. Thus, ketamine teratogenicity seems to be dependent on the functional mechanisms present in each developmental stage. Copyright © 2017 Elsevier B.V. All rights reserved.

Ketamine for chronic pain: risks and benefits.

PubMed

Niesters, Marieke; Martini, Christian; Dahan, Albert

2014-02-01

The anaesthetic ketamine is used to treat various chronic pain syndromes, especially those that have a neuropathic component. Low dose ketamine produces strong analgesia in neuropathic pain states, presumably by inhibition of the N-methyl-D-aspartate receptor although other mechanisms are possibly involved, including enhancement of descending inhibition and anti-inflammatory effects at central sites. Current data on short term infusions indicate that ketamine produces potent analgesia during administration only, while three studies on the effect of prolonged infusion (4-14 days) show long-term analgesic effects up to 3 months following infusion. The side effects of ketamine noted in clinical studies include psychedelic symptoms (hallucinations, memory defects, panic attacks), nausea/vomiting, somnolence, cardiovascular stimulation and, in a minority of patients, hepatoxicity. The recreational use of ketamine is increasing and comes with a variety of additional risks ranging from bladder and renal complications to persistent psychotypical behaviour and memory defects. Blind extrapolation of these risks to clinical patients is difficult because of the variable, high and recurrent exposure to the drug in ketamine abusers and the high frequency of abuse of other illicit substances in this population. In clinical settings, ketamine is well tolerated, especially when benzodiazepines are used to tame the psychotropic side effects. Irrespective, close monitoring of patients receiving ketamine is mandatory, particularly aimed at CNS, haemodynamic, renal and hepatic symptoms as well as abuse. Further research is required to assess whether the benefits outweigh the risks and costs. Until definite proof is obtained ketamine administration should be restricted to patients with therapy-resistant severe neuropathic pain. © 2013 The Authors. British Journal of Clinical Pharmacology © 2013 The British Pharmacological Society.

Inhibition of spinal astrocytic c-Jun N-terminal kinase (JNK) activation correlates with the analgesic effects of ketamine in neuropathic pain

PubMed Central

2011-01-01

Background We have previously reported that inhibition of astrocytic activation contributes to the analgesic effects of intrathecal ketamine on spinal nerve ligation (SNL)-induced neuropathic pain. However, the underlying mechanisms are still unclear. c-Jun N-terminal kinase (JNK), a member of mitogen-activated protein kinase (MAPK) family, has been reported to be critical for spinal astrocytic activation and neuropathic pain development after SNL. Ketamine can decrease lipopolysaccharide (LPS)-induced phosphorylated JNK (pJNK) expression and could thus exert its anti-inflammatory effect. We hypothesized that inhibition of astrocytic JNK activation might be involved in the suppressive effect of ketamine on SNL-induced spinal astrocytic activation. Methods Immunofluorescence histochemical staining was used to detect SNL-induced spinal pJNK expression and localization. The effects of ketamine on SNL-induced mechanical allodynia were confirmed by behavioral testing. Immunofluorescence histochemistry and Western blot were used to quantify the SNL-induced spinal pJNK expression after ketamine administration. Results The present study showed that SNL induced ipsilateral pJNK up-regulation in astrocytes but not microglia or neurons within the spinal dorsal horn. Intrathecal ketamine relieved SNL-induced mechanical allodynia without interfering with motor performance. Additionally, intrathecal administration of ketamine attenuated SNL-induced spinal astrocytic JNK activation in a dose-dependent manner, but not JNK protein expression. Conclusions The present results suggest that inhibition of JNK activation may be involved in the suppressive effects of ketamine on SNL-induced spinal astrocyte activation. Therefore, inhibition of spinal JNK activation may be involved in the analgesic effects of ketamine on SNL-induced neuropathic pain. PMID:21255465

Effect of ketamine on endogenous pain modulation in healthy volunteers.

PubMed

Niesters, Marieke; Dahan, Albert; Swartjes, Maarten; Noppers, Ingeborg; Fillingim, Roger B; Aarts, Leon; Sarton, Elise Y

2011-03-01

Inhibitory and facilitatory descending pathways, originating at higher central nervous system sites, modulate activity of dorsal horn nociceptive neurons, and thereby influence pain perception. Dysfunction of inhibitory pain pathways or a shift in the balance between pain facilitation and pain inhibition has been associated with the development of chronic pain. The N-methyl-d-aspartate receptor antagonist ketamine has a prolonged analgesic effect in chronic pain patients. This effect is due to desensitization of sensitized N-methyl-d-aspartate receptors. Additionally, ketamine may modulate or enhance endogenous inhibitory control of pain perception. Diffuse noxious inhibitory control (DNIC) and offset analgesia (OA) are 2 mechanisms involved in descending inhibition. The present study investigates the effect of a ketamine infusion on subsequent DNIC and OA responses to determine whether ketamine has an influence on descending pain control. Ten healthy subjects (4 men/6 women) received a 1-hour placebo or S(+)-ketamine (40mg per 70kg) infusion on 2 separate occasions in random order. Upon the termination of the infusion, DNIC and OA responses were obtained. After placebo treatment, significant descending inhibition of pain responses was present for DNIC and OA. In contrast, after ketamine infusion, no DNIC was observed, but rather a significant facilitatory pain response (P<0.01); the OA response remained unchanged. These findings suggest that the balance between pain inhibition and pain facilitation was shifted by ketamine towards pain facilitation. The absence of an effect of ketamine on OA indicates differences in the mechanisms and neurotransmitter influences between OA and DNIC. Diffuse noxious inhibitory control responses following a 1-hour low-dose ketamine treatment displayed facilitation of pain in response to experimental noxious thermal stimulation. Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

GLYX-13 (rapastinel) ameliorates subchronic phencyclidine- and ketamine-induced declarative memory deficits in mice

PubMed Central

Rajagopal, Lakshmi; Burgdorf, Jeffrey S.; Moskal, Joseph R.; Meltzer, Herbert Y.

2016-01-01

GLYX-13 (rapastinel), a tetrapeptide (Thr-Pro-Pro-Thr-amide), has been reported to have fast acting antidepressant properties in man based upon its N-methyl-d-aspartate receptor (NMDAR) glycine site functional partial agonism. Ketamine, a non-competitive NMDAR antagonist, also reported to have fast acting antidepressant properties, produces cognitive impairment in rodents and man, whereas rapastinel has been reported to have cognitive enhancing properties in rodents, without impairing cognition in man, albeit clinical testing has been limited. The goal of this study was to compare the cognitive impairing effects of rapastinel and ketamine in novel object recognition (NOR), a measure of declarative memory, in male C57BL/6J mice treated with phencyclidine (PCP), another NMDAR noncompetitive antagonist known to severely impair cognition, in both rodents and man. C57BL/6J mice given a single dose or subchronic ketamine (30 mg/kg. i.p.) showed acute or persistent deficits in NOR, respectively. Acute i.v. rapastinel (1.0 mg/kg), did not induce NOR deficit. Pre-treatment with rapastinel significantly prevented acute ketamine-induced NOR deficit. Rapastinel (1.0 mg/kg, but not 0.3 mg/kg, iv) significantly reversed both subchronic ketamine- and subchronic PCP-induced NOR deficits. Rapastinel also potentiated the atypical antipsychotic drug with antidepressant properties, lurasidone, to restore NOR in subchronic ketamine-treated mice. These findings indicate that rapastinel, unlike ketamine, does not induce a declarative memory deficit in mice, and can prevent or reverse the ketamine-induced NOR deficit. Further study is required to determine if these differences translate during clinical use of ketamine and rapastinel as fast acting antidepressant drugs and if rapastinel could have non-ionotropic effects as an add-on therapy with antipsychotic/antidepressant medications. PMID:26632337

5-Hydroxytryptamine-Independent Antidepressant Actions of (R)-Ketamine in a Chronic Social Defeat Stress Model.

PubMed

Zhang, Kai; Dong, Chao; Fujita, Yuko; Fujita, Atsuhiro; Hashimoto, Kenji

2018-02-01

Previous reports suggest that 5-hydroxytryptamine might play a role in the antidepressant actions of (R,S)-ketamine. However, its role in the antidepressant actions of (R)-ketamine, which is more potent than (S)-ketamine, is unknown. This study was conducted to examine whether 5-hydroxytryptamine depletion affects the antidepressant actions of (R)-ketamine in a chronic social defeat stress model. An inhibitor of 5-hydroxytryptamine synthesis, para-chlorophenylalanine methyl ester hydrochloride (300 mg/kg, twice daily for 3 consecutive days), or vehicle was administered to control and chronic social defeat stress-susceptible mice. Levels of 5-hydroxytryptamine and its metabolite, 5-hydroxyindoleacetic acid, in mouse brain regions were measured using high-performance liquid chromatography. Furthermore, antidepressant effects of (R)-ketamine (10 mg/kg) in the vehicle- and para-chlorophenylalanine methyl ester hydrochloride-treated susceptible mice were assessed using tail suspension test and 1% sucrose preference test. para-Chlorophenylalanine methyl ester hydrochloride treatment caused marked reductions of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in the brain regions of control and chronic social defeat stress susceptible mice. In the tail suspension test, (R)-ketamine significantly attenuated the increased immobility time in the chronic social defeat stress-susceptible mice with or without 5-hydroxytryptamine depletion. In the sucrose preference test (2 and 5 days after a single dose), (R)-ketamine significantly enhanced reduced sucrose consumption in the chronic social defeat stress-susceptible mice with or without 5-hydroxytryptamine depletion. These findings show that 5-hydroxytryptamine depletion did not affect the antidepressant effects of (R)-ketamine in a chronic social defeat stress model. Therefore, it is unlikely that 5-hydroxytryptamine plays a major role in the antidepressant actions of (R)-ketamine. © The Author 2017. Published by Oxford University Press on behalf of CINP.

Synergistic interaction between ketamine and magnesium in lowering body temperature in rats.

PubMed

Vučković, Sonja M; Savić Vujović, Katarina R; Srebro, Dragana P; Medić, Branislava M; Vučetić, Cedomir S; Prostran, Milan Š; Prostran, Milica Š

2014-03-29

A large body of evidence supports the existence of an endogenous glutamate system that tonically modulates body temperature via N-methyl-d-aspartate (NMDA) receptors. Ketamine and magnesium, both NMDA receptor antagonists, are known for their anesthetic, analgesic and anti-shivering properties. This study is aimed at evaluating the effects of ketamine and magnesium sulfate on body temperature in rats, and to determine the type of interaction between them. The body temperature was measured by insertion of a thermometer probe 5cm into the colon of unrestrained male Wistar rats (200-250g). Magnesium sulfate (5 and 60mg/kg, sc) showed influence neither on baseline, nor on morphine-evoked hyperthermic response. Subanesthetic doses of ketamine (5-30mg/kg, ip) given alone, produced significant dose-dependent reduction in both baseline colonic temperature and morphine-induced hyperthermia. Analysis of the log dose-response curves for the effects of ketamine and ketamine-magnesium sulfate combination on the baseline body temperature revealed synergistic interaction, and about 5.3 fold reduction in dosage of ketamine when the drugs were applied in fixed ratio (1:1) combinations. In addition, fixed low dose of magnesium sulfate (5mg/kg, sc) enhanced the temperature lowering effect of ketamine (1.25-10mg/kg, ip) on baseline body temperature and morphine-induced hyperthermia by factors of about 2.5 and 5.3, respectively. This study is the first to demonstrate the synergistic interaction between magnesium sulfate and ketamine in a whole animal study and its statistical confirmation. It is possible that the synergy between ketamine and magnesium may have clinical relevance. Copyright © 2014 Elsevier Inc. All rights reserved.

Reduction of dopamine D2/3 receptor binding in the striatum after a single administration of esketamine, but not R-ketamine: a PET study in conscious monkeys.

PubMed

Hashimoto, Kenji; Kakiuchi, Takeharu; Ohba, Hiroyuki; Nishiyama, Shingo; Tsukada, Hideo

2017-03-01

R-ketamine appears to be a potent, long-lasting and safer antidepressant, relative to esketamine (S-ketamine), since it might be free of psychotomimetic side effects. Using [ 11 C]raclopride and positron emission tomography (PET), we investigated whether esketamine and R-ketamine can affect dopamine D 2/3 receptor binding in the conscious monkey brain. A single infusion of esketamine (0.5 mg/kg), but not R-ketamine (0.5 mg/kg), caused a reduction of binding availability of dopamine D 2/3 receptor in the monkey striatum. This study suggests that unlike to R-ketamine, esketamine can cause dopamine release in the striatum, and that its release might be associated with psychotomimetic effects of esketamine.

Ketamine use among regular tobacco and alcohol users as revealed by respondent driven sampling in Taipei: prevalence, expectancy, and users’ risky decision making

PubMed Central

Chen, Wei J.; Ting, Te-Tien; Chang, Chao-Ming; Liu, Ying-Chun; Chen, Chuan-Yu

2014-01-01

The popularity of ketamine for recreational use among young people began to increase, particularly in Asia, in 2000. To gain more knowledge about the use of ketamine among high risk individuals, a respondent-driven sampling (RDS) was implemented among regular alcohol and tobacco users in the Taipei metropolitan area from 2007 to 2010. The sampling was initiated in three different settings (i.e., two in the community and one in a clinic) to recruit seed individuals. Each participant was asked to refer one to five friends known to be regular tobacco smokers and alcohol drinkers to participate in the present study. Incentives were offered differentially upon the completion of an interview and successful referral. Information pertaining to drug use experience was collected by an audio computer-assisted self-interview instrument. Software built for RDS analyses was used for data analyses. Of the 1,115 subjects recruited, about 11.7% of the RDS respondents reported ever having used ketamine. Positive expectancy of ketamine use was positively associated with ketamine use; in contrast, negative expectancy inversely associated with ketamine use. Decision-making characteristics as measured on the Iowa Gambling Task using reinforcement learning models revealed that ketamine users learned less from the most recent event than both tobacco- and drug-naïve controls and regular tobacco and alcohol users. These findings about ketamine use among young people have implications for its prevention and intervention. PMID:25264412

Long-term effect of sub-anesthetic ketamine in reducing L-DOPA-induced dyskinesias in a preclinical model.

PubMed

Bartlett, Mitchell J; Joseph, Ria M; LePoidevin, Lindsey M; Parent, Kate L; Laude, Nicholas D; Lazarus, Levi B; Heien, Michael L; Estevez, Miguel; Sherman, Scott J; Falk, Torsten

2016-01-26

Low-dose sub-anesthetic ketamine infusion treatment has led to a long-term reduction of treatment-resistant depression and posttraumatic stress disorder (PTSD) symptom severity, as well as reduction of chronic pain states, including migraine headaches. Ketamine also is known to change oscillatory electric brain activity. One commonality between migraine headaches, depression, PTSD, Parkinson's disease (PD) and l-DOPA-induced dyskinesias (LID) is hypersynchrony of electric activity in the brain, including the basal ganglia. Therefore, we investigated the use of low-dose sub-anesthetic ketamine in the treatment of LID. In a preclinical rodent model of LID, ketamine (5-20mg/kg) led to long-term dose-dependent reduction of abnormal involuntary movements, only when low-dose ketamine was given for 10h continuously (5× i.p. injections two hours apart) and not after a single acute low-dose ketamine i.p. injection. Pharmacokinetic analysis of plasma levels showed ketamine and its major metabolites were not detectable any more at time points when a lasting anti-dyskinetic effect was seen, indicating a plastic change in the brain. This novel use of low-dose sub-anesthetic ketamine infusion could lead to fast clinical translation, and since depression and comorbid pain states are critical problems for many PD patients could open up the road to a new dual therapy for patients with LID. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Levo-tetrahydropalmatine inhibits the acquisition of ketamine-induced conditioned place preference by regulating the expression of ERK and CREB phosphorylation in rats.

PubMed

Du, Yan; Du, Li; Cao, Jie; Hölscher, Christian; Feng, Yongming; Su, Hongliang; Wang, Yujin; Yun, Ke-Ming

2017-01-15

Levo-tetrahydropalmatine (l-THP) is an alkaloid purified from the Chinese herbs Corydalis and Stephania and has been used in many traditional Chinese herbal preparations for its sedative, analgesic and hypnotic properties. Previous studies demonstrated that l-THP has antagonistic activity on dopamine receptors; thus, it may have potential therapeutic effects on drug abuse. However, whether l-THP affects ketamine-induced conditioned place preference (CPP) remains unclear. Therefore, the present study was designed to evaluate the effects of l-THP on the rewarding behavior of ketamine through CPP. Results revealed that ketamine (5, 10 and 15mg/kg) induced CPP in rats. Furthermore, Ketamine (10mg/kg) promoted the phosphorylation of extracellular-regulated kinase (ERK) and cAMP responsive element binding protein (CREB) in the hippocampus (Hip) and caudate putamen (CPu), but not in the prefrontal cortex (PFc). l-THP (20mg/kg) co-administered with ketamine during conditioning inhibited the acquisition of ketamine-induced CPP in rats. Furthermore, l-THP (20mg/kg) prevented the enhanced phosphorylation of ERK and CREB in CPu and Hip. These results suggest that l-THP has potential therapeutic effects on ketamine-induced CPP. The underlying molecular mechanism may be related to its inhibitory effect on ERK and CREB phosphorylation in Hip and CPu. The present data supports the potential use of l-THP for the treatment of ketamine addiction. Copyright © 2016 Elsevier B.V. All rights reserved.

Ketamine for Treatment-Resistant Unipolar Depression

PubMed Central

Mathew, Sanjay J.; Shah, Asim; Lapidus, Kyle; Clark, Crystal; Jarun, Noor; Ostermeyer, Britta; Murrough, James W.

2013-01-01

Currently available drugs for unipolar major depressive disorder (MDD), which target monoaminergic systems, have a delayed onset of action and significant limitations in efficacy. Antidepressants with primary pharmacological targets outside the monoamine system may offer the potential for more rapid activity with improved therapeutic benefit. The glutamate system has been scrutinized as a target for antidepressant drug discovery. The purpose of this article is to review emerging literature on the potential rapid-onset antidepressant properties of the glutamate NMDA receptor antagonist ketamine, an established anaesthetic agent. The pharmacology of ketamine and its enantiomer S-ketamine is reviewed, followed by examples of its clinical application in chronic, refractory pain conditions, which are commonly co-morbid with depression. The first generation of studies in patients with treatment-resistant depression (TRD) reported the safety and acute efficacy of a single subanaesthetic dose (0.5 mg/kg) of intravenous ketamine. A second generation of ketamine studies is focused on testing alternate routes of drug delivery, identifying methods to prevent relapse following resolution of depressive symptoms and understanding the neural basis for the putative antidepressant actions of ketamine. In addition to traditional depression rating endpoints, ongoing research is examining the impact of ketamine on neurocognition. Although the first clinical report in MDD was published in 2000, there is a paucity of adequately controlled double-blind trials, and limited clinical experience outside of research settings. Given the potential risks of ketamine, safety considerations will ultimately determine whether this old drug is successfully repositioned as a new therapy for TRD. PMID:22303887

Efficacy of ketamine in improving pain after tonsillectomy in children: meta-analysis.

PubMed

Cho, Hye Kyung; Kim, Kyu Won; Jeong, Yeon Min; Lee, Ho Seok; Lee, Yeon Ji; Hwang, Se Hwan

2014-01-01

The goal of this meta-analysis study was to perform a systematic review of the literature on the effects of ketamine on postoperative pain following tonsillectomy and adverse effects in children. Two authors independently searched three databases (MEDLINE, SCOPUS, Cochrane) from their inception of article collection to February 2014. Studies that compared preoperative ketamine administration (ketamine groups) with no treatment (control group) or opioid administration (opioid group) where the outcomes of interest were postoperative pain intensity, rescue analgesic consumption, or adverse effects (sedation, nausea and vomiting, bad dream, worsening sleep pattern, and hallucination) 0-24 hours after leaving the operation room were included in the analysis. The pain score reported by the physician during first 4 hours and need for analgesics during 24 hours postoperatively was significantly decreased in the ketamine group versus control group and was similar with the opioid group. In addition, there was no significant difference between ketamine and control groups for adverse effects during 24 hours postoperatively. In the subgroup analyses (systemic and local administration) regarding pain related measurements, peritonsillar infiltration of ketamine was more effective in reducing the postoperative pain severity and need for analgesics. Preoperative administration of ketamine systemically or locally could provide pain relief without side-effects in children undergoing tonsillectomy. However, considering the insufficient evaluation of efficacy of ketamine according to the administration methods and high heterogeneity in some parameters, further clinical trials with robust research methodology should be conducted to confirm the results of this study.

Relationship of serum levels of TNF-α, IL-6 and IL-18 and schizophrenia-like symptoms in chronic ketamine abusers

PubMed Central

Fan, Ni; Luo, Yayan; Xu, Ke; Zhang, Minling; Ke, Xiaoyin; Huang, Xini; Ding, Yi; Wang, Daping; Ning, Yuping; Deng, Xuefeng; He, Hongbo

2016-01-01

Objective Exposing to NMDAR receptor antagonists, such as ketamine, produces schizophrenia-like symptoms in humans and deteriorates symptoms in schizophrenia patients. Meanwhile, schizophrenia is associated with alterations of cytokines in the immune system. This study aims to examine the serum TNF-α, IL-6 and IL-18 levels in chronic human ketamine users as compared to healthy subjects. The correlations between the serum cytokines levels with the demographic, ketamine use characteristics and psychiatric symptoms were also assessed. Methods 155 subjects who fulfilled the criteria of ketamine dependence and 80 healthy control subjects were recruited. Serum TNF-α, IL-6 and IL-18 levels were measured using an enzyme-linked immunosorbent assay (ELISA). The psychiatric symptoms of the ketamine abusers were assessed using the Positive and Negative Syndrome Scale (PANSS). Results Serum IL-6 and IL-18 levels were significantly higher, while serum TNF-α level was significantly lower among ketamine users than among healthy controls (p < 0.05). Serum TNF-α levels showed a significant negative association with PANSS total score (r = −0.210, p < 0.01) and negative subscore (r = −0.300, p < 0.01). No significant association was found between PANSS score and serum levels of IL-6 and IL-18. Conclusions Serum levels of TNF-α, IL-6 and IL-18 were altered in chronic ketamine abusers which may play a role in schizophrenia-like symptoms in chronic ketamine abusers. PMID:26589393

Nitric oxide involvement in the antidepressant-like effect of ketamine in the Flinders sensitive line rat model of depression.

PubMed

Liebenberg, Nico; Joca, Sâmia; Wegener, Gregers

2015-04-01

We investigated whether the nitric oxide (NO) precursor, L-arginine, can prevent the antidepressant-like action of the fast-acting antidepressant, ketamine, in a genetic rat model of depression, and/or induce changes in the glutamate (Glu)/N-methyl-D-aspartate receptor (NMDAR)/NO/cyclic guanosine monophosphate (cGMP) signalling pathway. Hereby it was evaluated whether the NO signalling system is involved in the antidepressant mechanism of ketamine. Flinders sensitive line (FSL) rats received single i.p. injections of ketamine (15 mg/kg) with/without pre-treatment (30 min prior) with L-arginine (500 mg/kg). Depression-like behaviour was assessed in the forced swim test (FST) in terms of immobility, and the activation state of the Glu/NMDAR/NO/cGMP pathway was evaluated ex vivo in the frontal cortex and hippocampus regions in terms of total constitutive NOS (cNOS) activity and cGMP concentration. L-Arginine pre-treatment prevented the antidepressant-like effect of ketamine in the FST, as well as a ketamine-induced increase in cGMP levels in the frontal cortex and hippocampus of FSL rats. Ketamine reduced cNOS activity only in the hippocampus, and this effect was not reversed by L-arginine. Both the behavioural and molecular results from this study indicate an involvement for the NO signalling pathway in the antidepressant action of ketamine. Although not easily interpretable, these findings broaden our knowledge of effects of ketamine on the NO system.

Some considerations of the tolerability of ketamine for ECT anesthesia: a case series and review of the literature.

PubMed

Rasmussen, Keith G; Ritter, Matthew J

2014-12-01

Most anesthetic agents used for electroconvulsive therapy (ECT) have few intrinsic adverse effects. Ketamine, however, is well known to be associated with a variety of adverse effects including nausea, dizziness, and psychotomimetic phenomena. Over the past several decades, there have been numerous reports on the use of ketamine for ECT anesthesia, with varied assessments on how prominent these adverse effects are in the ECT situation. Ketamine has received a resurgence of interest as an ECT anesthetic of late owing to its established independent antidepressant effects and to theoretical reasons why it might lessen the cognitive adverse effects of ECT. In this case series, the author reviews the experience with 14 patients who had undergone ECT who were switched to ketamine as anesthetic from methohexital at the preference of the treating anesthesiologist. All 14 patients spontaneously reported a strong preference not to be given ketamine again due to bothersome adverse effects. The latter consisted of either vestibular-type symptoms (nausea/vomiting, dizziness, and vertigo) or psychotomimetic effects (dissociative phenomena). It is concluded that ketamine is not free of adverse effects when used as an ECT anesthetic. Electroconvulsive therapy clinicians should be vigilant about assessing for these effects when ketamine is used, and consideration should be given to using a benzodiazepine such as diazepam or midazolam at seizure termination when ketamine anesthesia is used to prevent bothersome adverse effects seen upon awakening.

The effect of ketamine on the consolidation and extinction of contextual fear memory

PubMed Central

Thomas, Kerrie L; Hall, Jeremy

2018-01-01

Ketamine, principally an antagonist of N-methyl-ᴅ-aspartate receptors, induces schizophrenia-like symptoms in adult humans, warranting its use in the investigation of psychosis-related phenotypes in animal models. Genomic studies further implicate N-methyl-ᴅ-aspartate receptor-mediated processes in schizophrenia pathology, together with more broadly-defined synaptic plasticity and associative learning processes. Strong pathophysiological links have been demonstrated between fear learning and psychiatric disorders such as schizophrenia. To further investigate the impact of ketamine on associative fear learning, we studied the effects of pre- and post-training ketamine on the consolidation and extinction of contextual fear memory in rats. Administration of 25 mg/kg ketamine prior to fear conditioning did not affect consolidation when potentially confounding effects of state dependency were controlled for. Pre-training ketamine (25 mg/kg) impaired the extinction of the conditioned fear response, which was mirrored with the use of a lower dose (8 mg/kg). Post-training ketamine (25 mg/kg) had no effect on the consolidation or extinction of conditioned fear. These observations implicate processes relating to the extinction of contextual fear memory in the manifestation of ketamine-induced phenotypes, and are consistent with existing hypotheses surrounding abnormal associative learning in schizophrenia. PMID:29338491

The effects of a subpsychotic dose of ketamine on recognition and source memory for agency: implications for pharmacological modelling of core symptoms of schizophrenia.

PubMed

Honey, Garry D; O'loughlin, Chris; Turner, Danielle C; Pomarol-Clotet, Edith; Corlett, Philip R; Fletcher, Paul C

2006-02-01

Ketamine is increasingly used to model the cognitive deficits and symptoms of schizophrenia. We investigated the extent to which ketamine administration in healthy volunteers reproduces the deficits in episodic recognition memory and agency source monitoring reported in schizophrenia. Intravenous infusions of placebo or 100 ng/ml ketamine were administered to 12 healthy volunteers in a double-blind, placebo-controlled, randomized, within-subjects study. In response to presented words, the subject or experimenter performed a deep or shallow encoding task, providing a 2(drug) x 2(depth of processing) x 2(agency) factorial design. At test, subjects discriminated old/new words, and recalled the sources (task and agent). Data were analyzed using multinomial modelling to identify item recognition, source memory for agency and task, and guessing biases. Under ketamine, item recognition and cued recall of deeply encoded items were impaired, replicating previous findings. In contrast to schizophrenia, there was a reduced tendency to externalize agency source guessing biases under ketamine. While the recognition memory deficit observed with ketamine is consistent with previous work and with schizophrenia, the changes in source memory differ from those reported in schizophrenic patients. This difference may account for the pattern of psychopathology induced by ketamine.

Ketamine-dependent neuronal activation in healthy volunteers.

PubMed

Höflich, Anna; Hahn, Andreas; Küblböck, Martin; Kranz, Georg S; Vanicek, Thomas; Ganger, Sebastian; Spies, Marie; Windischberger, Christian; Kasper, Siegfried; Winkler, Dietmar; Lanzenberger, Rupert

2017-04-01

Over the last years, a number of studies have been conducted to clarify the neurobiological correlates of ketamine application. However, comprehensive information regarding the influence of ketamine on cortical activity is still lacking. Using resting-state functional MRI and integrating pharmacokinetic information, a double-blind, randomized, placebo-controlled, crossover study was performed to determine the effects of ketamine on neuronal activation. During a 55 min resting-state fMRI scan, esketamine (Ketanest S ® ) was administered intravenously to 35 healthy volunteers. Neural activation as indicated by the BOLD signal using the pharmacokinetic curve of ketamine plasma levels as a regressor was computed. Compared with placebo, ketamine-dependent increases of neural activation were observed in the midcingulate cortex, the dorsal part of the anterior cingulate cortex, the insula bilaterally, and the thalamus (t values ranging between 5.95-9.78, p < 0.05; FWE-corrected). A significant decrease of neural activation in the ketamine condition compared to placebo was found in a cluster within the subgenual/subcallosal part of the anterior cingulate cortex, the orbitofrontal cortex and the gyrus rectus (t = 7.81, p < 0.05, FWE-corrected). Using an approach combining pharmacological and fMRI data, important information about the neurobiological correlates of the clinical antidepressant effects of ketamine could be revealed.

Role of Ketamine in Acute Postoperative Pain Management: A Narrative Review

PubMed Central

Radvansky, Brian M.; Shah, Khushbu; Parikh, Anant; Sifonios, Anthony N.; Eloy, Jean D.

2015-01-01

Objectives. The objective of this narrative review was to examine the usage of ketamine as a postoperative analgesic agent across a wide variety of surgeries. Design. A literature search was performed using the phrases “ketamine” and “postoperative pain.” The authors analyzed the studies that involved testing ketamine's effectiveness at controlling postoperative pain. Effectiveness was assessed through various outcomes such as the amount of opiate consumption, visual analog scale (VAS) pain scores, and persistent postoperative pain at long-term follow-up. Results. While many different administration protocols were evaluated, delivering ketamine both as a pre- or perioperative bolus and postoperative infusion for up to 48 hours appeared to be the most effective. These effects are dose-dependent. However, a number of studies analyzed showed no benefit in using ketamine versus placebo for controlling postoperative pain. While ketamine is a safe and well-tolerated drug, it does have adverse effects, and there are concerns for possible neurotoxicity and effects on memory. Conclusions. In a number of limited situations, ketamine has shown some efficacy in controlling postoperative pain and decreasing opioid consumption. More randomized controlled trials are necessary to determine the surgical procedures and administrations (i.e., intravenous, epidural) that ketamine is best suited for. PMID:26495312

Evaluating the Use of Ketamine for Pain Control With Sickle Cell Crisis in Pregnancy: A Report of 2 Cases.

PubMed

Gimovsky, Alexis C; Fritton, Kate; Viscusi, Eugene; Roman, Amanda

2018-01-01

Sickle cell crises occur frequently during pregnancy and are difficult to treat, even with high-dose opioids. Analgesia with ketamine has been suggested as an alternative, but its use during pregnancy is underreported. Two pregnant patients with uncontrolled sickle cell pain were treated with ketamine. Patient A reported no decrease in her pain, but her opioid requirements decreased. Patient B's pain resolved during ketamine administration. No serious maternal or neonatal adverse effects occurred. Ketamine may be considered as an adjunct analgesic in pregnant patients with sickle cell pain, although prospective clinical data are needed to fully assess its efficacy.

A Case Report: Subanesthetic Ketamine Infusion for Treatment of Cancer-Related Pain Produces Urinary Urge Incontinence.

PubMed

Vickers, Barbara A; Lee, Wayne; Hunsberger, Joann

2017-05-01

Oncology patients undergoing treatment can experience substantial pain related to their disease or prescribed therapy. Ketamine infusions at subanesthetic doses have been used at our institution to supplement the pain management regimens of 262 patients. We present 2 cases in which young adult patients being treated with subanesthetic ketamine for cancer-related pain experienced urinary urgency and incontinence after initiation or increase of the ketamine infusion. This adverse effect has not been reported previously at this dosing range. These case reports suggest that subanesthetic ketamine infusions may cause side effects that previously have been reported only at anesthetic or abuse doses.

Suppressed neural complexity during ketamine- and propofol-induced unconsciousness.

PubMed

Wang, Jisung; Noh, Gyu-Jeong; Choi, Byung-Moon; Ku, Seung-Woo; Joo, Pangyu; Jung, Woo-Sung; Kim, Seunghwan; Lee, Heonsoo

2017-07-13

Ketamine and propofol have distinctively different molecular mechanisms of action and neurophysiological features, although both induce loss of consciousness. Therefore, identifying a common feature of ketamine- and propofol-induced unconsciousness would provide insight into the underlying mechanism of losing consciousness. In this study we search for a common feature by applying the concept of type-II complexity, and argue that neural complexity is essential for a brain to maintain consciousness. To test this hypothesis, we show that complexity is suppressed during loss of consciousness induced by ketamine or propofol. We analyzed the randomness (type-I complexity) and complexity (type-II complexity) of electroencephalogram (EEG) signals before and after bolus injection of ketamine or propofol. For the analysis, we use Mean Information Gain (MIG) and Fluctuation Complexity (FC), which are information-theory-based measures that quantify disorder and complexity of dynamics respectively. Both ketamine and propofol reduced the complexity of the EEG signal, but ketamine increased the randomness of the signal and propofol decreased it. The finding supports our claim and suggests EEG complexity as a candidate for a consciousness indicator. Copyright © 2017 Elsevier B.V. All rights reserved.

Oral ketamine for sickle cell crisis pain refractory to opioids.

PubMed

Jennings, Cara A; Bobb, Barton T; Noreika, Danielle M; Coyne, Patrick J

2013-06-01

There is literature demonstrating that the N-methyl-d-aspartate (NMDA) receptor antagonist ketamine has analgesic properties that can be used as an adjuvant to opiates for pain relief in multiple various conditions and pain states. However, there is a lack of published information on ketamine used in persons with sickle cell disease in acute pain crises. The Virginia Commonwealth University Palliative Care team was consulted on a 38-year-old African American female with sickle cell thalassemia in severe acute pain crisis overlying chronic pain related to her disease. Pain control was unable to be achieved with escalating doses of opiates and other adjuvant medications. The patient responded well to an intravenous test dose of ketamine and was subsequently placed on an oral regimen of ketamine in addition to opiates. In the 24-hour period following ketamine initiation, the patient's pain was able to be controlled on decreased amounts of opiates. She was eventually transitioned to an oral opiate and ketamine regimen, which allowed her to be discharged home with pain levels close to her baseline and the ability to function and perform all activities of daily living.

Ketamine, sleep, and depression: current status and new questions.

PubMed

Duncan, Wallace C; Zarate, Carlos A

2013-09-01

Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has well-described rapid antidepressant effects in clinical studies of individuals with treatment-resistant major depressive disorder (MDD). Preclinical studies investigating the effects of ketamine on brain-derived neurotrophic factor (BDNF) and on sleep slow wave activity (SWA) support its use as a prototype for investigating the neuroplastic mechanisms presumably involved in the mechanism of rapidly acting antidepressants. This review discusses human EEG slow wave sleep parameters and plasma BDNF as central and peripheral surrogate markers of plasticity, and their use in assessing ketamine's effects. Acutely, ketamine elevates BDNF levels, as well as early night SWA and high-amplitude slow waves; each of these measures correlates with change in mood in depressed patients who respond to ketamine. The slow wave effects are limited to the first night post-infusion, suggesting that their increase is part of an early cascade of events triggering improved mood. Increased total sleep and decreased waking occur during the first and second night post infusion, suggesting that these measures are associated with the enduring treatment response observed with ketamine.

Clinically favourable effects of ketamine as an anaesthetic for electroconvulsive therapy: a retrospective study.

PubMed

Kranaster, Laura; Kammerer-Ciernioch, Jutta; Hoyer, Carolin; Sartorius, Alexander

2011-12-01

In a retrospective chart review, we examined the effects of ketamine, an N-methyl-d-aspartate (NMDA) receptor antagonist, as electroconvulsive therapy (ECT) anaesthetic in patients suffering from therapy-resistant depression. We included 42 patients who received ECT treatment with either ketamine (n = 16) or the barbiturate thiopental (n = 26). We analysed the number of sessions until completion of ECT treatment (used as a surrogate parameter for outcome), psychopathology as assessed by pre- and post-ECT Mini-Mental State Examination (MMSE) and Hamilton Rating Scale for Depression (HAM-D) scores as well as ECT and seizure parameters (stimulation dose, seizure duration and concordance, urapidil dosage for post-seizure blood pressure management). The ketamine group needed significantly fewer ECT sessions and had significantly lower HAM-D and higher MMSE scores afterwards. As expected, the ketamine group needed more urapidil for blood pressure control. Taking into account the limits inherent in a retrospective study design and the rather small sample size, our results nonetheless point towards synergistic effects of ECT and ketamine anaesthesia, less cognitive side effects and good tolerability of ketamine.

Ketamine Patient Controlled Analgesia for Acute Pain in Trauma Patients: A Randomized, Active Comparator Controlled, Blinded, Pilot Trial

DTIC Science & Technology

2017-01-11

patient- controlled analgesia per the primary treating team. Four subjects in the ketamine group and one subject in the hydromorphone group withdrew...occurred more frequently in the ketamine group , although this was not statistically significant (40% vs. 0%, P=0.090). Ketamine patient- controlled ...breakthrough IV morphine equivalents between groups . 4.0 RESULTS 4.1 Participants Due to unanticipated barriers to enrollment, including a

Studies of the biotransformation and pharmacology of ketamine and its metabolites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leung, Y.

1986-01-01

The first part of the research is concerned with the synthesis, resolution and metabolism of norketamine, the primary metabolite of ketamine. Incubations of racemic norketamine, individual enantiomers of norketamine and the pseudoracemates in rat liver microsomes revealed stereoselectivity and enantiomeric interactions during the metabolism of norketamine. The second part of the research describes the synthesis of 6-OH-norketamine, the major secondary metabolite of ketamine, and reports on its pharmacological activity and cerebral distribution in the rat. Primary deuterium isotope effects associated with the metabolism and pharmacological activity of ketamine-N-CD/sub 3/ were examined in the third part of this research. The lastmore » part of the research deals with the effect of diazepam on the metabolic transformation of ketamine to norketamine in the rat. The fractions of ketamine metabolized to norketamine were found not to be different in the presence or the absence of diazepam.« less

The promise of ketamine for treatment-resistant depression: current evidence and future directions

PubMed Central

DeWilde, Kaitlin E.; Levitch, Cara F.; Murrough, James W.; Mathew, Sanjay J.; Iosifescu, Dan V.

2014-01-01

Major depressive disorder (MDD) is one of the most disabling diseases worldwide and is a significant public health threat. Current treatments for MDD primarily consist of monoamine-targeting agents and have limited efficacy. However, the glutamate neurotransmitter system has recently come into focus as a promising alternative for novel antidepressant treatments. We review the current data on the glutamate NMDA receptor antagonist ketamine, which has been shown in clinical trials to act as a rapid antidepressant in MDD. We also examine ketamine efficacy on dimensions of psychopathology, including anhedonia, cognition, and suicidality, consistent with the NIMH Research Domain Criteria (RDoC) initiative. Other aspects of ketamine reviewed in this paper include safety and efficacy, different administration methods, and the risks of misuse of ketamine outside of medical settings. Finally, we conclude with a discussion of other glutamatergic agents other than ketamine currently being tested as novel antidepressants. PMID:25649308

Rapid Resolution of Grief with IV Infusion of Ketamine: A Unique Phenomenological Experience

PubMed Central

Gowda, Mahesh Ramanna; Srinivasa, Preethi; Kumbar, Prabha S.; Ramalingaiah, Vinay Hosagavi; Muthyalappa, Chandrashekar; Durgoji, Sumit

2016-01-01

Ketamine, a primarily FDA-approved anaesthetic agent is also used as recreational drug. Based on preclinical findings and later the clinical observations it is noted to have rapid antidepressant effect due to its mechanisms related to NMDA antagonism. In spite of established evidence of ketamine being effective in depression with significant role in treatment resistant cases as well, there was absolute dearth of literature regarding its utility in grief-related disorders. In this context we present a case of 28-year-old graduate male who presented to us in complicated grief following death of his wife due to obstetric complications. With the patient and immediate family members consenting for use of ketamine as off-label use, patient had single IV infusion of ketamine following which he had unique phenomenological experience ultimately resolving his grief in few minutes. Through this case we highlight the enormous therapeutic promise of ketamine in complicated grief. PMID:27011405

[Preparing oral dosage form of ketamine in the hospital for simplicity and patient compliance--preparations using agar].

PubMed

Kaneuchi, Miki; Kohri, Naonori; Senbongi, Kaname; Sakai, Hideo; Iseki, Ken

2005-02-01

Ketamine has been widely used in the operation as intravenous and intramuscular injections, since ketamine has dissociative anesthetic properties. When it is given in sub-anesthetic dose, ketamine is known to have an analgesic effect. The analgesic effect is observed for patients with neuropathic pain when administrated not only by injection but also orally. In Japan, since ketamine is not commercially available except injection forms, patients have to take it as solution of injections for the oral medication. Since the solution of injections has extremely bitter taste, patients intensely desire the development of preparations without the bitterness. In the present study, we prepared oral gel dosage forms of ketamine using agar. It is simple to prepare this dosage form, and most pharmacists can prepare it easily in many hospitals. This gel dosage form met content uniformity requirements and the shape of that was maintained intact during the dissolution test (for 10 hours). The release rate was reduced by additions of additives such as sugar and a flavor in the gel. The reason for the reduction in release could be the suppression of ketamine diffusion depended on the micro-viscosity of solution in the gel. The ketamine contents and the release profile of the gel preparations were unchanged at the room temperature for 12-week storage. The gel preparations in this study would be useful for the oral medication of ketamine, since it is easy for patients to carry them when they go out and the intensely bitter taste could be improved by the addition of a flavor.

Preliminary analysis of positive and negative syndrome scale in ketamine-associated psychosis in comparison with schizophrenia.

PubMed

Xu, Ke; Krystal, John H; Ning, Yuping; Chen, Da Chun; He, Hongbo; Wang, Daping; Ke, Xiaoyin; Zhang, Xifan; Ding, Yi; Liu, Yuping; Gueorguieva, Ralitza; Wang, Zuoheng; Limoncelli, Diana; Pietrzak, Robert H; Petrakis, Ismene L; Zhang, Xiangyang; Fan, Ni

2015-02-01

Studies of the effects of the N-methyl-d-aspartate (NMDA) glutamate receptor antagonist, ketamine, have suggested similarities to the symptoms of schizophrenia. Our primary goal was to evaluate the dimensions of the Positive and Negative Syndrome Scale (PANSS) in ketamine users (acute and chronic) compared to schizophrenia patients (early and chronic stages). We conducted exploratory factor analysis for the PANSS from four groups: 135 healthy subject administrated ketamine or saline, 187 inpatients of ketamine abuse; 154 inpatients of early course schizophrenia and 522 inpatients of chronic schizophrenia. Principal component factor analyses were conducted to identify the factor structure of the PANSS. Factor analysis yielded five factors for each group: positive, negative, cognitive, depressed, excitement or dissociation symptoms. The symptom dimensions in two schizophrenia groups were consistent with the established five-factor model (Wallwork et al., 2012). The factor structures across four groups were similar, with 19 of 30 symptoms loading on the same factor in at least 3 of 4 groups. The factors in the chronic ketamine group were more similar to the factors in the two schizophrenia groups rather than to the factors in the acute ketamine group. Symptom severities were significantly different across the groups (Kruskal-Wallis χ(2)(4) = 540.6, p < 0.0001). Symptoms in the two ketamine groups were milder than in the two schizophrenia groups (Cohen's d = 0.7). Our results provide the evidence of similarity in symptom dimensions between ketamine psychosis and schizophrenia psychosis. The interpretations should be cautious because of potential confounding factors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ketamine-induced behavioural and brain oxidative changes in mice: an assessment of possible beneficial effects of zinc as mono- or adjunct therapy.

PubMed

Onaolapo, Olakunle James; Ademakinwa, Olayemi Quyyom; Olalekan, Temitayo Opeyemi; Onaolapo, Adejoke Yetunde

2017-09-01

We studied the influence of zinc, haloperidol or olanzapine on neurobehaviour (open-field, radial arm maze and elevated plus maze) and brain antioxidant status in vehicle- or ketamine-treated mice, with the aim of ascertaining the potentials of zinc in counteracting ketamine's effects. Experiment 1 assessed the effects of zinc in healthy animals and the relative degrees of modulation of ketamine's effects by zinc, haloperidol or olanzapine, respectively. Experiment 2 assessed the modulation of ketamine's effects following co-administration of zinc with haloperidol or olanzapine. Male mice weighing 18-20 g each were used. Animals were pretreated with ketamine (except vehicle, zinc, haloperidol and olanzapine controls) for 10 days before commencement of 14-day treatment (day 11-24) with vehicle, zinc, haloperidol or olanzapine (alone or in combination). Ketamine injection also continued alongside zinc and/or standard drugs in the ketamine-treated groups. Zinc, haloperidol and olanzapine were administered by gavage. Treatments were given daily and behaviours assessed on days 11 and 24. On day 24, animals were sacrificed and whole brain homogenates used for estimation of glutathione, nitric oxide and malondialdehyde (MDA) levels. Ketamine increased open-field behaviours, nitric oxide and MDA levels, while it decreased working memory, social interaction and glutathione. Administration of zinc alone or in combination with haloperidol or olanzapine was associated with variable degrees of reversal of these effects. Zinc may have the potential of a possible therapeutic agent and/or adjunct in the reversal of schizophrenia-like changes in behaviour and brain oxidative status.

Efficacy of Ketamine in Improving Pain after Tonsillectomy in Children: Meta-Analysis

PubMed Central

Cho, Hye Kyung; Kim, Kyu Won; Jeong, Yeon Min; Lee, Ho Seok; Lee, Yeon Ji; Hwang, Se Hwan

2014-01-01

Background and objectives The goal of this meta-analysis study was to perform a systematic review of the literature on the effects of ketamine on postoperative pain following tonsillectomy and adverse effects in children. Subjects and Methods Two authors independently searched three databases (MEDLINE, SCOPUS, Cochrane) from their inception of article collection to February 2014. Studies that compared preoperative ketamine administration (ketamine groups) with no treatment (control group) or opioid administration (opioid group) where the outcomes of interest were postoperative pain intensity, rescue analgesic consumption, or adverse effects (sedation, nausea and vomiting, bad dream, worsening sleep pattern, and hallucination) 0–24 hours after leaving the operation room were included in the analysis. Results The pain score reported by the physician during first 4 hours and need for analgesics during 24 hours postoperatively was significantly decreased in the ketamine group versus control group and was similar with the opioid group. In addition, there was no significant difference between ketamine and control groups for adverse effects during 24 hours postoperatively. In the subgroup analyses (systemic and local administration) regarding pain related measurements, peritonsillar infiltration of ketamine was more effective in reducing the postoperative pain severity and need for analgesics. Conclusion Preoperative administration of ketamine systemically or locally could provide pain relief without side-effects in children undergoing tonsillectomy. However, considering the insufficient evaluation of efficacy of ketamine according to the administration methods and high heterogeneity in some parameters, further clinical trials with robust research methodology should be conducted to confirm the results of this study. PMID:24979227

Oral Ketamine in the Palliative Care Setting: A Review of the Literature and Case Report of a Patient With Neurofibromatosis Type 1 and Glomus Tumor-Associated Complex Regional Pain Syndrome

PubMed Central

Soto, Eliezer; Stewart, Douglas R.; Mannes, Andrew J.; Ruppert, Sarah L.; Baker, Karen; Zlott, Daniel; Handel, Daniel; Berger, Ann M.

2014-01-01

Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has been shown to be effective not only for its anesthetic properties but also for the analgesic and opiate-sparing effects. However, data on efficacy and safety of oral ketamine for the treatment of neuropathic or cancer pain syndromes is limited with most of the evidence based on small clinical trials and anecdotal experiences. In this review, we will analyze the clinical data on oral ketamine in the palliative care setting. After an extensive search using five major databases, a total of 19 relevant articles were included. No official clinical guidelines for the use of oral ketamine in this patient population were found. Studies on oral ketamine for cancer and neuropathic pain have shown mixed results which could be partially due to significant differences in hepatic metabolism. In addition, we will include a case report of a 38-year-old female with neurofibromatosis type 1 (NF1) with history of chronic, severe pain in her fingertips secondary to multiple glomus tumors which evolved into CRPS resistant to multiple therapies but responsive to oral ketamine. Based on our experience with oral ketamine, this drug should be administered after an intravenous trial to monitor response and side effects in patients with an adequate functional status. However, patients in the palliative care and hospice setting, especially the one at the end of their lives, may also benefit from oral ketamine even if an intravenous trial is not feasible. PMID:21803784

Ketamine treatment involves medial prefrontal cortex serotonin to induce a rapid antidepressant-like activity in BALB/cJ mice.

PubMed

Pham, T H; Mendez-David, I; Defaix, C; Guiard, B P; Tritschler, L; David, D J; Gardier, A M

2017-01-01

Unlike classic serotonergic antidepressant drugs, ketamine, an NMDA receptor antagonist, exhibits a rapid and persistent antidepressant (AD) activity, at sub-anaesthetic doses in treatment-resistant depressed patients and in preclinical studies in rodents. The mechanisms mediating this activity are unclear. Here, we assessed the role of the brain serotonergic system in the AD-like activity of an acute sub-anaesthetic ketamine dose. We compared ketamine and fluoxetine responses in several behavioral tests currently used to predict anxiolytic/antidepressant-like potential in rodents. We also measured their effects on extracellular serotonin levels [5-HT] ext in the medial prefrontal cortex (mPFCx) and brainstem dorsal raphe nucleus (DRN), a serotonergic nucleus involved in emotional behavior, and on 5-HT cell firing in the DRN in highly anxious BALB/cJ mice. Ketamine (10 mg/kg i.p.) had no anxiolytic-like effect, but displayed a long lasting AD-like activity, i.e., 24 h post-administration, compared to fluoxetine (18 mg/kg i.p.). Ketamine (144%) and fluoxetine (171%) increased mPFCx [5-HT] ext compared to vehicle. Ketamine-induced AD-like effect was abolished by a tryptophan hydroxylase inhibitor, para-chlorophenylalanine (PCPA) pointing out the role of the 5-HT system in its behavioral activity. Interestingly, increase in cortical [5-HT] ext following intra-mPFCx ketamine bilateral injection (0.25 μg/side) was correlated with its AD-like activity as measured on swimming duration in the FST in the same mice. Furthermore, pre-treatment with a selective AMPA receptor antagonist (intra-DRN NBQX) blunted the effects of intra-mPFCx ketamine on both the swimming duration in the FST and mPFCx [5-HT] ext suggesting that the AD-like activity of ketamine required activation of DRN AMPA receptors and recruited the prefrontal cortex/brainstem DRN neural circuit in BALB/c mice. These results confirm a key role of cortical 5-HT release in ketamine's AD-like activity following the blockade of glutamatergic NMDA receptors. Tight interactions between mPFCx glutamatergic and serotonergic systems may explain the differences in this activity between ketamine and fluoxetine in vivo. This article is part of the Special Issue entitled 'Ionotropic glutamate receptors'. Copyright © 2016. Published by Elsevier Ltd.

Ketamine use in current clinical practice

PubMed Central

Gao, Mei; Rejaei, Damoon; Liu, Hong

2016-01-01

After nearly half a century on the market, ketamine still occupies a unique corner in the medical armamentarium of anesthesiologists or clinicians treating pain. Over the last two decades, much research has been conducted highlighting the drug's mechanisms of action, specifically those of its enantiomers. Nowadays, ketamine is also being utilized for pediatric pain control in emergency department, with its anti-hyperalgesic and anti-inflammatory effects being revealed in acute and chronic pain management. Recently, new insights have been gained on ketamine's potential anti-depressive and antisuicidal effects. This article provides an overview of the drug's pharmacokinetics and pharmacodynamics while also discussing the potential benefits and risks of ketamine administration in various clinical settings. PMID:27018176

Behavioral and biochemical effects of ketamine and dextromethorphan relative to its antidepressant-like effects in Swiss Webster mice

PubMed Central

Nguyen, Linda; Lucke-Wold, Brandon P.; Logsdon, Aric F.; Scandinaro, Anna L.; Huber, Jason D.; Matsumoto, Rae R.

2016-01-01

Ketamine has been shown to produce rapid and robust antidepressant effects in depressed individuals, however its abuse potential and adverse psychotomimetic effects limit its widespread use. Dextromethorphan may serve as a safer alternative based on pharmacodynamic similarities to ketamine. In this proof of concept study, behavioral and biochemical analyses were undertaken to evaluate the potential involvement of brain derived neurotrophic factor (BDNF) in the antidepressant-like effects of dextromethorphan in mice, with comparisons to ketamine and imipramine. Male Swiss, Webster mice were injected with dextromethorphan, ketamine or imipramine and their behaviors evaluated in the forced swim test (FST) and open field test. Western blots were used to measure brain derived neurotrophic factor (BDNF) and its precursor, pro-BDNF, protein expression in the hippocampus and frontal cortex of these mice. Our results show dextromethorphan and imipramine each reduced immobility time in the FST without affecting locomotor activity, whereas ketamine reduced immobility time and increased locomotor activity. Ketamine also rapidly (within 40 min) increased pro-BDNF expression in an AMPA receptor-dependent manner in the hippocampus, while DM and imipramine did not alter pro-BDNF or BDNF levels in either the hippocampus or frontal cortex within this timeframe. These data demonstrate that dextromethorphan shares some features with both ketamine and imipramine. Additional studies looking at dextromethorphan may aid in the development of more rapid, safe, and efficacious antidepressant treatment. PMID:27580401

Posttraumatic administration of a sub-anesthetic dose of ketamine exerts neuroprotection via attenuating inflammation and autophagy.

PubMed

Wang, C-Q; Ye, Y; Chen, F; Han, W-C; Sun, J-M; Lu, X; Guo, R; Cao, K; Zheng, M-J; Liao, L-C

2017-02-20

As a complex disease, traumatic brain injury (TBI) can result in long-term psychiatric changes and sensorimotor and cognitive impairments. The TBI-induced loss of memory and long-term cognitive dysfunction are related to mechanistic factors including an increased inflammatory response, autophagy, edema, and ischemia. Many published studies have offered evidence for the neuroprotective effects and anti-inflammatory properties of ketamine for TBI patients. Nonetheless, there is a limited understanding of the accurate mechanism that underlies the potential neuroprotective effects of ketamine. Herein, it can be shown that posttraumatic administration of ketamine at a sub-anesthetic dose (10mg/kg ketamine, every 24h up to 7days) can prevent the TBI-induced production of IL-6 and TNF-α, attenuate deficits of dendrites and spines and exert beneficial effects on memory and behavior. Moreover, studies show that ketamine may activate the mTOR signaling pathway by p-mTOR induction to down-regulate the expression of crucial autophagic proteins such as LC3 and Beclin-1. According to these findings, ameliorating secondary brain injury and anti-inflammatory properties is closely related to the neuroprotection of ketamine, which supports the use of ketamine as a potential therapy for patients with TBI to alleviate functional deficits. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Suppression of RAGE and TLR9 by Ketamine Contributes to Attenuation of Lipopolysaccharide-Induced Acute Lung Injury.

PubMed

Yang, Chunyan; Song, Yulong; Wang, Hui

2017-06-01

The present study aimed to investigate the protective role of ketamine in lipopolysaccharide (LPS)-induced acute lung injury (ALI) by the inhibition of the receptor for advanced glycation end products (RAGE) and toll-like receptor 9 (TLR9). ALI was induced in rats by intratracheal instillation of LPS (5 mg/kg), and ketamine (5, 7.5, and 10 mg/kg) was injected intraperitoneally 1 h after LPS administration. Meanwhile, A549 alveolar epithelial cells were incubated with LPS in the presence or absence of ketamine. After 24 h, bronchoalveolar lavage fluid (BALF) and lung tissue were collected. Ketamine posttreatment at doses of 5, 7.5, and 10 mg/kg decreased LPS-induced evident lung histopathological changes, lung wet-to-dry weight ratio, and lung myeloperoxidase activity. In addition, posttreatment with ketamine-inhibited inflammatory cells and inflammatory mediators including tumor necrosis factor-α, interleukin-6, and high-mobility group box 1 in BALF. Furthermore, we demonstrated that ketamine-inhibited LPS-induced RAGE and TLR9 protein up-expressions and the phosphorylation of I-κB-α and nuclear factor-κB (NF-κB) p65 in vivo and in vitro. The results presented here suggest that the protective mechanism of ketamine may be attributed partly to decreased production of inflammatory mediators through the inhibition of RAGE/TLR9-NF-κB pathway.

Signal-transducing mechanisms of ketamine-caused inhibition of interleukin-1{beta} gene expression in lipopolysaccharide-stimulated murine macrophage-like Raw 264.7 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, T.-L.; Chang, C.-C.; Lin, Y.-L.

2009-10-01

Ketamine may affect the host immunity. Interleukin-1{beta} (IL-1{beta}), IL-6, and tumor necrosis factor-{alpha} (TNF-{alpha}) are pivotal cytokines produced by macrophages. This study aimed to evaluate the effects of ketamine on the regulation of inflammatory cytokine gene expression, especially IL-1{beta}, in lipopolysaccharide (LPS)-activated murine macrophage-like Raw 264.7 cells and its possible signal-transducing mechanisms. Administration of Raw 264.7 cells with a therapeutic concentration of ketamine (100 {mu}M), LPS, or a combination of ketamine and LPS for 1, 6, and 24 h was not cytotoxic to macrophages. Exposure to 100 {mu}M ketamine decreased the binding affinity of LPS and LPS-binding protein but didmore » not affect LPS-induced RNA and protein synthesis of TLR4. Treatment with LPS significantly increased IL-1{beta}, IL-6, and TNF-{alpha} gene expressions in Raw 264.7 cells. Ketamine at a clinically relevant concentration did not affect the synthesis of these inflammatory cytokines, but significantly decreased LPS-caused increases in these cytokines. Immunoblot analyses, an electrophoretic mobility shift assay, and a reporter luciferase activity assay revealed that ketamine significantly decreased LPS-induced translocation and DNA binding activity of nuclear factor-kappa B (NF{kappa}B). Administration of LPS sequentially increased the phosphorylations of Ras, Raf, MEK1/2, ERK1/2, and IKK. However, a therapeutic concentration of ketamine alleviated such augmentations. Application of toll-like receptor 4 (TLR4) small interfering (si)RNA reduced cellular TLR4 amounts and ameliorated LPS-induced RAS activation and IL-1{beta} synthesis. Co-treatment with ketamine and TLR4 siRNA synergistically ameliorated LPS-caused enhancement of IL-1{beta} production. Results of this study show that a therapeutic concentration of ketamine can inhibit gene expression of IL-1{beta} possibly through suppressing TLR4-mediated signal-transducing phosphorylations of Ras, Raf, MEK1/2, ERK1/2, and IKK and subsequent translocation and transactivation of NF{kappa}B.« less

Neuronal correlates of ketamine and walking induced gamma oscillations in the medial prefrontal cortex and mediodorsal thalamus

PubMed Central

McCoy, Alex J.; Dodge, Caroline; Walters, Judith R.; Buonanno, Andres; Delaville, Claire

2017-01-01

Alterations in the function of the medial prefrontal cortex (mPFC) and its major thalamic source of innervation, the mediodorsal (MD) thalamus, have been hypothesized to contribute to the symptoms of schizophrenia. The NMDAR antagonist ketamine, used to model schizophrenia, elicits a brain state resembling early stage schizophrenia characterized by cognitive deficits and increases in cortical low gamma (40–70 Hz) power. Here we sought to determine how ketamine differentially affects spiking and gamma local field potential (LFP) activity in the rat mPFC and MD thalamus. Additionally, we investigated the ability of drugs targeting the dopamine D4 receptor (D4R) to modify the effects of ketamine on gamma activity as a measure of potential cognitive therapeutic efficacy. Rats were trained to walk on a treadmill to reduce confounds related to hyperactivity after ketamine administration (10 mg/kg s.c.) while recordings were obtained from electrodes chronically implanted in the mPFC and MD thalamus. Ketamine increased gamma LFP power in mPFC and MD thalamus in a similar frequency range, yet did not increase thalamocortical synchronization. Ketamine also increased firing rates and spike synchronization to gamma oscillations in the mPFC but decreased both measures in MD thalamus. Conversely, walking alone increased both firing rates and spike-gamma LFP correlations in both mPFC and MD thalamus. The D4R antagonist alone (L-745,870) had no effect on gamma LFP power during treadmill walking, although it reversed increases induced by the D4R agonist (A-412997) in both mPFC and MD thalamus. Neither drug altered ketamine-induced changes in gamma power or firing rates in the mPFC. However, in MD thalamus, the D4R agonist increased ketamine-induced gamma power and prevented ketamine’s inhibitory effect on firing rates. Results provide new evidence that ketamine differentially modulates spiking and gamma power in MD thalamus and mPFC, supporting a potential role for both areas in contributing to ketamine-induced schizophrenia-like symptoms. PMID:29095852

Clozapine counteracts a ketamine-induced depression of hippocampal-prefrontal neuroplasticity and alters signaling pathway phosphorylation

PubMed Central

Rame, Marion; Caudal, Dorian; Schenker, Esther; Svenningsson, Per; Spedding, Michael; Jay, Thérèse M.

2017-01-01

Single sub-anesthetic doses of ketamine can exacerbate the symptoms of patients diagnosed with schizophrenia, yet similar ketamine treatments rapidly reduce depressive symptoms in major depression. Acute doses of the atypical antipsychotic drug clozapine have also been shown to counteract ketamine-induced psychotic effects. In the interest of understanding whether these drug effects could be modeled with alterations in neuroplasticity, we examined the impact of acutely-administered ketamine and clozapine on in vivo long-term potentiation (LTP) in the rat’s hippocampus-to-prefrontal cortex (H-PFC) pathway. We found that a low dose of ketamine depressed H-PFC LTP, whereas animals that were co-administrated the two drugs displayed LTP that was similar to a saline-treated control. To address which signaling molecules might mediate such effects, we also examined phosphorylation and total protein levels of GSK3β, GluA1, TrkB, ERK, and mTOR in prefrontal and hippocampal sub-regions. Among the statistically significant effects that were detected (a) both ketamine and clozapine increased the phosphorylation of Ser9-GSK3β throughout the prefrontal cortex and of Ser2481-mTOR in the dorsal hippocampus (DH), (b) clozapine increased the phosphorylation of Ser831-GluA1 throughout the prefrontal cortex and of Ser845-GluA1 in the ventral hippocampus, (c) ketamine treatment increased the phosphorylation of Thr202/Tyr204-ERK in the medial PFC (mPFC), and (d) clozapine treatment was associated with decreases in the phosphorylation of Tyr705-TrkB in the DH and of Try816-TrkB in the mPFC. Further analyses involving phosphorylation effect sizes also suggested Ser831-GluA1 in the PFC displayed the highest degree of clozapine-responsivity relative to ketamine. These results provide evidence for how ketamine and clozapine treatments affect neuroplasticity and signaling pathways in the stress-sensitive H-PFC network. They also demonstrate the potential relevance of H-PFC pathway neuroplasticity for modeling ketamine-clozapine interactions in regards to psychosis. PMID:28472198

Subanesthetic ketamine for pain management in hospitalized children, adolescents, and young adults: a single-center cohort study

PubMed Central

Sheehy, Kathy A; Lippold, Caroline; Rice, Amy L; Nobrega, Raissa; Finkel, Julia C; Quezado, Zenaide MN

2017-01-01

Background Subanesthetic doses of ketamine, an N-methyl-d-aspartate receptor antagonist used as an adjuvant to opioid for the treatment of pain in adults with acute and chronic pain, have been shown, in some instances, to improve pain intensity and to decrease opioid intake. However, less is known about the role of ketamine in pain management in children, adolescents, and young adults. Purpose We examined the effects of subanesthetic ketamine on pain intensity and opioid intake in children, adolescents, and young adults with acute and chronic pain syndromes treated in an inpatient setting. Methods This is a longitudinal cohort study of patients treated with subanesthetic ketamine infusions in regular patient care units in a tertiary pediatric hospital. Primary outcomes included changes in pain scores and morphine-equivalent intake. Results The study cohort included 230 different patients who during 360 separate hospital admissions received subanesthetic ketamine infusions for pain management. Overall, ketamine infusions were associated with significant reductions in mean pain scores from baseline (mean pain scores 6.64 [95% CI: 6.38–6.90]) to those recorded on the day after discontinuation of ketamine (mean pain scores 4.38 [95% CI: 4.06–4.69]), p<0.001. Importantly, the effect of ketamine on pain scores varied according to clinical diagnosis (p=0.011), infusion duration (p=0.004), and pain location (p=0.004). Interestingly, greater reductions in pain scores were observed in patients with cancer pain and patients with pain associated with pancreatitis and Crohn’s disease. There were no records of psychotomimetic side effects requiring therapy. Conclusion These data suggest that administration of subanesthetic ketamine for pain management is feasible and safe in regular inpatient care units and may benefit children, adolescents, and young adults with acute and chronic pain. This study is informative and can be helpful in determining sample and effect sizes when planning clinical trials to determine the role of subanesthetic ketamine infusions for pain management in pediatric patients. PMID:28435316

Effect of ketamine on exploratory behaviour in BALB/C and C57BL/6 mice.

PubMed

Akillioglu, Kubra; Melik, Emine Babar; Melik, Enver; Boga, Ayper

2012-01-01

In this study, we evaluated the effect of ketamine on exploratory locomotion behaviours in the Balb/c and C57BL/6 strains of mice, which differ in their locomotion behaviours. Intraperitoneal administration of ketamine at three different doses (1, 5 or 10 mg/kg, 0.1 ml/10 gr body weight) was performed on adult male Balb/c and C57BL/6 mice. The same volume of saline was applied to the control group. The open-field and elevated plus maze apparatus were used to evaluate exploratory locomotion. In the open-field test, Balb/c mice less spend time in the centre of the field and was decreased locomotor activity compared to C57BL/6 mice (p<0.01). Ketamine treatment of Balb/c mice at 10 mg/kg dose caused an increase in locomotor activity and an increase in the amount of time spent in the centre in the open-field test, compared to the control group (p<0.05). In C57BL/6 mice, ketamine treatment (1 and 10 mg/kg) decreased locomotor activity (p<0.05). In C57BL/6 mice, the three different doses of ketamine application each caused a decrease in the frequency of centre crossing (p<0.001) and the spent time in the centre (p<0.05). In the elevated plus maze, the number of open-arm entries, the percentage of open-arm time and total arm entries were decreased in Balb/c mice compared to C57BL/6 mice (p<0.001). Ketamine treatment of Balb/c mice at 10 mg/kg dose caused an increase in the open-arm activity (p<0.001). Ketamine application (10 mg/kg) decreased the open-arm activity in C57BL/6 mice (p<0.05). A subanaesthetic dose of ketamine increased exploratory locomotion in Balb/c mice. In contrast, a subanaesthetic dose of ketamine decreased exploratory locomotion in C57BL/6 mice. In conclusion, hereditary factors may play an important role in ketamine-induced responses. Copyright © 2011 Elsevier Inc. All rights reserved.

Morphological and behavioral responses of zebrafish after 24 h of ketamine embryonic exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Félix, Luís M., E-mail: lfelix@utad.pt

Ketamine, one anesthetic used as an illicit drug, has been detected both in freshwater and marine ecosystems. However, knowledge of its impact on aquatic life is still limited. This study aimed to test its effects in zebrafish embryos by analyzing its time- and dose-dependent developmental toxicity and long-term behavioral changes. The 24 h-LC{sub 50} was calculated from percent survival using probit analysis. Based on the 24 h-LC{sub 50} (94.4 mg L{sup −1}), embryos (2 hour post-fertilization - hpf) were divided into four groups, including control, and exposed for 24 h to ketamine concentrations of 50, 70 or 90 mg L{supmore » −1}. Developmental parameters were evaluated on the course of the experimental period, and anatomical abnormalities and locomotor deficits were analyzed at 144 hpf. Although the portion of ketamine transferred into the embryo was higher in the lowest exposed group (about 0.056 ± 0.020 pmol per embryo), the results showed that endpoints such as increased mortality, edema, heart rate alterations, malformation and abnormal growth rates were significantly affected. At 144 hpf, the developmental abnormalities included thoracic and trunk abnormalities in the groups exposed to 70 and 90 mg L{sup −1}. Defects in cartilage (alcian blue) and bone (calcein) elements also corroborated the craniofacial anomalies observed. A significant up-regulation of the development-related gene nog3 was detected by qRT-PCR at 8 hpf. Early exposure to ketamine also resulted in long-term behavioral changes, such as an increase in thigmotaxis and disruption of avoidance behavior at 144 hpf. Altogether, this study provides new evidence on the ketamine teratogenic potential, indicating a possible pharmacological impact of ketamine in aquatic environments. - Highlights: • 24 h exposure to ketamine increases mortality. • Morphological changes were observed after exposure. • Exposure to ketamine leads to severe craniofacial anomalies. • Developmental gene expression changes in response to ketamine. • Developmental ketamine exposure produces lasting behavioral changes.« less

Population pharmacokinetic-pharmacodynamic modeling of ketamine-induced pain relief of chronic pain.

PubMed

Dahan, Albert; Olofsen, Erik; Sigtermans, Marnix; Noppers, Ingeborg; Niesters, Marieke; Aarts, Leon; Bauer, Martin; Sarton, Elise

2011-03-01

Pharmacological treatment of chronic (neuropathic) pain is often disappointing. In order to enhance our insight in the complex interaction between analgesic drug and chronic pain relief, we performed a pharmacokinetic-pharmacodynamic (PK-PD) modeling study on the effect of S(+)-ketamine on pain scores in Complex Regional Pain Syndrome type 1 (CRPS-1) patients. Sixty CRPS-1 patients were randomly allocated to received a 100-h infusion of S(+)-ketamine or placebo. The drug infusion rate was slowly increased from 5 mg/h (per 70 kg) to 20 mg/h based upon the effect/side effect profile. Pain scores and drug blood samples were obtained during the treatment phase and pain scores were further obtained weekly for another 11 weeks. A population PK-PD model was developed to analyze the S(+)-ketamine-pain data. Plasma concentrations of S(+)-ketamine and its metabolite decreased rapidly upon the termination of S(+)-ketamine infusion. The chance for an analgesic effect from ketamine and placebo treatment was 67±10% and 23±9% (population value±SE), respectively. The pain data were well described by the PK-PD model with parameters C(50)=10.5±4.8 ng/ml (95% ci 4.37-21.2 ng/ml) and t½ for onset/offset=10.9±4.0 days (5.3-20.5 days). Long-term S(+)-ketamine treatment is effective in causing pain relief in CRPS-1 patients with analgesia outlasting the treatment period by 50 days. These data suggest that ketamine initiated a cascade of events, including desensitization of excitatory receptor systems in the central nervous system, which persisted but slowly abated when ketamine molecules were no longer present. Copyright © 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.

Intravenous ketamine for subacute treatment of refractory chronic migraine: a case series.

PubMed

Lauritsen, Clinton; Mazuera, Santiago; Lipton, Richard B; Ashina, Sait

2016-12-01

Refractory migraine is a challenging condition with great impact on health related quality of life. Intravenous (IV) ketamine has been previously used to treat various refractory pain conditions. We present a series of patients with refractory migraine treated with intravenous ketamine in the hospital setting. Based on retrospective chart review, we identified six patients with refractory migraine admitted from 2010 through 2014 for treatment with intravenous ketamine. Ketamine was administered using a standard protocol starting with a dose of 0.1 mg/kg/hr and increased by 0.1 mg/kg/hr every 3 to 4 h as tolerated until the target pain score of 3/10 was achieved and maintained for at least 8 h. Visual Analogue Scale (VAS) scores at time of hospital admission were obtained as well as average baseline VAS scores prior to ketamine infusion. A phone interview was conducted for follow-up of migraine response in the 3 to 6 months following ketamine infusion. The study sample had a median age of 36.5 years (range 29-54) and 83% were women. Pre-treatment pain scores ranged from 9 to 10. All patients achieved a target pain level of 3 or less for 8 h; the average ketamine infusion rate at target was 0.34 mg/kg/hour (range 0.12-0.42 mg/kg/hr). One patient reported a transient out-of-body hallucination following an increase in the infusion rate, which resolved after decreasing the rate. There were no other significant side effects. IV ketamine was safely administered in the hospital setting to patients with refractory chronic migraine. Treatment was associated with short term improvement in pain severity in 6 of 6 patients with refractory chronic migraine. Prospective placebo-controlled trials are needed to assess short term and long-term efficacy of IV ketamine in refractory chronic migraine.

Potentiation of low dose ketamine effects by naltrexone: potential implications for the pharmacotherapy of alcoholism.

PubMed

Krystal, John H; Madonick, Steven; Perry, Edward; Gueorguieva, Ralitza; Brush, Laura; Wray, Yola; Belger, Aysenil; D'Souza, Deepak Cyril

2006-08-01

The interplay of opiate and NMDA glutamate receptors may contribute to psychosis, cognitive function, alcoholism, and substance dependence. Ketamine and ethanol block the NMDA glutamate receptor. The purpose of this randomized double-blind, placebo-controlled human laboratory study was to evaluate whether the interactive effects of drugs acting at opiate and NMDA glutamate receptors might partially explain the efficacy of naltrexone for the treatment of alcoholism, that is, whether naltrexone 25 mg pretreatment would modulate ketamine effects in healthy human subjects. Two groups of healthy subjects were studied. An initial group (n=31) received a perception-altering subanesthetic dose of ketamine (bolus of 0.23 mg/kg over 1 min followed by a 60-min infusion of 0.58 mg/kg or saline bolus and infusion). A second group (n=24) completed the same testing procedures, but received a subperceptual ketamine dose (bolus 0.081 mg/kg over 10 min followed by an infusion of 0.4 mg/kg/h). Ketamine produced positive symptoms, negative symptoms, emotional discomfort, and cognitive effects as measured by the Positive and Negative Syndrome Scale (PANSS) in a dose-related fashion. The lower ketamine dose produced subjective effects similar to two standard ethanol drinks, whereas the higher ketamine dose produced effects similar to five standard drinks. Although naltrexone produced no significant behavioral effects, it significantly magnified the increase in the total PANSS score produced by the lower subperceptual dose of ketamine, but not the higher perception-altering dose of ketamine. These data suggest that the interplay of opiate receptor antagonism and NMDA receptor antagonism may be relevant to the protective effects of naltrexone on alcohol consumption via potentiation of dysphoric effects associated with the NMDA receptor antagonist effects of ethanol. However, these data suggest that at levels of NMDA receptor antagonism associated with heavy drinking, this protective effect of naltrexone on drinking is no longer present.

Demonstration of analgesic effect of intranasal ketamine and intranasal fentanyl for postoperative pain after pediatric tonsillectomy.

PubMed

Yenigun, Alper; Yilmaz, Sinan; Dogan, Remzi; Goktas, Seda Sezen; Calim, Muhittin; Ozturan, Orhan

2018-01-01

Tonsillectomy is one of the oldest and most commonly performed surgical procedure in otolaryngology. Postoperative pain management is still an unsolved problem. In this study, our aim is to demonstrate the efficacy of intranasal ketamine and intranasal fentanyl for postoperative pain relief after tonsillectomy in children. This randomized-controlled study was conducted to evaluate the effects of intranasal ketamine and intranasal fentanyl in children undergoing tonsillectomy. Tonsillectomy performed in 63 children were randomized into three groups. Group I received: Intravenous paracetamol (10 mg/kg), Group II received intranasal ketamine (1.5 mg/kg ketamine), Group III received intranasal fentanyl (1.5 mcg/kg). The Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) and Wilson sedation scale scores were recorded at 15, 30, 60 min, 2 h, 6hr, 12 h and 24 h postoperatively. Patients were interviewed on the day after surgery to assess the postoperative pain, nightmares, hallucinations, nausea, vomiting and bleeding. Intranasal ketamine and intranasal fentanyl provided significantly stronger analgesic affects compared to intravenous paracetamol administration at postoperative 15, 30, 60 min and at 2, 6, 12 and 24 h in CHEOPS (p < 0.05). Sedative effects were observed in three patients in the intranasal ketamine administration group. No such sedative effect was seen in the groups that received intranasal fentanyl and intravenous paracetamol in Wilson Sedation Scale (p < 0.05). Cognitive impairment, constipation, nausea, vomiting and bleeding were not observed in any of the groups. This study showed that either intranasal ketamine and intranasal fentanyl were more effective than paracetamol for postoperative analgesia after pediatric tonsillectomy. Sedative effects were observed in three patients with the group of intranasal ketamine. There was no significant difference in the efficacy of IN Ketamine and IN Fentanyl for post-tonsillectomy pain. Copyright © 2017 Elsevier B.V. All rights reserved.

Rapid and sensitive detection of ketamine in blood using novel fluorescence genosensor.

PubMed

Ding, Yanjun; Li, Xingmei; Guo, Yadong; Yan, Jie; Ling, Jiang; Li, Weichen; Lan, Lingmei; Chang, Yunfeng; Cai, Jifeng; Zha, Lagabaiyla

2017-12-01

In recent years, drug abuse has been considered as a most challenging social problem that aroused public attention. Ketamine has increased in unregulated use as a 'recreational drug' in teenagers. However, there is no suitable and maneuverable detection method for ketamine in situ at the moment. Fluorescence sensor technique, with predominant recognition and simple operation, is a good potential application in drug detection. Here, we first reported a highly sensitive and selective fluorescence genosensor for rapid detection of ketamine based on DNA-templated silver nanoclusters (DNA-AgNCs) probes, in which the DNA sequence could specially recognize ketamine with high affinity. Parameters affecting detection efficiency were investigated and optimized. Under optimum conditions, the as-prepared genosensor can allow for the determination of ketamine in the concentration range of 0.0001-20 μg/mL with two linear equations: one is y = 2.84x-7.139 (R 2 = 0.987) for 0.0001-0.1 μg/mL, and the other is y = 1.87x-0.091 (R 2 = 0.962) for 0.1-20 μg/mL, and the estimated detection limit of ketamine is 0.06 ng/mL. Moreover, the feasibility of this proposed method was also demonstrated by analyzing forensic blood samples. Compared with official gas chromatography/mass spectrometry (GC/MS), this fluorescence genosensor is simple, rapid, and accurate for quantitative determination of ketamine in blood for pharmaceutical and forensic analysis. Overall, it is the first report on a fluorescence genosensor for detecting ketamine directly in blood. This research may provide a new insight for the analyst to band fluorescence genosensor technology together with drug monitoring in the battle against drug abuse and forensic examination. Graphical abstract High selectively detection of ketamine using a novel fluorescence genosensor based on DNA-AgNCs probe.

Subanesthetic ketamine infusions for the treatment of children and adolescents with chronic pain: a longitudinal study.

PubMed

Sheehy, Kathy A; Muller, Elena A; Lippold, Caroline; Nouraie, Mehdi; Finkel, Julia C; Quezado, Zenaide M N

2015-12-01

Chronic pain is common in children and adolescents and is often associated with severe functional disability and mood disorders. The pharmacological treatment of chronic pain in children and adolescents can be challenging, ineffective, and is mostly based on expert opinions and consensus. Ketamine, an N-methyl-D-aspartate receptor antagonist, has been used as an adjuvant for treatment of adult chronic pain and has been shown, in some instances, to improve pain and decrease opioid-requirement. We examined the effects of subanesthetic ketamine infusions on pain intensity and opioid use in children and adolescents with chronic pain syndromes treated in an outpatient setting. Longitudinal cohort study of consecutive pediatric patients treated with subanesthetic ketamine infusions in a tertiary outpatient center. Outcome measurements included self-reported pain scores (numeric rating scale) and morphine-equivalent intake. Over a 15-month period, 63 children and adolescents (median age 15, interquartile range 12-17 years) with chronic pain received 277 ketamine infusions. Intravenous administration of subanesthetic doses of ketamine to children and adolescents on an outpatient basis was safe and not associated with psychotropic effects or hemodynamic perturbations. Overall, ketamine significantly reduced pain intensity (p < 0.001) and yielded greater pain reduction in patients with complex regional pain syndrome (CRPS) than in patients with other chronic pain syndromes (p = 0.029). Ketamine-associated reductions in pain scores were the largest in postural orthostatic tachycardia syndrome (POTS) and trauma patients and the smallest in patients with chronic headache (p = 0.007). In 37% of infusions, patients had a greater than 20 % reduction in pain score. Conversely, ketamine infusions did not change overall morphine-equivalent intake (p = 0.3). These data suggest that subanesthetic ketamine infusion is feasible in an outpatient setting and may benefit children and adolescents with chronic pain. Further, patients with CRPS, POTS, and a history of trauma-related chronic pain are more likely to benefit from this therapeutic modality.

The Effect of a Single Dose of Intravenous Ketamine on Suicidal Ideation: A Systematic Review and Individual Participant Data Meta-Analysis.

PubMed

Wilkinson, Samuel T; Ballard, Elizabeth D; Bloch, Michael H; Mathew, Sanjay J; Murrough, James W; Feder, Adriana; Sos, Peter; Wang, Gang; Zarate, Carlos A; Sanacora, Gerard

2018-02-01

Suicide is a public health crisis with limited treatment options. The authors conducted a systematic review and individual participant data meta-analysis examining the effects of a single dose of ketamine on suicidal ideation. Individual participant data were obtained from 10 of 11 identified comparison intervention studies that used either saline or midazolam as a control treatment. The analysis included only participants who had suicidal ideation at baseline (N=167). A one-stage, individual participant data, meta-analytic procedure was employed using a mixed-effects, multilevel, general linear model. The primary outcome measures were the suicide items from clinician-administered (the Montgomery-Åsberg Depression Rating Scale [MADRS] or the Hamilton Depression Rating Scale [HAM-D]) and self-report scales (the Quick Inventory of Depressive Symptomatology-Self Report [QIDS-SR] or the Beck Depression Inventory [BDI]), obtained for up to 1 week after ketamine administration. Ketamine rapidly (within 1 day) reduced suicidal ideation significantly on both the clinician-administered and self-report outcome measures. Effect sizes were moderate to large (Cohen's d=0.48-0.85) at all time points after dosing. A sensitivity analysis demonstrated that compared with control treatments, ketamine had significant benefits on the individual suicide items of the MADRS, the HAM-D, and the QIDS-SR but not the BDI. Ketamine's effect on suicidal ideation remained significant after adjusting for concurrent changes in severity of depressive symptoms. Ketamine rapidly reduced suicidal thoughts, within 1 day and for up to 1 week in depressed patients with suicidal ideation. Ketamine's effects on suicidal ideation were partially independent of its effects on mood, although subsequent trials in transdiagnostic samples are required to confirm that ketamine exerts a specific effect on suicidal ideation. Additional research on ketamine's long-term safety and its efficacy in reducing suicide risk is needed before clinical implementation.

Antidepressant, anxiolytic and procognitive effects of subacute and chronic ketamine in the chronic mild stress model of depression.

PubMed

Papp, Mariusz; Gruca, Piotr; Lason-Tyburkiewicz, Magdalena; Willner, Paul

2017-02-01

Ketamine is the prototype of a new generation of antidepressant drugs, which is reported in clinical studies to be effective in treatment-resistant patients, with an effect that appears within hours and lasts for a few days. Chronic mild stress (CMS) is a well-established and widely used animal model of depression, in which anhedonia, anxiogenesis and cognitive dysfunction can be observed reliably. Studies using acute or brief ketamine treatment following withdrawal from CMS have replicated the clinical finding of a rapid onset of antidepressant action. However, there have been no CMS studies of chronic daily ketamine treatment or continued stress following ketamine treatment, which would have greater translational potential in relation to the long-term maintenance of antidepressant effects. Wistar rats were drug treated following an initial 2 weeks of CMS exposure, which continued alongside daily drug treatment. A first experiment tested a range of chronic (5 weeks) ketamine doses (5-30 mg/kg); a second compared the effects of subacute (3-5 days) and chronic (5 weeks) treatment. CMS-induced anhedonic, anxiogenic and dyscognitive effects, as measured, respectively, by decreased sucrose intake, avoidance of open arms in the elevated plus maze and loss of discrimination in the novel object recognition test. A sustained antidepressant-like effect of ketamine in the sucrose intake test was observed in both experiments, with an onset at around 1 week, faster than imipramine, and an optimum dose of 10 mg/kg. Anxiogenic and dyscognitive effects of CMS, in the elevated plus maze and novel object recognition test, respectively, were fully reversed by both subacute and chronic ketamine treatment. Daily treatment with ketamine in the CMS model causes sustained long-term antidepressant, anxiolytic and procognitive effects. The demonstration of a procognitive effect of ketamine may have particular translational value.

Ketamine for Social Anxiety Disorder: A Randomized, Placebo-Controlled Crossover Trial.

PubMed

Taylor, Jerome H; Landeros-Weisenberger, Angeli; Coughlin, Catherine; Mulqueen, Jilian; Johnson, Jessica A; Gabriel, Daniel; Reed, Margot O; Jakubovski, Ewgeni; Bloch, Michael H

2018-01-01

Many patients with social anxiety disorder (SAD) experience inadequate symptom relief from available treatments. Ketamine is a potent N-methyl-D-aspartate receptor antagonist with a potentially novel mechanism of action for the treatment of anxiety disorders. Therefore, we conducted a double-blind, randomized, placebo-controlled crossover trial in 18 adults with DSM-5 SAD and compared the effects between intravenous ketamine (0.5 mg/kg over 40 min) and placebo (normal saline) on social phobia symptoms. Ketamine and placebo infusions were administered in a random order with a 28-day washout period between infusions. Ratings of anxiety were assessed 3-h post-infusion and followed for 14 days. We used linear mixed models to assess the impact of ketamine and placebo on anxiety symptoms. Outcomes were blinded ratings on the Liebowitz Social Anxiety Scale (LSAS) and self-reported anxiety on a visual analog scale (VAS-Anxiety). We also used the Wilcoxon signed-rank test to compare the proportion of treatment responders. Based on prior studies, we defined response as a greater than 35% LSAS reduction and 50% VAS-Anxiety reduction. We found ketamine resulted in a significantly greater reduction in anxiety relative to placebo on the LSAS (Time × Treatment: F 9,115 =2.6, p=0.01) but not the VAS-Anxiety (Time × Treatment: F 10,141 =0.4, p=0.95). Participants were significantly more likely to exhibit a treatment response after ketamine infusion relative to placebo in the first 2 weeks following infusion measured on the LSAS (33.33% response ketamine vs 0% response placebo, Wilcoxon signed-rank test z=2.24, p=0.025) and VAS (88.89% response ketamine vs 52.94% response placebo, Wilcoxon signed-rank test z=2.12, p=0.034). In conclusion, this proof-of-concept trial provides initial evidence that ketamine may be effective in reducing anxiety.

Inhibition by ketamine and amphetamine analogs of the neurogenic nitrergic vasodilations in porcine basilar arteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Mei-Fang

The abuse of ketamine and amphetamine analogs is associated with incidence of hypertension and strokes involving activation of sympathetic activities. Large cerebral arteries at the base of the brain from several species receive dense sympathetic innervation which upon activation causes parasympathetic-nitrergic vasodilation with increased regional blood flow via axo-axonal interaction mechanism, serving as a protective mechanism to meet O{sub 2} demand in an acutely stressful situation. The present study was designed to examine effects of ketamine and amphetamine analogs on axo-axonal interaction-mediated neurogenic nitrergic vasodilation in porcine basilar arteries using techniques of blood-vessel myography, patch clamp and two-electrode voltage clamp,more » and calcium imaging. In U46619-contracted basilar arterial rings, nicotine (100 μM) and electrical depolarization of nitrergic nerves by transmural nerve stimulation (TNS, 8 Hz) elicited neurogenic nitrergic vasodilations. Ketamine and amphetamine analogs concentration-dependently inhibited nicotine-induced parasympathetic-nitrergic vasodilation without affecting that induced by TNS, nitroprusside or isoproterenol. Ketamine and amphetamine analogs also concentration-dependently blocked nicotine-induced inward currents in Xenopus oocytes expressing α3β2-nicotinic acetylcholine receptors (nAChRs), and nicotine-induced inward currents as well as calcium influxes in rat superior cervical ganglion neurons. The potency in inhibiting both inward-currents and calcium influxes is ketamine > methamphetamine > hydroxyamphetamine. These results indicate that ketamine and amphetamine analogs, by blocking nAChRs located on cerebral perivascular sympathetic nerves, reduce nicotine-induced, axo-axonal interaction mechanism-mediated neurogenic dilation of the basilar arteries. Chronic abuse of these drugs, therefore, may interfere with normal sympathetic-parasympathetic interaction mechanism resulting in diminished neurogenic vasodilation and, possibly, normal blood flow in the brainstem. - Highlights: • Ketamine/amphetamines inhibit nicotine-induced cerebral neurogenic vasdilation. • Ketamine/amphetamines block cerebral perivascular sympathetic nAChR-mediated current. • The inhibitory potency is ketamine > D-amphetamine > methamphetamine > OH-amphetamine.« less

Effects of ketamine administration on mTOR and reticulum stress signaling pathways in the brain after the infusion of rapamycin into prefrontal cortex.

PubMed

Abelaira, Helena M; Réus, Gislaine Z; Ignácio, Zuleide M; Dos Santos, Maria Augusta B; de Moura, Airam B; Matos, Danyela; Demo, Júlia P; da Silva, Júlia B I; Michels, Monique; Abatti, Mariane; Sonai, Beatriz; Dal Pizzol, Felipe; Carvalho, André F; Quevedo, João

2017-04-01

Recent studies show that activation of the mTOR signaling pathway is required for the rapid antidepressant actions of glutamate N-methyl-D-aspartate (NMDA) receptor antagonists. A relationship between mTOR kinase and the endoplasmic reticulum (ER) stress pathway, also known as the unfolded protein response (UPR) has been shown. We evaluate the effects of ketamine administration on the mTOR signaling pathway and proteins of UPR in the prefrontal cortex (PFC), hippocampus, amygdala and nucleus accumbens, after the inhibiton of mTOR signaling in the PFC. Male adult Wistar rats received pharmacological mTOR inhibitor, rapamycin (0.2 nmol), or vehicle into the PFC and then a single dose of ketamine (15 mg/kg, i.p.). The immunocontent of mTOR, eukaryotic initiation factor 4E-binding protein 1 (4E-BP1), eukaryotic elongation factor 2 kinase (eEF2K) homologous protein (CHOP), PKR-like ER kinase (PERK) and inositol-requiring enzyme 1 (IRE1) - alpha were determined in the brain. The mTOR levels were reduced in the rapamycin group treated with saline and ketamine in the PFC; p4EBP1 levels were reduced in the rapamycin group treated with ketamine in the PFC and nucleus accumbens; the levels of peEF2K were increased in the PFC in the vehicle group treated with ketamine and reduced in the rapamycin group treated with ketamine. The PERK and IRE1-alpha levels were decreased in the PFC in the rapamycin group treated with ketamine. Our results suggest that mTOR signaling inhibition by rapamycin could be involved, at least in part, with the mechanism of action of ketamine; and the ketamine antidepressant on ER stress pathway could be also mediated by mTOR signaling pathway in certain brain structures. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ketamine, a Clinically Used Anesthetic, Inhibits Vascular Smooth Muscle Cell Proliferation via PP2A-Activated PI3K/Akt/ERK Inhibition

PubMed Central

Chang, Yi; Li, Jiun-Yi; Jayakumar, Thanasekaran; Hung, Shou-Huang; Lee, Wei-Cheng; Manubolu, Manjunath; Sheu, Joen-Rong; Hsu, Ming-Jen

2017-01-01

Abnormal proliferation of vascular smooth muscle cells (VSMCs) gives rise to major pathological processes involved in the development of cardiovascular diseases. The use of anti-proliferative agents for VSMCs offers potential for the treatment of vascular disorders. Intravenous anesthetics are firmly established to have direct effects on VSMCs, resulting in modulation of blood pressure. Ketamine has been used for many years in the intensive care unit (ICU) for sedation, and has recently been considered for adjunctive therapy. In the present study, we investigated the effects of ketamine on platelet-derived growth factor BB (PDGF-BB)-induced VSMC proliferation and the associated mechanism. Ketamine concentration-dependently inhibited PDGF-BB-induced VSMC proliferation without cytotoxicity, and phosphatidylinositol 3-kinase (PI3K) and extracellular signal-regulated protein kinase (ERK) inhibitors, LY294002 and PD98059, respectively, have similar inhibitory effects. Ketamine was shown to attenuate PI3K, Akt, and ERK1/2 phosphorylation induced by PDGF-BB. Okadaic acid, a selective protein phosphatase 2A (PP2A) inhibitor, significantly reversed ketamine-mediated PDGF-BB-induced PI3K, Akt, and ERK1/2 phosphorylation; a transfected protein phosphatse 2a (pp2a) siRNA reversed Akt and ERK1/2 phosphorylation; and 3-O-Methyl-sphingomyeline (3-OME), an inhibitor of sphingomyelinase, also significantly reversed ERK1/2 phosphorylation. Moreover, ketamine alone significantly inhibited tyrosine phosphorylation and demethylation of PP2A in a concentration-dependent manner. In addition, the pp2a siRNA potently reversed the ketamine-activated catalytic subunit (PP2A-C) of PP2A. These results provide evidence of an anti-proliferating effect of ketamine in VSMCs, showing activation of PP2A blocks PI3K, Akt, and ERK phosphorylation that subsequently inhibits the proliferation of VSMCs. Thus, ketamine may be considered a potential effective therapeutic agent for reducing atherosclerotic process by blocking the proliferation of VSMCs. PMID:29186909

Ketamine, a Clinically Used Anesthetic, Inhibits Vascular Smooth Muscle Cell Proliferation via PP2A-Activated PI3K/Akt/ERK Inhibition.

PubMed

Chang, Yi; Li, Jiun-Yi; Jayakumar, Thanasekaran; Hung, Shou-Huang; Lee, Wei-Cheng; Manubolu, Manjunath; Sheu, Joen-Rong; Hsu, Ming-Jen

2017-11-27

Abnormal proliferation of vascular smooth muscle cells (VSMCs) gives rise to major pathological processes involved in the development of cardiovascular diseases. The use of anti-proliferative agents for VSMCs offers potential for the treatment of vascular disorders. Intravenous anesthetics are firmly established to have direct effects on VSMCs, resulting in modulation of blood pressure. Ketamine has been used for many years in the intensive care unit (ICU) for sedation, and has recently been considered for adjunctive therapy. In the present study, we investigated the effects of ketamine on platelet-derived growth factor BB (PDGF-BB)-induced VSMC proliferation and the associated mechanism. Ketamine concentration-dependently inhibited PDGF-BB-induced VSMC proliferation without cytotoxicity, and phosphatidylinositol 3-kinase (PI3K) and extracellular signal-regulated protein kinase (ERK) inhibitors, LY294002 and PD98059, respectively, have similar inhibitory effects. Ketamine was shown to attenuate PI3K, Akt, and ERK1/2 phosphorylation induced by PDGF-BB. Okadaic acid, a selective protein phosphatase 2A (PP2A) inhibitor, significantly reversed ketamine-mediated PDGF-BB-induced PI3K, Akt, and ERK1/2 phosphorylation; a transfected protein phosphatse 2a ( pp2a ) siRNA reversed Akt and ERK1/2 phosphorylation; and 3-O-Methyl-sphingomyeline (3-OME), an inhibitor of sphingomyelinase, also significantly reversed ERK1/2 phosphorylation. Moreover, ketamine alone significantly inhibited tyrosine phosphorylation and demethylation of PP2A in a concentration-dependent manner. In addition, the pp2a siRNA potently reversed the ketamine-activated catalytic subunit (PP2A-C) of PP2A. These results provide evidence of an anti-proliferating effect of ketamine in VSMCs, showing activation of PP2A blocks PI3K, Akt, and ERK phosphorylation that subsequently inhibits the proliferation of VSMCs. Thus, ketamine may be considered a potential effective therapeutic agent for reducing atherosclerotic process by blocking the proliferation of VSMCs.

Adverse Events With Ketamine Versus Ketofol for Procedural Sedation on Adults: A Double-blind, Randomized Controlled Trial.

PubMed

Lemoel, Fabien; Contenti, Julie; Giolito, Didier; Boiffier, Mathieu; Rapp, Jocelyn; Istria, Jacques; Fournier, Marc; Ageron, François-Xavier; Levraut, Jacques

2017-12-01

The goal of our study was to compare the frequency and severity of recovery reactions between ketamine and ketamine-propofol 1:1 admixture ("ketofol"). We performed a multicentric, randomized, double-blind trial in which adult patients received emergency procedural sedations with ketamine or ketofol. Our primary outcome was the proportion of unpleasant recovery reactions. Other outcomes were frequency of interventions required by these recovery reactions, rates of respiratory or hemodynamic events, emesis, and satisfaction of patients as well as providers. A total of 152 patients completed the study, 76 in each arm. Compared with ketamine, ketofol determined a 22% reduction in recovery reactions incidence (p < 0.01) and less clinical and pharmacologic interventions required by these reactions. There was no serious adverse event in both groups. Rates in hemodynamic or respiratory events as well as satisfaction scores were similar. Significantly fewer patients experienced emesis with ketofol, with a threefold reduction in incidence compared with ketamine. We found a significant reduction in recovery reactions and emesis frequencies among adult patients receiving emergency procedural sedations with ketofol, compared with ketamine. © 2017 by the Society for Academic Emergency Medicine.

Performance on a probabilistic inference task in healthy subjects receiving ketamine compared with patients with schizophrenia

PubMed Central

Almahdi, Basil; Sultan, Pervez; Sohanpal, Imrat; Brandner, Brigitta; Collier, Tracey; Shergill, Sukhi S; Cregg, Roman; Averbeck, Bruno B

2012-01-01

Evidence suggests that some aspects of schizophrenia can be induced in healthy volunteers through acute administration of the non-competitive NMDA-receptor antagonist, ketamine. In probabilistic inference tasks, patients with schizophrenia have been shown to ‘jump to conclusions’ (JTC) when asked to make a decision. We aimed to test whether healthy participants receiving ketamine would adopt a JTC response pattern resembling that of patients. The paradigmatic task used to investigate JTC has been the ‘urn’ task, where participants are shown a sequence of beads drawn from one of two ‘urns’, each containing coloured beads in different proportions. Participants make a decision when they think they know the urn from which beads are being drawn. We compared performance on the urn task between controls receiving acute ketamine or placebo with that of patients with schizophrenia and another group of controls matched to the patient group. Patients were shown to exhibit a JTC response pattern relative to their matched controls, whereas JTC was not evident in controls receiving ketamine relative to placebo. Ketamine does not appear to promote JTC in healthy controls, suggesting that ketamine does not affect probabilistic inferences. PMID:22389244

Studies of Circulatory and Metabolic Changes during Ketamine Narcosis,

DTIC Science & Technology

1985-03-13

Braun, U., Hensel, I., Kettler, D., Lohr, B.: The effects of methoxyflurane , halothane, dipiritramide, barbiturate and ketamine on the total oxygen...narcosis caus- ed by ether, halothane, methoxyflurane , ketamine and piritranide, as well as neuroleptanalgesia. Lecture at the XIIth. General Con

Acute administration of ketamine in rats increases hippocampal BDNF and mTOR levels during forced swimming test

PubMed Central

Hu, Yi-Min; Zhou, Zhi-Qiang; Zhang, Guang-Fen

2013-01-01

Introduction Previous studies have shown that a single sub-anesthetic dose of ketamine exerts fast-acting antidepressant effects in patients and in animal models of depression. However, the underlying mechanisms are not totally understood. This study aims to investigate the effects of acute administration of different doses of ketamine on the immobility time of rats in the forced swimming test (FST) and to determine levels of hippocampal brain-derived neurotrophic factor (BDNF) and mammalian target of rapamycin (mTOR). Methods Forty male Wistar rats weighing 180–220 g were randomly divided into four groups (n = 10 each): group saline and groups ketamine 5, 10, and 15 mg/kg. On the first day, all animals were forced to swim for 15 min. On the second day ketamine (5, 10, and 15 mg/kg, respectively) was given intraperitoneally, at 30 min before the second episode of the forced swimming test. Immobility times of the rats during the forced swimming test were recorded. The animals were then decapitated. The hippocampus was harvested for determination of BDNF and mTOR levels. Results Compared with group saline, administration of ketamine at a dose of 5, 10, and 15 mg/kg decreased the duration of immobility (P < 0.05 for all doses). Ketamine at doses of both 10 and 15 mg/kg showed a significant increase in the expression of hippocampal BDNF (P < 0.05 for both doses). Ketamine given at doses of 5, 10, and 15 mg/kg showed significant increases in relative levels of hippocampal p-mTOR (P < 0.05 for all doses) Conclusion The antidepressant effect of ketamine might be related to the increased expression of BDNF and mTOR in the hippocampus of rats. PMID:22970723

Acute administration of ketamine in rats increases hippocampal BDNF and mTOR levels during forced swimming test.

PubMed

Yang, Chun; Hu, Yi-Min; Zhou, Zhi-Qiang; Zhang, Guang-Fen; Yang, Jian-Jun

2013-03-01

Previous studies have shown that a single sub-anesthetic dose of ketamine exerts fast-acting antidepressant effects in patients and in animal models of depression. However, the underlying mechanisms are not totally understood. This study aims to investigate the effects of acute administration of different doses of ketamine on the immobility time of rats in the forced swimming test (FST) and to determine levels of hippocampal brain-derived neurotrophic factor (BDNF) and mammalian target of rapamycin (mTOR). Forty male Wistar rats weighing 180-220 g were randomly divided into four groups (n = 10 each): group saline and groups ketamine 5, 10, and 15 mg/kg. On the first day, all animals were forced to swim for 15 min. On the second day ketamine (5, 10, and 15 mg/kg, respectively) was given intraperitoneally, at 30 min before the second episode of the forced swimming test. Immobility times of the rats during the forced swimming test were recorded. The animals were then decapitated. The hippocampus was harvested for determination of BDNF and mTOR levels. Compared with group saline, administration of ketamine at a dose of 5, 10, and 15 mg/kg decreased the duration of immobility (P < 0.05 for all doses). Ketamine at doses of both 10 and 15 mg/kg showed a significant increase in the expression of hippocampal BDNF (P < 0.05 for both doses). Ketamine given at doses of 5, 10, and 15 mg/kg showed significant increases in relative levels of hippocampal p-mTOR (P < 0.05 for all doses) The antidepressant effect of ketamine might be related to the increased expression of BDNF and mTOR in the hippocampus of rats.

Inhibition of the L-arginine-nitric oxide pathway mediates the antidepressant effects of ketamine in rats in the forced swimming test.

PubMed

Zhang, Guang-Fen; Wang, Nan; Shi, Jin-Yun; Xu, Shi-Xia; Li, Xiao-Min; Ji, Mu-Huo; Zuo, Zhi-Yi; Zhou, Zhi-Qiang; Yang, Jian-Jun

2013-09-01

Converging evidence shows that the acute administration of a sub-anaesthetic dose ketamine produces fast-acting and robust antidepressant properties in patients suffering from major depressive disorder. However, the underlying mechanisms have not been fully elucidated. The present study aimed to investigate the role of the L-arginine-nitric oxide pathway in the antidepressant effects of ketamine in rats performing the forced swimming test (FST). Ketamine (10 mg/kg) significantly decreased immobility times in the FST and the activities of total nitric oxide synthases (T-NOS), inducible NOS (iNOS), and endothelial NOS (eNOS) in the rat hippocampus. Interestingly, the plasma activities of T-NOS, iNOS, and eNOS increased after administration of ketamine. Furthermore, the activities of neuronal NOS (nNOS) did not change significantly in either the hippocampus or plasma after ketamine administration. The antidepressant effects of ketamine were prevented by pre-treatment with l-arginine (750 mg/kg). Pre-treatment with the NOS inhibitor L-NG-nitroarginine methyl ester at a sub-antidepressant dose of 50 mg/kg and ketamine at a sub-antidepressant dose of 3 mg/kg reduced immobility time in the FST compared to treatment with either drug alone. None of the drugs affected crossing and rearing scores in the open field test. These results suggest that the L-arginine-nitric oxide pathway is involved in the antidepressant effects of ketamine observed in rats in the FST and this involvement is characterised by the inhibition of brain T-NOS, iNOS, and eNOS activities. Copyright © 2013 Elsevier Inc. All rights reserved.

Rationale and design of a multicenter randomized clinical trial with memantine and dextromethorphan in ketamine-responder patients.

PubMed

Pickering, Gisèle; Pereira, Bruno; Morel, Véronique; Tiberghien, Florence; Martin, Elodie; Marcaillou, Fabienne; Picard, Pascale; Delage, Noémie; de Montgazon, Géraldine; Sorel, Marc; Roux, Delphine; Dubray, Claude

2014-07-01

The N-methyl-D-aspartate receptor plays an important role in central sensitization of neuropathic pain and N-methyl-D-aspartate receptor antagonists, such as ketamine, memantine and dextromethorphan may be used for persistent pain. However, ketamine cannot be repeated too often because of its adverse events. A drug relay would be helpful in the outpatient to postpone or even cancel the next ketamine infusion. This clinical trial evaluates if memantine and/or dextromethorphan given as a relay to ketamine responders may maintain or induce a decrease of pain intensity and have a beneficial impact on cognition and quality of life. This trial is a multi-center, randomized, controlled and single-blind clinical study (NCT01602185). It includes 60 ketamine responder patients suffering from neuropathic pain. They are randomly allocated to memantine, dextromethorphan or placebo. After ketamine infusion, 60 patients received either memantine (maximal dose 20 mg/day), or dextromethorphan (maximal dose 90 mg/day), or placebo for 12 weeks. The primary endpoint is pain measured on a (0-10) Numeric Rating Scale 1 month after inclusion. Secondary outcomes include assessment of neuropathic pain, sleep, quality of life, anxiety/depression and cognitive function at 2 and 3 months. Data analysis is performed using mixed models and the tests are two-sided, with a type I error set at α=0.05. This study will explore if oral memantine and/or dextromethorphan may be a beneficial relay in ketamine responders and may diminish ketamine infusion frequency. Preservation of cognitive function and quality of life is also a central issue that will be analyzed in these vulnerable patients. Copyright © 2014. Published by Elsevier Inc.

The use of sub-anesthetic intravenous ketamine and adjuvant dexmedetomidine when treating acute pain from CRPS.

PubMed

Nama, Sharanya; Meenan, Daniel R; Fritz, William T

2010-01-01

Complex regional pain syndrome (CRPS) is a pain condition of the extremities that presents with pain and allodynia, decreased range of motion, swelling and skin changes. There are 2 forms of CRPS - Type I which does not have demonstrable nerve lesions and Type 2, which has evidence of obvious nerve damage. Management of refractory CRPS has been challenging. Some studies have revealed that the N-methyl-D-aspartic acid receptor (NMDAR) may be involved in the etiology of the pain in CRPS and perhaps that a NMDA receptor antagonist like ketamine is a potential treatment for CRPS. However, the side effect profile of ketamine is concerning, and limiting the adverse effects of the drug is beneficial. Dexmedetomidine is an alpha 2 agonist similar to clonidine with analgesic properties that can be used in combination with ketamine to provide additional analgesia in CRPS. This case describes the treatment of acute pain symptoms from Chronic Regional Pain Syndrome-Type 1 (CRPS-1) with sub-anesthetic intravenous infusion of ketamine with adjunct dexmedetomidine. A 47-year-old female patient presented with severe pain, burning and allodynia from CRPS-1 refractory to conventional therapy. She was then admitted to a monitored bed, received a sub-anesthetic intravenous infusion of ketamine with adjunct dexmedetomidine for 19 hours and subsequently discharged with complete resolution of her pain and associated symptoms. Here, the synergistic effect of the ketamine and dexmedetomidine together is shown to provide excellent symptom relief while decreasing the total ketamine administered. The combination minimized unwanted side effects and eliminated the need for intensive care unit admission secondary to anesthetic doses of ketamine.

Ketamine facilitates extinction of avoidance behavior and enhances synaptic plasticity in a rat model of anxiety vulnerability: Implications for the pathophysiology and treatment of anxiety disorders.

PubMed

Fortress, Ashley M; Smith, Ian M; Pang, Kevin C H

2018-05-08

Anxiety disorders and posttraumatic stress disorder (PTSD) share a common feature of pathological avoidance behavior. The Wistar Kyoto (WKY) rat has been used as a model of anxiety vulnerability, expressing a behaviorally inhibited temperament, acquiring avoidance behavior more rapidly and displaying extinction-resistant avoidance compared to Sprague Dawley (SD) rats. Subanesthetic levels of ketamine have gained attention as a rapid antidepressant in treatment-resistant depression. While traditional antidepressants are commonly used to treat anxiety disorders and PTSD, the therapeutic utility of ketamine for these disorders is much less understood. The hippocampus is critical for the actions of antidepressants, is a structure of implicated in anxiety disorders and PTSD, and is necessary for extinction of avoidance in SD rats. WKY rats have impaired hippocampal long-term potentiation (LTP), suggesting that persistent avoidance in WKY rats may be due to deficient hippocampal synaptic plasticity. In the present study, we hypothesized that ketamine would facilitate extinction of avoidance learning in WKY rats, and do so by enhancing hippocampal synaptic plasticity. As predicted, ketamine facilitated extinction of avoidance behavior in a subset of WKY rats (responders), with effects lasting at least three weeks. Additionally, LTP in these rats was enhanced by ketamine. Ketamine was not effective in facilitating avoidance extinction or in modifying LTP in WKY non-responders. The results suggest that subanesthetic levels of ketamine may be useful for treating anxiety disorders by reducing avoidance behaviors when combined with extinction conditions. Moreover, ketamine may have its long-lasting behavioral effects through enhancing hippocampal synaptic plasticity. Copyright © 2018. Published by Elsevier Ltd.

Effect of ketamine pretreatment for anaesthesia in patients undergoing percutaneous transluminal balloon angioplasty with continuous remifentanil infusion

PubMed Central

Jun, Na Hyung; Shim, Jae Kwang; Choi, Yong Sun; An, Seung Ho

2011-01-01

Background An appropriate level of sedation and pharmacological assist are essential during percutaneous transluminal balloon angioplasty (PTA). Ketamine provides good analgesia while preserving airway patency, ventilation, and cardiovascular stability with an opioid sparing effect suggesting that it would be ideal in combination with remifentanil and midazolam in spontaneously breathing patients. We evaluated the effect of a small dose of ketamine added to midazolam and remifentanil on analgesia/sedation for PTA procedures. Methods Sixty-four patients receiving PTA were enrolled. The Control group received midazolam 1.0 mg i.v. and continuous infusion of remifentanil 0.05 µg/kg/min. The Ketamine group received, in addition, an intravenous bolus of 0.5 mg/kg ketamine. Patients' haemodynamic data were monitored before remifentanil infusion, 5 min after remifentanil infusion, at 1, 3, 5, 30 min after incision, and at admission to the recovery room. Verbal numerical rating scales (VNRS) and sedation [OAA/S (Observer's Assessment of Alertness/Sedation)] scores were also recorded. Results The VNRS values at 1, 3, and 5 min after incision and OAA/S scores at 5 min after remifentanil infusion, and 1, 3, and 5 min after incision were lower in the Ketamine group than in the Control group. In the Control group, the VNRS value at 1 min after incision significantly increased and OAA/S values at 3, 5, and 30 min after incision significantly decreased compared to baseline values, while there were no significant changes in the ketamine group. Conclusions A small dose of ketamine as an adjunct sedative to the combination of midazolam and remifentanil produced a better quality of sedation and analgesia than without ketamine and provided stable respiration without cardiopulmonary deterioration. PMID:22110884

The correlation between ketamine and posttraumatic stress disorder in burned service members.

PubMed

McGhee, Laura L; Maani, Christopher V; Garza, Thomas H; Gaylord, Kathryn M; Black, Ian H

2008-02-01

Predisposing factors for posttraumatic stress disorder (PTSD) include experiencing a traumatic event, threat of injury or death, and untreated pain. Ketamine, an anesthetic, is used at low doses as part of a multimodal anesthetic regimen. However, since ketamine is associated with psychosomatic effects, there is a concern that ketamine may increase the risk of developing PTSD. This study investigated the prevalence of PTSD in Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) service members who were treated for burns in a military treatment center. The PTSD Checklist-Military (PCL-M) is a 17-question screening tool for PTSD used by the military. A score of 44 or higher is a positive screen for PTSD. The charts of all OIF/OEF soldiers with burns who completed the PCL-M screening tool (2002-2007) were reviewed to determine the number of surgeries received, the anesthetic regime used, including amounts given, the total body surface area burned, and injury severity score. Morphine equivalent units were calculated using standard dosage conversion factors. The prevalence of PTSD in patients receiving ketamine during their operation(s) was compared with patients not receiving ketamine. Of the 25,000 soldiers injured in OIF/OEF, United States Army Institute of Surgical Research received 603 burned casualties, of which 241 completed the PCL-M. Of those, 147 soldiers underwent at least one operation. Among 119 patients who received ketamine during surgery and 28 who did not; the prevalence of PTSD was 27% (32 of 119) versus 46% (13 of 28), respectively (p = 0.044). Contrary to expectations, patients receiving perioperative ketamine had a lower prevalence of PTSD than soldiers receiving no ketamine during their surgeries despite having larger burns, higher injury severity score, undergoing more operations, and spending more time in the ICU.

Comparison of different administration of ketamine and intravenous tramadol hydrochloride for postoperative pain relief and sedation after pediatric tonsillectomy.

PubMed

Yenigun, Alper; Et, Tayfun; Aytac, Sirin; Olcay, Betul

2015-01-01

Tonsillectomy is the oldest and most frequently performed surgical procedure practiced by ear, nose, and throat physicians. In this study, our aim was to compare the analgesic effects of peritonsillar, rectal, as well as intravenous infiltration of ketamine and intravenous tramadol hydrochloride infiltration for postoperative pain relief and sedation after tonsillectomy in children. This randomized controlled study evaluated the effects of peritonsillar, intravenous, and rectal infiltration of ketamine in children undergoing adenotonsillectomy. One hundred twenty children who were categorized under American Society of Anesthesiologists classes I to II were randomized to 4 groups of 30 members each. Group 1 received intravenous (IV) ketamine (0.5 mg/kg), group 2 received rectal ketamine (0.5 mg/kg), group 3 received local peritonsillar ketamine (2 mg/kg), and the control group received IV tramadol hydrochloride infiltration (2 mg/kg). Children's Hospital of Eastern Ontario Pain Scale scores and Wilson sedation scale were recorded at minutes 1, 15, 30, 60 as well as hours 2, 12, and 24 postoperatively. The patients were interviewed on the day after the surgery to assess the postoperative pain and sedation. All the routes of infiltration of ketamine were as effective as those of tramadol hydrochloride (P > 0.05). A statistically significant difference was observed between IV infiltrations and all groups during the assessments at hours 6 and 24. The analgesic efficacy of IV ketamine was found especially higher at hours 6 and 24 (P(6) = 0.045, P(24) = 0.011). Perioperative, low-dose IV, rectal, or peritonsillar ketamine infiltration provides efficient pain relief without any adverse effects in children who would undergo adenotonsillectomy.

Distinct retrosplenial cortex cell populations and their spike dynamics during ketamine-induced unconscious state.

PubMed

Fox, Grace E; Li, Meng; Zhao, Fang; Tsien, Joe Z

2017-01-01

Ketamine is known to induce psychotic-like symptoms, including delirium and visual hallucinations. It also causes neuronal damage and cell death in the retrosplenial cortex (RSC), an area that is thought to be a part of high visual cortical pathways and at least partially responsible for ketamine's psychotomimetic activities. However, the basic physiological properties of RSC cells as well as their response to ketamine in vivo remained largely unexplored. Here, we combine a computational method, the Inter-Spike Interval Classification Analysis (ISICA), and in vivo recordings to uncover and profile excitatory cell subtypes within layers 2&3 and 5&6 of the RSC in mice within both conscious, sleep, and ketamine-induced unconscious states. We demonstrate two distinct excitatory principal cell sub-populations, namely, high-bursting excitatory principal cells and low-bursting excitatory principal cells, within layers 2&3, and show that this classification is robust over the conscious states, namely quiet awake, and natural unconscious sleep periods. Similarly, we provide evidence of high-bursting and low-bursting excitatory principal cell sub-populations within layers 5&6 that remained distinct during quiet awake and sleep states. We further examined how these subtypes are dynamically altered by ketamine. During ketamine-induced unconscious state, these distinct excitatory principal cell subtypes in both layer 2&3 and layer 5&6 exhibited distinct dynamics. We also uncovered different dynamics of local field potential under various brain states in layer 2&3 and layer 5&6. Interestingly, ketamine administration induced high gamma oscillations in layer 2&3 of the RSC, but not layer 5&6. Our results show that excitatory principal cells within RSC layers 2&3 and 5&6 contain multiple physiologically distinct sub-populations, and they are differentially affected by ketamine.

Effects of GABA-B receptor positive modulator on ketamine-induced psychosis-relevant behaviors and hippocampal electrical activity in freely moving rats.

PubMed

Ma, Jingyi; Stan Leung, L

2017-10-01

Decreased GABA B receptor function is proposed to mediate some symptoms of schizophrenia. In this study, we tested the effect of CGP7930, a GABA B receptor positive allosteric modulator, on ketamine-induced psychosis-relevant behaviors and hippocampal electrical activity in behaving rats. Electrodes were bilaterally implanted into the hippocampus, and cannulae were placed into the lateral ventricles of Long-Evans rats. CGP7930 or vehicle was injected intraperitoneally (i.p.) or intracerebroventricularly (i.c.v.), alone or 15 min prior to ketamine (3 mg/kg, subcutaneous) injection. Paired click auditory evoked potentials in the hippocampus (AEP), prepulse inhibition (PPI), and locomotor activity were recorded before and after drug injection. CGP7930 at doses of 1 mg/kg (i.p.) prevented ketamine-induced deficit of PPI. CGP7930 (1 mg/kg i.p.) also prevented the decrease in gating of hippocampal AEP and the increase in hippocampal gamma (65-100 Hz) waves induced by ketamine. Unilateral i.c.v. infusion of CGP7930 (0.3 mM/1 μL) also prevented the decrease in gating of hippocampal AEP induced by ketamine. Ketamine-induced behavioral hyperlocomotion was suppressed by 5 mg/kg i.p. CGP7930. CGP7930 alone, without ketamine, did not significantly affect integrated PPI, locomotion, gating of hippocampal AEP, or gamma waves. CGP7930 (1 mg/kg i.p.) increased heterosynaptically mediated paired pulse depression in the hippocampus, a measure of GABA B receptor function in vivo. CGP7930 reduces the behavioral and electrophysiological disruptions induced by ketamine in animals, and the hippocampus may be one of the neural targets where CGP7930 exerts its actions.

Suppression of Methamphetamine Self-Administration by Ketamine Pre-treatment Is Absent in the Methylazoxymethanol (MAM) Rat Model of Schizophrenia.

PubMed

Ruda-Kucerova, Jana; Babinska, Zuzana; Stark, Tibor; Micale, Vincenzo

2017-07-01

Ketamine may prove to be a potential candidate in treating the widespread drug addiction/substance abuse epidemic among patients with schizophrenia. Clinical studies have shown ketamine to reduce cocaine and heroin cravings. However, the use of ketamine remains controversial as it may exacerbate the symptoms of schizophrenia. Therefore, the aim of this study is to characterize the effects of ketamine on drug addiction in schizophrenia using the methylazoxymethanol (MAM) acetate rat model on operant IV methamphetamine (METH) self-administration. MAM was administered intraperitoneally (22 mg/kg) on gestational day 17. Locomotor activity test and later IV self-administration (IVSA) were then performed in the male offspring followed by a period of forced abstinence and relapse of METH taking. After reaching stable intakes in the relapse phase, ketamine (5 mg/kg) was administered intraperitoneally 30 min prior to the self-administration session. As documented previously, the MAM rats showed a lack of habituation in the locomotor activity test but developed stable maintenance of METH self-administration with no difference in operant behaviour to control animals. Results show that ketamine treatment significantly reduced the METH intake in the control animals but not in MAM animals. Ketamine effect on METH self-administration may be explained by increased glutamatergic signalling in the prefrontal cortex caused by the N-methyl-D-aspartate antagonism and disinhibition of GABA interneurons which was shown to be impaired in the MAM rats. This mechanism may at least partly explain the clinically proven anti-craving potential of ketamine and allow development of more specific anti-craving medications with fewer risks.

Prolonged ketamine exposure induces increased activity of the GluN2B-containing N-methyl-d-aspartate receptor in the anterior cingulate cortex of neonatal rats.

PubMed

Kokane, Saurabh S; Gong, Kerui; Jin, Jianhui; Lin, Qing

2017-09-01

Ketamine is a commonly used anesthetic among pediatric patients due to its high efficacy. However, it has been demonstrated by several preclinical studies that, widespread accelerated programmed death of neurons (neuroapoptosis) occurs due to prolonged or repeated exposure to ketamine specifically in the neonatal brain. Therefore, an emphasis on understanding the molecular mechanisms underlying this selective vulnerability of the neonatal brain to ketamine-induced neuroapoptosis becomes important in order to identify potential therapeutic targets, which would help prevent or at least ameliorate this neuroapoptosis. In this study, we demonstrated that repeated ketamine administration (6 injections of 20mg/kg dose given over 12h time period) in neonatal (postnatal day 7; PND 7) Sprague-Dawley rats induced a progressive increase in N-methyl-d-aspartate receptor (NMDAR)-mediated excitatory postsynaptic currents (EPSCs) in the neurons of the anterior cingulate cortex (ACC) for up to 6h after the last ketamine dose. Specifically, we observed that the increased EPSCs were largely mediated by GluN2B-containing NMDARs in the neurons of the ACC. Along with increased synaptic transmission, there was also a significant increase in the expression of the GluN2B-containing NMDARs as well. Taken together, these results showed that after repeated exposure to ketamine, the synaptic transmission mediated by GluN2B-containing NMDARs was significantly increased in the neonatal brain. This was significant as it showed for the first time that ketamine had subunit-specific effects on GluN2B-containing NMDARs, potentially implicating the involvement of these subunits in the increased vulnerability of immature neurons of the neonatal brain to ketamine-induced neuroapoptosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Efficacy and safety of oral ketamine for the relief of intractable chronic pain: A retrospective 5-year study of 51 patients.

PubMed

Marchetti, F; Coutaux, A; Bellanger, A; Magneux, C; Bourgeois, P; Mion, G

2015-08-01

This work summarizes the efficiency, failures and adverse effects of oral administration of ketamine at home for intractable pain. This 5-year retrospective study involved testing ketamine by intravenous in-hospital administration, then a conversion to an oral route, or oral treatment directly administered at home. The daily intravenous dose was increased by steps of 0.5 mg/kg to attain an effective daily dose of 1.5-3.0 mg/kg. Pain was evaluated on a numeric scale from 0 to 10, and evidence of adverse effects was collected every day. The effective daily dose was delivered orally (three to four intakes). If effective, ketamine was continued for 3 months. Short infusions or direct oral treatment began with a 0.5-mg/kg dose, then the daily ketamine dose was increased in 15- to 20-mg increments. Among 55 cases (51 patients, neuropathic pain 60%), the mean effective oral dose was 2 mg/kg. Ketamine was effective in 24 patients (44%, mean pain reduction 67 ± 17%), partially effective in 20% (mean pain reduction 30 ± 11%), with a mean opioid sparing of 63 ± 32%, and failure in 22%. Half of the patients experienced adverse effects, but only eight had to stop treatment. For patients with opioid therapy, failure of ketamine was less frequent (7% vs. 36%; p < 0.02), with fewer adverse effects (33% vs. 68%; p < 0.01). Pain was reduced or abolished in two-thirds of patients under ketamine therapy; ketamine was effective for patients taking opioids and resulted in few adverse effects. © 2014 European Pain Federation - EFIC®

An effective dose of ketamine for eliminating pain during injection of propofol: a dose response study.

PubMed

Wang, M; Wang, Q; Yu, Y Y; Wang, W S

2013-09-01

Ketamine can completely eliminate pain associated with propofol injection. However, the effective dose of ketamine to eliminate propofol injection pain has not been determined. The purpose of this study was to determine the effective dose of ketamine needed to eliminate pain in 50% and 95% of patients (ED50 and ED95, respectively) during propofol injections. This study was conducted in a double-blinded fashion and included 50 patients scheduled for elective gynecological laparoscopy under general anesthesia. The initial dose of ketamine used in the first patient was 0.25mg/kg. The dosing modifications were in increments or decrements of 0.025 mg/kg. Ketamine was administered 15 seconds before injecting propofol (2.5mg/kg), which was injected at a rate of 1mL/s. Patients were asked to rate their pain during propofol injection every 5s econds using a 0-3 pain scale. The highest pain score was recorded. The ED50, ED95 and 95% confidence intervals (CI) were determined by probit analyses. The dose of ketamine ranged from 0.175 to 0.275 mg/kg. The ED50 and ED95 of ketamine for eliminating pain during propofol injection were 0.227 mg/kg and 0.283 mg/kg, respectively (95%CI: 0.211-0.243 mg/kg and 0.26-0.364 mg/kg, respectively). Ketamine at an approximate dose of 0.3mg/kg was effective in eliminating pain during propofol injection. Copyright © 2013 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

Ketamine for pain management in France, an observational survey.

PubMed

Martinez, Valeria; Derivaux, Benoit; Beloeil, Helene

2015-12-01

Before updating the French guidelines on postoperative pain treatment in 2015, the Pain Committee of the French Society of Anaesthesiology and Intensive Care (SFAR) conducted a survey on the medical use of ketamine in France. An online questionnaire was nationally distributed to members of SFAR, the French Pain Society (SFETD) and the French Society of Emergency Medicine (SFMU). The questionnaire included questions on demographic data, the type of patients for whom ketamine was prescribed, the doses used, the side effects and safety measures associated with the administration of ketamine. A total of 1388 questionnaires were analysed. Ninety-two percent of the responders declared that they used ketamine. Ketamine was widely used as anti-hyperalgesic medication but the modalities of administration and the doses varied greatly and were not in accordance with the guidelines. Despite the lack of evidence and guidelines, ketamine has also been used to treat acute and chronic pain. Doses, duration and localization of the patients during administration have varied greatly. Psychedelic effects and hallucinations are the most feared side effects. In terms of monitoring during ketamine infusion, 15% of physicians declared that no monitoring was necessary while 59%, 55%, 59% and 77% monitored heart rate, SpO2, blood pressure and level of consciousness, respectively. Anaesthesiologists have integrated the benefit of ketamine in preventing hyperalgesia but there is no consensus on doses and duration. For other indications (acute and chronic pain treatment), toxicity and the absence of significant benefit call for guidelines from scientific societies. Copyright © 2015 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier Masson SAS. All rights reserved.

Effect of Rifampicin on S-ketamine and S-norketamine Plasma Concentrations in Healthy Volunteers after Intravenous S-ketamine Administration

PubMed Central

Noppers, Ingeborg; Olofsen, Erik; Niesters, Marieke; Aarts, Leon; Mooren, René; Dahan, Albert; Kharasch, Evan; Sarton, Elise

2012-01-01

Background Low-dose ketamine is used as analgesic for acute and chronic pain. It is metabolized in the liver to norketamine via cytochrome P450 enzymes. There are few human data on the involvement of CYP enzymes on the elimination of norketamine and its possible contribution to analgesic effect. The aim of this study was to investigate the effect of cytochrome P450 enzyme induction by rifampicin on the pharmacokinetics of S-ketamine and its major metabolite, S-norketamine, in healthy volunteers. Methods Twenty healthy male subjects received 20 mg/70kg/h (n = 10) or 40 mg/70kg/h (n = 10) intravenous S-ketamine for 2-h following either 5 days of oral rifampicin (once daily 600 mg) or placebo treatment. During and 3-h following drug infusion arterial plasma concentrations of S-ketamine and S-norketamine were obtained at regular intervals. The data were analyzed with a compartmental pharmacokinetic model consisting of three compartments for S-ketamine, three sequential metabolism compartments and two S-norketamine compartments using the statistical package NONMEM version VII. Results Rifampcin caused a 10% and 50% reduction in the area-under-the-curve of the plasma concentrations of S-ketamine and S-norketamine, respectively. The compartmental analysis indicated a 13% and 200% increase in S-ketamine and S-norketamine elimination from their respective central compartments by rifampicin. Conclusions A novel observation is the large effect of rifampicin on S-norketamine concentrations and indicates that rifampicin induces the elimination of S-ketamine’s metabolite, S-norketamine, probably via induction of the CYP3A4 and/or CYP2B6 enzymes. PMID:21508826

A systematic review and meta-analysis of ketamine for the prevention of persistent post-surgical pain.

PubMed

McNicol, E D; Schumann, R; Haroutounian, S

2014-11-01

While post-operative pain routinely resolves, persistent post-surgical pain (PPSP) is common in certain surgeries; it causes disability, lowers quality of life and has economic consequences. The objectives of this systematic review and meta-analysis were to evaluate the effectiveness of ketamine in reducing the prevalence and severity of PPSP and to assess safety associated with its use. We searched the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE through December 2012 for articles in any language. We included randomized, controlled trials in adults in which ketamine was administered perioperatively via any route. Seventeen studies, the majority of which administered ketamine intravenously, met all inclusion criteria. The overall risk of developing PPSP was not significantly reduced at any time point in the ketamine group vs. placebo, nor did comparisons of pain severity scores reach statistical significance. Sensitivity analysis of exclusively intravenous ketamine studies included in this meta-analysis demonstrated statistically significant reductions in risk of developing PPSP at 3 and 6 months (P = 0.01 and P = 0.04, respectively). Adverse event rates were similar between ketamine and placebo groups. The study data from our review are heterogeneous and demonstrate efficacy of intravenously administered ketamine only in comparison with placebo. Highly variable timing and dosing of ketamine in these studies suggest that no unifying effective regimen has emerged. Future research should focus on clinically relevant outcomes, should stratify patients with pre-existing pain and possible central sensitization and should enroll sufficiently large numbers to account for loss to follow-up in long-term studies. © 2014 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Ketamine use for rapid sequence intubation in Australian and New Zealand emergency departments from 2010 to 2015: A registry study.

PubMed

Ferguson, Ian; Alkhouri, Hatem; Fogg, Toby; Aneman, Anders

2018-06-11

This study aimed to quantify the proportion of patients undergoing rapid sequence intubation using ketamine in Australian and New Zealand EDs between 2010 and 2015. The Australian and New Zealand Emergency Department Airway Registry is a multicentre airway registry prospectively capturing data from 43 sites. Data on demographics and physiology, the attending staff and indication for intubation were recorded. The primary outcome was the annual percentage of patients intubated with ketamine. A logistic regression analysis was conducted to evaluate the factors associated with ketamine use. A total of 4658 patients met inclusion criteria. The annual incidence of ketamine use increased from 5% to 28% over the study period (P < 0.0001). In the logistic regression analysis, the presence of an emergency physician as a team leader was the strongest predictor of ketamine use (odds ratio [OR] 1.83, 95% confidence interval [CI] 1.44-2.34). The OR for an increase in one point on the Glasgow Coma Scale was 1.10 (95% CI 1.07-1.12), whereas an increase of 1 mmHg of systolic blood pressure had an OR of 0.98 (95% CI 0.98-0.99). Intubation occurring in a major referral hospital had an OR of 0.68 (95% CI 0.56-0.82), while trauma conferred an OR of 1.38 (95% CI 1.25-1.53). Ketamine use increased between 2010 and 2015. Lower systolic blood pressure, the presence of an emergency medicine team leader, trauma and a higher Glasgow Coma Scale were associated with increased odds of ketamine use. Intubation occurring in a major referral centre was associated with lower odds of ketamine use. © 2018 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

CD-1 and Balb/cJ mice do not show enduring antidepressant-like effects of ketamine in tests of acute antidepressant efficacy.

PubMed

Bechtholt-Gompf, Anita J; Smith, Karen L; John, Catherine S; Kang, Hannah H; Carlezon, William A; Cohen, Bruce M; Ongür, Dost

2011-06-01

In patients, ketamine is a fast-acting antidepressant that can induce long-lasting symptom relief. Similar rapid effects have been reported in rodents, but reports of lasting effects are limited. We sought to extend past findings by examining dose-response curves that overlap with the individual doses previously reported to induce lasting effects in rodents and determining whether effects generalize to the tail suspension test (TST) and Balb/cJ mice. Using common tests of antidepressant efficacy we first confirmed our ability to detect the effects of desipramine, a well-characterized antidepressant drug. Next, we sought to determine whether two non-competitive NMDA antagonists, ketamine and MK-801, had long-lasting antidepressant-like effects in CD-1 mice, a strain that has often been used to demonstrate the short-term antidepressant-like effects of ketamine. Finally, we examined the short- and long-term effects of ketamine in a mouse strain that is more sensitive to antidepressant-like effects, Balb/cJ mice. In CD-1 mice, desipramine treatment yielded significant short-term antidepressant-like effects in the TST and the forced swimming test (FST). However, no significant enduring effects of ketamine or MK-801 were observed 1 week later. Short-term effects of ketamine in the TST were observed in Balb/cJ mice, but lasting effects were absent 1 week later. Although the TST and FST have been widely used to detect antidepressant-like effects in mice, they do not appear to be sensitive to long-lasting antidepressant-like effects of ketamine in mice and, therefore, do not model the therapeutic effects of ketamine that have been reported in humans with major depression.

Temporal Dynamics of Antidepressant Ketamine Effects on Glutamine Cycling Follow Regional Fingerprints of AMPA and NMDA Receptor Densities.

PubMed

Li, Meng; Demenescu, Liliana Ramona; Colic, Lejla; Metzger, Coraline Danielle; Heinze, Hans-Jochen; Steiner, Johann; Speck, Oliver; Fejtova, Anna; Salvadore, Giacomo; Walter, Martin

2017-05-01

The anterior cingulate cortex (ACC) has shown decreased glutamate levels in patients with major depressive disorder. Subanesthetic doses of ketamine were repeatedly shown to improve depressive symptoms within 24 h after infusion and this antidepressant effect was attributed to increased α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) throughput. To elucidate ketamine's mechanism of action, we tested whether the clinical time course of the improvement is mirrored by the change of glutamine/glutamate ratio and if such effects show a regional and temporal specificity in two distinct subdivisions of ACC with different AMPA/N-methyl-D-aspartate receptor profiles. In a double-blind, placebo-controlled intravenous infusion study of ketamine, we measured glutamate and glutamine in the pregenual ACC (pgACC) and the anterior midcingulate cortex at 1 and 24 h post infusion with magnetic resonance spectroscopy at 7 T. A significant interaction of time, region, and treatment was found for the glutamine/glutamate ratios (placebo, n=14; ketamine, n=12). Post-hoc analyses revealed that the glutamine/glutamate ratio increased significantly in the ketamine group, compared with placebo, specifically in the pgACC after 24 h. The glutamine/glutamate increase in the pgACC caused by ketamine at 24 h post infusion was reproduced in an enlarged sample (placebo, n=24; ketamine, n=20). Our results support a significant temporal and regional response in glutamine/glutamate ratios to a single subanesthetic dose of ketamine, which mirrors the time course of the antidepressant response and reversal of the molecular deficits in patients and which may be associated with the histoarchitectonical receptor fingerprints of the ACC subregions.

Temporal Dynamics of Antidepressant Ketamine Effects on Glutamine Cycling Follow Regional Fingerprints of AMPA and NMDA Receptor Densities

PubMed Central

Li, Meng; Demenescu, Liliana Ramona; Colic, Lejla; Metzger, Coraline Danielle; Heinze, Hans-Jochen; Steiner, Johann; Speck, Oliver; Fejtova, Anna; Salvadore, Giacomo; Walter, Martin

2017-01-01

The anterior cingulate cortex (ACC) has shown decreased glutamate levels in patients with major depressive disorder. Subanesthetic doses of ketamine were repeatedly shown to improve depressive symptoms within 24 h after infusion and this antidepressant effect was attributed to increased α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) throughput. To elucidate ketamine's mechanism of action, we tested whether the clinical time course of the improvement is mirrored by the change of glutamine/glutamate ratio and if such effects show a regional and temporal specificity in two distinct subdivisions of ACC with different AMPA/N-methyl-D-aspartate receptor profiles. In a double-blind, placebo-controlled intravenous infusion study of ketamine, we measured glutamate and glutamine in the pregenual ACC (pgACC) and the anterior midcingulate cortex at 1 and 24 h post infusion with magnetic resonance spectroscopy at 7 T. A significant interaction of time, region, and treatment was found for the glutamine/glutamate ratios (placebo, n=14; ketamine, n=12). Post-hoc analyses revealed that the glutamine/glutamate ratio increased significantly in the ketamine group, compared with placebo, specifically in the pgACC after 24 h. The glutamine/glutamate increase in the pgACC caused by ketamine at 24 h post infusion was reproduced in an enlarged sample (placebo, n=24; ketamine, n=20). Our results support a significant temporal and regional response in glutamine/glutamate ratios to a single subanesthetic dose of ketamine, which mirrors the time course of the antidepressant response and reversal of the molecular deficits in patients and which may be associated with the histoarchitectonical receptor fingerprints of the ACC subregions. PMID:27604568

Serum BDNF as a peripheral biomarker of treatment-resistant depression and the rapid antidepressant response: A comparison of ketamine and ECT.

PubMed

Allen, A P; Naughton, M; Dowling, J; Walsh, A; Ismail, F; Shorten, G; Scott, L; McLoughlin, D M; Cryan, J F; Dinan, T G; Clarke, G

2015-11-01

Ketamine is associated with rapid antidepressant efficacy but the biological mechanisms underpinning this effect are unclear. Serum brain-derived neurotrophic factor (sBDNF) is a potential circulating biomarker of treatment-resistant depression (TRD) and ketamine response but it is unclear if this is a common target of both ketamine and electroconvulsive therapy (ECT), the current gold standard for TRD. Moreover, the impact of multiple ketamine infusions on sBDNF has not yet been established. Thirty five TRD patients with a current DSM-IV diagnosis of recurrent depressive disorder received up to 12 ECT sessions (N=17) or up to three intravenous infusions of low-dose (0.5mg/kg) ketamine (N=18). Blood samples were taken over the course of the study for assessment of sBDNF. Symptom severity and response were monitored using the 17-item Hamilton Depression Rating Scale (HDRS). sBDNF was assessed in 20 healthy controls to allow comparison with TRD patients. As expected, sBDNF was lower in TRD patients at baseline compared to healthy controls. Ketamine and ECT treatment were both associated with significant reductions in depressive symptoms. However, sBDNF was significantly elevated only at one week following the first ketamine infusion in those classified as responders one week later. sBDNF was not elevated following subsequent infusions. ECT reduced depressive symptoms, as expected, but was not associated with an enhancement in BDNF. Patients continued with their psychotropic medications throughout this trial. SBDNF normalisation does not appear to be a prerequisite for symptomatic improvement in TRD following ketamine or ECT treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

Post-electroconvulsive therapy recovery and reorientation time with methohexital and ketamine: a randomized, longitudinal cross-over design trial

PubMed Central

Yen, Tony; Khafaja, Mohamad; Lam, Nicholas; Crumbacher, James; Schrader, Ronald; Rask, John; Billstrand, Mary; Rothfork, Jacob; Abbott, Christopher C.

2014-01-01

Objectives Methohexital, a barbiturate anesthetic commonly used for electroconvulsive therapy (ECT), possesses dose-dependent anticonvulsant properties, and its use can interfere with effective seizure therapy in patients with high seizure thresholds. Ketamine, a NMDA-antagonist with epileptogenic properties not broadly used for ECT inductions, is a commonly used induction agent for general anesthesia. Recent studies suggest that the use of ketamine is effective in allowing successful ECT treatment in patients with high seizure thresholds without an increase in side-effects. In this preliminary study, we directly compared the recovery and re-orientation times of subjects receiving ketamine and methohexital for ECTs. Methods Twenty patients were randomized in a cross-over design to receive methohexital and ketamine for ECT inductions in alternating fashion for six trials. Primary outcome measures were recovery time (voluntary movement, respiratory effort, blood pressure, consciousness, and O2 saturation) and re-orientation time. Secondary outcome measures were individual recovery variables, side-effect occurrence, and seizure duration. Results: Overall recovery time was not significantly different between the two treatment arms (F(1,17) = 0.72, P = 0.41). Re-orientation time was faster in the methohexital arm (F(1,17) = 9.23, P = 0.007). Conclusion Ketamine inductions resulted in higher number of side-effects, higher subject dropout rates, and a longer reorientation time with respect to methohexital inductions. No significant difference in post-anesthesia recovery time was found between the ketamine and methohexital arms. Intolerability to ketamine affected a significant proportion of subjects, and suggests that ketamine should remain as an alternative or adjunctive agent for patients with high seizure thresholds. PMID:24755722

Differential interaction with the serotonin system by S-ketamine, vortioxetine, and fluoxetine in a genetic rat model of depression.

PubMed

du Jardin, Kristian Gaarn; Liebenberg, Nico; Müller, Heidi Kaastrup; Elfving, Betina; Sanchez, Connie; Wegener, Gregers

2016-07-01

The mechanisms mediating ketamine's antidepressant effect have only been partly resolved. Recent preclinical reports implicate serotonin (5-hydroxytryptamine; 5-HT) in the antidepressant-like action of ketamine. Vortioxetine is a multimodal-acting antidepressant that is hypothesized to exert its therapeutic activity through 5-HT reuptake inhibition and modulation of several 5-HT receptors. The objective of this study was to evaluate the therapeutic-like profiles of S-ketamine, vortioxetine, and the serotonin reuptake inhibitor fluoxetine in response to manipulation of 5-HT tone. Flinders Sensitive Line (FSL) rats, a genetic model of depression, were depleted of 5-HT by repeated administration of 4-chloro-DL-phenylalanine methyl ester HCl (pCPA). Using pCPA-pretreated and control FSL rats, we investigated the acute and sustained effects of S-ketamine (15 mg/kg), fluoxetine (10 mg/kg), or vortioxetine (10 mg/kg) on recognition memory and depression-like behavior in the object recognition task (ORT) and forced swim test (FST), respectively. The behavioral phenotype of FSL rats was unaffected by 5-HT depletion. Vortioxetine, but not fluoxetine or S-ketamine, acutely ameliorated the memory deficits of FSL rats in the ORT irrespective of 5-HT tone. No sustained effects were observed in the ORT. In the FST, all three drugs demonstrated acute antidepressant-like activity but only S-ketamine had sustained effects. Unlike vortioxetine, the antidepressant-like responses of fluoxetine and S-ketamine were abolished by 5-HT depletion. These observations suggest that the acute and sustained antidepressant-like effects of S-ketamine depend on endogenous stimulation of 5-HT receptors. In contrast, the acute therapeutic-like effects of vortioxetine on memory and depression-like behavior may be mediated by direct activity at 5-HT receptors.

Low-Dose Ketamine Infusion for Adjunct Management during Vaso-occlusive Episodes in Adults with Sickle Cell Disease: A Case Series.

PubMed

Palm, Nicole; Floroff, Catherine; Hassig, Tanna B; Boylan, Alice; Kanter, Julie

2018-05-23

The optimal management of recurrent painful episodes in individuals living with sickle cell disease (SCD) remains unclear. Currently, the primary treatment for these episodes remains supportive, using fluids and intravenous opioid and anti-inflammatory medications. Few reports have described the use of adjunct subanesthetic doses of ketamine to opioids for treatment of refractory pain in SCD. This article reports a retrospective case series of five patients admitted to the intensive care unit (ICU) with prolonged vaso-occlusive episodes (VOEs). Patients were treated with a continuous-infusion of low-dose ketamine (up to 5 µg/kg/min) after insufficient pain control with opioid analgesic therapy. Outcomes studied included impact on opioid analgesic use, a description of ketamine dosing strategy, and an analysis of adverse events due to opioid or ketamine analgesia. Descriptive statistics are provided. During ketamine infusion, patients experienced a lower reported pain score (mean numeric rating scale [NRS] score 7.2 vs. 6.4), reduced opioid-induced adverse effects, and decreased opioid dosing requirements (median reduction of 90 mg morphine equivalents per patient). The average duration of severe pain during admission prior to ketamine therapy was 8 days. Only one of five patients reported an adverse effect (vivid dreams) secondary to ketamine infusion. The Richmond Agitation Sedation Scale (RASS) was assessed throughout therapy, with only one patient experiencing light drowsiness. Low-dose ketamine infusion may be considered as an adjunct analgesic agent in patients with vaso-occlusive episodes who report continued severe pain despite high-dose opioid therapy, particularly those experiencing opioid-induced adverse effects.

Restoring mood balance in depression: ketamine reverses deficit in dopamine-dependent synaptic plasticity.

PubMed

Belujon, Pauline; Grace, Anthony A

2014-12-15

One of the most novel and exciting findings in major depressive disorder research over the last decade is the discovery of the fast-acting and long-lasting antidepressant effects of ketamine. Indeed, the therapeutic effects of classic antidepressants, such as selective serotonin reuptake inhibitors, require a month or longer to be expressed, with about a third of major depressive disorder patients resistant to treatment. Clinical studies have shown that a low dose of ketamine exhibits fast-acting relatively sustained antidepressant action, even in treatment-resistant patients. However, the mechanisms of ketamine action at a systems level remain unclear. Wistar-Kyoto rats were exposed to inescapable, uncontrollable footshocks. To evaluate learned helplessness behavior, we used an active avoidance task in a shuttle box equipped with an electrical grid floor. After helplessness assessment, we performed in vivo electrophysiological recordings first from ventral tegmental area dopaminergic (DA) neurons and second from accumbens neurons responsive to fimbria stimulation. Ketamine was injected and tested on helpless behavior and electrophysiological recordings. We show that ketamine is able to restore the integrity of a network by acting on the DA system and restoring synaptic dysfunction observed in stress-induced depression. We show that part of the antidepressant effect of ketamine is via the DA system. Indeed, injection of ketamine restores a decreased dopamine neuron population activity, as well as synaptic plasticity (long-term potentiation) in the hippocampus-accumbens pathway, via, in part, activation of D1 receptors. This work provides a unique systems perspective on the mechanisms of ketamine on a disrupted limbic system. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

GLYX-13, a NMDA Receptor Glycine-Site Functional Partial Agonist, Induces Antidepressant-Like Effects Without Ketamine-Like Side Effects

PubMed Central

Burgdorf, Jeffrey; Zhang, Xiao-lei; Nicholson, Katherine L; Balster, Robert L; David Leander, J; Stanton, Patric K; Gross, Amanda L; Kroes, Roger A; Moskal, Joseph R

2013-01-01

Recent human clinical studies with the NMDA receptor (NMDAR) antagonist ketamine have revealed profound and long-lasting antidepressant effects with rapid onset in several clinical trials, but antidepressant effects were preceded by dissociative side effects. Here we show that GLYX-13, a novel NMDAR glycine-site functional partial agonist, produces an antidepressant-like effect in the Porsolt, novelty induced hypophagia, and learned helplessness tests in rats without exhibiting substance abuse-related, gating, and sedative side effects of ketamine in the drug discrimination, conditioned place preference, pre-pulse inhibition and open-field tests. Like ketamine, the GLYX-13-induced antidepressant-like effects required AMPA/kainate receptor activation, as evidenced by the ability of NBQX to abolish the antidepressant-like effect. Both GLYX-13 and ketamine persistently (24 h) enhanced the induction of long-term potentiation of synaptic transmission and the magnitude of NMDAR-NR2B conductance at rat Schaffer collateral-CA1 synapses in vitro. Cell surface biotinylation studies showed that both GLYX-13 and ketamine led to increases in both NR2B and GluR1 protein levels, as measured by Western analysis, whereas no changes were seen in mRNA expression (microarray and qRT-PCR). GLYX-13, unlike ketamine, produced its antidepressant-like effect when injected directly into the medial prefrontal cortex (MPFC). These results suggest that GLYX-13 produces an antidepressant-like effect without the side effects seen with ketamine at least in part by directly modulating NR2B-containing NMDARs in the MPFC. Furthermore, the enhancement of ‘metaplasticity' by both GLYX-13 and ketamine may help explain the long-lasting antidepressant effects of these NMDAR modulators. GLYX-13 is currently in a Phase II clinical development program for treatment-resistant depression. PMID:23303054

mTOR activation is required for the anti-alcohol effect of ketamine, but not memantine, in alcohol-preferring rats

PubMed Central

Sabino, Valentina; Narayan, Aditi R.; Zeric, Tamara; Steardo, Luca; Cottone, Pietro

2013-01-01

Glutamate NMDA receptors mediate many molecular and behavioral effects of alcohol, and they play a key role in the development of excessive drinking. Uncompetitive NMDA receptor antagonists may, therefore, have therapeutic potential for alcoholism. The first aim was to compare the effects of the NMDA antagonists memantine and ketamine on ethanol and saccharin drinking in alcohol-preferring rats. The second aim was to determine whether the effects of the two NMDA receptor antagonists were mediated by the mammalian target of rapamycin (mTOR). TSRI Sardinian alcohol-preferring rats were allowed to self-administer either 10% w/v ethanol or 0.08% w/v saccharin, and water. Operant responding and motor activity were assessed following administration of either memantine (0–10 mg/kg) or ketamine (0–20 mg/kg). Finally, ethanol self-administration was assessed in rats administered with either memantine or ketamine but pretreated with the mTOR inhibitor rapamycin (2.5 mg/kg). The uncompetitive NMDA receptor antagonists memantine and ketamine dose-dependently reduced ethanol drinking in alcohol-preferring rats; while memantine had a preferential effect on alcohol over saccharin, ketamine reduced responding for both solutions. Neither antagonist induced malaise, as shown by the lack of effect on water intake and motor activity. The mTOR inhibitor rapamycin blocked the effects of ketamine, but not those of memantine. Memantine and ketamine both reduce alcohol drinking in alcohol-preferring rats, but only memantine is selective for alcohol. The effects of ketamine, but not memantine, are mediated by mTOR. The results support the therapeutic potential of uncompetitive NMDA receptor antagonists, especially memantine, in alcohol addiction. PMID:23466691

Nefopam and Ketamine Comparably Enhance Postoperative Analgesia

PubMed Central

Kapfer, Barbara; Alfonsi, Pascal; Guignard, Bruno; Sessler, Daniel I.; Chauvin, Marcel

2005-01-01

Summary Opioids alone sometimes provide insufficient postoperative analgesia. Co-administration of drugs may reduce opioid use and to improve opioid efficacy. We therefore tested the hypothesis that administration of ketamine or nefopam, to postoperative patients with pain only partly alleviated by morphine, limits the amount of subsequent opioid necessary to produce adequate analgesia. Patients (n=77) recovering from major surgery were given up to 9 mg intravenous morphine. Those still suffering from pain were randomly assigned to blinded administration of: 1) isotonic saline (Control, n=21); 2) ketamine 10 mg (Ketamine, n=22); or, 3) nefopam 20 mg (Nefopam, n=22). Three-mg morphine boluses were subsequently given at 5-minute intervals until adequate analgesia was obtained, or 60 minutes elapsed after the beginning of the study drug administration, or ventilation became insufficient (respiratory rate < 10 breath/minute or saturation by pulse oxymetery < 95%). Supplemental morphine (i.e., after test drug administration) requirements were significantly greater in the Control group [17 ± 10 (SD) mg] than in the Nefopam (10 ± 5 mg, P < 0.005) or Ketamine (9 ± 5 mg, P < 0.001) groups. Morphine titration was successful in all Ketamine and Nefopam patients, but failed in four Control patients (two from respiratory toxicity and two from persistent pain). Tachycardia and profuse sweating were more frequent in patients given nefopam and sedation was greater with ketamine; however, the incidence of other potential complications did not differ between groups. Implications We conclude that ketamine 10 mg and nefopam 20 mg comparably potentiate opioid analgesia, each reducing opioid need by approximately 40%. Ketamine administration was associated with sedation whereas nefopam produced tachycardia and sweating. However, none of the side effects was serious. Either drug can thus be used to potentiate opioid analgesia. PMID:15616073

Validation of an enzyme-linked immunosorbent assay screening method and a liquid chromatography-tandem mass spectrometry confirmation method for the identification and quantification of ketamine and norketamine in urine samples from Malaysia.

PubMed

Harun, Norlida; Anderson, Robert A; Miller, Eleanor I

2009-01-01

An ELISA and a liquid chromatography-tandem mass spectrometry (LC-MS-MS) confirmation method were developed and validated for the identification and quantitation of ketamine and its major metabolite norketamine in urine samples. The Neogen ketamine microplate ELISA was optimized with respect to sample and enzyme conjugate volumes and the sample preincubation time before addition of the enzyme conjugate. The ELISA kit was validated to include an assessment of the dose-response curve, intra- and interday precision, limit of detection (LOD), and cross-reactivity. The sensitivity and specificity were calculated by comparison to the results from the validated LC-MS-MS confirmation method. An LC-MS-MS method was developed and validated with respect to LOD, lower limit of quantitation (LLOQ), linearity, recovery, intra- and interday precision, and matrix effects. The ELISA dose-response curve was a typical S-shaped binding curve, with a linear portion of the graph observed between 25 and 500 ng/mL for ketamine. The cross-reactivity of 200 ng/mL norketamine to ketamine was 2.1%, and no cross-reactivity was detected with 13 common drugs tested at 10,000 ng/mL. The ELISA LOD was calculated to be 5 ng/mL. Both intra- (n = 10) and interday (n = 50) precisions were below 5.0% at 25 ng/mL. The LOD for ketamine and norketamine was calculated statistically to be 0.6 ng/mL. The LLOQ values were also calculated statistically and were 1.9 ng/mL and 2.1 ng/mL for ketamine and norketamine, respectively. The test linearity was 0-1200 ng/mL with correlation coefficient (R(2)) > 0.99 for both analytes. Recoveries at 50, 500, and 1000 ng/mL range from 97.9% to 113.3%. Intra- (n = 5) and interday (n = 25) precisions between extracts for ketamine and norketamine were excellent (< 10%). Matrix effects analysis showed an average ion suppression of 5.7% for ketamine and an average ion enhancement of 13.0% for norketamine for urine samples collected from six individuals. A comparison of ELISA and LC-MS-MS results demonstrated a sensitivity, specificity, and efficiency of 100%. These results indicated that a cutoff value of 25 ng/mL ketamine in the ELISA screen is particularly suitable and reliable for urine testing in a forensic toxicology setting. Furthermore, both ketamine and norketamine were detected in all 34 urine samples collected from individuals socializing in pubs by the Royal Malaysian Police. Ketamine concentrations detected by LC-MS-MS ranged from 22 to 31,670 ng/mL, and norketamine concentrations ranged from 25 to 10,990 ng/mL. The concentrations of ketamine and norketamine detected in the samples are most ikely indicative of ketamine abuse.

Improvement of arterial oxygenation in free-ranging moose (Alces alces) immobilized with etorphine-acepromazine-xylazine.

PubMed

Lian, Marianne; Evans, Alina L; Bertelsen, Mads F; Fahlman, Åsa; Haga, Henning A; Ericsson, Göran; Arnemo, Jon M

2014-08-15

The effect of intranasal oxygen and/or early reversal of xylazine with atipamezole on arterial oxygenation in free-ranging moose (Alces alces) immobilized with etorphine-acepromazine-xylazine with a cross-sectional clinical study on 33 adult moose was evaluated. Before treatment the mean±SD (range) partial pressure of arterial oxygen (PaO2) was 62±17 (26-99) mmHg. Twenty-six animals had a PaO2<80 mmHg. Ten had a PaO2 of 40-60 mmHg and three animals had a PaO2<40 mmHg. Intranasal oxygen and intravenous administration of atipamezole significantly increased the mean PaO2, as did the combination of the two. In contrast, atipamezole administered intramuscularly at the evaluated dose had no significant effect on arterial oxygenation. This study shows that intranasal oxygen effectively improved arterial oxygenation in immobilized moose, and that early intravenous reversal of the sedative component, in this case xylazine, in an opioid-based immobilization drug-protocol significantly improves arterial oxygenation.

Adjuvant effect of melatonin on anesthesia induced by thiopental sodium, ketamine, and ether in rats.

PubMed

Budhiraja, S; Singh, J

2005-12-01

This study evaluated the anesthetic effects of thiopental sodium, ketamine, and ether with concurrent administration of melatonin. The loss of righting reflex was taken to assess the onset of anesthesia. Melatonin (20 mg/kg, p.o.) potentiated the anesthetic effects of thiopental sodium (20 mg/kg, i.v.) and ketamine (50 mg/kg, i.p.). Melatonin pretreatment caused rapid onset of anesthesia after ketamine and thiopental sodium administration while the duration of action of these agents was prolonged. Melatonin failed to alter anesthetic effects of ether (2 mg/kg by open method) in rats. This study suggests that melatonin modulate mechanisms involved in induction of thiopental sodium and ketamine anesthesia. Copyright 2005 Prous Science. All rights reserved.

Effects of a single bilateral infusion of R-ketamine in the rat brain regions of a learned helplessness model of depression.

PubMed

Shirayama, Yukihiko; Hashimoto, Kenji

2017-03-01

Effects of a single bilateral infusion of R-enantiomer of ketamine in rat brain regions of learned helplessness model of depression were examined. A single bilateral infusion of R-ketamine into infralimbic (IL) portion of medial prefrontal cortex (mPFC), CA3 and dentate gyrus (DG) of the hippocampus showed antidepressant effects. By contrast, a single bilateral infusion of R-ketamine into prelimbic (PL) portion of mPFC, shell and core of nucleus accumbens, basolateral amygdala and central nucleus of the amygdala had no effect. This study suggests that IL of mPFC, CA3 and DG of hippocampus might be involved in the antidepressant actions of R-ketamine.

Ketamine for pain

PubMed Central

Jonkman, Kelly; Dahan, Albert; van de Donk, Tine; Aarts, Leon; Niesters, Marieke; van Velzen, Monique

2017-01-01

The efficacy of the N-methyl-D-aspartate receptor antagonist ketamine as an analgesic agent is still under debate, especially for indications such as chronic pain. To understand the efficacy of ketamine for relief of pain, we performed a literature search for relevant narrative and systematic reviews and meta-analyses. We retrieved 189 unique articles, of which 29 were deemed appropriate for use in this review. Ketamine treatment is most effective for relief of postoperative pain, causing reduced opioid consumption. In contrast, for most other indications (that is, acute pain in the emergency department, prevention of persistent postoperative pain, cancer pain, and chronic non-cancer pain), the efficacy of ketamine is limited. Ketamine’s lack of analgesic effect was associated with an increase in side effects, including schizotypical effects. PMID:28979762

21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ketamine hydrochloride injectable dosage forms. 522.1222 Section 522.1222 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms. ...

21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ketamine hydrochloride injectable dosage forms. 522.1222 Section 522.1222 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms. ...

21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ketamine hydrochloride injectable dosage forms. 522.1222 Section 522.1222 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms. ...

21 CFR 522.1222 - Ketamine hydrochloride injectable dosage forms.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ketamine hydrochloride injectable dosage forms. 522.1222 Section 522.1222 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... ANIMAL DRUGS § 522.1222 Ketamine hydrochloride injectable dosage forms. ...

International online survey to assess current practice in equine anaesthesia.

PubMed

Wohlfender, F D; Doherr, M G; Driessen, B; Hartnack, S; Johnston, G M; Bettschart-Wolfensberger, R

2015-01-01

Multicentre Confidential Enquiries into Perioperative Equine Fatalities (CEPEF) have not been conducted since the initial CEPEF Phases 1-3, 20 years ago. To collect data on current practice in equine anaesthesia and to recruit participants for CEPEF-4. Online questionnaire survey. An online questionnaire was prepared and the link distributed internationally to veterinarians possibly performing equine anaesthesia, using emails, posters, flyers and an editorial. The questionnaire included 52 closed, semiclosed and open questions divided into 8 subgroups: demographic data, anaesthetist, anaesthesia management (preoperative, technical equipment, monitoring, drugs, recovery), areas of improvements and risks and motivation for participation in CEPEF-4. Descriptive statistics and Chi-squared tests for comparison of categorical variables were performed. A total of 199 questionnaires were completed by veterinarians from 14 different countries. Of the respondents, 43% worked in private hospitals, 36% in private practices and 21% in university teaching hospitals. In 40 institutions (23%) there was at least one diplomate of the European or American colleges of veterinary anaesthesia and analgesia on staff. Individual respondents reported routinely employ the following anaesthesia monitoring modalities: electrocardiography (80%), invasive arterial blood pressures (70%), pulse oximetry (60%), capnography (55%), arterial blood gases (47%), composition of inspired and expired gases (45%) and body temperature (35%). Drugs administered frequently or routinely as part of a standard protocol were: acepromazine (44%), xylazine (68%), butorphanol (59%), ketamine (96%), diazepam (83%), isoflurane (76%), dobutamine (46%), and, as a nonsteroidal anti-inflammatory drug, phenylbutazone (73%) or flunixin meglumine (66%). Recovery was routinely assisted by 40%. The main factors perceived by the respondents to affect outcome of equine anaesthesia were the preoperative health status of the animal and training of the anaesthetist. Current practice in equine anaesthesia varies widely, and the study has highlighted important topics relevant for designing a future prospective multicentre cohort study (CEPEF-4). The Summary is available in Chinese - see Supporting information. © 2014 EVJ Ltd.

Paliperidone for the treatment of ketamine-induced psychosis: a case report.

PubMed

Zuccoli, M L; Muscella, A; Fucile, C; Carrozzino, R; Mattioli, F; Martelli, A; Orengo, S

2014-01-01

Ketamine is an anaesthetic and analgesic drug synthesized in the 1960s from phencyclidine. The recreational use of ketamine increased among the dance culture of techno and house music, in particular in clubs, discotheques, and rave parties. The psychotropic effects of ketamine are now well known and they range from dissociation to positive, negative, and cognitive schizophrenia-like symptoms. We report a case of a chronic oral consumption of ketamine which induced agitation, behavioral abnormalities, and loss of contact with reality in a poly-drug abuser; these symptoms persisted more than two weeks after the drug consumption had stopped. Antipsychotic treatment with paliperidone led to a successful management of the psychosis, getting a complete resolution of the clinical picture. Paliperidone has proven to be very effective in the treatment of ketamine-induced disorders. Moreover, the pharmacological action and metabolism of paliperidone are poorly dependent from the activity of liver enzymes, so that it seems to be one of the best second generation antipsychotics for the treatment of smokers and alcohol abusers.

Antidepressant effects of ketamine and the roles of AMPA glutamate receptors and other mechanisms beyond NMDA receptor antagonism.

PubMed

Aleksandrova, Lily R; Phillips, Anthony G; Wang, Yu Tian

2017-06-01

The molecular mechanisms underlying major depressive disorder remain poorly understood, and current antidepressant treatments have many shortcomings. The recent discovery that a single intravenous infusion of ketamine at a subanesthetic dose had robust, rapid and sustained antidepressant effects in individuals with treatment-resistant depression inspired tremendous interest in investigating the molecular mechanisms mediating ketamine's clinical efficacy as well as increased efforts to identify new targets for antidepressant action. We review the clinical utility of ketamine and recent insights into its mechanism of action as an antidepressant, including the roles of N -methyl-D-aspartate receptor inhibition, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor upregulation, activation of downstream synaptogenic signalling pathways and the production of an active ketamine metabolite, hydroxynorketamine. Emerging knowledge of the molecular mechanisms underlying both ketamine's positive therapeutic and detrimental side effects will aid the development of a new generation of much-needed superior antidepressant agents.

Ketamine-Based Anesthetic Protocols and Evoked Potential Monitoring: A Risk/Benefit Overview.

PubMed

Stoicea, Nicoleta; Versteeg, Gregory; Florescu, Diana; Joseph, Nicholas; Fiorda-Diaz, Juan; Navarrete, Víctor; Bergese, Sergio D

2016-01-01

Since its discovery, ketamine, a non-competitive N-methyl D-aspartate (NMDA) receptor antagonist related to phencyclidine, has been linked to multiple adverse reactions sometimes described as "out of body" and "near death experiences," including emergence phenomena, delusions, hallucinations, delirium, and confusion. Due to these effects, ketamine has been withdrawn from mainstream anesthetic use in adult patients. Evoked potentials (EPs) are utilized to monitor neural pathways during surgery, detect intraoperative stress or damage, detect and define the level of neural lesions, and define abnormalities. Unfortunately, many of the volatile anesthetics commonly used during spinal and neurologic procedures suppress EP amplitude and monitoring. Ketamine has been found in several preclinical and clinical studies to actually increase EP amplitude and thus has been used as an analgesic adjunct in procedures where EP monitoring is critical. Once the gap in our knowledge of ketamine's risks has been sufficiently addressed in animal models, informed clinical trials should be conducted in order to properly incorporate ketamine-based anesthetic regimens during EP-monitored neurosurgeries.

Patterns of Polydrug Use Among Ketamine Injectors in New York City

PubMed Central

LANKENAU, STEPHEN E.; CLATTS, MICHAEL C.

2007-01-01

Polydrug use is an important public health issue since it has been linked to significant adverse health outcomes. Recently, club drugs, including ketamine and other drugs used in dance/rave scenes, have been identified as key substances in new types of polydrug using patterns. While seemingly a self-explanatory concept, “polydrug” use constitutes multiple drug using practices that may impact upon health risks. Ketamine, a club drug commonly administered intranasally among youth for its disassociative properties, has emerged as a drug increasingly prevalent among a new hidden population of injection drug users (IDUs). Using an ethno-epidemiological methodology, we interviewed 40 young (<25 years old) ketamine injectors in New York during 2000–2002 to describe the potential health risks associated with ketamine and polydrug use. Findings indicate that ketamine was typically injected or sniffed in the context of a polydrug using event. Marijuana, alcohol, PCP, and speed were among the most commonly used drugs during recent ketamine using events. Polydrug using events were often quite variable regarding the sequencing of drug use, the drug combinations consumed, the forms of the drug utilized, and the modes of administrating the drug combinations. Future research should be directed towards developing a more comprehensive description of the risks associated with combining ketamine with other drugs, such as drug overdoses, the transmission of bloodborne pathogens, such as HIV and HCV, the short- and long-term effects of drug combinations on cognitive functioning, and other unanticipated consequences associated with polydrug use. PMID:16048823

Behavioral and biochemical effects of ketamine and dextromethorphan relative to its antidepressant-like effects in Swiss Webster mice.

PubMed

Nguyen, Linda; Lucke-Wold, Brandon P; Logsdon, Aric F; Scandinaro, Anna L; Huber, Jason D; Matsumoto, Rae R

2016-09-28

Ketamine has been shown to produce rapid and robust antidepressant effects in depressed individuals; however, its abuse potential and adverse psychotomimetic effects limit its widespread use. Dextromethorphan (DM) may serve as a safer alternative on the basis of pharmacodynamic similarities to ketamine. In this proof-of-concept study, behavioral and biochemical analyses were carried out to evaluate the potential involvement of brain-derived neurotrophic factor (BDNF) in the antidepressant-like effects of DM in mice, with comparisons to ketamine and imipramine. Male Swiss, Webster mice were injected with DM, ketamine, or imipramine and their behaviors were evaluated in the forced-swim test and the open-field test. Western blots were used to measure BDNF and its precursor, pro-BDNF, protein expression in the hippocampus and the frontal cortex of these mice. Our results show that both DM and imipramine reduced immobility time in the forced-swim test without affecting locomotor activity, whereas ketamine reduced immobility time and increased locomotor activity. Ketamine also rapidly (within 40 min) increased pro-BDNF expression in an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor-dependent manner in the hippocampus, whereas DM and imipramine did not alter pro-BDNF or BDNF levels in either the hippocampus or the frontal cortex within this timeframe. These data show that DM shares some features with both ketamine and imipramine. Additional studies examining DM may aid in the development of more rapid, safe, and efficacious antidepressant treatments.

The effects of subarachnoid administration of preservative-free S(+)-ketamine on spinal cord and meninges in dogs.

PubMed

Rojas, Alfredo Cury; Alves, Juliana Gaiotto; Moreira E Lima, Rodrigo; Esther Alencar Marques, Mariângela; Moreira de Barros, Guilherme Antônio; Fukushima, Fernanda Bono; Modolo, Norma Sueli Pinheiro; Ganem, Eliana Marisa

2012-02-01

The N-methyl-d-aspartate receptor antagonist ketamine and its active enantiomer, S(+)-ketamine, have been injected in the epidural and subarachnoid spaces to treat acute postoperative pain and relieve neuropathic pain syndrome. In this study we evaluated the effects of a single dose of preservative-free S(+)-ketamine, in doses usually used in clinical practice, in the spinal cord and meninges of dogs. Under anesthesia (IV etomidate (2 mg/kg) and fentanyl (0.005 mg/kg), 16 dogs (6 to 15 kg) were randomized to receive a lumbar intrathecal injection (L5/6) of saline solution of 0.9% (control group) or S(+)-ketamine 1 mg/kg(-1) (ketamine group). All doses were administered in a volume of 1 mL over a 10-second interval. Accordingly, injection solution ranged from 0.6% to 1.5%. After 21 days of clinical observation, the animals were killed; spinal cord, cauda equina root, and meninges were removed for histological examination with light microscopy. Tissues were examined for demyelination (Masson trichrome), neuronal death (hematoxylin and eosin) and astrocyte activation (glial fibrillary acidic protein). No clinical or histological alterations of spinal tissue or meninges were found in animals from either control or ketamine groups. A single intrathecal injection of preservative-free S(+)-ketamine, at 1 mg/kg(-1) dosage, over a concentration range of 6 to 15 mg/mL injected in the subarachnoid space in a single puncture, did not produce histological alterations in this experimental model.

Ketamine reduces the need for intubation in patients with acute severe mental illness and agitation requiring transport to definitive care: An observational study.

PubMed

Parsch, Cathrin S; Boonstra, Adrianne; Teubner, David; Emmerton, Wade; McKenny, Brian; Ellis, Daniel Y

2017-06-01

The aim of this study was to review mental health patients transported by a dedicated statewide critical care retrieval team before and after the implementation of a ketamine sedation guideline. This is a a retrospective cohort study of mental health patients with acute behavioural disturbance, transported between January 2010 and December 2015. A total of 78 patients were transported in the study period, 50 before and 28 after implementation of the ketamine guideline in June 2013. The introduction of the ketamine guideline was associated with a significant reduction in intubation for transport (36.00 vs 7.14%) (odds ratio 0.14, 95% confidence interval 0.02-0.71, P < 0.01). The likelihood of utilising ketamine for non-intubated patients (n = 58) was higher in the period after implementation (37.50 vs 84.62%, odds ratio 9.17, 95% confidence interval 2.54-33.08, P < 0.005). The incidence of complications in our series was low. The implementation of a ketamine clinical practice guideline for agitated mental health patients was associated with an increase in the number of patients receiving ketamine as part of their sedation regime and a reduction in the number of patients requiring intubation for transport. Appropriately trained critical care retrieval teams should consider ketamine as part of the sedation regime for agitated mental health patients. © 2017 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Ketamine as an adjuvant to opioids for cancer pain.

PubMed

Bell, Rae F; Eccleston, Christopher; Kalso, Eija A

2017-06-28

This is an update of a review first published in 2003 and updated in 2012.Ketamine is a commonly used anaesthetic agent, and in subanaesthetic doses is also given as an adjuvant to opioids for the treatment of refractory cancer pain, when opioids alone or in combination with appropriate adjuvant analgesics prove to be ineffective. Ketamine is known to have psychomimetic (including hallucinogenic), urological, and hepatic adverse effects. To determine the effectiveness and adverse effects of ketamine as an adjuvant to opioids for refractory cancer pain in adults. For this update, we searched MEDLINE (OVID) to December 2016. We searched CENTRAL (CRSO), Embase (OVID) and two clinical trial registries to January 2017. The intervention considered by this review was the addition of ketamine, given by any route of administration, in any dose, to pre-existing opioid treatment given by any route and in any dose, compared with placebo or active control. We included studies with a group size of at least 10 participants who completed the trial. Two review authors independently assessed the search results and performed 'Risk of bias' assessments. We aimed to extract data on patient-reported pain intensity, total opioid consumption over the study period; use of rescue medication; adverse events; measures of patient satisfaction/preference; function; and distress. We also assessed participant withdrawal (dropout) from trial. We assessed the quality of the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation). One new study (185 participants) was identified by the updated search and included in the review. We included a total of three studies in this update.Two small studies, both with cross-over design, with 20 and 10 participants respectively, were eligible for inclusion in the original review. One study with 20 participants examined the addition of intrathecal ketamine to intrathecal morphine, compared with intrathecal morphine alone. The second study with 10 participants examined the addition of intravenous ketamine bolus in two different doses to ongoing morphine therapy, compared with placebo. Both of these studies reported reduction in pain intensity and reduction in morphine requirements when ketamine was added to opioid for refractory cancer pain. The new study identified by the updated search had a parallel group design and 185 participants. This placebo-controlled study examined rapid titration of subcutaneous ketamine to high dose (500 mg) in participants who were using different opioids. There were no differences between groups for patient-reported pain intensity.Pooling of the data from the three included trials was not appropriate because of clinical heterogeneity.The study examining intrathecal drug administration reported no adverse events related to ketamine. In the study using intravenous bolus administration, ketamine caused hallucinations in four of 10 participants. In the rapid dose escalation/high-dose subcutaneous ketamine study, there was almost twice the incidence of adverse events in the ketamine group, compared to the placebo group, with the most common adverse events being needle site irritation and cognitive disturbance. Two serious adverse events (bradyarrhythmia and cardiac arrest) thought to be related to ketamine were also reported in this trial.For all three studies there was an unclear risk of bias overall. Using GRADE, we judged the quality of the evidence to be very low due to study limitations and imprecision due to the small number of participants in all comparisons. Current evidence is insufficient to assess the benefits and harms of ketamine as an adjuvant to opioids for the relief of refractory cancer pain. The evidence was of very low quality, meaning that it does not provide a reliable indication of the likely effect, and the likelihood that the effect will be substantially different is high. Rapid dose escalation of ketamine to high dose (500 mg) does not appear to have clinical benefit and may be associated with serious adverse events. More randomised controlled trials (RCTs) examining specific low-dose ketamine clinical regimens in current use are needed.

Perioperative Ketamine Administration for Thoracotomy Pain.

PubMed

Moyse, Daniel W; Kaye, Alan D; Diaz, James H; Qadri, Muhammad Y; Lindsay, David; Pyati, Srinivas

2017-03-01

Of all the postsurgical pain conditions, thoracotomy pain poses a particular therapeutic challenge in terms of its prevalence, severity, and ensuing postoperative morbidity. Multiple pain generators contribute to the severity of post-thoracotomy pain, and therefore a multimodal analgesic therapy is considered to be a necessary strategy. Along with opioids, thoracic epidural analgesia, and paravertebral blocks, N-Methyl-D-Aspartate (NMDA) receptor antagonists such as ketamine have been used as adjuvants to improve analgesia. We reviewed the evidence for the efficacy of intravenous and epidural administration of ketamine in acute post-thoracotomy pain management, and its effectiveness in reducing chronic post-thoracotomy pain. Systematic literature review and an analytic study of a data subset were performed. We searched PubMed, Embase, and Cochrane reviews using the key terms "ketamine," "neuropathic pain," "postoperative," and "post-thoracotomy pain syndrome." The search was limited to human trials and included all studies published before January 2015. Data from animal studies, abstracts, and letters were excluded. All studies not available in the English language were excluded. The manuscript bibliographies were reviewed for additional related articles. We included randomized controlled trials and retrospective studies, while excluding individual case reports. This systematic literature search yielded 15 randomized control trials evaluating the efficacy of ketamine in the treatment of acute post-thoracotomy pain; fewer studies assessed its effect on attenuating chronic post-thoracotomy pain. The majority of reviewed studies demonstrated that ketamine has efficacy in reduction of acute pain, but the evidence is limited on the long-term benefits of ketamine to prevent post-thoracotomy pain syndrome, regardless of the route of administration. A nested analytical study found there is a statistically significant reduction in acute post-thoracotomy pain with IV or epidural ketamine. However currently, the evidence for a role of ketamine as a preventative agent for chronic post-thoracotomy pain is insufficient due to the heterogeneity of the studies reviewed with regard to the route of administration, dosage, and outcome measures. The evidence for a role of ketamine as a preventative agent for chronic post-thoracotomy pain is insufficient due to the heterogeneity of the studies reviewed. The majority of randomized controlled trials reviewed show no role for ketamine in attenuating or preventing post-thoracotomy pain syndrome at variable follow-up lengths. Therefore, additional research is warranted with consideration of risk factors and long-term follow-up for chronic post-thoracotomy pain though the evidence for benefit appears clear for acute post-thoracotomy pain.Key words: Ketamine, postoperative, thoracotomy pain, post thoracotomy pain syndrome, neuropathic pain.

The effects of xylazine, detomidine, acepromazine and butorphanol on equine solid phase gastric emptying rate.

PubMed

Sutton, D G M; Preston, T; Christley, R M; Cohen, N D; Love, S; Roussel, A J

2002-07-01

The aim of this study was to measure the effects of specific commonly used sedative protocols on equine solid phase gastric emptying rate, using the 13C-octanoic acid breath test (13C-OABT). The gastric emptying of a standard 13C-labelled test meal was measured once weekly in 8 mature horses over two 4 week treatment periods. Each horse acted as its own control. In treatment Period 1, saline (2 ml i.v.), xylazine (0.5 mg/kg i.v.), detomidine (0.01 mg/kg i.v.) or detomidine/butorphanol combination (0.01/0.02 mg/kg i.v.) was administered in randomised order after ingestion of the test meal. During treatment Period 2, test meal consumption was followed by saline, xylazine (1.0 mg/kg i.v.), or detomidine (0.03 mg/kg i.v.) administration, or preceded by acepromazine (0.05 mg/kg i.m.) in randomised order. The 13C:12C ratio of sequential expiratory breath samples was determined by isotope ratio mass spectrometry, and used to measure the gastric half-emptying time, t 1/2, and duration of the lag phase, t lag, for each of the 64 tests. In treatment Period 1, detomidine/butorphanol prolonged both t 1/2 and t lag with respect to xylazine 0.5 mg/kg and the saline control (P < 0.05). In Period 2, detomidine 0.03 mg/kg delayed each parameter with respect to saline, acepromazine and xylazine 1.0 mg/kg (P < 0.001). Xylazine 1.0 mg/kg also lengthened t lag relative to the saline control (P = 0.0004), but did not cause a significant change in t 1/2. Comparison of treatment periods showed that the inhibitory effect of detomidine on gastric emptying rate was dose related (P<0.05). These findings may have clinical significance for case selection when these agents are used for purposes of sedation and/or analgesia.

Pre-anesthetic meperidine: associated vomiting and gastroesophageal reflux during the subsequent anesthetic in dogs.

PubMed

Wilson, Deborah V; Tom Evans, A; Mauer, Whitney A

2007-01-01

To determine the effect of meperidine administered prior to anesthesia on the incidence of vomiting before, and gastroesophageal reflux (GER) and regurgitation during, the subsequent period of anesthesia in dogs. Randomized, controlled trial. A total of 60 healthy dogs, 4.3 +/- 2.3 years old, and weighing 35.5 +/- 13.1 kg. Dogs were admitted to the study if they were healthy, had no history of vomiting, and were scheduled to undergo elective orthopedic surgery. The anesthetic protocol used was standardized to include thiopental and isoflurane in oxygen. Dogs were randomly selected to receive one of the following pre-medications: morphine (0.66 mg kg(-1) IM) with acepromazine (0.044 mg kg(-1) IM), meperidine (8.8 mg kg(-1) IM) with acepromazine (0.044 mg kg(-1) IM) or meperidine alone (8.8 mg kg(-1) IM). A sensor-tipped catheter was placed to measure esophageal pH during anesthesia. Gastro-esophageal reflux was judged to have occurred if there was a decrease in esophageal pH below four or an increase above 7.5. No dogs vomited after the administration of meperidine, but 50% of dogs vomited after the administration of morphine. When compared with morphine, treatment with meperidine alone or combined with acepromazine before anesthesia was associated with a 55% and 27% reduction in absolute risk of developing GER, respectively. Dogs receiving meperidine alone were significantly less sedate than other dogs in the study, and required more thiopental to induce anesthesia. Arterial blood pressure and heart rate were not significantly different between groups at the start of the measurement period. Cutaneous erythema and swelling were evident in four dogs receiving meperidine. Administration of meperidine to healthy dogs prior to anesthesia was not associated with vomiting and tended to reduce the occurrence of GER, but produced less sedation when compared with morphine. Meperidine is not a useful addition to the anesthetic protocol if prevention of GER is desired.

Improvement of arterial oxygenation in free-ranging moose (Alces alces) immobilized with etorphine-acepromazine-xylazine

PubMed Central

2014-01-01

Background The effect of intranasal oxygen and/or early reversal of xylazine with atipamezole on arterial oxygenation in free-ranging moose (Alces alces) immobilized with etorphine-acepromazine-xylazine with a cross-sectional clinical study on 33 adult moose was evaluated. Moose were darted from a helicopter with 3.37 mg etorphine, 15 mg acepromazine and 75 mg xylazine. Intranasal oxygen at a flow rate of 4 L/min and/or early reversal of xylazine with 7.5 mg atipamezole to improve oxygenation was evaluated, using four treatment regimens; intranasal oxygen (n = 10), atipamezole intramuscularly (n = 6), atipamezole intravenously (n = 10), or a combination of atipamezole intravenously and intranasal oxygen (n = 7). Arterial blood was collected 7–30 minutes (min) after darting, and again 15 min after institution of treatment and immediately analyzed using an i-STAT®1 Portable Clinical Analyzer. Results Before treatment the mean ± SD (range) partial pressure of arterial oxygen (PaO2) was 62 ± 17 (26–99) mmHg. Twenty-six animals had a PaO2 < 80 mmHg. Ten had a PaO2 of 40–60 mmHg and three animals had a PaO2 < 40 mmHg. Intranasal oxygen and intravenous administration of atipamezole significantly increased the mean PaO2, as did the combination of the two. In contrast, atipamezole administered intramuscularly at the evaluated dose had no significant effect on arterial oxygenation. Conclusions This study shows that intranasal oxygen effectively improved arterial oxygenation in immobilized moose, and that early intravenous reversal of the sedative component, in this case xylazine, in an opioid-based immobilization drug-protocol significantly improves arterial oxygenation. PMID:25124367

Aura in some patients with familial hemiplegic migraine can be stopped by intranasal ketamine.

PubMed

Kaube, H; Herzog, J; Käufer, T; Dichgans, M; Diener, H C

2000-07-12

Migraine aura is probably caused by cortical-spreading depression. No treatment for acute and severe migraine aura has been described previously. The effect of ketamine (25 mg intranasally) was studied in 11 patients with severe, disabling auras resulting from familial hemiplegic migraine. In five patients ketamine reproducibly reduced the severity and duration of the neurologic deficits, whereas in the remaining six patients no beneficial effect was seen. Ketamine offers, for the first time, a possible treatment option for severe and prolonged aura.

Ketamine use in Taiwan: Moral panic, civilizing processes, and democratization.

PubMed

Hsu, Liang-Yin

2014-07-01

Ketamine use among young people in Taiwan has increased in recent years. Believing ketamine users to be a threat to social order and harsh punishment to be a deterrent, some legislators have called for upgrading ketamine use to a more serious criminal offence. These calls have been repeatedly rebuffed by the advisory council which sets drug policy, suggesting that the perceived problem does not correlate to the actual one. In this commentary, I argue that the calls of legislators constitute a 'moral panic,' and follow Rohloff (2011) in connecting the phenomenon to Elias' (2000) concept of civilizing and decivilizing processes. In addition, I demonstrate that moral panic - in the ketamine case at least - is shaped by the legacy of authoritarianism. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of ketamine dose on self-rated dissociation in patients with treatment refractory anxiety disorders.

PubMed

Castle, Cameron; Gray, Andrew; Neehoff, Shona; Glue, Paul

2017-10-01

Patients receiving ketamine for refractory depression and anxiety report dissociative symptoms in the first 60 min post-dose. The most commonly used instrument to assess this is the Clinician-Administered Dissociative States Scale (CADSS), developed based on the assessment of patients with dissociative symptoms. Its psychometric properties for ketamine-induced dissociation have not been reported. We evaluated these from a study using 0.25-1 mg/kg ketamine and midazolam (as an active control) in 18 patients with treatment-resistant anxiety. Dissociation ratings were increased by ketamine in a dose-dependent manner. In contrast, midazolam showed no effect on ratings of dissociation. For individual CADSS items, the magnitude of change and the ketamine dose at which changes were observed were not homogenous. The Cronbach alpha for the total scale was high (0.937), with acceptable item-rest correlations for almost all individual items. Purposefully removing items to maximise alpha did not lead to meaningful improvements. Acceptable internal consistency was still observed after removing items which lacked evidence of responsiveness at lower doses. The high Cronbach alpha values identified in this study suggests that the CADSS is an internally consistent instrument for evaluating ketamine-induced dissociation in clinical trials in anxiety, although it does not capture symptoms such as thought disorder.

[The Analgesic Sparing Effect of Ketamine for Postoperative Pain Management after Pediatric Surgery on the Body Surface].

PubMed

Urabe, Tomoaki; Nakanuno, Ryuichi; Hayase, Kazuma; Sasada, Shogo; Iwamitsu, Reimi; Senami, Masaki

2016-04-01

It is reported that ketamine, a N-methyl-D-aspertate (NMDA) receptor antagonist, can provide analgesic effect improving postoperative pain management and decrease the supplementary analgesic requirement. We investigated the analgesic sparing effect of ketamine for postoperative pain in children undergoing surgery of body surface. Fifty eight patients (0-9 yrs) who had surgery of body surface were divided into two groups (ketamine : n = 27, Group K or control : n = 31, Group N). Postoperative analgesia extracted from charts was retrospectively evaluated by the times patients used analgesics until discharge after the operations. Chi-square and Mann-Whitney U tests were used for statistical analysis. Results : The ketamine group received an intrave- nous bolus of ketamine (1 mg - kg-1) before surgical skin incision. However, there were no significant differ- ences of usage (Group K vs Group N : 4/27 vs 7/31, P=0.45) and frequency of supplementary analgesic us- ages (P=0.85) among groups. In addition, there were also no significant demographic differences between the two groups. Conclusions : Our investigation suggests that the intravenous bolus of ketamine (1 mg - kg-1) before surgical skin incision does not decrease the supple- mentary analgesic requirements on postoperative pain management in pediatric surgery of the body surface.

Caudal epidural analgesia using lidocaine alone or in combination with ketamine in dromedary camels Camelus dromedarius.

PubMed

Azari, Omid; Molaei, Mohammad M; Ehsani, Amir H

2014-02-27

This study was performed to investigate the analgesic effect of lidocaine and a combination of lidocaine and ketamine following epidural administration in dromedary camels. Ten 12-18-month-old camels were randomly divided into two equal groups. In group L, the animals received 2% lidocaine (0.22 mg/kg) and in group LK the animals received a mixture of 10% ketamine (1 mg/kg) and 2% lidocaine (0.22 mg/kg) administered into the first intercoccygeal (Co1-Co2) epidural space while standing. Onset time and duration of caudal analgesia, sedation level and ataxia were recorded after drug administration. Data were analysed by U Mann-Whitney tests and significance was taken as p < 0.05. The results showed that epidural lidocaine and co-administration of lidocaine and ketamine produced complete analgesia in the tail, anus and perineum. Epidural administration of the lidocaine-ketamine mixture resulted in mild to moderate sedation, whilst the animals that received epidural lidocaine alone were alert and nervous during the study. Ataxia was observed in all test subjects and was slightly more severe in camels that received the lidocaine-ketamine mixture. It was concluded that epidural administration of lidocaine plus ketamine resulted in longer caudal analgesia in standing conscious dromedary camels compared with the effect of administering lidocaine alone.

The interplay of cannabinoid and NMDA glutamate receptor systems in humans: preliminary evidence of interactive effects of cannabidiol and ketamine in healthy human subjects.

PubMed

Hallak, Jaime E C; Dursun, Serdar M; Bosi, Daniel C; de Macedo, Ligia Ribeiro Horta; Machado-de-Sousa, João Paulo; Abrão, João; Crippa, José A S; McGuire, Phillip; Krystal, John H; Baker, Glen B; Zuardi, Antonio W

2011-01-15

Interactions between glutamatergic and endocannabinoid systems may contribute to schizophrenia, dissociative states, and other psychiatric conditions. Cannabidiol (CBD), a cannabinoid-1/2 (CB1/2) receptor weak partial agonist or antagonist, may play a role in the treatment of schizophrenia. This study tested the hypothesis that CBD would attenuate the behavioral effects of the NMDA receptor antagonist, ketamine, in healthy human subjects. Ten male healthy volunteers were evaluated twice in a randomized order. In both sessions they received ketamine (bolus of 0.26 mg/kg/1 min followed by IV infusion of 0.25mg/kg over 30 min) preceded by either CBD (600 mg) or placebo. Psychopathology was assessed using the Brief Psychiatric Rating Scale (BPRS) and the CADSS (Clinician Administered Dissociative States Scale) at regular intervals from 30 min before to 90 min after ketamine administration. CBD significantly augmented the activating effects of ketamine, as measured by the activation subscales of the BPRS. However, CBD also showed a non-significant trend to reduce ketamine-induced depersonalization, as measured by the CADSS. These data describe a complex pattern of psychopharmacologic interactions between CBD and ketamine at the doses of each agent studied in this experiment. Copyright © 2010 Elsevier B.V. All rights reserved.

Development of a checklist of short-term and long-term psychological symptoms associated with ketamine use.

PubMed

Fan, Ni; Xu, Ke; Ning, Yuping; Wang, Daping; Ke, Xiaoyin; Ding, Yi; Sun, Bin; Zhou, Chao; Deng, Xuefeng; Rosenheck, Robert; He, Hongbo

2015-06-25

Ketamine is an increasingly popular drug of abuse in China but there is currently no method for classifying the psychological effects of ketamine in individuals with ketamine dependence. Develop a scale that characterizes the acute and long-term psychological effects of ketamine use among persons with ketamine dependence. We developed a preliminary symptom checklist with 35 dichotomous ('yes' or 'no') items about subjective feelings immediately after ketamine use and about perceived long-term effects of ketamine use that was administered to 187 inpatients with ketamine dependence recruited from two large hospitals in Guangzhou, China. Exploratory factor analysis (EFA) was conducted on a randomly selected half of thesample to reduce the items and to identify underlying constructs. Confirmatory factor analysis (CFA) was conducted on the second half of the sample to assess the robustness of the identified factor structure. Among the 35 symptoms, the most-reported acute effects were 'floating or circling' (94%), 'euphoric when listening to rousing music' (86%), and 'feeling excited, talkative, and full of energy' (67%). The mostreported long-term symptoms were 'memory impairment' (93%), 'personality changes' (86%), and 'slowed reactions' (81%). EFA resulted in a final 22-item scale best modelled by a four-factor model: two factors representing chronic symptoms (social withdrawal and sleep disturbances), one about acute psychoticlike symptoms, and one that combined acute drug-related euphoria and longer-term decreased libido. CFA showed that these 4 factors accounted for 50% of the total variance of the final 22-item scale and that the model fit was fair (Goodness of Fit Index, GIF=83.3%; Root Mean Square Error of Approximation, RMSEA=0.072). A four-factor model including social withdrawal, sleep disturbance, psychotic-like symptoms, and euphoria at the time of drug use provides a fair description of the short-term and long-term psychological symptoms associated with ketamine use. Future work on the 22-item version of the scale with larger samples is needed to confirm the validity of this 4-factor structure, to assess the scale's test-retest reliability, and to determine whether or not it can be useful in the differential diagnosis and monitoring of treatment of individuals with ketamine dependence.

Intranasal ketamine for acute traumatic pain in the Emergency Department: a prospective, randomized clinical trial of efficacy and safety.

PubMed

Shimonovich, Shachar; Gigi, Roy; Shapira, Amir; Sarig-Meth, Tal; Nadav, Danielle; Rozenek, Mattan; West, Debra; Halpern, Pinchas

2016-11-09

Ketamine has been well studied for its efficacy as an analgesic agent. However, intranasal (IN) administration of ketamine has only recently been studied in the emergency setting. The objective of this study was to elucidate the efficacy and adverse effects of a sub-dissociative dose of IN Ketamine compared to IV and IM morphine. A single-center, randomized, prospective, parallel clinical trial of efficacy and safety of IN ketamine compared to IV and IM morphine for analgesia in the emergency department (ED). A convenience sample of 90 patients aged 18-70 experiencing moderate-severe acute traumatic pain (≥80 mm on 100 mm Visual Analog Scale [VAS]) were randomized to receive either 1.0 mg/kg IN ketamine, 0.1 mg/kg IV MO or 0.15 mg/kg IM MO. Pain relief and adverse effects were recorded for 1 h post-administration. The primary outcome was efficacy of IN ketamine compared to IV and IM MO, measured by "time-to-onset" (defined as a ≥15 mm pain decrease on VAS), as well as time to and degree of maximal pain reduction. The 3 study groups showed a highly significant, similar maximal pain reduction of 56 ± 26 mm for IN Ketamine, and 59 ± 22 and 48 ± 30 for IV MO and IM MO, respectively. IN Ketamine provided clinically-comparable results to those of IV MO with regards to time to onset (14.3 ± 11.2 v. 8.9 ± 5.6 min, respectively) as well as in time to maximal pain reduction (40.4 ± 16.3) versus (33.4 ± 18), respectively. IN ketamine shows efficacy and safety comparable to IV and IM MO. Given the benefits of this mode of analgesia in emergencies, it should be further studied for potential clinical applications. Retrospectively registered on 27 June 2016. ClinicalTrials.gov ID: NCT02817477.

Effects of ketamine and N-methyl-D-aspartate on fluoxetine-induced antidepressant-related behavior using the forced swimming test.

PubMed

Owolabi, Rotimi Adegbenga; Akanmu, Moses Atanda; Adeyemi, Oluwole Isaac

2014-04-30

This study investigated the effects of ketamine on fluoxetine-induced antidepressant behavior using the forced swimming test (FST) in mice. In order to understand the possible role of N-methyl-d-aspartate (NMDA) neurotransmission in the antidepressant effect of fluoxetine, different groups of mice (n=10) were administered with acute ketamine (3mg/kg, i.p.), acute NMDA (75mg/kg and 150mg/kg, i.p.) and a 21-day chronic ketamine (15mg/kg, i.p./day) were administered prior to the administration of fluoxetine (20mg/kg, i.p.) in the mice. Antidepressant related behavior (immobility score) was measured using the forced swimming test. The results showed that the acute ketamine and fluoxetine alone treatments elicited a significant (p<0.05) reduction in immobility score compared with saline control. Furthermore, pre-treatment with acute ketamine significantly enhanced by the fluoxetine-induced decrease in immobility score. In contrast, pre-treatment with NMDA (150mg/kg) significantly (p<0.05) reversed fluoxetine-induced decrease in immobility score. On the other hand, chronic administration of ketamine significantly elicited an increase in immobility score as well as reversed the reduction induced by fluoxetine. Similarly, NMDA administration at both 75mg/kg and 150mg/kg increased immobility score in chronically administered ketamine groups. Furthermore, chronic administration of ketamine, followed by NMDA (75mg/kg) and fluoxetine significantly elevated the immobility score when compared with the group that received NMDA and fluoxetine but not chronically treated with ketamine. It can be suggested) that facilitation of NMDA transmission blocked fluoxetine-induced reduction in immobility score, while down-regulation of NMDA transmission is associated with increase in fluoxetine-induced antidepressant-related behavior in mice. Down-regulation of the NMDA transmission is proposed as an essential component of mechanism of suppression of depression related behaviors by fluoxetine. Modulation of NMDA transmission is suggested to be relevant in the mechanism of action of fluoxetine. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Delayed increase of thrombocyte levels after a single sub-anesthetic dose of ketamine - A randomized trial.

PubMed

Colic, Lejla; Woelfer, Marie; Colic, Merima; Leutritz, Anna Linda; Liebe, Thomas; Fensky, Luisa; Sen, Zumrut Duygu; Li, Meng; Hoffmann, Juliane; Kretzschmar, Moritz A; Isermann, Berend; Walter, Martin

2018-04-23

Recently, ketamine has been investigated as a potential antidepressant option for treatment resistant depression. Unlike traditional drugs, it yields immediate effects, most likely via increased glutamatergic transmission and synaptic plasticity. However, ketamine administration in humans is systemic and its long-term impact on blood parameters has not yet been described in clinical studies. Here we investigated potential sustained effects of ketamine administration (0.5 mg/kg ketamine racemate) on hematological and biochemical values in plasma and serum in a randomized double-blinded study. 80 healthy young participants were included and whole blood samples were collected 5 days before, and 14 days after the infusion. To assess the group effect, repeated measure analyses of co-variance (rmANCOVA) were conducted for the following blood parameters: levels of sodium, potassium, calcium, hemoglobin and number of erythrocytes, lymphocytes, and thrombocytes. RmANCOVA revealed a significant time by treatment effect on thrombocyte levels (F 1, 74 = 13.54, p < 0.001, eta = 0.155), driven by an increase in the ketamine group (paired t-test, t = -3.51, df = 38, p = 0.001). Specificity of thrombocyte effect was confirmed by logistic regression, and in addition, no other coagulation parameters showed significant interaction. Moreover, the relative increase in the ketamine group was stable across sexes and not predicted by age, BMI, smoking, alcohol or drug use, and contraception. Our results describe aftereffects of sub-anesthetic ketamine administration on blood coagulation parameters, which should be considered especially when targeting psychiatric populations with relevant clinical comorbidities. Copyright © 2018 Elsevier B.V. and ECNP. All rights reserved.

Effects of co-administration of ketamine and ethanol on the dopamine system via the cortex-striatum circuitry.

PubMed

Liu, Qing; Xu, Tian-Yong; Zhang, Zhi-Bi; Leung, Chi-Kwan; You, Ding-Yun; Wang, Shang-Wen; Yi, Shuai; Jing, Qiang; Xie, Run-Fang; Li, Huifang-Jie; Zeng, Xiao-Feng

2017-06-15

Ketamine and ethanol are increasingly being used together as recreational drugs in rave parties. Their effects on the dopamine (DA) system remain largely unknown. This study aimed to investigate the effects of consuming two different concentrations of ketamine with and without alcohol on the DA system. We employed the conditioned place preference (CPP) paradigm to evaluate the rewarding effects of the combined administration of two different doses of ketamine (30mg/kg and 60mg/kg) with ethanol (0.3156g/kg). We evaluated the effects of the combined drug treatment on the transcriptional output of tyrosine hydroxylase (TH), dopa decarboxylase (DDC), synaptosomal-associated protein 25 (SNAP25), and vesicular monoamine transporter 2 (VMAT2) as well as protein expression level of brain-derived neurotrophic factor (BDNF) in rat prefrontal cortex (PFC) and striatum. We found that rats exhibited a dose-dependent, drug-paired, place preference to ketamine and ethanol associated with an elevated DA level in the striatum but not in the PFC. Moreover, treatment involving low- or high-dose ketamine with or without ethanol caused a differential regulatory response in the mRNA levels of the four DA metabolism genes and the cellular protein abundance of BDNF via the cortex-striatum circuitry. This study investigated the molecular mechanisms that occur following the combined administration of ketamine and ethanol in the DA system, which could potentially lead to alterations in the mental status and behavior of ketamine/ethanol users. Our findings may aid the development of therapeutic strategies for substance abuse patients. Copyright © 2017 Elsevier Inc. All rights reserved.

Anhedonia as a clinical correlate of suicidal thoughts in clinical ketamine trials.

PubMed

Ballard, Elizabeth D; Wills, Kathleen; Lally, Níall; Richards, Erica M; Luckenbaugh, David A; Walls, Tessa; Ameli, Rezvan; Niciu, Mark J; Brutsche, Nancy E; Park, Lawrence; Zarate, Carlos A

2017-08-15

Identifying clinical correlates associated with reduced suicidal ideation may highlight new avenues for the treatment of suicidal thoughts. Anhedonia occurs across psychiatric diagnoses and has been associated with specific neural circuits in response to rapid-acting treatments, such as ketamine. This analysis sought to evaluate whether reductions in suicidal ideation after ketamine administration were related to reduced levels of anhedonia, independent of depressive symptoms. This post-hoc analysis included treatment-resistant patients with either major depressive disorder (MDD) or bipolar disorder (BD) from several clinical trials of ketamine. Anhedonia was assessed using a subscale of the Beck Depression Inventory (BDI) and the Snaith-Hamilton Pleasure Scale (SHAPS). The outcome of interest was suicidal ideation, as measured by a subscale of the Scale for Suicide Ideation (SSI5), one day post-ketamine administration. Anhedonia, as measured by the SHAPS, was associated with suicidal thoughts independent of depressive symptoms both before and after ketamine administration. One day post-ketamine administration, improvements on the SHAPS accounted for an additional 13% of the variance in suicidal thought reduction, beyond the influence of depressive symptoms. The BDI anhedonia subscale was not significantly associated with suicidal thoughts after adjusting for depressive symptoms. Data were limited to patients experiencing a major depressive episode and may not be generalizable to patients experiencing an active suicidal crisis. Suicidal thoughts may be related to symptoms of anhedonia independent of other depressive symptoms. These results have implications for the potential mechanisms of action of ketamine on suicidal thoughts. Published by Elsevier B.V.

Pilot Randomized Controlled Trial of Titrated Subcutaneous Ketamine in Older Patients with Treatment-Resistant Depression.

PubMed

George, Duncan; Gálvez, Verònica; Martin, Donel; Kumar, Divya; Leyden, John; Hadzi-Pavlovic, Dusan; Harper, Simon; Brodaty, Henry; Glue, Paul; Taylor, Rohan; Mitchell, Philip B; Loo, Colleen K

2017-11-01

To assess the efficacy and safety of subcutaneous ketamine for geriatric treatment-resistant depression. Secondary aims were to examine if repeated treatments were safe and more effective in inducing or prolonging remission than a single treatment. In this double-blind, controlled, multiple-crossover study with a 6-month follow-up (randomized controlled trial [RCT] phase), 16 participants (≥60 years) with treatment-resistant depression who relapsed after remission or did not remit in the RCT were administered an open-label phase. Up to five subcutaneous doses of ketamine (0.1, 0.2, 0.3, 0.4, and 0.5 mg/kg) were administered in separate sessions (≥1 week apart), with one active control (midazolam) randomly inserted (RCT phase). Twelve ketamine treatments were given in the open-label phase. Mood, hemodynamic, and psychotomimetic outcomes were assessed by blinded raters. Remitters in each phase were followed for 6 months. Seven of 14 RCT-phase completers remitted with ketamine treatment. Five remitted at doses below 0.5 mg/kg. Doses ≥ 0.2 mg/kg were significantly more effective than midazolam. Ketamine was well tolerated. Repeated treatments resulted in higher likelihood of remission or longer time to relapse. Results provide preliminary evidence for the efficacy and safety of ketamine in treating elderly depressed. Dose titration is recommended for optimizing antidepressant and safety outcomes on an individual basis. Subcutaneous injection is a practical method for giving ketamine. Repeated treatments may improve remission rates (clinicaltrials.gov; NCT01441505). Copyright © 2017 American Association for Geriatric Psychiatry. All rights reserved.

Electroconvulsive therapy-induced persistent retrograde amnesia: could it be minimised by ketamine or other pharmacological approaches?

PubMed

Gregory-Roberts, Emily M; Naismith, Sharon L; Cullen, Karen M; Hickie, Ian B

2010-10-01

Certain pharmacological agents administered during electroconvulsive therapy may have the potential to prevent persistent retrograde amnesia induced during electroconvulsive therapy. This review examines mechanisms for electroconvulsive therapy-induced retrograde amnesia, and evaluates the suitability of the anaesthetic ketamine for preventing this amnestic outcome. A review of human studies, animal models and theoretical models in light of memory dysfunction following electroconvulsive therapy was conducted. MEDLINE was searched from 1950 to April 2009 using the MeSH terms "electroconvulsive therapy", "memory", "memory short term", "memory disorders", "excitatory amino acid antagonists", and "ketamine". PREMEDLINE was searched using the terms "electroconvulsive therapy", "amnesia" and "ketamine". Additional keyword and reference list searches were performed. No language, date constraints or article type constraints were used. Disruption of long term potentiation as a mechanism for electroconvulsive therapy-induced retrograde amnesia is well supported. Based on this putative mechanism, an N-methyl-D-aspartate receptor antagonist would appear suitable for preventing the retrograde amnesia. Available evidence in animals and humans supports the prediction that ketamine, an anaesthetic agent and N-methyl-D-aspartate receptor antagonist, could effectively prevent electroconvulsive therapy-induced persistent retrograde amnesia. Whilst there are concerns about the use of ketamine with electroconvulsive therapy, such as possible psychotomimetic effects, on balance this anaesthetic agent may improve or hasten clinical response to electroconvulsive therapy. A clinical trial is warranted to determine if ketamine anaesthesia during electroconvulsive therapy can lessen persistent retrograde amnesia and improve therapeutic response. Electroconvulsive therapy with ketamine anaesthesia may provide effective antidepressant action with minimal side effects. Copyright 2009 Elsevier B.V. All rights reserved.

Chronic Ketamine Exposure Causes White Matter Microstructural Abnormalities in Adolescent Cynomolgus Monkeys.

PubMed

Li, Qi; Shi, Lin; Lu, Gang; Yu, Hong-Luan; Yeung, Fu-Ki; Wong, Nai-Kei; Sun, Lin; Liu, Kai; Yew, David; Pan, Fang; Wang, De-Feng; Sham, Pak C

2017-01-01

Acute and repeated exposures to ketamine mimic aspects of positive, negative, and cognitive symptoms of schizophrenia in humans. Recent studies by our group and others have shown that chronicity of ketamine use may be a key element for establishing a more valid model of cognitive symptoms of schizophrenia. However, current understanding on the long-term consequences of ketamine exposure on brain circuits has remained incomplete, particularly with regard to microstructural changes of white matter tracts that underpin the neuropathology of schizophrenia. Thus, the present study aimed to expand on previous investigations by examining causal effects of repeated ketamine exposure on white matter integrity in a non-human primate model. Ketamine or saline (control) was administered intravenously for 3 months to male adolescent cynomolgus monkeys ( n = 5/group). Diffusion tensor imaging (DTI) experiments were performed and tract-based spatial statistics (TBSS) was used for data analysis. Fractional anisotropy (FA) was quantified across the whole brain. Profoundly reduced FA on the right side of sagittal striatum, posterior thalamic radiation (PTR), retrolenticular limb of the internal capsule (RLIC) and superior longitudinal fasciculus (SLF), and on the left side of PTR, middle temporal gyrus and inferior frontal gyrus were observed in the ketamine group compared to controls. Diminished white matter integrity found in either fronto-thalamo-temporal or striato-thalamic connections with tracts including the SLF, PTR, and RLIC lends support to similar findings from DTI studies on schizophrenia in humans. This study suggests that chronic ketamine exposure is a useful pharmacological paradigm that might provide translational insights into the pathophysiology and treatment of schizophrenia.

Long-Term Stability of Tramadol and Ketamine Solutions for Patient-Controlled Analgesia Delivery.

PubMed

Gu, Junfeng; Qin, Wengang; Chen, Fuchao; Xia, Zhongyuan

2015-08-26

Subanesthetic doses of ketamine as an adjuvant to tramadol in patient-controlled analgesia (PCA) for postoperative pain have been shown to improve the quality of analgesia. However, there are no such commercially available drug mixtures, and the stability of the combination has rarely been assessed. Admixtures were assessed for periods of up to 14 days at 4°C and 25°C. Three different mixtures of tramadol and ketamine (tramadol 5.0 mg/mL + ketamine 0.5 mg/mL, tramadol 5.0 mg/mL + ketamine 1.0 mg/mL, and tramadol 5.0 mg/mL + ketamine 2.0 mg/mL) were prepared in polyolefin bags by combining these 2 drugs with 0.9% sodium chloride (normal saline [NS]). The chemical stability of the admixtures was evaluated by a validated high-performance liquid chromatography (HPLC) method and by measurement of pH values. Solution appearance and color were assessed by observing the samples against black and white backgrounds. Solutions were considered stable if they maintained 90% of the initial concentration of each drug. The percentages of initial concentration of tramadol and ketamine in the various solutions remained above 98% when stored at 4°C or 25°C over the testing period. No changes in color or turbidity were observed in any of the prepared solutions. Throughout this period, pH values remained stable. The results indicate that the drug mixtures of tramadol with ketamine in NS for PCA delivery systems were stable for 14 days when stored in polyolefin bags at 4°C or 25°C.

Low-Dose Ketamine Infusions for Highly Opioid-Tolerant Adults Following Spinal Surgery: A Retrospective Before-and-after Study.

PubMed

Vaid, Patrycja; Green, Theresa; Shinkaruk, Kelly; King-Shier, Kathryn

2016-04-01

Managing acute-on-chronic pain in opioid-tolerant individuals is complex and challenging; exploring new analgesia regimens for this population is essential. Ketamine is an N-methyl D-aspartate antagonist that blocks transmission of painful stimuli and could be a useful medication for this patient population. A new low-dose ketamine protocol as an adjunct to conventional pain therapy was implemented in a major urban Level 1 trauma center in Canada. A retrospective before-and-after chart review was conducted to explore the research question, "What is the effect of low-dose ketamine continuous intravenous infusions on pain of highly opioid-tolerant adults following spinal surgery?". All patients had spine surgery, used a minimum of 100 mg daily oral morphine equivalent preoperatively and were followed postoperatively by the hospital's Acute Pain Service. Data from individuals treated with conventional therapy during the year prior to protocol implementation were compared with data from patients who received conventional therapy plus ketamine post implementation. Outcome measures included pain scores and daily opioid consumption on postoperative days 0 through 5, time to ambulation, time to discharge, and adverse effects. There were no statistically significant differences between conventional therapy and conventional therapy plus ketamine. Ketamine may still be of benefit to patients with acute-on-chronic pain, although this was not evident in this study. Future research using more robust assessment tools to determine effectiveness of ketamine is required. Copyright © 2016 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Increase in PAS-induced neuroplasticity after a treatment course of intranasal ketamine for depression. Report of three cases from a placebo-controlled trial.

PubMed

Gálvez, Verònica; Nikolin, Stevan; Ho, Kerrie-Anne; Alonzo, Angelo; Somogyi, Andrew A; Loo, Colleen K

2017-02-01

Animal studies suggest that neural plasticity may play a role in the antidepressant effects of a single ketamine dose. However, the potential effects of repeated ketamine treatments on human neuroplasticity are unknown. This pilot RCT study measured plasticity-induced changes before and after a ketamine course, in three treatment-resistant depressed subjects, who were randomized to receive 8 intranasal treatments of 100mg ketamine or 4.5mg midazolam. Mood ratings were performed by a trained blinded rater at baseline and 24h-48h after the ketamine course, using the Montgomery Asberg Depression Rating Scale (MADRS). Neuroplasticity was assessed in the motor cortex using a paired associative stimulation (PAS) paradigm at baseline and 24h-48h after the treatment course. No changes in current psychotropic medication or dosage were permitted for 4weeks prior to trial entry and throughout the trial. The subject receiving ketamine, but not those receiving midazolam, presented a marked increase in neural plasticity after the treatment course. However, mood changes were not associated with changes in neural plasticity. Pilot study with small sample size. Concomitant antidepressant medications taken. Plasticity was tested in the motor cortex only, thus the generalizability of these findings to other brain areas cannot be assumed. These results suggest that a course of intranasal ketamine may enhance synaptic plasticity in subjects with depression, but this was not associated with antidepressant effects. Further research on this topic is warranted. Copyright © 2016 Elsevier Inc. All rights reserved.

21 CFR 522.23 - Acepromazine.

Code of Federal Regulations, 2013 CFR

2013-04-01

... sponsors in § 510.600(c) of this chapter: (1) No. 000010 for use as in paragraphs (d) and (e) of this section. (2) No. 000859 for use as in paragraph (d) of this section. (c) Special considerations. Federal.... It is used in dogs, cats, and horses as follows: (1) Amount. Dogs: 0.25 to 0.5 mg per pound (/lb) of...

21 CFR 522.23 - Acepromazine.

Code of Federal Regulations, 2012 CFR

2012-04-01

... sponsors in § 510.600(c) of this chapter: (1) No. 000010 for use as in paragraphs (d) and (e) of this section. (2) No. 059130 for use as in paragraph (d) of this section. (c) Special considerations. Federal.... It is used in dogs, cats, and horses as follows: (1) Amount. Dogs: 0.25 to 0.5 mg per pound (/lb) of...

Application of carvedilol in a dog with pseudoephedrine toxicosis-induced tachycardia.

PubMed

Kang, Min-Hee; Park, Hee-Myung

2012-07-01

A 15-year-old Yorkshire terrier dog was presented after ingesting 1 capsule of an over-the-counter cold medication containing pseudoephedrine (120 mg/capsule) and cetirizine (5 mg/capsule). Treatment was initiated with acepromazine and carvedilol. The dog responded well to treatment. This is the first known case report using carvedilol to control pseudoephedrine toxicosis.

Sympathoadrenal responses to cold and ketamine anesthesia in the rhesus monkey

NASA Technical Reports Server (NTRS)

Kolka, M. A.; Elizondo, R. S.; Weinberg, R. P.

1983-01-01

The effect of cold exposure on the sympathoadrenal system is investigated in eight adult rhesus monekys with and without ketamine anesthesia. It is found that a 3 hr cold exposure (12 c) was associated with a 175 percent increase above control levels of norepinephrine (NE) and a 100 percent increase in epinephrine (E). Also observed were decreases in the core temperature, mean skin temperature, and mean body temperature. No change in the plasma levels of NE and E from the control values was found during continuous infusion of ketamine; while the core temperature, mean skin temperature, and mean body temperature all showed greater declines with the addition of ketamine infusion to the cold exposure. Water exposure (28 C) under ketamine anesthesia resulted in a reduction of the core temperature to 33 C within 1 hr. Plasma levels of NE and E were found to be unchanged from control values at core temperatures of 35 and 33 C. It is concluded that the administration of ketamine abolishes both the thermoregulatory response and the catecholamine response to acute cold exposure.

Allergic Reaction to Ketamine as Monotherapy for Procedural Sedation.

PubMed

Nguyen, Tammy T; Baker, Bethany; Ferguson, Jeffrey D

2017-04-01

Ketamine is a cyclohexamine derivative that acts as a noncompetitive N-methyl D-aspartate receptor antagonist. Its use for procedural sedation is recommended by national clinical policy. However, its immunogenic potential is not well documented. We report a case of allergic reaction associated with the administration of intravenous ketamine for procedural sedation in a 16-year-old male. Minutes after administration, the patient developed a morbilliform, erythematous rash that extended to the upper and lower torso and resolved with intravenous diphenhydramine. It is most likely that this allergic reaction was caused by a ketamine-induced histamine release that has been described in vitro. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This is the first case report in which ketamine was used as monotherapy in the emergency department for the facilitation of procedural sedation that resulted in an allergic reaction. Supportive measures, including advanced airway procedures and hemodynamic support, may be necessary in more severe anaphylactic cases. Providers should be aware of this potential adverse effect when using ketamine for procedural sedation. Copyright © 2016 Elsevier Inc. All rights reserved.

Ketamine-Based Anesthetic Protocols and Evoked Potential Monitoring: A Risk/Benefit Overview

PubMed Central

Stoicea, Nicoleta; Versteeg, Gregory; Florescu, Diana; Joseph, Nicholas; Fiorda-Diaz, Juan; Navarrete, Víctor; Bergese, Sergio D.

2016-01-01

Since its discovery, ketamine, a non-competitive N-methyl D-aspartate (NMDA) receptor antagonist related to phencyclidine, has been linked to multiple adverse reactions sometimes described as “out of body” and “near death experiences,” including emergence phenomena, delusions, hallucinations, delirium, and confusion. Due to these effects, ketamine has been withdrawn from mainstream anesthetic use in adult patients. Evoked potentials (EPs) are utilized to monitor neural pathways during surgery, detect intraoperative stress or damage, detect and define the level of neural lesions, and define abnormalities. Unfortunately, many of the volatile anesthetics commonly used during spinal and neurologic procedures suppress EP amplitude and monitoring. Ketamine has been found in several preclinical and clinical studies to actually increase EP amplitude and thus has been used as an analgesic adjunct in procedures where EP monitoring is critical. Once the gap in our knowledge of ketamine's risks has been sufficiently addressed in animal models, informed clinical trials should be conducted in order to properly incorporate ketamine-based anesthetic regimens during EP-monitored neurosurgeries. PMID:26909017

Effects of Combined Ketamine/Xylazine Anesthesia on Light Induced Retinal Degeneration in Rats

PubMed Central

Bolz, Sylvia; Eslava-Schmalbach, Javier; Willmann, Gabriel; Zhour, Ahmad; Zrenner, Eberhart; Fischer, M. Dominik; Gekeler, Florian

2012-01-01

Objectives To explore the effect of ketamine-xylazine anesthesia on light-induced retinal degeneration in rats. Methods Rats were anesthetized with ketamine and xylazine (100 and 5 mg, respectively) for 1 h, followed by a recovery phase of 2 h before exposure to 16,000 lux of environmental illumination for 2 h. Functional assessment by electroretinography (ERG) and morphological assessment by in vivo imaging (optical coherence tomography), histology (hematoxylin/eosin staining, TUNEL assay) and immunohistochemistry (GFAP and rhodopsin staining) were performed at baseline (ERG), 36 h, 7 d and 14 d post-treatment. Non-anesthetized animals treated with light damage served as controls. Results Ketamine-xylazine pre-treatment preserved retinal function and protected against light-induced retinal degeneration. In vivo retinal imaging demonstrated a significant increase of outer nuclear layer (ONL) thickness in the non-anesthetized group at 36 h (p<0.01) and significant reduction one week (p<0.01) after light damage. In contrast, ketamine-xylazine pre-treated animals showed no significant alteration of total retinal or ONL thickness at either time point (p>0.05), indicating a stabilizing and/or protective effect with regard to phototoxicity. Histology confirmed light-induced photoreceptor cell death and Müller cells gliosis in non-anesthetized rats, especially in the superior hemiretina, while ketamine-xylazine treated rats showed reduced photoreceptor cell death (TUNEL staining: p<0.001 after 7 d), thicker ONL and longer IS/OS. Fourteen days after light damage, a reduction of standard flash induced a-wave amplitudes and a-wave slopes (p = 0.01) and significant alterations in parameters of the scotopic sensitivity function (e.g. Vmax of the Naka Rushton fit p = 0.03) were observed in non-treated vs. ketamine-xylazine treated animals. Conclusions Our results suggest that pre-treatment with ketamine-xylazine anesthesia protects retinas against light damage, reducing photoreceptor cell death. These data support the notion that anesthesia with ketamine-xylazine provides neuroprotective effects in light-induced cell damage. PMID:22558200

“Resting” CBF in the Epileptic Baboon: Correlation with Ketamine Dose and Interictal Epileptic Discharges

PubMed Central

Szabó, C. Ákos; Narayana, Shalini; Franklin, Crystal; Knape, Koyle D.; Davis, M. Duff; Fox, Peter T.; Leland, M. Michelle; Williams, Jeff T.

2011-01-01

Background Photosensitive epileptic (SZ) baboons demonstrate different cerebral blood flow (CBF) activation patterns from asymptomatic controls (CTL) during intermittent light stimulation (ILS). This study compares “resting” CBF between PS and CTL animals, and CBF correlations with ketamine dose and interictal epileptic discharges (IEDs) between PS and CTL animals. Methods Continuous intravenous ketamine was administered to eight PS and eight CTL baboons (matched for gender and weight), and maintained at subanesthetic doses (4.8–14.6 mg/kg/hr). Three resting H215O-PET studies were attempted in each animal (CTI/Siemens HR+ scanner). Images were acquired in 3D mode (63 contiguous slices, 2.4 mm thickness). PET images were co-registered with MRI images (3T Siemens Trio, T1-weighted 3D Turboflash sequence, TE/TR/TI = 3.04/2100/785 msec, flip angle=13 degrees). EEG was used to monitor depth of sedation and for quantification of IED rates. Regional CBF was compared between PS and CTL groups and correlations were analyzed for ketamine dose and IED rates. Results When subsets of animals of either group, receiving similar doses of ketamine were compared, PS animals demonstrated relative CBF increases in the occipital lobes and decreases in the frontal lobes. Correlation analyses with ketamine dose confirmed the frontal and occipital lobe changes in the PS animals. The negative correlations of CBF with ketamine dose and IED rate overlapped frontally. While frontal lobe CBF was also negatively correlated with IED rate, positive correlations were found in the parietal lobe. Conclusions “Resting” CBF differs between PS and CTL baboons. Correlation analyses of CBF and ketamine dose reveal that occipital lobe CBF increases and frontal lobe in PS animals are driven by ketamine. While frontal lobe CBF decreases may be related to ketamine’s propensity to activate IEDs, positive CBF correlations with IED rate suggest involvement of the parietal lobes in their generation. PMID:18801644

'Special K' and a Loss of Cell-To-Cell Adhesion in Proximal Tubule-Derived Epithelial Cells: Modulation of the Adherens Junction Complex by Ketamine

PubMed Central

Hills, Claire E.; Jin, Tianrong; Siamantouras, Eleftherios; Liu, Issac K-K; Jefferson, Kieran P.; Squires, Paul E.

2013-01-01

Ketamine, a mild hallucinogenic class C drug, is the fastest growing ‘party drug’ used by 16–24 year olds in the UK. As the recreational use of Ketamine increases we are beginning to see the signs of major renal and bladder complications. To date however, we know nothing of a role for Ketamine in modulating both structure and function of the human renal proximal tubule. In the current study we have used an established model cell line for human epithelial cells of the proximal tubule (HK2) to demonstrate that Ketamine evokes early changes in expression of proteins central to the adherens junction complex. Furthermore we use AFM single-cell force spectroscopy to assess if these changes functionally uncouple cells of the proximal tubule ahead of any overt loss in epithelial cell function. Our data suggests that Ketamine (24–48 hrs) produces gross changes in cell morphology and cytoskeletal architecture towards a fibrotic phenotype. These physical changes matched the concentration-dependent (0.1–1 mg/mL) cytotoxic effect of Ketamine and reflect a loss in expression of the key adherens junction proteins epithelial (E)- and neural (N)-cadherin and β-catenin. Down-regulation of protein expression does not involve the pro-fibrotic cytokine TGFβ, nor is it regulated by the usual increase in expression of Slug or Snail, the transcriptional regulators for E-cadherin. However, the loss in E-cadherin can be partially rescued pharmacologically by blocking p38 MAPK using SB203580. These data provide compelling evidence that Ketamine alters epithelial cell-to-cell adhesion and cell-coupling in the proximal kidney via a non-classical pro-fibrotic mechanism and the data provides the first indication that this illicit substance can have major implications on renal function. Understanding Ketamine-induced renal pathology may identify targets for future therapeutic intervention. PMID:24009666

[Assessment of the use of racemic ketamine and its S(+) isomer, associated or not with low doses of fentanyl, in balneotherapy for major burn patients].

PubMed

Cantinho, Fernando Antônio de Freitas; Silva, Antonio Carlos Pereira da

2009-01-01

The care of the wounds of major burn patients triggers severe painful stimuli. The objective of this study was to assess the safety and efficacy of different drug combinations in anesthesia for balneotherapy. After approval by the Ethics Commission, 200 procedures of balneotherapy in 87 major burn adult patients were evaluated. Midazolam was used in all cases. The vials of ketamine were numbered and, therefore, at the time of the use, one did not know whether racemic or S(+)ketamine was being used. Each morning it was decided by drawing lots whether fentanyl would be used or not in the procedures of that day. Patients were included in one of four groups: ISO/sf (S(+) isomer without fentanyl), ISO/cf (S(+) isomer with fentanyl), RAC/sf (racemic ketamine without fentanyl), and RAC/cf (racemic ketamine with fentanyl). The initial doses proposed were as follows: midazolam, 0.06 mg.kg-1; ketamine, 1.0 to 1.1 mg.kg-1; and fentanyl, 0.8 (1/4)g.kg1-1; additional doses were administered as needed. Only one patient recalled the pain of balneotherapy. In the group that received S(+)ketamine, the use of fentanyl did not bring additional advantages; however, when associated with racemic ketamine, fentanyl reduced the total dose and the number of ketamine boluses. The extension of body surface burned was the main determinant of the severity of post-procedure pain. Reduced pain severity was the main factor considered by patients when grading their satisfaction with the anesthesia. The four different drug combinations proved to be safe and guaranteed the absence of pain during balneotherapy. Characteristics not directly related to the anesthetics proved to be more important in the incidence of post-procedure pain, which was the main factor considered by major burn patient to define their satisfaction with the anesthesia used.

Is pre-emptive administration of ketamine a significant adjunction to intravenous morphine analgesia for controlling postoperative pain? A randomized, double-blind, placebo-controlled clinical trial.

PubMed

Fiorelli, Alfonso; Mazzella, Antonio; Passavanti, Beatrice; Sansone, Pasquale; Chiodini, Paolo; Iannotti, Mario; Aurilio, Caterina; Santini, Mario; Pace, Maria Caterina

2015-09-01

To evaluate if the pre-emptive administration of ketamine would potentiate the effect of intravenous morphine analgesia in the management of post-thoracotomy pain. This was a unicentre, double-blind, placebo-controlled, parallel-group, prospective study. Patients were randomly assigned to receive 1 mg/kg ketamine (ketamine group) or an equivalent dose of normal saline (placebo group) before thoracotomy in 1:1 ratio. All patients received postoperatively intravenous morphine administration as additional analgesic regimen. Primary end-point was the pain relief measured with Visual Analogue Scale at rest. The secondary end-points were the reduction of inflammatory response expressed by plasma C-reactive protein levels, the morphine consumption and the rate of side effects. The measurements were carried out 6, 12, 24, 36 and 48 hours postoperatively. A total of 75 patients were randomized of whom 38 were allocated to ketamine group and 37 to placebo group. Baseline characteristics were comparable. Ketamine compared with placebo group showed a significant reduction of pain scores (P = 0.01), C-reactive protein (P < 0.001) and morphine consumption (P < 0.001). No acute psychological side effects related to the use of ketamine were registered. The administration of ketamine before surgery may be an effective adjunct to intravenous morphine analgesia in acute post-thoracotomy pain management. In ketamine group, satisfaction of pain relief was significantly higher with a significant reduction of inflammatory response and morphine consumption compared with placebo group. Our results, if confirmed by larger studies, may be of clinical relevance in situations where epidural analgesia or other analgesic procedures different from systemic opioid analgesia are unavailable or contraindicated. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Adjunct Ketamine Use in the Management of Severe Ethanol Withdrawal.

PubMed

Pizon, Anthony F; Lynch, Michael J; Benedict, Neal J; Yanta, Joseph H; Frisch, Adam; Menke, Nathan B; Swartzentruber, Greg S; King, Andrew M; Abesamis, Michael G; Kane-Gill, Sandra L

2018-05-08

Ketamine offers a plausible mechanism with favorable kinetics in treatment of severe ethanol withdrawal. The purpose of this study is to determine if a treatment guideline using an adjunctive ketamine infusion improves outcomes in patients suffering from severe ethanol withdrawal. Retrospective observational cohort study. Academic tertiary care hospital. Patients admitted to the ICU and diagnosed with delirium tremens by Diagnostic and Statistical Manual of Mental Disorders V criteria. Pre and post guideline, all patients were treated in a symptom-triggered fashion with benzodiazepines and/or phenobarbital. Postguideline, standard symptom-triggered dosing continued as preguideline, plus, the patient was initiated on an IV ketamine infusion at 0.15-0.3 mg/kg/hr continuously until delirium resolved. Based upon withdrawal severity and degree of agitation, a ketamine bolus (0.3 mg/kg) was provided prior to continuous infusion in some patients. A total of 63 patients were included (29 preguideline; 34 postguideline). Patients treated with ketamine were less likely to be intubated (odds ratio, 0.14; p < 0.01; 95% CI, 0.04-0.49) and had a decreased ICU stay by 2.83 days (95% CI, -5.58 to -0.089; p = 0.043). For ICU days outcome, correlation coefficients were significant for alcohol level and total benzodiazepine dosing. For hospital days outcome, correlation coefficients were significant for patient age, aspartate aminotransferase, and alanine aminotransferase level. Regression revealed the use of ketamine was associated with a nonsignificant decrease in hospital stay by 3.66 days (95% CI, -8.40 to 1.08; p = 0.13). Mechanistically, adjunctive therapy with ketamine may attenuate the demonstrated neuroexcitatory contribution of N-methyl-D-aspartate receptor stimulation in severe ethanol withdrawal, reduce the need for excessive gamma-aminobutyric acid agonist mediated-sedation, and limit associated morbidity. A ketamine infusion in patients with delirium tremens was associated with reduced gamma-aminobutyric acid agonist requirements, shorter ICU length of stay, lower likelihood of intubation, and a trend toward a shorter hospitalization.

Ketamine. A solution to procedural pain in burned children.

PubMed

Groeneveld, A; Inkson, T

1992-09-01

Our experience has shown ketamine to be a safe and effective method of providing pain relief during specific procedures in burned children. It renders high doses of narcotics unnecessary and offers children the benefit of general anesthesia without the requirement of endotracheal intubation and a trip to the operating room. The response of parents and staff to the use of ketamine has been positive. Parents often experience feelings of guilt following injury to a child and are eager to employ methods that reduce their child's pain. So far, no parent has refused the administration of ketamine; some have even asked that it be used during subsequent procedures on their child. With adequate pre-procedure teaching, parents are prepared for the possible occurrence of emergent reactions and can assist in reorienting the child during recovery. Staff have found that the stress of doing painful procedures on children is reduced when ketamine is used. The procedures tend to be quicker and the predicament of working on a screaming, agitated child is eliminated. At the same time, nursing staff have had to get used to the nystagmic gaze of the children and accept that these patients are truly anesthetized even though they might move and talk. Despite the success we and others have had with ketamine, several questions about its use in burn patients remain unanswered. The literature does not answer such questions as: Which nursing measures reduce the incidence of emergent reactions? How many ketamine anesthetics can safely be administered to one individual? How does the frequency of administration relate to tolerance in a burn patient? Are there detrimental effects of frequent or long-term use? Clearly, an understanding of these questions is necessary to determine the safe boundaries of ketamine use in burn patients. Ketamine is not a panacea for the problem of pain in burned children. But it is one means of managing procedural pain, which is, after all, a significant clinical factor in treatment and recovery.

Kynurenine pathway metabolism and the neurobiology of treatment-resistant depression: Comparison of multiple ketamine infusions and electroconvulsive therapy.

PubMed

Allen, A P; Naughton, M; Dowling, J; Walsh, A; O'Shea, R; Shorten, G; Scott, L; McLoughlin, D M; Cryan, J F; Clarke, G; Dinan, T G

2018-05-01

Current first-line antidepressants can take weeks or months to decrease depressive symptoms. Low dose ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, shows potential for a more rapid antidepressant effect, with efficacy also evident in previously treatment-resistant populations. However, a greater understanding of the physiological mechanisms underlying such effects is required. We assessed the potential impact of ketamine infusion on neurobiological drivers of kynurenine pathway metabolism in major depression (HPA axis hyperactivity, inflammation) in patients with treatment-resistant depression compared to gender-matched healthy controls. Furthermore, we assessed these biomarkers before and after electroconvulsive therapy (ECT), which is currently the gold standard for management of treatment-resistant depression. As previously demonstrated, treatment with ketamine and ECT was associated with improved depressive symptoms in patients. At baseline, waking cortisol output was greater in the ECT cohort, kynurenine was greater in the ketamine cohort, and kynurenic acid was lower in patients compared to healthy controls, although inflammatory markers (IL-6, IL-8, IL-10 or IFN-γ) were similar in patients and controls. Furthermore, in patients who responded to ECT, the cortisol awakening response was decreased following treatment. Despite a trend towards reduced kynurenine concentrations in those who responded to ketamine, ketamine was not associated with significant alterations in any of the biomarkers assessed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Preventive effects of blueberry extract on behavioral and biochemical dysfunctions in rats submitted to a model of manic behavior induced by ketamine.

PubMed

Debom, Gabriela; Gazal, Marta; Soares, Mayara Sandrielly Pereira; do Couto, Carlus Augustu Tavares; Mattos, Bruna; Lencina, Claiton; Kaster, Manuella Pinto; Ghisleni, Gabriele Codenonzi; Tavares, Rejane; Braganhol, Elizandra; Chaves, Vitor Clasen; Reginatto, Flávio Henrique; Stefanello, Francieli; Spanevello, Roselia Maria

2016-10-01

The aim of the present study was to evaluate the protective effects of blueberry extract on oxidative stress and inflammatory parameters in a model of mania induced by ketamine administration in rats. Male rats were pretreated with blueberry extract (200mg/kg, once a day for 14days), lithium chloride (45mg/kg, mood stabilizer used as a positive control, twice a day for 14days), or vehicle. Between the 8th and 14th days, rats also received an injection of ketamine (25mg/kg) or vehicle. In the 15th day, thirty minutes after ketamine administration the hyperlocomotion of the animals was assessed in the open - field apparatus. Immediately after the behavioral analysis brain and blood were collected for biochemical determinations. ketamine treatment induced hyperlocomotion and oxidative damage in cerebral cortex, hippocampus and striatum such as an increase in lipid peroxidation and a decrease in the antioxidant enzymes activities (superoxide dismutase, catalase e glutatione peroxidase). Ketamine administration also increased the IL-6 levels in serum in rats. Pretreatment of rats with blueberry extract or lithium prevented the hyperlocomotion, pro - oxidant effects and inflammation induced by ketamine. Our findings suggest that blueberry consumption has a neuroprotective potential against behavioral and biochemical dysfunctions induced in a preclinical model that mimic some aspects of the manic behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

Assessment of pulse oximeter perfusion index in pediatric caudal block under basal ketamine anesthesia.

PubMed

Xu, Zifeng; Zhang, Jianhai; Shen, Hao; Zheng, Jijian

2013-01-01

Whether pulse oximeter perfusion index (PI) may be applied to detect the onset of caudal block in pediatric patients under ketamine intravenous basal anesthesia is investigated. 40 ASA I, 2-8-year-old boys scheduled for elective circumcision surgery were randomized into two groups. Group I: 20 patients were anesthetized by 2 mg·kg(-1) ketamine intravenous injection (IV) followed by caudal block using 1 mL·kg(-1) lidocaine (1%); Group II: 20 patients were anesthetized by 2 mg·kg(-1) ketamine IV only. PI on the toe in Group II decreased by 33 ± 12%, 71 ± 9% and 65 ± 8% at 1 min, 15 min, and 30 min after ketamine injection. The maximum increase in MAP and HR after ketamine IV was 11 ± 6% at 3 min and 10 ± 6% at 2 min. Compared to the PI value before caudal injection of lidocaine, PI in Group I increased by 363 ± 318% and 778 ± 578% at 5 min and 20 min after caudal block, while no significant changes in MAP and HR were found compared to the baseline before caudal block. Thus, PI provides an earlier, more objective, and more sensitive indicator to assess the early onset of caudal block under basal ketamine anesthesia.

The effect of ketamine on optical and electrical characteristics of spreading depolarizations in gyrencephalic swine cortex.

PubMed

Sánchez-Porras, Renán; Santos, Edgar; Schöll, Michael; Stock, Christian; Zheng, Zelong; Schiebel, Patrick; Orakcioglu, Berk; Unterberg, Andreas W; Sakowitz, Oliver W

2014-09-01

Spreading depolarization (SD) is a wave of mass neuronal and glial depolarization that propagates across the cerebral cortex and has been implicated in the pathophysiology of brain injury states and migraine with aura. Analgesics and sedatives seem to have a significant effect on SD modulation. Studies have shown that ketamine, an NMDA receptor blocker, has the capacity to influence SD occurrence. The aim of this study was to analyze the dose-dependent effect of ketamine on SD susceptibility through electrocorticography (ECoG) and intrinsic optical signal (IOS) imaging in a gyrencephalic brain. Ketamine in a low-dose infusion (2 mg/kg/h) decreases SD spread and had an effect on the amplitude of SD deflections, as well as on duration, and speed. Moreover, during ketamine infusion at this dose, there was a sustained decrease in the hyperemic response following SD. However, a high-dose infusion (4 mg/kg/h) of ketamine inhibited SD induction and expansion. Furthermore, a high-dose bolus (4 mg/kg), 1 min after stimulation, blocked SD propagation abruptly within 1-2 min, and hindered SD induction and expansion for the following 15-30 min. The results suggest that ketamine may be therapeutically beneficial in preventing SDs. Nonetheless, an adequate dosage and way of administration should be considered and established for human use. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of ketamine and lidocaine in combination on the sevoflurane minimum alveolar concentration in alpacas

PubMed Central

Queiroz-Williams, Patricia; Doherty, Thomas J.; da Cunha, Anderson F.; Leonardi, Claudia

2016-01-01

This study investigated the effects of ketamine and lidocaine in combination on the minimum alveolar concentration of sevoflurane (MACSEVO) in alpacas. Eight healthy, intact male, adult alpacas were studied on 2 separate occasions. Anesthesia was induced with SEVO, and baseline MAC (MACB) determination began 45 min after induction. After MACB determination, alpacas were randomly given either an intravenous (IV) loading dose (LD) and infusion of saline or a loading dose [ketamine = 0.5 mg/kg body weight (BW); lidocaine = 2 mg/kg BW] and an infusion of ketamine (25 μg/kg BW per minute) in combination with lidocaine (50 μg/kg BW per minute), and MACSEVO was re-determined (MACT). Quality of recovery, time-to-extubation, and time-to-standing, were also evaluated. Mean MACB was 1.88% ± 0.13% and 1.89% ± 0.14% for the saline and ketamine + lidocaine groups, respectively. Ketamine and lidocaine administration decreased (P < 0.05) MACB by 57% and mean MACT was 0.83% ± 0.10%. Saline administration did not change MACB. Time to determine MACB and MACT was not significantly different between the treatments. The quality of recovery, time-to-extubation, and time-to-standing, were not different between groups. The infusion of ketamine combined with lidocaine significantly decreased MACSEVO by 57% and did not adversely affect time-to-standing or quality of recovery. PMID:27127341

Effects of ketamine and lidocaine in combination on the sevoflurane minimum alveolar concentration in alpacas.

PubMed

Queiroz-Williams, Patricia; Doherty, Thomas J; da Cunha, Anderson F; Leonardi, Claudia

2016-04-01

This study investigated the effects of ketamine and lidocaine in combination on the minimum alveolar concentration of sevoflurane (MACSEVO) in alpacas. Eight healthy, intact male, adult alpacas were studied on 2 separate occasions. Anesthesia was induced with SEVO, and baseline MAC (MACB) determination began 45 min after induction. After MACB determination, alpacas were randomly given either an intravenous (IV) loading dose (LD) and infusion of saline or a loading dose [ketamine = 0.5 mg/kg body weight (BW); lidocaine = 2 mg/kg BW] and an infusion of ketamine (25 μg/kg BW per minute) in combination with lidocaine (50 μg/kg BW per minute), and MACSEVO was re-determined (MACT). Quality of recovery, time-to-extubation, and time-to-standing, were also evaluated. Mean MACB was 1.88% ± 0.13% and 1.89% ± 0.14% for the saline and ketamine + lidocaine groups, respectively. Ketamine and lidocaine administration decreased (P < 0.05) MACB by 57% and mean MACT was 0.83% ± 0.10%. Saline administration did not change MACB. Time to determine MACB and MACT was not significantly different between the treatments. The quality of recovery, time-to-extubation, and time-to-standing, were not different between groups. The infusion of ketamine combined with lidocaine significantly decreased MACSEVO by 57% and did not adversely affect time-to-standing or quality of recovery.

Hedonic sensitivity to low-dose ketamine is modulated by gonadal hormones in a sex-dependent manner

PubMed Central

Saland, Samantha K.; Schoepfer, Kristin J.; Kabbaj, Mohamed

2016-01-01

We recently reported a greater sensitivity of female rats to rapid antidepressant-like effects of ketamine compared to male rats, and that ovarian-derived estradiol (E2) and progesterone (P4) are essential for this response. However, to what extent testosterone may also contribute, and whether duration of response to ketamine is modulated in a sex- and hormone-dependent manner remains unclear. To explore this, we systematically investigated the influence of testosterone, estradiol and progesterone on initiation and maintenance of hedonic response to low-dose ketamine (2.5 mg/kg) in intact and gonadectomized male and female rats. Ketamine induced a sustained increase in sucrose preference of female, but not male, rats in an E2P4-dependent manner. Whereas testosterone failed to alter male treatment response, concurrent administration of P4 alone in intact males enhanced hedonic response low-dose ketamine. Treatment responsiveness in female rats only was associated with greater hippocampal BDNF levels, but not activation of key downstream signaling effectors. We provide novel evidence supporting activational roles for ovarian-, but not testicular-, derived hormones in mediating hedonic sensitivity to low-dose ketamine in female and male rats, respectively. Organizational differences may, in part, account for the persistence of sex differences following gonadectomy and selective involvement of BDNF in treatment response. PMID:26888470

Pharmacokinetics of ketamine and its metabolite norketamine administered at a sub-anesthetic dose together with xylazine to calves prior to castration.

PubMed

Gehring, R; Coetzee, J F; Tarus-Sang, J; Apley, M D

2009-04-01

The objective of this study was to evaluate the plasma pharmacokinetics of ketamine and its active metabolite norketamine administered intravenously at a dose of 0.1 mg/kg together with xylazine (0.05 mg/kg) to control the pain associated with castration in calves. A two-compartment model with an additional metabolite compartment linked to the central compartment was used to simultaneously describe the time-concentration profiles of both ketamine and its major metabolite norketamine. Parameter values estimated from the time-concentration profiles observed in this study were volume of the central compartment (V(c) = 132.82 +/- 68.23 mL/kg), distribution clearance (CL(D) = 15.49 +/- 2.56 mL/min/kg), volume of the peripheral compartment (V(T) = 257.05 +/- 41.65 mL/kg), ketamine clearance by the formation of the norketamine metabolite (CL(2M) = 8.56 +/- 7.37 mL/kg/min) and ketamine clearance by other routes (CL(o) = 16.41 +/- 3.42 mL/kg/min). Previously published data from rats suggest that the metabolite norketamine contributes to the analgesic effect of ketamine, with a potency that is one-third of the parent drug. An understanding of the time-concentration relationships and the disposition of the parent drug and its metabolite is therefore important for a better understanding of the analgesic potential of ketamine in cattle.

Small Dose Ketamine Improves Postoperative Analgesia and Rehabilitation After Total Knee Arthroplasty.

PubMed Central

Chauvin, Marcel; Manoir, Bertrand Du; Langlois, Mathieu; Sessler, Daniel I.; Fletcher, Dominique

2005-01-01

We designed this study to evaluate the effect of small-dose intravenous ketamine in combination with continuous femoral nerve block on postoperative pain and rehabilitation after total knee arthroplasty. Continuous femoral nerve block with ropivacaine was started before surgery and continued in the surgical ward for 48 h. Patients were randomly assigned to receive an initial bolus of 0.5 mg/kg ketamine followed by a continuous infusion of 3 μg·kg-1·min-1 during surgery and 1.5 μg·kg-1·min-1 for 48 h (Ketamine group) or an equal volume of saline (Control group). Additional postoperative analgesia was provided by patient-controlled intravenous morphine. Pain scores and morphine consumption were recorded over 48 hours. The maximal degree of active knee flexion tolerated was recorded daily until hospital discharge. Follow up was performed 6 weeks and 3 months after surgery. The Ketamine group required significantly less morphine than the Control group (45 ± 20 mg versus 69 ± 30 mg; P < 0.02). Patients in the Ketamine group reached 90° of active knee flexion more rapidly than those in the Control group (P < 0.02). Outcomes at 6 weeks and 3 months were similar in each group. These results confirm that ketamine is a useful analgesic adjuvant in perioperative multimodal analgesia with a positive impact on early knee mobilization. PMID:15673878

Ketamine as a Rapid Treatment for Post-Traumatic Stress Disorder

DTIC Science & Technology

2011-10-01

Post - traumatic stress disorder ( PTSD ) is a debilitating anxiety disorder characterized by intrusive re-experiences of the traumatic events...08-1-0602 TITLE: Ketamine as a Rapid Treatment for Post - Traumatic Stress Disorder PRINCIPAL INVESTIGATOR: Dennis Charney...dissociative effects of ketamine but not have any sustained anxiolytic and antidepressant effects. Forty individuals diagnosed with post - traumatic

Impact comparison of ketamine and sodium thiopental on anesthesia during electroconvulsive therapy in major depression patients with drug-resistant; a double-blind randomized clinical trial.

PubMed

Salehi, B; Mohammadbeigi, A; Kamali, A R; Taheri-Nejad, M R; Moshiri, I

2015-01-01

Electroconvulsive therapy (ECT) is one of the available and the most effective therapies for the treatment of resistant depression. Considering the crucial role of seizure duration on therapeutic response in patients treated with ECT, this study aimed to compare the effect of ketamine and sodium thiopental anesthesia during ECT for treatment of patients with drug-resistant major depression (DRMD). In a double-blind randomized clinical trial, 160 patients with DRMD were selected consequently and were assigned randomly into two groups including ketamine 0.8 mg/kg and sodium thiopental 1.5 mg/kg. The seizure duration, recovery time, and the side effects of anesthesia were evaluated after 1-h after anesthesia. Data of recovery time and complication collected in 2 nd , 4 th , 6 th , and 8 th ECT. Depression was assessed by Hamilton depression scale. The results indicated that ketamine and sodium thiopental had a significant effect on the reduction of depression scores in patients with DRMD (P < 0.05). Complications such as a headache, nausea, pain at the injection site, short-term delirium, and long-term delirium were higher in ketamine group (P > 0.05). But ketamine was more effective in improvement of depression score and increasing systolic and diastolic blood pressure (P < 0.05). The mean of seizure duration showed a decreasing trend and was significant between two study groups (P < 0.05). Anesthesia induced by ketamine during ECT therapy increased blood pressure and seizure duration. Therefore, due to lower medical complication and attack rate of seizure, ketamine is an appropriate option for anesthesia with ECT in patients with DRMD.

Impact comparison of ketamine and sodium thiopental on anesthesia during electroconvulsive therapy in major depression patients with drug-resistant; a double-blind randomized clinical trial

PubMed Central

Salehi, B.; Mohammadbeigi, A.; Kamali, A. R.; Taheri-Nejad, M. R.; Moshiri, I.

2015-01-01

Background: Electroconvulsive therapy (ECT) is one of the available and the most effective therapies for the treatment of resistant depression. Considering the crucial role of seizure duration on therapeutic response in patients treated with ECT, this study aimed to compare the effect of ketamine and sodium thiopental anesthesia during ECT for treatment of patients with drug-resistant major depression (DRMD). Materials and Methods: In a double-blind randomized clinical trial, 160 patients with DRMD were selected consequently and were assigned randomly into two groups including ketamine 0.8 mg/kg and sodium thiopental 1.5 mg/kg. The seizure duration, recovery time, and the side effects of anesthesia were evaluated after 1-h after anesthesia. Data of recovery time and complication collected in 2nd, 4th, 6th, and 8th ECT. Depression was assessed by Hamilton depression scale. Results: The results indicated that ketamine and sodium thiopental had a significant effect on the reduction of depression scores in patients with DRMD (P < 0.05). Complications such as a headache, nausea, pain at the injection site, short-term delirium, and long-term delirium were higher in ketamine group (P > 0.05). But ketamine was more effective in improvement of depression score and increasing systolic and diastolic blood pressure (P < 0.05). The mean of seizure duration showed a decreasing trend and was significant between two study groups (P < 0.05). Conclusion: Anesthesia induced by ketamine during ECT therapy increased blood pressure and seizure duration. Therefore, due to lower medical complication and attack rate of seizure, ketamine is an appropriate option for anesthesia with ECT in patients with DRMD. PMID:26440233

Distinct retrosplenial cortex cell populations and their spike dynamics during ketamine-induced unconscious state

PubMed Central

Zhao, Fang; Tsien, Joe Z.

2017-01-01

Ketamine is known to induce psychotic-like symptoms, including delirium and visual hallucinations. It also causes neuronal damage and cell death in the retrosplenial cortex (RSC), an area that is thought to be a part of high visual cortical pathways and at least partially responsible for ketamine’s psychotomimetic activities. However, the basic physiological properties of RSC cells as well as their response to ketamine in vivo remained largely unexplored. Here, we combine a computational method, the Inter-Spike Interval Classification Analysis (ISICA), and in vivo recordings to uncover and profile excitatory cell subtypes within layers 2&3 and 5&6 of the RSC in mice within both conscious, sleep, and ketamine-induced unconscious states. We demonstrate two distinct excitatory principal cell sub-populations, namely, high-bursting excitatory principal cells and low-bursting excitatory principal cells, within layers 2&3, and show that this classification is robust over the conscious states, namely quiet awake, and natural unconscious sleep periods. Similarly, we provide evidence of high-bursting and low-bursting excitatory principal cell sub-populations within layers 5&6 that remained distinct during quiet awake and sleep states. We further examined how these subtypes are dynamically altered by ketamine. During ketamine-induced unconscious state, these distinct excitatory principal cell subtypes in both layer 2&3 and layer 5&6 exhibited distinct dynamics. We also uncovered different dynamics of local field potential under various brain states in layer 2&3 and layer 5&6. Interestingly, ketamine administration induced high gamma oscillations in layer 2&3 of the RSC, but not layer 5&6. Our results show that excitatory principal cells within RSC layers 2&3 and 5&6 contain multiple physiologically distinct sub-populations, and they are differentially affected by ketamine. PMID:29073221

Ketamine as an Analgesic Adjuvant in Adult Trauma Intensive Care Unit Patients With Rib Fracture.

PubMed

Walters, Mary K; Farhat, Joseph; Bischoff, James; Foss, Mary; Evans, Cory

2018-03-01

Rib fracture associated pain is difficult to control. There are no published studies that use ketamine as a therapeutic modality to reduce the amount of opioid to control rib fracture pain. To examine the analgesic effects of adjuvant ketamine on pain scale scores in trauma intensive care unit (ICU) rib fracture. This retrospective, case-control cohort chart review evaluated ICU adult patients with a diagnosis of ≥1 rib fracture and an Injury Severity Score >15 during 2016. Patients received standard-of-care pain management with the physician's choice analgesics with or without ketamine as a continuous, fixed, intravenous infusion at 0.1 mg/kg/h. A total of 15 ketamine treatment patients were matched with 15 control standard-of-care patients. Efficacy was measured via Numeric Pain Scale (NPS)/Behavioral Pain Scale (BPS) scores, opioid use, and ICU and hospital length of stay. Safety of ketamine was measured by changes in vital signs, adverse effects, and mortality. Average NPS/BPS, severest NPS/BPS, and opioid use were lower in the ketamine group than in controls (NPS: 4.1 vs 5.8, P < 0.001; severest NPS: 7.0 vs 8.9, P = 0.004; opioid use: 2.5 vs 3.5 mg morphine equivalents/h/d, P = 0.015). No difference was found between the cohort's length of stay or mortality. Average diastolic blood pressure was higher in the treatment group versus the control group (75.3 vs 64.6 mm Hg, P = 0.014). Low-dose ketamine appears to be a safe and effective adjuvant option to reduce pain and decrease opioid use in rib fracture.

Ketamine-induced apoptosis in the mouse cerebral cortex follows similar characteristic of physiological apoptosis and can be regulated by neuronal activity.

PubMed

Wang, Qi; Shen, Feng-Yan; Zou, Rong; Zheng, Jing-Jing; Yu, Xiang; Wang, Ying-Wei

2017-06-17

The effects of general anesthetics on inducing neuronal apoptosis during early brain development are well-documented. However, since physiological apoptosis also occurs during this developmental window, it is important to determine whether anesthesia-induced apoptosis targets the same cell population as physiological apoptosis or different cell types altogether. To provide an adequate plane of surgery, ketamine was co-administered with dexmedetomidine. The apoptotic neurons in the mouse primary somatosensory cortex (S1) were quantitated by immunohistochemistry. To explore the effect of neural activity on ketamine-induced apoptosis, the approaches of Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) and an environmental enrichment (EE) were performed. Ketamine-induced apoptosis in S1 is most prominent at postnatal days 5 and 7 (P5 - P7), and becomes insignificant by P12. Physiological and ketamine-induced apoptosis follow similar developmental patterns, mostly comprised of layer V pyramidal neurons at P5 and shifting to mostly layer II to IV GABAergic neurons by P9. Changes in neuronal activity induced by the DREADD system bidirectionally regulated the pattern of ketamine-induced apoptosis, with reduced activity inducing increased apoptosis and shifting the lamination pattern to a more immature form. Importantly, rearing mice in an EE significantly reduced the magnitude of ketamine-induced apoptosis and shifted its developmental pattern to a more mature form. Together, these results demonstrate that lamination pattern and cell-type dependent vulnerability to ketamine-induced apoptosis follow the physiological apoptosis pattern and are age- and activity-dependent. Naturally elevating neuronal activity is a possible method for reducing the adverse effects of general anesthesia.

Relationship between ketamine-induced developmental neurotoxicity and NMDA receptor-mediated calcium influx in neural stem cell-derived neurons.

PubMed

Wang, Cheng; Liu, Fang; Patterson, Tucker A; Paule, Merle G; Slikker, William

2017-05-01

Ketamine, a noncompetitive NMDA receptor antagonist, is used as a general anesthetic and recent data suggest that general anesthetics can cause neuronal damage when exposure occurs during early brain development. To elucidate the underlying mechanisms associated with ketamine-induced neurotoxicity, stem cell-derived models, such as rodent neural stem cells harvested from rat fetuses and/or neural stem cells derived from human induced pluripotent stem cells (iPSC) can be utilized. Prolonged exposure of rodent neural stem cells to clinically-relevant concentrations of ketamine resulted in elevated NMDA receptor levels as indicated by NR1subunit over-expression in neurons. This was associated with enhanced damage in neurons. In contrast, the viability and proliferation rate of undifferentiated neural stem cells were not significantly affected after ketamine exposure. Calcium imaging data indicated that 50μM NMDA did not cause a significant influx of calcium in typical undifferentiated neural stem cells; however, it did produce an immediate elevation of intracellular free Ca 2+ [Ca 2+ ] i in differentiated neurons derived from the same neural stem cells. This paper reviews the literature on this subject and previous findings suggest that prolonged exposure of developing neurons to ketamine produces an increase in NMDA receptor expression (compensatory up-regulation) which allows for a higher/toxic influx of calcium into neurons once ketamine is removed from the system, leading to neuronal cell death likely due to elevated reactive oxygen species generation. The absence of functional NMDA receptors in cultured neural stem cells likely explains why clinically-relevant concentrations of ketamine did not affect undifferentiated neural stem cell viability. Published by Elsevier B.V.

Adverse Events During a Randomized Trial of Ketamine Versus Co-Administration of Ketamine and Propofol for Procedural Sedation in a Pediatric Emergency Department.

PubMed

Weisz, Keith; Bajaj, Lalit; Deakyne, Sara J; Brou, Lina; Brent, Alison; Wathen, Joseph; Roosevelt, Genie E

2017-07-01

The co-administration of ketamine and propofol (CoKP) is thought to maximize the beneficial profile of each medication, while minimizing the respective adverse effects of each medication. Our objective was to compare adverse events between ketamine monotherapy (KM) and CoKP for procedural sedation and analgesia (PSA) in a pediatric emergency department (ED). This was a prospective, randomized, single-blinded, controlled trial of KM vs. CoKP in patients between 3 and 21 years of age. The attending physician administered either ketamine 1 mg/kg i.v. or ketamine 0.5 mg/kg and propofol 0.5 mg/kg i.v. The physician could administer up to three additional doses of ketamine (0.5 mg/kg/dose) or ketamine/propofol (0.25 mg/kg/dose of each). Adverse events (e.g., respiratory events, cardiovascular events, unpleasant emergence reactions) were recorded. Secondary outcomes included efficacy, recovery time, and satisfaction scores. Ninety-six patients were randomized to KM and 87 patients were randomized to CoKP. There was no difference in adverse events or type of adverse event, except nausea was more common in the KM group. Efficacy of PSA was higher in the KM group (99%) compared to the CoKP group (90%). Median recovery time was the same. Satisfaction scores by providers, including nurses, were higher for KM, although parents were equally satisfied with both sedation regimens. We found no significant differences in adverse events between the KM and CoKP groups. While CoKP is a reasonable choice for pediatric PSA, our study did not demonstrate an advantage of this combination over KM. Copyright © 2017 Elsevier Inc. All rights reserved.

Intraoperative ketamine reduces immediate postoperative opioid consumption after spinal fusion surgery in chronic pain patients with opioid dependency: a randomized, blinded trial.

PubMed

Nielsen, Rikke Vibeke; Fomsgaard, Jonna Storm; Siegel, Hanna; Martusevicius, Robertas; Nikolajsen, Lone; Dahl, Jørgen Berg; Mathiesen, Ole

2017-03-01

Perioperative handling of surgical patients with opioid dependency represents an important clinical problem. Animal studies suggest that ketamine attenuates central sensitization and hyperalgesia and thereby reduces postoperative opioid tolerance. We hypothesized that intraoperative ketamine would reduce immediate postoperative opioid consumption compared with placebo in chronic pain patients with opioid dependency undergoing lumbar spinal fusion surgery. Primary outcome was morphine consumption 0 to 24 hours postoperatively. Secondary outcomes were acute pain at rest and during mobilization 2 to 24 hours postoperatively (visual analogue scale), adverse events, and persistent pain 6 months postoperatively. One hundred fifty patients were randomly assigned to intraoperative S-ketamine bolus 0.5 mg/kg and infusion 0.25 mg·kg·h or placebo. Postoperatively, patients received their usual opioids, paracetamol and IV patient-controlled analgesia with morphine. In the final analyses, 147 patients were included. Patient-controlled analgesia IV morphine consumption 0 to 24 hours postoperatively was significantly reduced in the ketamine group compared with the placebo group: 79 (47) vs 121 (53) mg IV, mean difference 42 mg (95% confidence interval -59 to -25), P < 0.001. Sedation was significantly reduced in the ketamine group 6 and 24 hours postoperatively. There were no significant differences regarding acute pain, nausea, vomiting, hallucinations, or nightmares. Back pain at 6 months postoperatively compared with preoperative pain was significantly more improved in the ketamine group compared with the placebo group, P = 0.005. In conclusion, intraoperative ketamine significantly reduced morphine consumption 0 to 24 hours after lumbar fusion surgery in opioid-dependent patients. The trend regarding less persistent pain 6 months postoperatively needs further investigation.

Efficacy of ketamine hydrochloride administered as a basilar sesamoid nerve block in alleviating foot pain in horses caused by natural disease.

PubMed

Schumacher, J; DeGraves, F; Cesar, F; Duran, S

2014-09-01

A local anaesthetic agent capable of temporarily resolving lameness after being administered perineurally would be helpful because rapid return of lameness would allow for other analgesic techniques to be performed within a short period of time. To determine if a 3% solution of ketamine hydrochloride (HCl), administered around the palmar nerves at the level of the base of the proximal sesamoid bones, can improve naturally occurring lameness that can be improved or abolished with a basilar sesamoid nerve block performed using lidocaine HCl and to compare the change in gait produced using lidocaine to the change in gait produced using ketamine by using objective lameness assessment. Experimental trial using research horses with naturally occurring lameness. Seven horses, chronically lame on a thoracic limb, were chosen for the study. A wireless, inertial, sensor-based, motion analysis system was used to evaluate lameness before and after administration of 2% lidocaine and later, before and after administration of 3% ketamine over the palmar digital nerves at the base of the proximal sesamoid bones (a basilar sesamoid nerve block) at 5 min intervals for 30 min. Lameness scores obtained before and after administration of lidocaine and ketamine HCl were compared using repeated measures analysis. Gait significantly improved after basilar sesamoid nerve blocks using 2% lidocaine, but gait did not significantly improve after performing the same nerve block using 3% ketamine HCl. Ketamine (3%) administered perineurally for regional anaesthesia of the digit does not desensitise the digit to the same extent as does lidocaine and thus 3% ketamine appears to have no value as a local anaesthetic agent for diagnostic regional anaesthesia. © 2013 EVJ Ltd.

Perioperative epidural or intravenous ketamine does not improve the effectiveness of thoracic epidural analgesia for acute and chronic pain after thoracotomy.

PubMed

Tena, Beatriz; Gomar, Carmen; Rios, Jose

2014-06-01

Persistent postsurgical pain (PPP) after thoracotomy effect 50% to 80%. Nerve damage and central sensitization involving NDMDAr activation may play an important role. This study evaluates the efficacy of adding intravenous (IV) or epidural ketamine to thoracic epidural analgesia (TEA) after thoracotomy. Double-blind randomized study on patients undergoing thoracotomy allocated to one of the following: group Kiv (IV racemic ketamine 0.5 mg/kg preincisional +0.25 mg/kg/h for 48 h), group Kep (epidural racemic ketamine 0.5 mg/kg preincisional +0.25 mg/kg/h for 48 h), or group S (saline). Postoperative analgesia was ensured by TEA with ropivacaine and fentanyl. Pain visual analog scales (VAS), Neuropathic Pain Symptom Inventory, Catastrophizing Scale, and Quantitative Sensory Testing, measuring both the peri-incisional and distant hyperalgesia area, were conducted preoperatively and postoperatively until 6 months. Plasma ketamine levels and stability of the analgesic solutions were analyzed. A total of 104 patients were included. PPP incidence was 20% at 6 months. Pain scores on coughing were significantly lower in Kiv and Kep than in S at 24 and 72 hours, but there were no differences afterwards. There were no significant differences in pain at rest, Neuropathic Pain Symptom Inventory, and Catastrophizing Scale, or in the area of mechanical allodynia at any time. Adverse effects were mild. Plasma ketamine levels did not differ significantly between groups. Analgesic solutions were stable. Adding epidural or IV racemic ketamine to TEA after thoracotomy did not lead to any reduction in PPP or allodynia. Epidural administration produced similar plasma ketamine levels to the IV route.

Ketamine added to morphine or hydromorphone patient-controlled analgesia for acute postoperative pain in adults: a systematic review and meta-analysis of randomized trials.

PubMed

Wang, Li; Johnston, Bradley; Kaushal, Alka; Cheng, Davy; Zhu, Fang; Martin, Janet

2016-03-01

To determine whether ketamine added to morphine or hydromorphone patient-controlled analgesia (PCA) provides clinically relevant reductions in postoperative pain, opioid requirements, and adverse events when compared with morphine or hydromorphone PCA in adults undergoing surgery. We systematically searched six databases up to June 2, 2015 for randomized controlled trials (RCTs) comparing ketamine plus morphine/hydromorphone PCA vs morphine/hydromorphone PCA for postoperative pain in adults. Thirty-six RCTs including 2,502 patients proved eligible, and 22 of these were at low risk of bias. The addition of ketamine to morphine/hydromorphone PCA decreased postoperative pain intensity at six to 72 hr when measured at rest (weighted mean difference [WMD] on a 10-cm visual analogue scale ranged from -0.4 to -1.3 cm) and during mobilization (WMD ranged from -0.4 to -0.5 cm). Adjunctive ketamine also significantly reduced cumulative morphine consumption at 24-72 hr by approximately 5-20 mg. Predefined subgroup analyses and meta-regression did not detect significant differences across subgroups, including a dose-response relationship. There was no significant difference in patient satisfaction scores at 24 and 48 hr. Nevertheless, the addition of ketamine to morphine/hydromorphone PCA significantly reduced postoperative nausea and vomiting (relative risk, 0.71; 95% confidence interval [CI], 0.60 to 0.85; absolute risk reduction, 8.9%; 95% CI, 4.6 to 12.2). Significant effects on other adverse events (e.g., hallucinations, vivid dreams) were not detected, though only a few studies reported on them. Adding ketamine to morphine/hydromorphone PCA provides a small improvement in postoperative analgesia while reducing opioid requirements. Adjunctive ketamine also reduces postoperative nausea and vomiting without a detected increase in other adverse effects; however, adverse events were probably underreported.

Can gradual dose titration of ketamine for management of neuropathic pain prevent psychotomimetic effects in patients with advanced cancer?

PubMed

Okamoto, Yoshiaki; Tsuneto, Satoru; Tanimukai, Hitoshi; Matsuda, Yoichi; Ohno, Yumiko; Tsugane, Mamiko; Uejima, Etsuko

2013-08-01

Ketamine is often used to manage neuropathic pain in patients with cancer. However, it occasionally causes psychotomimetic effects such as vivid dreams, nightmares, illusions, hallucinations, and altered body image. To examine whether gradual dose titration of ketamine for management of neuropathic pain prevents psychotomimetic effects in patients with advanced cancer. This was a retrospective chart review. We administered ketamine when neuropathic pain in patients with advanced cancer became refractory to opioids and oral adjuvant analgesics. The starting dose of ketamine was 10 mg/d by continuous intravenous infusion. The dose was gradually increased by 10 mg/d every 4 to 6 hours to 50 mg/d or until the pain was relieved. It was subsequently increased by 25 mg/d every 12 to 24 hours until the pain was relieved. For this study, we enrolled 46 patients with advanced cancer. The mean age was 52.2 ± 16.9 years. The mean dose at onset of action and maximum dose of ketamine were 56 ± 58 and 272 ± 214 mg/d, respectively. The mean pain intensity (numerical rating scale) decreased significantly from 7.3 ± 2.0 to 3.5 ± 2.2 after the administration of ketamine (P < .01). The effectiveness was 69.5%. No psychotomimetic effect of less than 300 mg/d was observed during the introduction phase even though psychotropic drugs were not prescribed. Mild sedation was observed in 3 patients (7%) as the only adverse effect during the introduction phase. Gradual dose titration of ketamine for management of neuropathic pain can prevent psychotomimetic effects in patients with advanced cancer.

A Single Sub-anesthetic Dose of Ketamine Relieves Depression-like Behaviors Induced by Neuropathic Pain in Rats

PubMed Central

Wang, Jing; Goffer, Yossef; Xu, Duo; Tukey, David S.; Shamir, D. B.; Eberle, Sarah E.; Zou, Anthony H.; Blanck, Thomas J.J.; Ziff, Edward B.

2011-01-01

Background Chronic pain is associated with depression. In rodents, pain is often assessed by sensory hypersensitivity, which does not sufficiently measure affective responses. Low-dose ketamine has been used to treat both pain and depression, but it is not clear whether ketamine can relieve depression associated with chronic pain and whether this antidepressant effect depends on its anti-nociceptive properties. Methods We examined whether the spared nerve injury (SNI) model of neuropathic pain induces depressive behavior in rats, using sucrose preference test and forced swim test, and tested whether a subanesthetic dose of ketamine treats SNI-induced depression. Results SNI-treated rats, compared with control, showed decreased sucrose preference (0.719 ± 0.068 (mean ± SEM) vs. 0.946 ± 0.010) and enhanced immobility in the forced swim test (107.3 ± 14.6s vs. 56.2 ± 12.5s). Further, sham-operated rats demonstrated depressive behaviors in the acute postoperative period (0.790 ± 0.062 on postoperative day 2). A single subanesthetic dose of ketamine (10mg/kg) did not alter SNI-induced hypersensitivity; however, it treated SNI-associated depression-like behaviors (0.896 ± 0.020 for ketamine vs. 0.663 ± 0.080 for control 1 day after administration; 0.858 ± 0.017 for ketamine vs. 0.683 ± 0.077 for control 5 days after administration). Conclusions Chronic neuropathic pain leads to depression-like behaviors. The postoperative period also confers vulnerability to depression, possibly due to acute pain. Sucrose preference test and forced swim test may be used to compliment sensory tests for assessment of pain in animal studies. Low-dose ketamine can treat depression-like behaviors induced by chronic neuropathic pain. PMID:21934410

Opposite effects of ketamine and deep brain stimulation on rat thalamocortical information processing.

PubMed

Kulikova, Sofya P; Tolmacheva, Elena A; Anderson, Paul; Gaudias, Julien; Adams, Brendan E; Zheng, Thomas; Pinault, Didier

2012-11-01

Sensory and cognitive deficits are common in schizophrenia. They are associated with abnormal brain rhythms, including disturbances in γ frequency (30-80 Hz) oscillations (GFO) in cortex-related networks. However, the underlying anatomofunctional mechanisms remain elusive. Clinical and experimental evidence suggests that these deficits result from a hyporegulation of glutamate N-methyl-D-aspartate receptors. Here we modeled these deficits in rats with ketamine, a non-competitive N-methyl-D-aspartate receptor antagonist and a translational psychotomimetic substance at subanesthetic doses. We tested the hypothesis that ketamine-induced sensory deficits involve an impairment of the ability of the thalamocortical (TC) system to discriminate the relevant information from the baseline activity. Furthermore, we wanted to assess whether ketamine disrupts synaptic plasticity in TC systems. We conducted multisite network recordings in the rat somatosensory TC system, natural stimulation of the vibrissae and high-frequency electrical stimulation (HFS) of the thalamus. A single systemic injection of ketamine increased the amount of baseline GFO, reduced the amplitude of the sensory-evoked TC response and decreased the power of the sensory-evoked GFO. Furthermore, cortical application of ketamine elicited local and distant increases in baseline GFO. The ketamine effects were transient. Unexpectedly, HFS of the TC pathway had opposite actions. In conclusion, ketamine and thalamic HFS have opposite effects on the ability of the somatosensory TC system to discriminate the sensory-evoked response from the baseline GFO during information processing. Investigating the link between the state and function of the TC system may conceptually be a key strategy to design innovative therapies against neuropsychiatric disorders. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Clonidine versus ketamine to prevent tourniquet pain during intravenous regional anesthesia with lidocaine.

PubMed

Gorgias, N K; Maidatsi, P G; Kyriakidis, A M; Karakoulas, K A; Alvanos, D N; Giala, M M

2001-01-01

Both clonidine and ketamine have been found to prolong the action of local anesthetics through a peripheral mechanism. Our study compares the efficacy of a low dose of clonidine or ketamine separately added to intravenous regional anesthesia (IVRA) with lidocaine to prevent tourniquet pain. We conducted a prospective randomized double-blinded study in 45 patients undergoing hand or forearm surgery, with anticipated duration exceeding 1 hour under IVRA. Proximal cuff inflation of a double tourniquet was followed by administration of 40 mL of lidocaine 0.5% and either saline, 1 microg/kg clonidine, or 0.1 mg/kg ketamine. When anesthesia was established, the inflation of the proximal and distal cuff was interchanged. Thereafter, tourniquet pain was rated on a visual analog scale (VAS) every 10 minutes. Intraoperatively, boluses of 25 microg fentanyl were provided for tourniquet pain treatment when required, and total fentanyl consumption was recorded. Patients receiving plain lidocaine persistently reported the highest pain scores among groups (P <.001) 20 minutes after distal cuff inflation. Differences between the groups with additional treatment were noted 50 minutes after distal cuff inflation and until the end of the observation, with significantly lower VAS ratings (P <.001 to P <.01) in ketamine-treated patients. Total fentanyl consumption was significantly decreased by ketamine (70.00 +/- 25.35 microg) or clonidine (136.67 +/- 39.94 microg) compared with the plain lidocaine group (215.33 +/- 52.33 microg) (P <.001 between all groups). The addition of clonidine 1 microg/kg or ketamine 0.1 mg/kg to lidocaine for IVRA delays the onset of unbearable tourniquet pain and decreases analgesic consumption for tourniquet pain relief, although ketamine has a more potent effect.

Efficacy of Ketamine in Pediatric Sedation Dentistry: A Systematic Review.

PubMed

Oh, Samuel; Kingsley, Karl

2018-05-01

Ketamine has been used as a safe and effective sedative to treat adults and children exhibiting high levels of anxiety or fear during dental treatment. Pediatric dentistry often involves patients with high levels of anxiety and fear and possibly few positive dental experiences. Patient management can involve behavioral approaches, as well as the use of sedation or general anesthesia with a variety of agents, including midazolam, diazepam, hydroxyzine, meperidine, and ketamine. The aim of this study was to investigate the clinical efficacy of ketamine use in pediatric sedation dentistry through systematic review and analysis. A systematic review of publications between 1990 and 2015 was conducted using PubMed and MEDLINE databases maintained by the US National Library of Medicine and the National Institutes of Health. The keywords used were (ketamine) AND (dental OR dentistry) AND (sedation). The abstract and title of all potential publications were then screened for clinical trials and to remove non-English articles, non-human or animal trials, and other non-dental or non-relevant studies. A total of 1,657 citations were initially identified, reviewed, and screened, eventually resulting in inclusion of 25 clinical trials in this systematic review. Nineteen studies evaluated ketamine effects in pediatric dental sedation using oral (non-invasive) administration, three involved subcutaneous or intramuscular injection, and three were completed intravenously. Evidence analysis of these trials revealed the majority (n = 22/25) provided strong, positive evidence for the use of ketamine (alone or in combination) to reduce dental anxiety and behavioral non-compliance with the remainder suggesting equivocal results. Additional endpoints evaluated in some studies involved dosage, as well as time to achieve sedation effect. The use of ketamine (alone or in combination) can provide safe, effective, and timely sedation in pediatric patients regardless of the route of administration.

Long-Term Stability of Tramadol and Ketamine Solutions for Patient-Controlled Analgesia Delivery

PubMed Central

Gu, Junfeng; Qin, Wengang; Chen, Fuchao; Xia, Zhongyuan

2015-01-01

Background Subanesthetic doses of ketamine as an adjuvant to tramadol in patient-controlled analgesia (PCA) for postoperative pain have been shown to improve the quality of analgesia. However, there are no such commercially available drug mixtures, and the stability of the combination has rarely been assessed. Material/Methods Admixtures were assessed for periods of up to 14 days at 4°C and 25°C. Three different mixtures of tramadol and ketamine (tramadol 5.0 mg/mL + ketamine 0.5 mg/mL, tramadol 5.0 mg/mL + ketamine 1.0 mg/mL, and tramadol 5.0 mg/mL + ketamine 2.0 mg/mL) were prepared in polyolefin bags by combining these 2 drugs with 0.9% sodium chloride (normal saline [NS]). The chemical stability of the admixtures was evaluated by a validated high-performance liquid chromatography (HPLC) method and by measurement of pH values. Solution appearance and color were assessed by observing the samples against black and white backgrounds. Solutions were considered stable if they maintained 90% of the initial concentration of each drug. Results The percentages of initial concentration of tramadol and ketamine in the various solutions remained above 98% when stored at 4°C or 25°C over the testing period. No changes in color or turbidity were observed in any of the prepared solutions. Throughout this period, pH values remained stable. Conclusions The results indicate that the drug mixtures of tramadol with ketamine in NS for PCA delivery systems were stable for 14 days when stored in polyolefin bags at 4°C or 25°C. PMID:26306476

Prepulse inhibition of the startle reflex and its attentional modulation in the human S-ketamine and N,N-dimethyltryptamine (DMT) models of psychosis.

PubMed

Heekeren, K; Neukirch, A; Daumann, J; Stoll, M; Obradovic, M; Kovar, K-A; Geyer, M A; Gouzoulis-Mayfrank, E

2007-05-01

Patients with schizophrenia exhibit diminished prepulse inhibition (PPI) of the acoustic startle reflex and deficits in the attentional modulation of PPI. Pharmacological challenges with hallucinogens are used as models for psychosis in both humans and animals. Remarkably, in contrast to the findings in schizophrenic patients and in animal hallucinogen models of psychosis, previous studies with healthy volunteers demonstrated increased levels of PPI after administration of low to moderate doses of either the antiglutamatergic hallucinogen ketamine or the serotonergic hallucinogen psilocybin. The aim of the present study was to investigate the influence of moderate and high doses of the serotonergic hallucinogen N,N-dimethyltryptamine (DMT) and the N-methyl-D-aspartate antagonist S-ketamine on PPI and its attentional modulation in humans. Fifteen healthy volunteers were included in a double-blind cross-over study with two doses of DMT and S-ketamine. Effects on PPI and its attentional modulation were investigated. Nine subjects completed both experimental days with the two doses of both drugs. S-ketamine increased PPI in both dosages, whereas DMT had no significant effects on PPI. S-ketamine decreased and DMT tended to decrease startle magnitude. There were no significant effects of either drug on the attentional modulation of PPI. In human experimental hallucinogen psychoses, and even with high, clearly psychotogenic doses of DMT or S-ketamine, healthy subjects failed to exhibit the predicted attenuation of PPI. In contrast, PPI was augmented and the startle magnitude was decreased after S-ketamine. These data point to important differences between human hallucinogen models and both animal hallucinogen models of psychosis and naturally occurring schizophrenia.

Repeated chemical immobilization of a captive greater one-horned rhinoceros (Rhinoceros unicornis), using combinations of etorphine, detomidine, and ketamine.

PubMed

Atkinson, Mark W; Hull, Bruce; Gandolf, A Rae; Blumer, Evan S

2002-06-01

An adult, 23 yr-old, male greater one-horned rhinoceros (Rhinoceros unicornis) was repeatedly immobilized with combinations of etorphine, detomidine, and ketamine to provide medical and surgical care to chronic, bilateral, soft tissue lesions on the hind feet and to collect semen by electroejaculation. The rhinoceros was successfully immobilized on 24 occasions over a 55 mo period at approximately 8-10 wk intervals, 17 times with a combination of etorphine and detomidine (M99-D, i.m.) by projectile dart and seven times with a combination of etorphine, ketamine, and detomidine (M99-K-D, i.m.) by pole syringe. The combination of etorphine, detomidine, and ketamine repeatedly and safely induced prolonged anesthesia, and a suitable drug combination includes 3.5-3.8 mg etorphine, 14 mg detomidine, and 400 mg ketamine (M99-K-D) administered i.m. into the neck.

Sit Down to Float: The Cultural Meaning of Ketamine Use in Hong Kong

PubMed Central

Joe-Laidler, Karen; Hunt, Geoffrey

2009-01-01

From the late 1990s onward, ketamine use among young persons in Hong Kong grew rapidly becoming the drug of choice. This article examines ketamine’s attraction in Hong Kong, and in so doing uncover the cultural meaning of ketamine use. The analysis is organized around the emergence and shifts in meanings and experiences of those who initiate and continue to use ketamine. The data stems from a comparative study of the social setting of club drug use in Hong Kong, San Francisco, and Rotterdam. Here we draw from 100 in-depth interviews to examine the experiences of young persons who have used drugs in dance venues in Hong Kong. Our findings indicate that ketamine has become embedded in a distinctively working class youth dance scene, is accessible in terms of supply and cost, shared among a group of friends, and results in a stimulating yet liberating experience beyond that of ecstasy. PMID:19759834

Mechanisms of ketamine on mice hippocampi shown by gas chromatography-mass spectrometry-based metabolomic analysis.

PubMed

Lian, Bin; Xia, Jinjun; Yang, Xun; Zhou, Chanjuan; Gong, Xue; Gui, Siwen; Mao, Qiang; Wang, Ling; Li, Pengfei; Huang, Cheng; Qi, Xunzhong; Xie, Peng

2018-06-13

In the present study, we used a gas chromatography-mass spectrometry-based metabolomics method to evaluate the effects of ketamine on mice hippocampi. Multivariate statistical analysis and ingenuity pathway analysis were then used to identify and explore the potential mechanisms and biofunction of ketamine. Compared with the control (CON) group, 14 differential metabolites that involved amino acid metabolism, energy metabolism, and oxidative stress metabolism were identified. After combination with 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo[f]quinoxaline-2,3-dione (NBQX) administration, six of the 14 metabolites remained significantly differentially expressed between the ketamine (KET) and KET+NBQX groups, including glycine, alanine, glutamine, aspartic acid, myoinositol, and ascorbate, whereas no difference was found in the levels of the other eight metabolites between the KET and KET+NBQX groups, including phosphate, 4-aminobutyric acid, urea, creatine, L-malic acid, galactinol, inosine, and aminomalonic. Our findings indicate that ketamine exerts antidepressant effects through an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid inhibition-dependent mechanism and a mechanism not affected by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid inhibition. Which provides further insight into the therapeutic mechanisms of ketamine in the hippocampus.

Ketamine Therapy for Treatment-resistant Depression in a Patient with Multiple Sclerosis: A Case Report.

PubMed

Messer, Michael M; Haller, Irina V

2017-01-01

Objective: Depression is a common condition among patients with multiple sclerosis and often becomes resistant to oral antidepressants. We report a patient with multiple sclerosis who developed severe treatment-resistant depression and who was successfully treated with intravenous ketamine over the period of two years. Methods: Ketamine treatment protocol included an initial series of six treatments administered every other day, followed by a maintenance schedule. Ketamine was administered intravenously at 0.5mg/kg of ideal body weight over 40 minutes. Depression symptoms were measured using Beck Depression Index. Results: The patient's Beck Depression Index score prior to initiating ketamine treatment was 38, corresponding to severe depression. Response to treatment, defined as 50-percent reduction in Beck Depression Index score, was observed after five treatments. For this patient, the maintenance schedule ranged from a weekly treatment to one treatment every three weeks. During the two-year observation period, this patient was able to maintain a stable non-depressed mood and had no worsening of her MS symptoms. Conclusion: Ketamine may be an alternative treatment for resistant depression and may have a special use in patients with multiple sclerosis.

Pediatric procedural sedation with ketamine: time to discharge after intramuscular versus intravenous administration.

PubMed

Ramaswamy, Preeti; Babl, Franz E; Deasy, Conor; Sharwood, Lisa N

2009-02-01

Ketamine is an attractive agent for pediatric procedural sedation. There are limited data on time to discharge comparing intramuscular (IM) vs. intravenous (IV) ketamine. The authors set out to determine whether IM or IV ketamine leads to quicker discharge from the emergency department (ED) and how side effect profiles compare. All patients who had received ketamine IM or IV at a tertiary children's hospital ED during the 3-year study period (2004-2007) were identified. Prospective sedation registry data, retrospective medical records, and administrative data were reviewed for drug dosages, use of additional agents, time of drug administration to discharge, total ED time (triage to discharge), and adverse events. A subgroup analysis for patients requiring five or fewer sutures (short suture group) was performed. A total of 229 patients were enrolled (60% male) with median age of 2.8 years (IQR =1.8-4.3 years) and median weight of 15.7 kg (range = 8.7-74 kg). Ketamine was most frequently employed for laceration repair (80%) and foreign body removal (9%). Overall, 48% received ketamine IM and 52% received it IV. In the short-suture subgroup, 52% received ketamine IM, while 48% received it IV. Multivariate linear regression analysis determined time from drug administration to patient discharge as 21 minutes shorter for IV compared with IM administration, adjusted for age and number of additional doses (R(2) = -0.35; 95% CI = -0.5 to -0.19; p < 0.001). Total time in the ED (triage to discharge) comparing IV versus IM administration, adjusting for age and gender and number of additional doses, was not significantly different (p = 0.16). In the short-suture subgroup, time to discharge from administration was also shorter in the IV ketamine group (R(2) = -0.454; 95%CI = -0.66 to -0.25; p < 0.001) but similar for total time in ED (p = 0.16). Overall, adverse events occurred in 35% (95% CI = 27% to 45%) of the IM group and 20% (95% CI = 13% to 28%) of the IV group (p = 0.01). Only one patient required brief bag-mask ventilation. In this institution, time from drug injection to discharge was shorter in the IV compared to IM ketamine group, both overall and for the short-suture group. However, time from triage to discharge was similar.

A parallel chiral-achiral liquid chromatographic method for the determination of the stereoisomers of ketamine and ketamine metabolites in the plasma and urine of patients with complex regional pain syndrome

PubMed Central

Moaddel, Ruin; Venkata, Swarajya Lakshmi Vattem; Tanga, Mary J.; Bupp, James E.; Green, Carol E.; Iyer, Lalitha; Furimsky, Anna; Goldberg, Michael E.; Torjman, Marc C.; Wainer, Irving W.

2010-01-01

A parallel chiral/achiral LC-MS/MS assay has been developed and validated to measure the plasma and urine concentrations of the enantiomers of ketamine, (R)- and (S)-Ket, in Complex Regional Pain Syndrome (CRPS) patients receiving a 5-day continuous infusion of a sub-anesthetic dose of (R,S)-Ket. The method was also validated for the determination of the enantiomers of the Ket metabolites norketamine, (R)-and (S)-norKet and dehydronorketamine, (R)- and (S)-DHNK, as well as the diastereomeric metabolites hydroxynorketamine, (2S,6S)-/(2R,6R)-HNK and two hydroxyketamines, (2S,6S)-HKet and (2S,6R)-Hket. In this method, (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK and the diastereomeric hydroxyl-metabolites were separated and quantified using a C18 stationary phase and the relative enantiomeric concentrations of (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK were determined using an AGP-CSP. The analysis of the results of microsomal incubations of (R)- and (S)-Ket and a plasma and urine sample from a CRPS patient indicated the presence of 10 additional compounds and glucuronides. The data from the analysis of the patient sample also demonstrated that a series of HNK metabolites were the primary metabolites in plasma and (R)- and (S)-DHNK were the major metabolites found in urine. The results suggest that norKet is the initial, but not the primary, metabolite and that downstream norKet metabolites play a role in (R,S)-Ket-related pain relief in CRPS patients. PMID:20875593

A parallel chiral-achiral liquid chromatographic method for the determination of the stereoisomers of ketamine and ketamine metabolites in the plasma and urine of patients with complex regional pain syndrome.

PubMed

Moaddel, Ruin; Venkata, Swarajya Lakshmi Vattem; Tanga, Mary J; Bupp, James E; Green, Carol E; Iyer, Lalitha; Furimsky, Anna; Goldberg, Michael E; Torjman, Marc C; Wainer, Irving W

2010-10-15

A parallel chiral/achiral LC-MS/MS assay has been developed and validated to measure the plasma and urine concentrations of the enantiomers of ketamine, (R)- and (S)-Ket, in complex regional pain syndrome (CRPS) patients receiving a 5-day continuous infusion of a sub-anesthetic dose of (R,S)-Ket. The method was also validated for the determination of the enantiomers of the Ket metabolites norketamine, (R)- and (S)-norKet and dehydronorketamine, (R)- and (S)-DHNK, as well as the diastereomeric metabolites hydroxynorketamine, (2S,6S)-/(2R,6R)-HNK and two hydroxyketamines, (2S,6S)-HKet and (2S,6R)-Hket. In this method, (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK and the diastereomeric hydroxyl-metabolites were separated and quantified using a C(18) stationary phase and the relative enantiomeric concentrations of (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK were determined using an AGP-CSP. The analysis of the results of microsomal incubations of (R)- and (S)-Ket and a plasma and urine sample from a CRPS patient indicated the presence of 10 additional compounds and glucuronides. The data from the analysis of the patient sample also demonstrated that a series of HNK metabolites were the primary metabolites in plasma and (R)- and (S)-DHNK were the major metabolites found in urine. The results suggest that norKet is the initial, but not the primary metabolite and that downstream norKet metabolites play a role in (R,S)-Ket-related pain relief in CRPS patients. Published by Elsevier B.V.

A Novel Compound Analgesic Cream (Ketamine, Pentoxifylline, Clonidine, DMSO) for Complex Regional Pain Syndrome Patients.

PubMed

Russo, Marc A; Santarelli, Danielle M

2016-01-01

Evidence suggests that complex regional pain syndrome (CRPS) is a manifestation of microvascular dysfunction. Topical combinations of α2-adrenergic receptor agonists or nitric oxide donors with phosphodiesterase or phosphatidic acid inhibitors formulated to treat microvascular dysfunction have been shown to reduce allodynia in a rat model of CRPS-I. Driven by these findings, we assessed the outcomes of CRPS patients treated with a compound analgesic cream (CAC) consisting of ketamine 10%, pentoxifylline 6%, clonidine 0.2%, and dimethyl sulfoxide 6% to 10%. An audit was conducted on 13 CRPS patients who trialed the CAC. A detailed report was compiled for each patient which comprised baseline characteristics, including CRPS description, previous treatments, and pain scores (numerical pain rating scale; 0 to 10). Recorded outcomes consisted of pain scores, descriptive outcomes, and concurrent medications/treatments, for which basic analysis was performed to determine the effectiveness of the CAC. Case reports are presented for 3 patients with varying outcomes. Nine patients (69%) reported pain/symptom reduction (4.4 ± 2.1 vs. 6.3 ± 1.9) with use of the CAC. Six patients reported sustained benefits after 2 months of CAC use, and 2 patients reported complete resolution of pain/symptoms: one had early CRPS-I and the other received a partial CRPS diagnosis. An otherwise medication refractory and intolerant patient found partial benefit with the CAC. These results demonstrate promise for this topical combination as a useful treatment in multimodal therapy for patients with CRPS, with the potential to resolve pain/symptoms in early CRPS patients. © 2015 World Institute of Pain.

21 CFR 522.23 - Acepromazine.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... It is used in dogs, cats, and horses as follows: (1) Amount. Dogs: 0.25 to 0.5 mg per pound (/lb) of body weight; Cats: 0.5 to 1.0 mg/lb of body weight; Horses: 2.0 to 4.0 mg per 100 lbs of body weight... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS...

21 CFR 522.23 - Acepromazine.

Code of Federal Regulations, 2010 CFR

2010-04-01

.... It is used in dogs, cats, and horses as follows: (1) Amount. Dogs: 0.25 to 0.5 mg per pound (/lb) of body weight; Cats: 0.5 to 1.0 mg/lb of body weight; Horses: 2.0 to 4.0 mg per 100 lbs of body weight... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS...

Application of carvedilol in a dog with pseudoephedrine toxicosis-induced tachycardia

PubMed Central

Kang, Min-Hee; Park, Hee-Myung

2012-01-01

A 15-year-old Yorkshire terrier dog was presented after ingesting 1 capsule of an over-the-counter cold medication containing pseudoephedrine (120 mg/capsule) and cetirizine (5 mg/capsule). Treatment was initiated with acepromazine and carvedilol. The dog responded well to treatment. This is the first known case report using carvedilol to control pseudoephedrine toxicosis. PMID:23277647

Effect of toxic threat nerve agents on anesthetic requirements of representative pr-anesthetic medicants and inhalant and parenteral general anesthetic in the cat. Annual report, 15 July 1985-14 July 1986

DOE Office of Scientific and Technical Information (OSTI.GOV)

Webb, A.I.

1986-07-30

The effect of soman on anesthetic requirements of halothane and isoflurane was studied before and after administration of acepromazine maleate (0.2 mg/kg). Insufficient data has been obtained to date to draw conclusions on any possible drug interactions.

Novel polymeric bioerodable microparticles for prolonged-release intrathecal delivery of analgesic agents for relief of intractable cancer-related pain.

PubMed

Han, Felicity Y; Thurecht, Kristofer J; Lam, Ai-Leen; Whittaker, Andrew K; Smith, Maree T

2015-07-01

Intractable cancer-related pain complicated by a neuropathic component due to nerve impingement is poorly alleviated even by escalating doses of a strong opioid analgesic. To address this unmet medical need, we developed sustained-release, bioerodable, hydromorphone (potent strong opioid)- and ketamine (analgesic adjuvant)-loaded microparticles for intrathecal (i.t.) coadministration. Drug-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles were prepared using a water-in-oil-in-water method with evaporation. Encapsulation efficiency of hydromorphone and ketamine in PLGA (50:50) microparticles was 26% and 56%, respectively. Microparticles had the desired size range (20-60 μm) and in vitro release was prolonged at ≥28 days. Microparticles were stable for ≥6 months when stored refrigerated protected from light in a desiccator. Desirably, i.t. injected fluorescent dye-labeled PLGA microparticles in rats remained in the lumbar region for ≥7 days. In a rat model of neuropathic pain, i.t. coinjection of hydromorphone- and ketamine-loaded microparticles (each 1 mg) produced analgesia for 8 h only. Possible explanations include inadequate release of ketamine and/or hydromorphone into the spinal fluid, and/or insufficient ketamine loading to prevent development of analgesic tolerance to the released hydromorphone. As sub-analgesic doses of i.t. ketamine at 24-48 h intervals restored analgesia on each occasion, insufficient ketamine loading appears problematic. We will investigate these issues in future work. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

Only extra-high dose of ketamine affects l-glutamate-induced intracellular Ca(2+) elevation and neurotoxicity.

PubMed

Shibuta, Satoshi; Morita, Tomotaka; Kosaka, Jun; Kamibayashi, Takahiko; Fujino, Yuji

2015-09-01

The neurotoxic effects of anesthetics on the developing brain are a concern. Although most of the anesthetics are GABAA agonists or NMDA antagonists, the differences in these effects on prospective glutamate-neurotoxicity in the brain is not fully understood. We examined the degree of L-glutamate-induced intracellular calcium ([Ca(2+)]i) elevation and neurotoxicity in neurons exposed to anesthetics. Primary cortical neurons from E17 rats were preincubated with 1-100 μM of ketamine or thiopental sodium (TPS) for the first 72 h of culturing. Two weeks later, the neurons were exposed to L-glutamate. The extent of glutamate toxicity was evaluated using Ca(2+)-imaging and morphological experiments. Preincubation with 100 μM ketamine but not with other concentrations of ketamine and TPS for the first 72 h in culture significantly enhanced L-glutamate-induced [Ca(2+)]i elevation 2 weeks later. Morphology experiments showed that vulnerability to L-glutamate-mediated neurotoxicity was only altered in neurons preincubated with 100 μM ketamine but not with TPS. Although preincubation with high concentration of ketamine showed enhancement of L-glutamate-induced [Ca(2+)]i elevation 2 weeks later, long-term exposure to TPS or ketamine at clinical doses during developmental periods may not result in a dose-related potentiation of exogenous glutamate-induced neurotoxicity, once the intravenous anesthetics are discontinued. Copyright © 2015 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

COMPARISON OF INTRAOPERATIVE KETAMINE VS. FENTANYL USE DECREASES POSTOPERATIVE OPIOID REQUIREMENTS IN TRAUMA PATIENTS UNDERGOING CERVICAL SPINE SURGERY.

PubMed

Berkowitz, Aviva C; Ginsburg, Aryeh M; Pesso, Raymond M; Angus, George L D; Kang, Amiee; Ginsburg, Dov B

2016-02-01

Postoperative airway compromise following cervical spine surgery is a potentially serious adverse event. Residual effects of anesthesia and perioperative opioids that can cause both sedation and respiratory depression further increase this risk. Ketamine is an N-methyl-d-aspartate (NMDA) receptor antagonist that provides potent analgesia without noticeable respiratory depression. We investigated whether intraoperative ketamine administration could decrease perioperative opioid requirements in trauma patients undergoing cervical spine surgery. We retrospectively reviewed anesthesia records identifying cervical spine surgeries performed between March 2014 and February 2015. All patients received a balanced anesthetic technique utilizing sevoflurane 0.5 minimum alveolar concentration (MAC) and propofol infusion (50-100 mcg/kg/min). For intraoperative analgesia, one group of patients received ketamine (N=25) and a second group received fentanyl (N=27). Cumulative opioid doses in the recovery room and until 24 hours postoperatively were recorded. Fewer patients in the ketamine group (11/25 [44%] vs. 20/27 [74%], respectively; p = 0.03) required analgesics in the recovery room. Additionally, the total cumulative opioid requirements in the ketamine group decreased postoperatively at both 3 and 6 hours (p = 0.01). Ketamine use during cervical spine surgery decreased opioid requirements in both the recovery room and in the first 6 hours postoperatively. This may have the potential to minimize opioid induced respiratory depression in a population at increased risk of airway complications related to the surgical procedure.

The Effects of Low-Dose Ketamine on Acute Pain in an Emergency Setting: A Systematic Review and Meta-Analysis.

PubMed

Lee, Eun Nam; Lee, Jae Hoon

2016-01-01

Currently ketamine is not used often as an analgesic in the emergency department (ED). Nonetheless, it can increase the efficiency of opioids and decrease their side effects. The purpose of this systematic review and meta-analysis was to evaluate whether low-dose ketamine in the ED provides better analgesia with fewer adverse effects. The PubMed, EMBASE, and Cochrane Library databases were searched by two reviewers independently (last search performed on January 2016). Data were also extracted independently. A total of 6 trials involving 438 patients were included in the current analysis. Our subgroup analysis of pain reduction indicates that the favorable effects of ketamine were similar or superior to those of placebo or opioids, although these effects were heterogeneous. However, low-dose ketamine was associated with a higher risk of neurological (relative risk [RR] = 2.17, 95% confidence interval [CI] = 1.37-3.42, P < 0.001) and psychological events (RR = 13.86, 95% CI = 4.85-39.58, P < 0.001). In contrast, the opioid group had a higher risk of major cardiopulmonary events (RR = 0.22, 95% CI = 0.05-1.01, P = 0.05). The efficiency of ketamine varies depending on the pain site, but low-dose ketamine may be a key agent for pain control in the ED, as it has no side effects. It may also help to reduce the side effects of opioids.

The Effects of Low-Dose Ketamine on Acute Pain in an Emergency Setting: A Systematic Review and Meta-Analysis

PubMed Central

2016-01-01

Objectives Currently ketamine is not used often as an analgesic in the emergency department (ED). Nonetheless, it can increase the efficiency of opioids and decrease their side effects. The purpose of this systematic review and meta-analysis was to evaluate whether low-dose ketamine in the ED provides better analgesia with fewer adverse effects. Methods The PubMed, EMBASE, and Cochrane Library databases were searched by two reviewers independently (last search performed on January 2016). Data were also extracted independently. Results A total of 6 trials involving 438 patients were included in the current analysis. Our subgroup analysis of pain reduction indicates that the favorable effects of ketamine were similar or superior to those of placebo or opioids, although these effects were heterogeneous. However, low-dose ketamine was associated with a higher risk of neurological (relative risk [RR] = 2.17, 95% confidence interval [CI] = 1.37–3.42, P < 0.001) and psychological events (RR = 13.86, 95% CI = 4.85–39.58, P < 0.001). In contrast, the opioid group had a higher risk of major cardiopulmonary events (RR = 0.22, 95% CI = 0.05–1.01, P = 0.05). Conclusions The efficiency of ketamine varies depending on the pain site, but low-dose ketamine may be a key agent for pain control in the ED, as it has no side effects. It may also help to reduce the side effects of opioids. PMID:27788221

Ketamine-based anesthesia improves electroconvulsive therapy outcomes: a randomized-controlled study.

PubMed

Gamble, Jonathan J; Bi, Henry; Bowen, Rudy; Weisgerber, Grahme; Sanjanwala, Rohan; Prasad, Renuka; Balbuena, Lloyd

2018-06-01

Major depressive disorder (MDD) is a common and debilitating condition that can be challenging to treat. Electroconvulsive therapy (ECT) is currently the therapeutic gold standard for treatment-resistant MDD. We tested our hypothesis that ketamine-based anesthesia for ECT results in superior improvement in treatment-resistant MDD outcomes compared with propofol-based anesthesia. Patients with treatment-resistant MDD were enrolled in a randomized clinical trial with assignment to ketamine- or propofol-based anesthesia arms. Using a modified intention-to-treat analysis, we compared the median number of ECT treatments required to achieve a 50% reduction (primary outcome) and a score ≤ 10 (secondary outcome) on the Montgomery-Asberg depression rating scale (MADRS) between anesthesia groups. The study was terminated as significant results were found after the first planned interim analysis with 12 patients in each of the ketamine (intervention) and propofol (control) groups. All ketamine patients achieved at least a 50% MADRS reduction after a median of two ECT treatments whereas ten propofol patients (83%) achieved the same outcome after a median of four ECT treatments. All ketamine patients and seven propofol patients (58%) achieved MDD remission (MADRS ≤ 10). Log rank tests showed that both time-to-50% reduction and remission differed significantly between groups. Adverse events and recovery time were similar between groups. In this early-terminated small-sized study, ketamine-based anesthesia compared with propofol-based anesthesia provided response and remission after fewer ECT sessions. www.clinicaltrials.gov (NCT01935115). Registered 4 September 2013.

Pretreatment with minocycline restores neurogenesis in the subventricular zone and subgranular zone of the hippocampus after ketamine exposure in neonatal rats.

PubMed

Lu, Yang; Giri, P K; Lei, Shan; Zheng, Juan; Li, Weisong; Wang, Ning; Chen, Xinlin; Lu, Haixia; Zuo, Zhiyi; Liu, Yong; Zhang, Pengbo

2017-06-03

Ketamine is commonly used for anesthesia in pediatric patients. Recent studies indicated that ketamine exposure in the developing brain can induce neuroapoptosis and disturb normal neurogenesis, which will result in long-lasting cognitive impairment. Minocycline exerts neuroprotection against a wide range of toxic insults in neurodegenerative disease models. In the present study, we investigated whether the disturbed neurogenesis and behavioral deficits after ketamine neonatal exposure could be alleviated by minocycline. Postnatal day (PND)7 Sprague-Dawley rat pups randomly received either normal saline, ketamine, or minocycline 30min prior to ketamine administration, respectively. The rats were decapitated at PND14 for the detection of neurogenesis in the subventricular zone (SVZ) and subgranular zone (SGZ) of the hippocampus by immunostaining. The protein expression of p-Akt, p-GSK-3β in the SVZ and SGZ at 12h after anesthesia, PND10 and PND14 were assessed by western blotting analysis. At PND 42-47, spatial learning and memory abilities were measured by the Morris water maze in all groups. Our data showed that ketamine exposure in neonatal rats resulted in neurogenetic damage and persistent cognitive deficits, and that pretreatment with minocycline eliminated the brain development damage and improved the behavioral function in adult rats. Moreover, the protection of minocycline is associated with the PI3K/Akt signaling pathway. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Ketamine augmentation of electroconvulsive therapy to improve neuropsychological and clinical outcomes in depression (Ketamine-ECT): a multicentre, double-blind, randomised, parallel-group, superiority trial.

PubMed

Anderson, Ian M; Blamire, Andrew; Branton, Tim; Clark, Ross; Downey, Darragh; Dunn, Graham; Easton, Andrew; Elliott, Rebecca; Elwell, Clare; Hayden, Katherine; Holland, Fiona; Karim, Salman; Loo, Colleen; Lowe, Jo; Nair, Rajesh; Oakley, Timothy; Prakash, Antony; Sharma, Parveen K; Williams, Stephen R; McAllister-Williams, R Hamish

2017-05-01

The use of electroconvulsive therapy (ECT) is limited by concerns about its cognitive adverse effects. Preliminary evidence suggests that administering the glutamate antagonist ketamine with ECT might alleviate cognitive adverse effects and accelerate symptomatic improvement; we tested this in a randomised trial of low-dose ketamine. In this multicentre, randomised, parallel-group study in 11 ECT suites serving inpatient and outpatient care settings in seven National Health Service trusts in the North of England, we recruited severely depressed patients, who were diagnosed as having unipolar or bipolar depressive episodes defined as moderate or severe by DSM-IV criteria, aged at least 18 years, and were able and willing to provide written consent to participate in the study. Patients were randomly assigned (1:1) to ketamine (0·5 mg/kg intravenous bolus) or saline adjunctive to the anaesthetic for the duration of their ECT course. Patients and assessment and ECT treatment teams were masked to treatment allocation, although anaesthetists administering the study medication were not. We analysed the primary outcome, Hopkins Verbal Learning Test-Revised delayed verbal recall (HVLT-R-DR) after four ECT treatments, using a Gaussian repeated measures model in all patients receiving the first ECT treatment. In the same population, safety was assessed by adverse effect monitoring. This trial was registered with International Standard Randomised Controlled Trial Number, number ISRCTN14689382. Between early December, 2012, and mid-June, 2015, 628 patients were screened for eligibility, of whom 79 were randomly assigned to treatment (40 in the ketamine group vs 39 in the saline group). Ketamine (mean 5·17, SD 2·92), when compared with saline (5·54, 3·42), had no benefit on the primary outcome (HVLT-R-DR; difference in means -0·43 [95% CI -1·73 to 0·87]). 15 (45%) of 33 ketamine-treated patients compared with 10 (27%) of 37 patients receiving saline experienced at least one adverse event which included two (6%) of 33 patients who had ketamine-attributable transient psychological effects. Psychiatric adverse events were the most common in both groups (six [27%] of 22 adverse events in the ketamine group vs seven [54%] of 13 in the saline group). No evidence of benefit for ketamine was found although the sample size used was small; however, the results excluded greater than a small to moderate benefit with 95% confidence. The results do not support the use of adjunctive low-dose ketamine in routine ECT treatment. National Institute for Health Research (NIHR) Efficacy and Mechanism Evaluation (EME) programme, an MRC and NIHR partnership. Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.

Prehospital Pain Medication Use by U.S. Forces in Afghanistan

DTIC Science & Technology

2015-03-01

oral transmucosal fentanyl citrate were the most commonly used pain medications during POI care, whereas ketamine and fentanyl predominated during...difference in vital signs on arrival to the hospital between casualties who received no pain medication, morphine, fentanyl , or ketamine during TACEVAC. In...this convenience sample, fentanyl and ketamine were as safe as morphine for prehospital use within the dose ranges administered. Future efforts to

The Physiological Bases for Microbial Barotolerance.

DTIC Science & Technology

1981-03-31

in general like halothane or methoxyflurane in its inhibitory action and has approximately the same potency. Ketamine at a 6 mM concentration can...Moreover, the inhibitory action of ketamine was increased by hydrostatic pressure, as is the action of halothane or methoxyflurane . {See Table 1 for...exemplified by ketamine, halothane and methoxyflurane . Their actions are enhanced by hydrostatic pressure and also by helium pressure, as indicated by the

Rectal Thiopental versus Intramuscular Ketamine in Pediatric Procedural Sedation and Analgesia; a Randomized Clinical Trial.

PubMed

Azizkhani, Reza; Esmailian, Mehrdad; Shojaei, Azadeh; Golshani, Keihan

2015-01-01

Physicians frequently deal with procedures which require sedation of pediatric patients. Laceration repair is one of them. No study has been performed regarding the comparison between induction of sedation with sodium thiopental and ketamine in laceration repair. Therefore, the present study was aimed to comparison of induced sedation by rectal sodium thiopental and muscular injection of hydrochloride ketamine in pediatric patients need laceration repair. The presented study is a single-blinded clinical trial performed through 2013 to 2014 in Ayatollah Kashani and Alzahra Hospitals, Isfahan, Iran. Patients from 3 months to 14 years, needed sedation for laceration repair, were entered. Patients were sequentially evaluated and randomly categorized in two groups of hydrochloride ketamine with dose of 2-4 milligram per kilogram and sodium thiopental with dose of 25 milligram per kilogram. Demographic data and vital signs before drug administration and after induction of sedation, Ramsey score, time to onset of action, and sedation recovery time were evaluated. Chi-squared, Mann-Whitney, and Non-parametric analysis of covariance tests were used. P<0.05 was considered as a significant level. In this study 60 pediatric patients were entered. 30 patients with mean age of 42.8±18.82 months were received sodium thiopental and the rest with mean age of 30.08±16.88 months given ketamine. Mann-Whitney test was showed that time to onset of action in sodium thiopental group (28.23±5.18 minutes) was significantly higher than ketamine (7.77±4.13 minutes), (p<0.001). The sedation recovery time in ketamine group (29.83±7.70) was higher than sodium thiopental. Depth of sedation had no significant difference between two groups based on Ramsey score (p=0.87). No significant difference was seen between two groups in the respiratory rate (df=1, 58; F=0.002; P=0.96) and heart rate (df=1, 58; F=0.98; P=0.33). However, arterial oxygen saturation level (df=1, 58; F=6.58; P=0.013) was significantly higher in ketamine group. The findings of the present study show that Although the recovery time from sedation by ketamine is more than sodium thiopental, it's fast-acting function without effecting on the oxygen saturation level causes that ketamine is considered as the better choice for induction of sedation in pediatric patients need laceration repair. In addition, long-term effect of ketamine provides more time for the physician to do the procedure and this issue decreases the need probability to the repeated-dose. However, effectiveness of both drugs to decrease the agitation was equal, based on the Ramsey score.

Ketamine and phencyclidine: the good, the bad and the unexpected

PubMed Central

Lodge, D; Mercier, M S

2015-01-01

The history of ketamine and phencyclidine from their development as potential clinical anaesthetics through drugs of abuse and animal models of schizophrenia to potential rapidly acting antidepressants is reviewed. The discovery in 1983 of the NMDA receptor antagonist property of ketamine and phencyclidine was a key step to understanding their pharmacology, including their psychotomimetic effects in man. This review describes the historical context and the course of that discovery and its expansion into other hallucinatory drugs. The relevance of these findings to modern hypotheses of schizophrenia and the implications for drug discovery are reviewed. The findings of the rapidly acting antidepressant effects of ketamine in man are discussed in relation to other glutamatergic mechanisms. PMID:26075331

Initial Experience with IV Ketamine Infusion for Treatment of Post Sternotomy Pain in a Patient with a Total Artificial Heart.

PubMed

Maher, Dermot P; Loyferman, Rusty; Yumul, Roya; Louy, Charles

2015-01-01

The implantation of total artificial hearts (TAH) via midline sternotomy for the treatment of severe biventricular cardiac dysfunction is associated with complex postoperative pain management. Ketamaine increases blood pressure by raising sympathetic outflow and cardiac output; however, ketamine is a direct vasodilator on isolated arterial tissues. In the setting of a TAH with a mechanically fixed cardiac output, a ketamine infusion for postoperative pain control has the potential to decrease blood pressure due to direct arterial vasodilation. We present the initial experience with a ketamine infusion in a patient with a TAH with minimal observed decreases in blood pressure and significantly improved postoperative pain.

Comparison of the Effect of Thiopental Sodium with Midazolam-ketamine on Post-tonsillectomy Agitation in Children.

PubMed

Toliyat, Maryam; Zangoee, Maliheh; Ahrari, Shahnaz; Zangoee, Reza

2015-10-01

The aim of this study was to determine the effect of thiopental sodium with that of midazolam-ketamine on relieving agitation after tonsillectomy in children. In a clinical trial, 50 children aged 5-10 years, candidates for tonsillectomy, were randomly divided into two 25-member groups. In the first group, thiopental sodium 5mg/kg/IV, and in the second group combination of midazolam 0.01 mg/kg/IV and ketamine 1 mg/kg/IV were used to induce anesthesia. The level of sedation was assessed after surgery with the Ramsay scale. There were no significant differences between the two groups in terms of heart rate, arterial oxygen pressure (PO2), and duration of anesthesia. The Ramsay sedation score was significantly higher in the thiopental sodium group than in the midazolam-ketamine group (P=0.01). Thiopental sodium can be more effective than the combination of midazolam-ketamine for controlling agitation after tonsillectomy in children.

A randomized controlled trial of intranasal ketamine in migraine with prolonged aura.

PubMed

Afridi, Shazia K; Giffin, Nicola J; Kaube, Holger; Goadsby, Peter J

2013-02-12

The aim of our study was to test the hypothesis that ketamine would affect aura in a randomized controlled double-blind trial, and thus to provide direct evidence for the role of glutamatergic transmission in human aura. We performed a double-blinded, randomized parallel-group controlled study investigating the effect of 25 mg intranasal ketamine on migraine with prolonged aura in 30 migraineurs using 2 mg intranasal midazolam as an active control. Each subject recorded data from 3 episodes of migraine. Eighteen subjects completed the study. Ketamine reduced the severity (p = 0.032) but not duration of aura in this group, whereas midazolam had no effect. These data provide translational evidence for the potential importance of glutamatergic mechanisms in migraine aura and offer a pharmacologic parallel between animal experimental work on cortical spreading depression and the clinical problem. This study provides class III evidence that intranasal ketamine is effective in reducing aura severity in patients with migraine with prolonged aura.

The Future of Intensive Care Unit Sedation: A Report of Continuous Infusion Ketamine as an Alternative Sedative Agent.

PubMed

Benken, Scott T; Goncharenko, Alexandra

2017-10-01

This report describes a patient case utilizing a nontraditional sedative, continuous infusion ketamine, as an alternative agent for intensive care unit (ICU) sedation. A 27-year-old female presented for neurosurgical management of a coup contrecoup injury, left temporal fracture, epidural hemorrhage (EDH), and temporal contusion leading to sustained mechanical ventilation. The patient experienced profound agitation during mechanical ventilation and developed adverse effects with all traditional sedatives: benzodiazepines, dexmedetomidine, opioids, and propofol. Ketamine was titrated to effect and eliminated the need for other agents. This led to successful ventilator weaning, extubation, and transition of care. Given the unique side effect profile of ketamine, it is imperative that information is disseminated on potential utilization of this agent. More information is needed regarding dosing, monitoring, and long-term effects of utilizing ketamine as a continuous ICU sedative, but given the analgesia, anesthesia, and cardiopulmonary stability, future utilization of this medication for this indication seems promising.

Ketamine blocks bursting in the lateral habenula to rapidly relieve depression.

PubMed

Yang, Yan; Cui, Yihui; Sang, Kangning; Dong, Yiyan; Ni, Zheyi; Ma, Shuangshuang; Hu, Hailan

2018-02-14

The N-methyl-d-aspartate receptor (NMDAR) antagonist ketamine has attracted enormous interest in mental health research owing to its rapid antidepressant actions, but its mechanism of action has remained elusive. Here we show that blockade of NMDAR-dependent bursting activity in the 'anti-reward center', the lateral habenula (LHb), mediates the rapid antidepressant actions of ketamine in rat and mouse models of depression. LHb neurons show a significant increase in burst activity and theta-band synchronization in depressive-like animals, which is reversed by ketamine. Burst-evoking photostimulation of LHb drives behavioural despair and anhedonia. Pharmacology and modelling experiments reveal that LHb bursting requires both NMDARs and low-voltage-sensitive T-type calcium channels (T-VSCCs). Furthermore, local blockade of NMDAR or T-VSCCs in the LHb is sufficient to induce rapid antidepressant effects. Our results suggest a simple model whereby ketamine quickly elevates mood by blocking NMDAR-dependent bursting activity of LHb neurons to disinhibit downstream monoaminergic reward centres, and provide a framework for developing new rapid-acting antidepressants.

Plasma brain derived neurotrophic factor (BDNF) and response to ketamine in treatment-resistant depression.

PubMed

Haile, C N; Murrough, J W; Iosifescu, D V; Chang, L C; Al Jurdi, R K; Foulkes, A; Iqbal, S; Mahoney, J J; De La Garza, R; Charney, D S; Newton, T F; Mathew, S J

2014-02-01

Ketamine produces rapid antidepressant effects in treatment-resistant depression (TRD), but the magnitude of response varies considerably between individual patients. Brain-derived neurotrophic factor (BDNF) has been investigated as a biomarker of treatment response in depression and has been implicated in the mechanism of action of ketamine. We evaluated plasma BDNF and associations with symptoms in 22 patients with TRD enrolled in a randomized controlled trial of ketamine compared to an anaesthetic control (midazolam). Ketamine significantly increased plasma BDNF levels in responders compared to non-responders 240 min post-infusion, and Montgomery-Åsberg Depression Rating Scale (MADRS) scores were negatively correlated with BDNF (r=-0.701, p = 0.008). Plasma BDNF levels at 240 min post-infusion were highly negatively associated with MADRS scores at 240 min (r = -0.897, p=.002), 24 h (r = -0.791, p = 0.038), 48 h (r = -0.944, p = 0.001) and 72 h (r = -0.977, p = 0.010). No associations with BDNF were found for patients receiving midazolam. These data support plasma BDNF as a peripheral biomarker relevant to ketamine antidepressant response.

Intraoperative low-dose ketamine infusion reduces acute postoperative pain following total knee replacement surgery: a prospective, randomized double-blind placebo-controlled trial.

PubMed

Cengiz, Pelin; Gokcinar, Derya; Karabeyoglu, Isil; Topcu, Hulya; Cicek, Gizem Selen; Gogus, Nermin

2014-05-01

To evaluate the effect of intraoperative low-dose ketamine with general anesthesia on postoperative pain after total knee replacement surgery. A randomized, double-blind comparative study. Ankara Numune Training and Research Hospital, Turkey, from January and June 2011. Sixty adults undergoing total knee arthroplasty were enrolled in this study. The patients were randomly allocated into two groups of equal size to receive either racemic ketamine infusion (6 μg/kg/minute) or the same volume of saline. A visual analogue scale (VAS) was used to measure each patient's level of pain at 1, 3, 6, 12, and 24 hours after surgery. Time to first analgesic request, postoperative morphine consumption and the incidence of side effects were also recorded. Low-dose ketamine infusion prolonged the time to first analgesic request. It also reduced postoperative cumulative morphine consumption at 1, 3, 6, 12, and 24 hours postsurgery (p < 0.001). Postoperative VAS scores were also significantly lower in the ketamine group than placebo, at all observation times. Incidences of side effects were similar in both study groups. Intraoperative continuous low-dose ketamine infusion reduced pain and postoperative analgesic consumption without affecting the incidence of side effects.

Ketamine-snorting associated cystitis.

PubMed

Chen, Chung-Hsien; Lee, Ming-Huei; Chen, Yi-Chang; Lin, Ming-Fong

2011-12-01

Ketamine hydrochloride, commonly used as a pediatric anesthetic agent, is an N-methyl-D-aspartic (NMDA) acid receptor antagonist with rapid onset and short duration of action. It produces a cataleptic-like state where the patient is dissociated from the surrounding environment by direct action on the cortex and limbic system. It has emerged as an increasingly popular choice among young drug users, especially within dance club venues. Cases of bladder dysfunction among recreational ketamine users were reported since Shahani et al first reported nine cases of ketamine-associated ulcerative cystitis in 2007. We report on four patients who had history of ketamine abuse, presenting with dysuria, fluctuating lower urinary tract symptoms (LUTS), lower abdominal or perineal pain, and impaired functional bladder capacities. Urinalysis showed pyuria and microhematuria. Urine culture was sterile. Bladder ulceration with severe diffuse hemorrhage and low bladder capacity were noted under anesthetized cystoscopic examination. Transurethral bladder mucosa biopsy was consistent with chronic cystitis. Cessation of ketamine abuse was the milestone of treatment, followed by the administration of mucosal protective agents, such as pentosan polysulphate or hyaluronic acid. Suprapubic pain was improved in three patients during follow-up. However, the outcome of treatment depends on the severity of the disease process, similar to that of interstitial cystitis (IC). Copyright © 2011. Published by Elsevier B.V.

Ketamine modulation of the haemodynamic response to spreading depolarization in the gyrencephalic swine brain

PubMed Central

Santos, Edgar; Schöll, Michael; Kunzmann, Kevin; Stock, Christian; Silos, Humberto; Unterberg, Andreas W; Sakowitz, Oliver W

2016-01-01

Spreading depolarization (SD) generates significant alterations in cerebral haemodynamics, which can have detrimental consequences on brain function and integrity. Ketamine has shown an important capacity to modulate SD; however, its impact on SD haemodynamic response is incompletely understood. We investigated the effect of two therapeutic ketamine dosages, a low-dose of 2 mg/kg/h and a high-dose of 4 mg/kg/h, on the haemodynamic response to SD in the gyrencephalic swine brain. Cerebral blood volume, pial arterial diameter and cerebral blood flow were assessed through intrinsic optical signal imaging and laser-Doppler flowmetry. Our findings indicate that frequent SDs caused a persistent increase in the baseline pial arterial diameter, which can lead to a diminished capacity to further dilate. Ketamine infused at a low-dose reduced the hyperemic/vasodilative response to SD; however, it did not alter the subsequent oligemic/vasoconstrictive response. This low-dose did not prevent the baseline diameter increase and the diminished dilative capacity. Only infusion of ketamine at a high-dose suppressed SD and the coupled haemodynamic response. Therefore, the haemodynamic response to SD can be modulated by continuous infusion of ketamine. However, its use in pathological models needs to be explored to corroborate its possible clinical benefit. PMID:27126324

Depression in chronic ketamine users: Sex differences and neural bases.

PubMed

Li, Chiang-Shan R; Zhang, Sheng; Hung, Chia-Chun; Chen, Chun-Ming; Duann, Jeng-Ren; Lin, Ching-Po; Lee, Tony Szu-Hsien

2017-11-30

Chronic ketamine use leads to cognitive and affective deficits including depression. Here, we examined sex differences and neural bases of depression in chronic ketamine users. Compared to non-drug using healthy controls (HC), ketamine-using females but not males showed increased depression score as assessed by the Center of Epidemiological Studies Depression Scale (CES-D). We evaluated resting state functional connectivity (rsFC) of the subgenual anterior cingulate cortex (sgACC), a prefrontal structure consistently implicated in the pathogenesis of depression. Compared to HC, ketamine users (KU) did not demonstrate significant changes in sgACC connectivities at a corrected threshold. However, in KU, a linear regression against CES-D score showed less sgACC connectivity to the orbitofrontal cortex (OFC) with increasing depression severity. Examined separately, male and female KU showed higher sgACC connectivity to bilateral superior temporal gyrus and dorsomedial prefrontal cortex (dmPFC), respectively, in correlation with depression. The linear correlation of sgACC-OFC and sgACC-dmPFC connectivity with depression was significantly different in slope between KU and HC. These findings highlighted changes in rsFC of the sgACC as associated with depression and sex differences in these changes in chronic ketamine users. Copyright © 2017 Elsevier B.V. All rights reserved.