Enhancement of the anti-immobility action of antidepressants by risperidone in the forced swimming test in mice.

PubMed

Rogóż, Zofia; Kabziński, Marcin

2011-01-01

The aim of the present study was to examine the effect of antidepressants (ADs) belonging to different pharmacological groups and risperidone (an atypical antipsychotic drug), given separately or jointly, on immobility time in the forced swimming test in male C57BL/6J mice. The antidepressants: citalopram, fluvoxamine, sertraline, reboxetine, milnacipran (5 and 10 mg/kg), or risperidone in low doses (0.05 and 0.1 mg/kg) given alone did not change the immobility time of mice in the forced swimming test. Co-treatment with reboxetine or milnacipran (10 mg/kg) and risperidone in a lower dose of 0.05 mg/kg or with sertraline, reboxetine (5 and 10 mg/kg), citalopram, fluvoxamine, milnacipran (10 mg/kg) and risperidone in a higher dose of 0.1 mg/kg produced antidepressant-like effect in the forced swimming test. WAY100635 (a 5-HT(1A) receptor antagonist) inhibited the effects induced by co-administration of ADs and risperidone. Active behavior in the forced swimming test was not a consequence of an increased general activity, since the combined treatment with ADs and risperidone failed to enhance the locomotor activity of mice. The obtained results indicate that a low dose of risperidone enhances the activity of ADs in an animal model of depression, and that, among other mechanisms, 5-HT(1A) receptors may play a role in these effects.

The Neurotensin NTS1 Receptor Agonist PD149163 Produces Antidepressant-Like Effects in the Forced Swim Test: Further Support for Neurotensin as a Novel Pharmacologic Strategy for Antidepressant Drugs.

PubMed

Carey, Lawrence M; Rice, Remington J; Prus, Adam J

2017-08-01

Preclinical Research Neurotensin is a nonbrain penetrant neuropeptide neurotransmitter that alters dopaminergic and serotonergic neurotransmission. Previous animal behavioral studies have demonstrated that intra-ventral tegmental administration of neurotensin and system administration of the selective neurotensin NTS 1 receptor agonist, PD149163 produce antidepressant-like effects in a forced swim test and a differential reinforcement of low rate task, respectively. The present study sought to expand upon these past findings by assessing systemic administration of PD149163 in a forced swim test, a primary antidepressant preclinical screening model, in mice. The tricyclic antidepressant drug imipramine was tested for comparison, and both compounds were also assessed in an open field test. Both PD149163 and imipramine reduced time spent immobile, an antidepressant-like effect, in the forced swim test. The highest dose of each compound significantly reduced locomotor activity. These findings provide further evidence for the putative antidepressant effects for PD149163 and suggest that NTS 1 receptor activation may be a novel pharmacologic strategy for antidepressant drug development. Drug Dev Res 78 : 196-202, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Omega-3 fatty acids have antidepressant activity in forced swimming test in Wistar rats.

PubMed

Lakhwani, Lalit; Tongia, Sudheer K; Pal, Veerendra S; Agrawal, Rajendra P; Nyati, Prem; Phadnis, Pradeep

2007-01-01

Forced swimming test is used to induce a characteristic behavior of immobility in rats, which resembles depression in humans to some extent. We evaluated the effect of omega-3 fatty acids alone as well as compared it with the standard antidepressant therapy with fluoxetine in both acute and chronic studies. In both the studies, rats were divided into 4 groups and subjected to the following drug interventions - Group 1- control: Group 2- fluoxetine in dose of 10 mg/kg subcutaneously 23.5, 5 and 1 h before the test: Group 3- omega-3 fatty acids in dose of 500 mg/kg orally; Group 4- fluoxetine plus omega-3 fatty acids both. In acute study, omega-3 fatty acids were given in single dose 2 h prior to the test while in chronic study omega-3 fatty acids were given daily for a period of 28 days. All animals were subjected to a 15-min pretest followed 24 h later by a 5-min test. A time sampling method was used to score the behavioral activity in each group. The results revealed that in acute study, omega-3 fatty acids do not have any significant effect in forced swimming test. However, in chronic study, omega-3 fatty acids affect the immobility and swimming behavior significantly when compared with control (p < 0.01) without any significant effect on climbing behavior and the efficacy of combination of omega-3 fatty acids and fluoxetine is significantly more than that of fluoxetine alone in changing the behavioral activity of rats in forced swimming test. It leads to the conclusion that omega-3 fatty acids have antidepressant activity per se, and the combination of fluoxetine and omega-3 fatty acids has more antidepressant efficacy than fluoxetine alone in forced swimming test in Wistar rats.

Effect of desipramine and citalopram treatment on forced swimming test-induced changes in cocaine- and amphetamine-regulated transcript (CART) immunoreactivity in mice.

PubMed

Chung, Sung; Kim, Hee Jeong; Kim, Hyun Ju; Choi, Sun Hye; Kim, Jin Wook; Kim, Jeong Min; Shin, Kyung Ho

2014-05-01

Recent study demonstrates antidepressant-like effect of cocaine- and amphetamine-regulated transcript (CART) in the forced swimming test (FST), but less is known about whether antidepressant treatments alter levels of CART immunoreactivity (CART-IR) in the FST. To explore this possibility, we assessed the treatment effects of desipramine and citalopram, which inhibit the reuptake of norepinephrine and serotonin into the presynaptic terminals, respectively, on changes in levels of CART-IR before and after the test swim in mouse brain. Levels of CART-IR in the nucleus accumbens shell (AcbSh), dorsal bed nucleus of the stria terminalis (dBNST), and hypothalamic paraventricular nucleus (PVN) were significantly increased before the test swim by desipramine and citalopram treatments. This increase in CART-IR in the AcbSh, dBNST, and PVN before the test swim remained elevated by desipramine treatment after the test swim, but this increase in these brain areas returned to near control levels after test swim by citalopram treatment. Citalopram, but not desipramine, treatment increased levels of CART-IR in the central nucleus of the amygdala (CeA) and the locus ceruleus (LC) before the test swim, and this increase was returned to control levels after the test swim in the CeA, but not in the LC. These results suggest common and distinct regulation of CART by desipramine and citalopram treatments in the FST and raise the possibility that CART in the AcbSh, dBNST, and CeA may be involved in antidepressant-like effect in the FST.

Effects of chronic forced-swim stress on behavioral properties in rats with neonatal repeated MK-801 treatment.

PubMed

Kawabe, Kouichi

2017-08-01

The two-hit hypothesis has been used to explain the onset mechanism of schizophrenia. It assumes that predisposition to schizophrenia is originally attributed to vulnerability in the brain which stems from genetic or early developmental factors, and that onset is triggered by exposure to later detrimental factors such as stress in adolescence or adulthood. Based on this hypothesis, the present study examined whether rats that had received neonatal repeated treatment with an N-methyl-d-aspartate (NMDA) receptor antagonist (MK-801), an animal model of schizophrenia, were vulnerable to chronic stress. Rats were treated with MK-801 (0.2mg/kg) or saline twice daily on postnatal days 7-20, and animals in the stress subgroups were subjected to 20days (5days/week×4weeks) of forced-swim stress in adulthood. Following this, behavioral tests (prepulse inhibition, spontaneous alternation, open-field, and forced-swim tests) were carried out. The results indicate that neonatal repeated MK-801 treatment in rats inhibits an increase in immobility in the forced-swim test after they have experienced chronic forced-swim stress. This suggests that rats that have undergone chronic neonatal repeated NMDA receptor blockade could have a reduced ability to habituate or adapt to a stressful situation, and supports the hypothesis that these rats are sensitive or vulnerable to stress. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of co-administration of fluoxetine or tianeptine with metyrapone on immobility time and plasma corticosterone concentration in rats subjected to the forced swim test.

PubMed

Rogóz, Zofia; Skuza, Grazyna; Leśkiewicz, Monika; Budziszewska, Bogusława

2008-01-01

Major depression is frequently associated with hyperactivity of the hypothalamic-pituitary-adrenocortical axis, and glucocorticoid synthesis inhibitors have been shown to exert antidepressant action. The aim of the present study was to examine the effect of co-administration of fluoxetine or tianeptine with metyrapone on immobility time and plasma corticosterone concentration in male Wistar rats subjected to the forced swim test. Metyrapone alone (50 mg/kg, but not 25 mg/kg) reduced the immobility time of rats in the forced swim test; moreover, both doses tested (25 and 50 mg/kg), dose-dependently decreased the stress-induced plasma corticosterone concentration. Joint administration of fluoxetine or tianeptine (10 mg/kg) and metyrapone (25 mg/kg - a dose inactive per se) exhibited antidepressant-like activity in the forced swim test in rats. WAY 100636 (a 5-HT(1A) antagonist), but not prazosin (an alpha(1)-adrenergic antagonist), used in doses ineffective in the forced swim test, inhibited the antidepressant-like effect induced by co-administration of fluoxetine or tianeptine with metyrapone (25 mg/kg). Combined treatment of fluoxetine or tianeptine and metyrapone inhibited stress-induced corticosterone secretion to a similar extent as metyrapone alone. The obtained results indicate that metyrapone potentiates the antidepressant-like activity of fluoxetine or tianeptine and that, among other mechanisms, 5-HT(1A) receptors may play some role in this effect. Moreover, metyrapone exerts a beneficial effect on the stress-induced increase in plasma corticosterone concentration. These findings suggest that the co-administration of metyrapone and an antidepressant drug may be useful for the treatment of drug-resistant depression and/or depression associated with a high cortisol level.

Sex-Dependent Effects of Stress on Immobility Behavior and VTA Dopamine Neuron Activity: Modulation by Ketamine.

PubMed

Rincón-Cortés, Millie; Grace, Anthony A

2017-10-01

Stress constitutes a risk factor across several psychiatric disorders. Moreover, females are more susceptible to stress-related disorders, such as depression, than males. Although dopamine system underactivation is implicated in the pathophysiology of depression, little is known about the female dopamine system at baseline and post-stress. The effects of chronic mild stress were examined on ventral tegmental area dopamine neuron activity and forced swim test immobility by comparing male and female rats. The impact of a single dose of the rapid antidepressant ketamine (10 mg/kg, i.p.) on forced swim test immobility and ventral tegmental area function was then tested. Baseline ventral tegmental area dopamine activity was comparable in both sexes. At baseline, females exhibited roughly double the forced swim test immobility duration than males, which corresponded to ~50% decrease in ventral tegmental area dopamine population activity compared with similarly treated (i.e., post-forced swim test) males. Following chronic mild stress, there was greater immobility duration in both sexes and reduced ventral tegmental area dopamine neuron activity by approximately 50% in males and nearly 75% in females. Ketamine restored behavior and post-forced swim test ventral tegmental area dopamine activity for up to 7 days in females as well as in both male and female chronic mild stress-exposed rats. These data suggest increased female susceptibility to depression-like phenotypes (i.e., greater immobility, ventral tegmental area hypofunction) is associated with higher dopamine system sensitivity to both acute and repeated stress relative to males. Understanding the neural underpinnings of sex differences in stress vulnerability will provide insight into mechanisms of disease and optimizing therapeutic approaches in both sexes. © The Author 2017. Published by Oxford University Press on behalf of CINP.

Individual differences in the elevated plus-maze and the forced swim test.

PubMed

Estanislau, Celio; Ramos, Anna Carolina; Ferraresi, Paula Daniele; Costa, Naiara Fernanda; de Carvalho, Heloisa Maria Cotta Pires; Batistela, Silmara

2011-01-01

The elevated plus-maze is an apparatus composed of enclosed and open (elevated) arms and time spent in the open arms by a rat can be increased/decreased by anxiolytic/anxiogenic agents. In the forced swim test, floating behavior is used as an index of behavioral despair and can be decreased by antidepressant agents. As the comorbidity between anxiety and depression is a remarkable issue in human behavioral disorders, a possible relationship between the behaviors seen in the cited tests is of great relevance. In the present study, fifty-four male rats (Rattus norvegicus) were submitted to a plus-maze session and to a 2-day forced swim protocol. According to their time in the open arms, they were divided into three groups: Low Open, Medium Open and High Open. Some plus-maze measures were found to be coherent with time in the open arms and are suggested to also be reliable anxiety indexes. In the forced swim test, the Low Open group showed decreases in floating duration from forced swim Session 1 to Session 2, an alteration opposite to that observed in the other groups (particularly, the Medium Open group). The Low Open group also showed increases in floating latency, again in sharp contrast with the alteration found in the other groups. Accordingly, positive and negative correlation were found between time in the open arms and floating duration and latency, respectively. Results are compared to previous studies and mediation of the effect by reactivity to aversive stimulation or alterations induced by open arm exposure is discussed. Copyright © 2010 Elsevier B.V. All rights reserved.

Possible involvement of nitric oxide (NO) signaling pathway in the antidepressant-like effect of MK-801(dizocilpine), a NMDA receptor antagonist in mouse forced swim test.

PubMed

Dhir, Ashish; Kulkarni, S K

2008-03-01

L-arginine-nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) is an important signaling pathway involved in depression. With this information, the present study aimed to study the involvement of this signaling pathway in the antidepressant-like action of MK-801 (dizocilpine; N-methyl-d-aspartate receptor antagonist) in the mouse forced-swim test. Total immobility period was recorded in mouse forced swim test for 6 min. MK-801 (5-25 microg/kg., ip) produced a U-shaped curve in reducing the immobility period. The antidepressant-like effect of MK-801 (10 microg/kg, ip) was prevented by pretreatment with L-arginine (750 mg/kg, ip) [substrate for nitric oxide synthase (NOS)]. Pretreatment of mice with 7-nitroindazole (7-NI) (25 mg/kg, ip) [a specific neuronal nitric oxide synthase inhibitor] produced potentiation of the action of subeffective dose of MK-801 (5 microg/kg, ip). In addition, treatment of mice with methylene blue (10 mg/kg, ip) [direct inhibitor of both nitric oxide synthase and soluble guanylate cyclase] potentiated the effect of MK-801 (5 microg/kg, ip) in the forced-swim test. Further, the reduction in the immobility period elicited by MK-801 (10 microg/kg, ip) was also inhibited by pretreatment with sildenafil (5 mg/kg, ip) [phosphodiesterase 5 inhibitor]. The various modulators used in the study and their combination did not produce any changes in locomotor activity per se and in combination with MK-801. MK-801 however, at higher doses (25 microg/kg, ip) produced hyperlocomotion. The results demonstrated the involvement of nitric oxide signaling pathway in the antidepressant-like effect of MK-801 in mouse forced-swim test.

Serotonergic mediation of the effects of fluoxetine, but not desipramine, in the rat forced swimming test.

PubMed

Page, M E; Detke, M J; Dalvi, A; Kirby, L G; Lucki, I

1999-11-01

The forced swimming test (FST) is a behavioral test in rodents that predicts the clinical efficacy of many types of antidepressant treatments. Recently, a behavior sampling technique was developed that scores individual response categories, including swimming, climbing and immobility. Although all antidepressant drugs reduce immobility in the FST, at least two distinct active behavioral patterns are produced by pharmacologically selective antidepressant drugs. Serotonin-selective reuptake inhibitors increase swimming behavior, while drugs acting primarily to increase extracellular levels of norepinephrine or dopamine increase climbing behavior. Distinct patterns of active behaviors in the FST may be mediated by distinct neurotransmitters, but this has not been shown directly. The present study examined the role of serotonin in mediating active behaviors in the forced swimming test after treatment with two antidepressant drugs, the selective serotonin reuptake inhibitor, fluoxetine and the selective norepinephrine reuptake inhibitor, desipramine. Endogenous serotonin was depleted by administering para-cholorophenylalanine (PCPA, 150 mg/kg, IP.) to rats 72 h and 48 h prior to the swim test. Fluoxetine (10 mg/kg, SC) or desipramine (10 mg/kg, SC) was given three times over a 24-h period prior to the FST. Behavioral responses, including immobility, swimming and climbing, were counted during the 5-min test. Pretreatment with PCPA blocked fluoxetine-induced reduction in immobility and increase in swimming behavior during the FST. In contrast, PCPA pretreatment did not interfere with the ability of desipramine to reduce immobility and increase climbing behavior. Depletion of serotonin prevented the behavioral effects of the selective serotonin reuptake inhibitor fluoxetine in the rat FST. Furthermore, depletion of serotonin had no impact on the behavioral effects induced by the selective norepinephrine reuptake inhibitor, desipramine. The effects of antidepressant drugs on FST-induced immobility may be exerted by distinguishable contributions from different neurotransmitter systems.

Just Keep Swimming: Neuroendocrine, Metabolic, and Behavioral Changes After a Forced Swimming Test in Zebrafish.

PubMed

da Rosa, João Gabriel Santos; Barcellos, Heloísa Helena de Alcântara; Idalencio, Renan; Marqueze, Alessandra; Fagundes, Michele; Rossini, Mainara; Variani, Cristiane; Balbinoti, Francine; Tietböhl, Tássia Michele Huff; Rosemberg, Denis Broock; Barcellos, Leonardo José Gil

2017-02-01

In this study, we show that an adaptation of the spinning test can be used as a model to study the exercise-exhaustion-recovery paradigm in fish. This forced swimming test promotes a wide range of changes in the hypothalamus-pituitary-interrenal axis functioning, intermediary metabolism, as well in fish behavior at both exercise and recovery periods. Our results pointed that this adapted spinning test can be considered a valuable tool for evaluating drugs and contaminant effects on exercised fish. This can be a suitable protocol both to environmental-to evaluate contaminants that act in fish energy mobilization and recovery after stressors-and translational perspectives-effects of drugs on exercised or stressed humans.

Stress-induced hyperlocomotion as a confounding factor in anxiety and depression models in mice.

PubMed

Strekalova, T; Spanagel, R; Dolgov, O; Bartsch, D

2005-05-01

Chronic stress is broadly used to model anxiety and depression. However, in chronic stress models, anxiety- and depression-like behaviors might be masked by unspecific effects of stress. We tested whether chronic stress in mice can induce unspecific changes in locomotion, and whether these changes interfere with the measurement of anxiety and forced-swimming behaviors. Also, we studied these latter behaviors in relation to the duration of stress, the lighting conditions during testing, and after the injection of diazepam. We employed a 4-week chronic stress paradigm, adopted from a model of stress-induced anhedonia and a 1-week subchronic stress, both consisting of rat exposure, restraint stress and tail suspension. Chronically stressed mice, tested under bright and moderate illumination, exhibited 'anxiolytic-like' behavior along with prolonged swimming and hyperactivity. These behaviors were not detectable under weak illumination or after the injection of diazepam (0.25 mg/kg). Instead, normal locomotion, increased anxiety and inhibited swimming were revealed under these conditions. Thus, chronic stress can induce hyperlocomotion in mice, which is triggered by acute stressors such as light, and interferes with the evaluation of anxiety and forced swimming. One week of stress did not change locomotion and forced swimming, and increased anxiety irrespective of illumination applied during testing. Our data can possibly explain previously reported contradictions in the behavioral testing of mice with chronic stress models of anxiety and depression.

Antidepressant-like effects of a cocoa polyphenolic extract in Wistar-Unilever rats.

PubMed

Messaoudi, Michaël; Bisson, Jean-François; Nejdi, Amine; Rozan, Pascale; Javelot, Hervé

2008-12-01

Depression is a major public health problem affecting about 12% of the world population. Drugs exist but they have many side effects. In the last few years, natural substances (e.g. flavonoids) have been tested to cure such disorders. Cocoa polyphenolic extract is a complex compound prepared from non-roasted cocoa beans containing high levels of flavonoids. The antidepressant-like effect of cocoa polyphenolic extract was evaluated using the forced swimming test in rats. Cocoa polyphenolic extract significantly reduced the duration of immobility at both doses of 24 mg/kg/14 days and 48 mg/kg/14 days, although no change of motor dysfunction was observed with the two doses tested in the open field. The results of the forced swimming test after a subchronic treatment and after an additional locomotor activity test confirm the assumption that the antidepressant-like effect of cocoa polyphenolic extract in the forced swimming test model is specific. Further, it can be speculated that this effect might be related to its content of active polyphenols.

Tethered Swimming Test: Reliability and the Association to Swimming Performance and Land-based Anaerobic Performance.

PubMed

Nagle Zera, Jacquelyn; Nagle, Elizabeth F; Nagai, Takashi; Lovalekar, Mita; Abt, John P; Lephart, Scott M

2018-02-14

The purpose of this study was three-fold: (a) to examine the test-retest reliability of a 30 second maximal tethered freestyle swimming test (TST), (b) to assess the validity of the TST by examining the association to sprint swimming performance and, (c) to examine the associations between a swim-specific and land-based measure of anaerobic performance. A total of twenty-nine male and female swimmers were recruited to participate in the study. Each participant completed a Wingate Anaerobic cycling test (WAnT), two or four TST, and a 22.9 meter (25 yard), 45.7 meter (50 yard), and 91.4 meter (100 yard) maximal freestyle performance swims (PS). Mean and peak force (Fmean, Fpeak) were recorded for both the WAnT and TST, and average swimming velocity and time were recorded for the PS. Additionally, physiological and perceptual measures were recorded immediate post exercise for all tests. The results of the present investigation showed strong intersession and intrasession reliability (R= 0.821-0.975; p<0.001) for force parameters of the TST. Moderate correlations were found between Fmean and PS time and velocity of all distances, with slightly weaker correlations between Fpeak and the 22.9 meter (time and velocity) and 45.7 meter (velocity) PS. Finally, moderate correlations were found for Fmean and Fpeak of the TST and WAnT. This study demonstrated that the TST is a reliable measure, with moderate association to swimming performance, producing similar physiological responses compared to free swimming. Therefore, future research shoulSd focus on investigating the potential benefits of utilizing the TST as a regular assessment tool as a part of a competitive swimming training program to track adaptations and inform training decisions.

Cardiorespiratory performance during prolonged swimming tests with salmonids: a perspective on temperature effects and potential analytical pitfalls.

PubMed

Farrell, A P

2007-11-29

A prolonged swimming trial is the most common approach in studying steady-state changes in oxygen uptake, cardiac output and tissue oxygen extraction as a function of swimming speed in salmonids. The data generated by these sorts of studies are used here to support the idea that a maximum oxygen uptake is reached during a critical swimming speed test. Maximum oxygen uptake has a temperature optimum. Potential explanations are advanced to explain why maximum aerobic performance falls off at high temperature. The valuable information provided by critical swimming tests can be confounded by non-steady-state swimming behaviours, which typically occur with increasing frequency as salmonids approach fatigue. Two major concerns are noted. Foremost, measurements of oxygen uptake during swimming can considerably underestimate the true cost of transport near critical swimming speed, apparently in a temperature-dependent manner. Second, based on a comparison with voluntary swimming ascents in a raceway, forced swimming trials in a swim tunnel respirometer may underestimate critical swimming speed, possibly because fish in a swim tunnel respirometer are unable to sustain a ground speed.

Effects of co-treatment with mirtazapine and low doses of risperidone on immobility time in the forced swimming test in mice.

PubMed

Rogóż, Zofia

2010-01-01

The aim of the present study was to examine the effect of mirtazapine (MIR) and risperidone (an atypical antipsychotic drug), given separately or jointly, on immobility time in the forced swimming test in male C57BL/6J mice. Fluoxetine (FLU) was used as a reference drug. MIR (2.5, 5 and 10 mg/kg) and FLU (5 and 10 mg/kg), or risperidone in low doses (0.05 and 0.1 mg/kg) given alone did not change the immobility time of mice in the forced swimming test. Joint administration of MIR (5 and 10 mg/kg) or FLU (10 mg/kg) and risperidone (0.1 mg/kg) produced antidepressant-like activity in the forced swimming test. WAY100636 (a 5-HT(1A) receptor antagonist) inhibited, while yohimbine (an α(2)-adrenergic receptor antagonist) potentiated the antidepressant-like effect induced by co-administration of MIR and risperidone. Active behavior in that test did not reflect an increase in general activity, since combined administration of antidepressants and risperidone failed to enhance the locomotor activity of mice. The obtained results indicate that risperidone applied in a low dose enhances the antidepressant-like activity of MIR and that, among other mechanisms, 5-HT(1A)-, and α(2)-adrenergic receptors may play a role in this effect.

Swimming performance of young lake trout after chronic exposure to PCBs and DDE

USGS Publications Warehouse

Rottiers, Donald V.; Bergstedt, Roger A.

1981-01-01

Swimming performance was measured in fry of lake trout (Salvelinus namaycush) exposed to PCB's, DDE, and a combination of these two contaminants in both food and water at concentrations equal to, and 5 and 25 times higher than, levels found in Lake Michigan water and plankton. Fry were tested after about 50, 110, and 165 days of exposure. We measured swimming performance by forcing the fry to swim through a continuous series of incrementally increased velocities until the fish were exhausted. Although we observed significant differences in swimming performance between a few test groups, we detected no relation between swimming performance of the fry and exposure to PCB's or DDE, or both, at the concentrations tested. Inasmuch as swimming performance apparently was not affected by the levels of contamination by PCB's and DDE in Lake Michigan, impairment of swimming by these contaminants cannot account for the failure of lake trout reproduction in Lake Michigan.

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.

Effect of Different Stressors on Voluntary Ethanol Intake in Ethanol-Dependent and Nondependent C57BL/6J Mice

PubMed Central

Lopez, Marcelo F.; Anderson, Rachel I.; Becker, Howard C.

2016-01-01

Several animal models have evaluated the effect of stress on voluntary ethanol intake with mixed results. The experiments reported here examined the effects of different stressors on voluntary ethanol consumption in dependent and nondependent adult male C57BL/6J mice. In Experiment 1, restraint, forced swim, and social defeat stress procedures all tended to reduce ethanol intake in nondependent mice regardless of whether the stress experience occurred 1 h or 4 h prior to ethanol access. The reduction in ethanol consumption was most robust following restraint stress. Experiment 2 examined the effects of forced swim stress and social defeat stress on drinking in a dependence model that involved repeated cycles of chronic intermittent ethanol (CIE) exposure. Repeated exposure to forced swim stress prior to intervening test drinking periods that followed repeated cycles of CIE exposure further increased ethanol consumption in CIE-exposed mice while not altering intake in nondependent mice. In contrast, repeated exposure to the social defeat stressor in a similar manner reduced ethanol consumption in CIE-exposed mice while not altering drinking in nondependent mice. Results from Experiment 3 confirmed this selective effect of forced swim stress increasing ethanol consumption in mice with a history of CIE exposure, and also demonstrated that enhanced drinking is only observed when the forced swim stressor is administered during each test drinking week, but not if it is applied only during the final test week. Collectively, these studies point to a unique interaction between repeated stress experience and CIE exposure, and also suggest that such an effect depends on the nature of the stressor. Future studies will need to further explore the generalizability of these results, as well as mechanisms underlying the ability of forced swim stress to selectively further enhance ethanol consumption in dependent (CIE-exposed) mice but not alter intake in nondependent animals. PMID:26992696

Effect of different stressors on voluntary ethanol intake in ethanol-dependent and nondependent C57BL/6J mice.

PubMed

Lopez, Marcelo F; Anderson, Rachel I; Becker, Howard C

2016-03-01

Several animal models have evaluated the effect of stress on voluntary ethanol intake with mixed results. The experiments reported here examined the effects of different stressors on voluntary ethanol consumption in dependent and nondependent adult male C57BL/6J mice. In Experiment 1, restraint, forced swim, and social defeat stress procedures all tended to reduce ethanol intake in nondependent mice regardless of whether the stress experience occurred 1 h or 4 h prior to ethanol access. The reduction in ethanol consumption was most robust following restraint stress. Experiment 2 examined the effects of forced swim stress and social defeat stress on drinking in a dependence model that involved repeated cycles of chronic intermittent ethanol (CIE) exposure. Repeated exposure to forced swim stress prior to intervening test drinking periods that followed repeated cycles of CIE exposure further increased ethanol consumption in CIE-exposed mice while not altering intake in nondependent mice. In contrast, repeated exposure to the social defeat stressor in a similar manner reduced ethanol consumption in CIE-exposed mice while not altering drinking in nondependent mice. Results from Experiment 3 confirmed this selective effect of forced swim stress increasing ethanol consumption in mice with a history of CIE exposure, and also demonstrated that enhanced drinking is only observed when the forced swim stressor is administered during each test drinking week, but not if it is applied only during the final test week. Collectively, these studies point to a unique interaction between repeated stress experience and CIE exposure, and also suggest that such an effect depends on the nature of the stressor. Future studies will need to further explore the generalizability of these results, as well as mechanisms underlying the ability of forced swim stress to selectively further enhance ethanol consumption in dependent (CIE-exposed) mice but not alter intake in nondependent animals. Copyright © 2016 Elsevier Inc. All rights reserved.

[Unpredictable chronic mild stress effects on antidepressants activities in forced swim test].

PubMed

Kudryashov, N V; Kalinina, T S; Voronina, T A

2015-02-01

The experiments has been designed to study unpredictable chronic mild stress effect on anti-depressive activities of amitriptyline (10 mg/kg) and fluoxetine (20 mg/kg) in forced swim test in male outbred mice. It is shown that acute treatment with fluoxetine does not produce any antidepressant effects in mice following stress of 14 days while the sub-chronic injections of fluoxetine result in more deep depressive-like behavior. In 28 daily stressed mice, antidepressant effect of fluoxetine is observed independently of the injection rates. Amitriptyline demonstrates the antidepressant activity regardless of the duration of stress or administration scheduling, but at the same time the severity of anti-immobilization effect of amitriptyline in stressed mice is weaker in compare to non-stressed trails. Thus, the injection rates and duration of unpredictable mild chronic stress are the parameters that determine the efficiency of antidepressants in the mouse forced swimming test.

[A comparative study on behaviors of two depression models in rats induced by chronic forced swimming stress].

PubMed

Han, Ming-Fei; Gao, Dong; Sun, Xue-Li

2010-01-01

To compare the behaviors of rats with depressions induced by chronic forced swimming stress under two different conditions. Eighteen male rats were randomly divided into 3 groups, with 6 rats in each group. The rats in the control group (C group) were not forced into swimming, while the rats in the stress groups (S1 and S2) were forced to swim for 14 consecutive days. The rats in S1 group and S2 group swam for five minutes every morning, in water with (23 +/- 1) degree C, and (10 +/- 0.5) degree C in temperature, respectively. The weight gain, food intake, open-field test and saccharin solution test were observed on the seventh day and fourteenth day. On the seventh day following chronic swim stress, the rats in the S2 group had significant lower ratio in weight gain and food intake than the controls (P < 0.05). On the fourteenth day, the rats in the S2 group had significant lower ratio in weight gain (12.26 +/- 4.04)%, food intake (9.49 +/- 0.96)%, sucrose intake (28.63 +/- 3.51) g, and preference for saccharin solution (76.25 +/- 2.51)%, and less number of crossing (12.17 +/- 9.00) and times of rearing (3.17 +/- 3.60) than the controls (P < 0.05). The rats in the S1 group had significant lower ratio in weight gain and food intake than the controls on the seventh day following forced swimming. On the fourteenth day, the rats in the S1 group still had lower ratio in weight gain, but had higher ratio in food intake and preference for saccharin solution, and greater number of crossing than the controls. Chronic forced swimming at a lower temperature could induce depression better than at a higher temperature.

C1473G polymorphism in mouse tph2 gene is linked to tryptophan hydroxylase-2 activity in the brain, intermale aggression, and depressive-like behavior in the forced swim test.

PubMed

Osipova, Daria V; Kulikov, Alexander V; Popova, Nina K

2009-04-01

Tryptophan hydroxylase-2 (TPH2) is the rate-limiting enzyme of brain serotonin synthesis. The C1473G polymorphism in the mouse tryptophan hydroxylase-2 gene affects the enzyme's activity. In the present study, we investigated the linkage between the C1473G polymorphism, enzyme activity in the brain, and behavior in the forced swim, intermale aggression, and open field tests using mice of the C57BL/6 (C/C) and CC57BR/Mv (G/G) strains and the B6-1473C (C/C) and B6-1473G (G/G) lines created by three successive backcrossings on C57BL/6. Mice of the CC57BR/Mv strain had decreased brain enzyme activity, aggression intensity, and immobility in the forced swim test, but increased locomotor activity and time spent in the central part of the open field arena compared with animals of the C57BL/6 strain. Mice of the B6-1473G line homozygous for the 1473G allele had lower TPH2 activity in the brain, aggression intensity, and immobility time in the forced swim test compared with animals of the B6-1473C line homozygous for the 1473C allele. No differences were found between the B6-1473G and B6-1473C mice in locomotor activity and time spent in the central part of the arena in the open field test. Thus, the C1473G polymorphism is involved in the determination of TPH2 activity and is linked to aggression intensity and forced-swim immobility in mice. At the same time, the polymorphism does not affect locomotion and anxiety-related behavior in the open field test. The B6-1473C and B6-1473G mice represent a valuable experimental model for investigating molecular mechanisms of serotonin-related behavior.

Sex and age differences in the impact of the forced swimming test on the levels of steroid hormones.

PubMed

Martínez-Mota, Lucía; Ulloa, Rosa-Elena; Herrera-Pérez, Jaime; Chavira, Roberto; Fernández-Guasti, Alonso

2011-10-24

Compared with the adult disorder, depression in children exhibits differences in its neurobiology, particularly in the HPA axis regulation. The bases of such differences can be evaluated in animal models of depression. The objective of the present study was to determine age and sex differences of Wistar rats in the forced swimming test (FST). The influence of sex and age on corticosterone, estrogens and testosterone serum levels was also determined. Prepubertal rats showed immobility, swimming and climbing behaviors during the pre-test and test sessions. In addition, in the prepubertal animals, no sex differences were found during the pre-test and test sessions. Age comparisons indicated no differences in the female groups, however adult males exhibited more immobility and less swimming than young males, in both FST sessions. The young and female rats showed less immobility behavior and increased levels of estrogens after the FST. The present results indicate that the FST is an animal model suitable to evaluate depressive-like behaviors in prepubertal subjects and to explore behavioral changes related to neurodevelopment. Copyright © 2011 Elsevier Inc. All rights reserved.

Effect of fish oil and coconut fat supplementation on depressive-type behavior and corticosterone levels of prenatally stressed male rats.

PubMed

Borsonelo, Elizabethe Cristina; Suchecki, Deborah; Galduróz, José Carlos Fernandes

2011-04-18

Prenatal stress (PNS) during critical periods of brain development has been associated with numerous behavioral and/or mood disorders in later life. These outcomes may result from changes in the hypothalamic-pituitary-adrenal (HPA) axis activity, which, in turn, can be modulated by environmental factors, such as nutritional status. In this study, the adult male offspring of dams exposed to restraint stress during the last semester of pregnancy and fed different diets were evaluated for depressive-like behavior in the forced swimming test and for the corticosterone response to the test. Female Wistar rats were allocated to one of three groups: regular diet, diet supplemented with coconut fat or with fish oil, offered during pregnancy and lactation. When pregnancy was confirmed, they were distributed into control or stress groups. Stress consisted of restraint and bright light for 45 min, three times per day, in the last week of pregnancy. The body weight of the adult offspring submitted to PNS was lower than that of controls. In the forced swimming test, time of immobility was reduced and swimming was increased in PNS rats fed fish oil and plasma corticosterone levels immediately after the forced swimming test were lower in PNS rats fed regular diet than their control counterparts; this response was reduced in control rats whose mothers were fed fish oil and coconut fat. The present results indicate that coconut fat and fish oil influenced behavioral and hormonal responses to the forced swimming test in both control and PNS adult male rats. Copyright © 2011 Elsevier B.V. All rights reserved.

Antidepressant-like action of the hydromethanolic flower extract of Tagetes erecta L. in mice and its possible mechanism of action.

PubMed

Khulbe, Aarti; Pandey, Savita; Sah, Sangeeta Pilkhwal

2013-01-01

Tagetes erecta, the marigold, has commercial and ethnomedicinal use; however, reports concerning its efficacy for the treatment of depression are lacking. This study was carried out to elucidate the antidepressant effect of hydromethanolic flower extract of T. erecta. Hydromethanolic extract of flowers of Tagetes erecta was subjected to preliminary phytochemical screening. The extract (12.5, 25, and 50 mg/kg, i.p.) was evaluated for antidepressant effect using forced swim test in mice. The mechanism of antidepressant action was further examined using different drugs and imipramine was used as standard drug. T. erecta significantly inhibited the immobility period in forced swim test in mice P<0.05). T. erecta (25 mg/kg, i.p.) enhanced the anti-immobility effect of antidepressant drugs like imipramine, fluoxetine, and p-chlorophenylalanine, an inhibitor of serotonin synthesis significantly attenuated its antidepressant effect. The antidepressant effect of T. erecta in the forced swim test was prevented by pretreatment with L-arginine and sildenafil, whereas pretreatment of mice with nitric oxide synthase inhibitors potentiated the action. Pentazocine, a high-affinity sigma receptor agonist, produced synergism with effective dose of T. erecta while progesterone, a sigma receptor antagonist, reversed the antidepressant effect of T. erecta. However, the locomotor activity was not affected at tested doses. Serotonergic, nitrergic pathway, and sigma receptors are possibly involved in mediating antidepressant action of T. erecta in mouse forced swim test.

Desipramine and citalopram attenuate pretest swim-induced increases in prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis and the lateral division of the central nucleus of the amygdala in the forced swimming test.

PubMed

Chung, Sung; Kim, Hee Jeong; Kim, Hyun Ju; Choi, Sun Hye; Cho, Jin Hee; Cho, Yun Ha; Kim, Dong-Hoon; Shin, Kyung Ho

2014-10-01

Dynorphin in the nucleus accumbens shell plays an important role in antidepressant-like effect in the forced swimming test (FST), but it is unclear whether desipramine and citalopram treatments alter prodynorphin levels in other brain areas. To explore this possibility, we injected mice with desipramine and citalopram 0.5, 19, and 23 h after a 15-min pretest swim and observed changes in prodynorphin expression before the test swim, which was conducted 24 h after the pretest swim. The pretest swim increased prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis (dBNST) and lateral division of the central nucleus of the amygdala (CeL). This increase in prodynorphin immunoreactivity in the dBNST and CeL was blocked by desipramine and citalopram treatments. Similar changes in prodynorphin mRNA levels were observed in the dBNST and CeL, but these changes did not reach significance. To understand the underlying mechanism, we assessed changes in phosphorylated CREB at Ser(133) (pCREB) immunoreactivity in the dBNST and central nucleus of the amygdala (CeA). Treatment with citalopram but not desipramine after the pretest swim significantly increased pCREB immunoreactivity only in the dBNST. These results suggest that regulation of prodynorphin in the dBNST and CeL before the test swim may be involved in the antidepressant-like effect of desipramine and citalopram in the FST and suggest that changes in pCREB immunoreactivity in these areas may not play an important role in the regulation of prodynorphin in the dBNST and CeA. Copyright © 2014 Elsevier Ltd. All rights reserved.

Level of Interleukins IL-6 and IL-15 in Blood Plasma of Mice after Forced Swimming Test.

PubMed

Kapilevich, L V; Kironenko, T A; Zakharova, A N; Kabachkova, A V; Orlov, S N

2017-05-01

We measured the concentrations of IL-6 and IL-15 in blood plasma of mice at different terms after forced swimming, taking into account exercise intensity and preliminary training. It was shown that training was an important factor affecting blood plasma level of IL both at rest and after single forced swimming: in trained animals, the concentration of both myokines increased immediately after swimming, while in untrained animals, this increase was observed only after 5 h. Changes in cytokine production against the background of training can be associated with various factors, including neuroendocrine mechanisms, stress, modification of intracellular signaling, as well as reorganization of transcriptional mechanisms in muscle fibers. The most important factor is shift in the ratio of monovalent cations (sodium and potassium) in the cytoplasm.

Mechanism of synergistic action following co-treatment with pramipexole and fluoxetine or sertraline in the forced swimming test in rats.

PubMed

Rogóz, Zofia; Skuza, Grazyna

2006-01-01

The aim of the present study was to examine the effect of combined treatment of male Wistar rats with pramipexole and fluoxetine or sertraline in the forced swimming test. The obtained results showed that co-treatment with pramipexole (0.1 mg/kg) and fluoxetine (10 mg/kg) or sertraline (5 mg/kg) (in doses inactive per se) exhibited antidepressant-like activity in the forced swimming test. Sulpiride (a dopamine D(2/3) receptor antagonist) and WAY 100635 (a 5-HT(1A) receptor antagonist), either being ineffective in the forced swimming test, inhibited the antidepressant-like effect induced by co-administration of pramipexole and fluoxetine or sertraline. However, SCH 23390 (a dopamine D(1) receptor antagonist) only partly did not alter the effect of pramipexole given jointly with antidepressant drugs; on the other hand, S 33084 (a dopamine D(3) receptor antagonist) only partly decreased (in a statistically insignificant manner) that effect. Moreover, progesterone and BD 1047 (a sigma(1) receptor antagonist) counteracted the antidepressant-like effect induced by co-administration of pramipexole and sertraline (but not pramipexole and fluoxetine). In that test, active behavior did not reflect the increases in general activity, since combined administration of pramipexole and fluoxetine or sertraline failed to enhance the locomotor activity of rats. None of the tested drugs (SCH 23390, sulpiride, S 33084, WAY 100635, BD 1047 and progesterone) - alone or in combination with pramipexole and fluoxetine or sertraline - changed locomotor activity. The results described in the present paper indicate that co-administration of pramipexole and fluoxetine or sertraline may induce a more pronounced antidepressive activity than does treatment with pramipexole alone, and that in addition to other mechanisms, dopamine D(2/3) and 5-HT(1A) receptors may contribute to the antidepressant-like activity of pramipexole and fluoxetine or sertraline in the forced swimming test in rats. Moreover, sigma(1) receptors may constitute one of the possible mechanisms by which co-administration of pramipexole and sertraline induces antidepressant-like activity in that test.

Repeated forced swimming impairs prepulse inhibition and alters brain-derived neurotrophic factor and astroglial parameters in rats.

PubMed

Borsoi, Milene; Antonio, Camila Boque; Müller, Liz Girardi; Viana, Alice Fialho; Hertzfeldt, Vivian; Lunardi, Paula Santana; Zanotto, Caroline; Nardin, Patrícia; Ravazzolo, Ana Paula; Rates, Stela Maris Kuze; Gonçalves, Carlos-Alberto

2015-01-01

Glutamate perturbations and altered neurotrophin levels have been strongly associated with the neurobiology of neuropsychiatric disorders. Environmental stress is a risk factor for mood disorders, disrupting glutamatergic activity in astrocytes in addition to cognitive behaviours. Despite the negative impact of stress-induced neuropsychiatric disorders on public health, the molecular mechanisms underlying the response of the brain to stress has yet to be fully elucidated. Exposure to repeated swimming has proven useful for evaluating the loss of cognitive function after pharmacological and behavioural interventions, but its effect on glutamate function has yet to be fully explored. In the present study, rats previously exposed to repeated forced swimming were evaluated using the novel object recognition test, object location test and prepulse inhibition (PPI) test. In addition, quantification of brain-derived neurotrophic factor (BDNF) mRNA expression and protein levels, glutamate uptake, glutathione, S100B, GluN1 subunit of N-methyl-D-aspartate receptor and calmodulin were evaluated in the frontal cortex and hippocampus after various swimming time points. We found that swimming stress selectively impaired PPI but did not affect memory recognition. Swimming stress altered the frontal cortical and hippocampal BDNF expression and the activity of hippocampal astrocytes by reducing hippocampal glutamate uptake and enhancing glutathione content in a time-dependent manner. In conclusion, these data support the assumption that astrocytes may regulate the activity of brain structures related to cognition in a manner that alters complex behaviours. Moreover, they provide new insight regarding the dynamics immediately after an aversive experience, such as after behavioural despair induction, and suggest that forced swimming can be employed to study altered glutamatergic activity and PPI disruption in rodents. Copyright © 2014. Published by Elsevier Inc.

Antidepressant-like effects of the acute and chronic administration of nicotine in the rat forced swimming test and its interaction with fluoxetine [correction of flouxetine].

PubMed

Vázquez-Palacios, G; Bonilla-Jaime, H; Velázquez-Moctezuma, J

2004-05-01

An antidepressant action of nicotine (NIC) has recently been suggested. Flouxetine, a selective serotonin reuptake inhibitor, is currently the most widely used antidepressant. In the present study, we analyzed the effects of the administration of NIC, fluoxetine (FLX), and the combination of both drugs given acutely, subchronically, and chronically as well as 7 days after chronic administration of these drugs on the forced swim test. Results showed that NIC induced a significant reduction of the time in immobility during the forced swim test (antidepressant effect), with a concomitant increase in swimming activity (serotonergic activation), after acute administration. These effects remain the same after subchronic and chronic administration. FLX failed to induce any effect after acute administration but did induce a significant decrease of immobility and an increase of swimming after subchronic administration. The effect of the chronic administration was significantly larger compared to subchronic administration. The combination of both drugs induced a larger effect than that observed after a single administration but only after subchronic treatment. No effect was observed after the end of the 7-day treatments. Data suggest that NIC has an antidepressant action that is expressed faster than FLX but remains the same later. Thus, cholinergic-serotonergic interactions could play an important role in the treatment of depression.

Desipramine restricts estral cycle oscillations in swimming.

PubMed

Contreras, C M; Martínez-Mota, L; Saavedra, M

1998-10-01

1. Desipramine (DMI) is a tricyclic antidepressant which reduces the immobility in rats forced to swim; however, it is unknown whether estral cycle phases impinge on DMI actions on immobility in daily swimming tests during several weeks. 2. In female wistar rats, vaginal smears taken before testing defined four estral phases. Afterwards, the authors assessed the latency for the first period of immobility in five-min forced swim tests practiced on 21-day DMI (DMI group), 21-day washout saline given after a 21-day DMI treatment (washout-saline group), or non-treated rats (control group). 3. We observed a longer latency for the first period of immobility in proestrus-estrus from the control and washout-saline groups. The 21-day treatment with DMI (2.1 mg/kg i.p., once a day) significantly (p < 0.001) increased the latency by about 160% from control regardless of the estral cycle phase. 4. It is concluded that proestrus-estrus relates to increased struggling behavior. DMI enhances struggling behavior independently of hormonal state.

Increased water temperature renders single-housed C57BL/6J mice susceptible to antidepressant treatment in the forced swim test.

PubMed

Bächli, Heidi; Steiner, Michel A; Habersetzer, Ursula; Wotjak, Carsten T

2008-02-11

To investigate genotype x environment interactions in the forced swim test, we tested the influence of water temperature (20 degrees C, 25 degrees C, 30 degrees C) on floating behaviour in single-housed male C57BL/6J and BALB/c mice. We observed a contrasting relationship between floating and water temperature between the two strains, with C57BL/6J floating more and BALB/c floating less with increasing water temperature, independent of the lightening conditions and the time point of testing during the animals' circadian rhythm. Both strains showed an inverse relationship between plasma corticosterone concentration and water temperature, indicating that the differences in stress coping are unrelated to different perception of the aversive encounter. Treatment with desipramine (20mg/kg, i.p.) caused a reduction in immobility time in C57BL/6J mice if the animals were tested at 30 degrees C water temperature, with no effect at 25 degrees C and no effects on forced swim stress-induced corticosterone secretion. The same treatment failed to affect floating behaviour in BALB/c at any temperature, but caused a decrease in plasma corticosterone levels. Taken together we demonstrate that an increase in water temperature in the forced swim test exerts opposite effects on floating behaviour in C57BL/6J and BALB/c and renders single-housed C57BL/6J mice, but not BALB/c mice, susceptible to antidepressant-like behavioral effects of desipramine.

Adenosine A2A receptors and depression.

PubMed

El Yacoubi, Malika; Costentin, Jean; Vaugeois, Jean-Marie

2003-12-09

Adenosine and its analogues have been shown to induce "behavioral despair" in animal models believed to be relevant to depression. Recent data have shown that selective adenosine A2A receptor antagonists (e.g., SCH 58261, ZM241385, and KW6002) or genetic inactivation of the receptor was effective in reversing signs of behavioral despair in the tail suspension and forced swim tests, two screening procedures predictive of antidepressant activity. A2A antagonists were active in the tail suspension test using either mice previously screened for having high immobility scores or mice that were selectively bred for their spontaneous "helplessness" in this test. At stimulant doses, caffeine, a nonselective A1/A2A receptor antagonist, was effective in the forced swim test. The authors have hypothesized that the antidepressant-like effect of selective A2A antagonists is linked to an interaction with dopaminergic transmission, possibly in the frontal cortex. In support of this idea, administration of the dopamine D2 receptor antagonist haloperidol prevented antidepressant-like effects elicited by SCH 58261 in the forced swim test (putatively involving cortex), whereas it had no effect on stimulant motor effects of SCH 58261 (putatively linked to ventral striatum). The interaction profile of caffeine with haloperidol differed markedly from that of SCH 58261 in the forced swim and motor activity tests. Therefore, a clear-cut antidepressant-like effect could not be ascribed to caffeine. In conclusion, available data support the proposition that a selective blockade of the adenosine A2A receptor may be an interesting target for the development of effective antidepressant agents.

Fluoxetine Alleviates Behavioral Depression while Decreasing Acetylcholine Release in the Nucleus Accumbens Shell

PubMed Central

Chau, David T; Rada, Pedro V; Kim, Kay; Kosloff, Rebecca A; Hoebel, Bartley G

2011-01-01

Selective serotonin reuptake inhibitors, such as fluoxetine, have demonstrated the ability to alleviate behavioral depression in the forced swim test; however, the sites and mechanisms of their actions remain to be further elucidated. Previous studies have suggested that behavioral depression in the swim test is mediated in part by acetylcholine (ACh) stimulating the cholinergic M1 receptors in the nucleus accumbens (NAc) shell. The current study tested whether acute, local, and chronic, subcutaneous fluoxetine treatments increase escape motivation during the swim test while simultaneously lowering extracellular ACh in the NAc shell. Experiment 1: Fluoxetine (1.0 mM) infused unilaterally in the NAc shell for 40 min reduced extracellular ACh while simultaneously increasing swimming time. Experiment 2: Fluoxetine (0.2, 0.5, and 0.75 mM) infused bilaterally in the NAc shell on day 3 dose-dependently decreased immobility and increased the total escape attempts (swimming and climbing) compared with Ringer given on day 2. Experiment 3: Fluoxetine (0.5 mM) infused bilaterally in the NAc for 40 min did not affect activities in an open field. Experiment 4: Chronic systemic fluoxetine treatment decreased immobility scores and increased total escape attempt scores compared with control saline treatment. In all, 14 days after the initial swim test, basal extracellular ACh in the shell was still elevated in the saline-treated group, but not in the fluoxetine-treated group. In summary, these data suggest that one of the potential mechanisms by which fluoxetine alleviates behavioral depression in the forced swim test may be to suppress cholinergic activities in the NAc shell. PMID:21525864

Tipepidine, a non-narcotic antitussive, exerts an antidepressant-like effect in the forced swimming test in adrenocorticotropic hormone-treated rats.

PubMed

Kawaura, Kazuaki; Ogata, Yukino; Honda, Sokichi; Soeda, Fumio; Shirasaki, Tetsuya; Takahama, Kazuo

2016-04-01

We investigated whether tipepidine exerts an antidepressant-like effect in the forced swimming test in adrenocorticotropic hormone (ACTH)-treated rats, which is known as a treatment-resistant depression model, and we studied the pharmacological mechanisms of the effects of tipepidine. Male Wistar rats (5-7 weeks old) were used in this study. Tipepidine (20 and 40 mg/kg, i.p.) decreased the immobility time in the forced swimming test in ACTH-treated rats. The anti-immobility effect of tipepidine was blocked by a catecholamine-depleting agent, alpha-methyl-p-tyrosine (300 mg/kg, s.c.), but not by a serotonin-depleting agent, p-chlorophenylalanine. The anti-immobility effect of tipepidine was also blocked by a dopamine D1 receptor antagonist, SCH23390 (0.02 mg/kg, s.c.) and an adrenaline α2 receptor antagonist, yohimbine (2 mg/kg, i.p.). In microdialysis technique, tipepidine (40 mg/kg, i.p.) increased the extracellular dopamine level of the nucleus accumbens (NAc) in ACTH-treated rats. These results suggest that tipepidine exerts an antidepressant-like effect in the forced swimming test in ACTH-treated rats, and that the effect of tipepidine is mediated by the stimulation of dopamine D1 receptors and adrenaline α2 receptors. The results also suggest that an increase in the extracellular dopamine level in the NAc may be involved in the antidepressant-like effect of tipepidine in ACTH-treated rats. Copyright © 2016. Published by Elsevier B.V.

Effect of Polysaccharide from Cordyceps militaris (Ascomycetes) on Physical Fatigue Induced by Forced Swimming.

PubMed

Xu, Yan-Feng

2016-01-01

Cordyceps militaris is the one of the most important medicinal mushrooms, widely used in East Asian countries. Polysaccharide is considered to be the principal active component in C. militaris and has a wide range of biological and pharmacological properties. This study was undertaken to investigate the effect of polysaccharide from C. militaris (PCM) on physical fatigue induced in animals through a forced swimming test. The mice were divided into 4 groups receiving 28 days' treatment with drinking water (exercise control) or low-, medium-, and high-dose PCM (40, 80, and 160 mg/kg/day, respectively). After 28 days, the mice were subjected to the forced swimming test; the exhaustive swimming time was measured and fatigue-related biochemical parameters, including serum lactic acid, urea nitrogen, creatine kinase, alanine aminotransferase, aspartate aminotransferase, superoxide dismutase, glutathi- one peroxidase, catalase, malondialdehyde, liver glycogen, and muscle glycogen, were analyzed. The results showed that PCM could significantly prolong the exhaustive swimming time of mice; decrease concentrations of serum lactic acid, urea nitrogen, creatine kinase, aspartate aminotransferase, alanine aminotransferase, and malondialdehyde; and increase liver and muscle glycogen contents and the concentrations of serum superoxide dismutase, glutathione per- oxidase, and catalase. The data suggest that PCM has an antifatigue effect, and it might become a new functional food or medicine for fatigue resistance.

Antioxidant and Antifatigue Properties of the Aqueous Extract of Moringa oleifera in Rats Subjected to Forced Swimming Endurance Test.

PubMed

Lamou, Bonoy; Taiwe, Germain Sotoing; Hamadou, André; Abene; Houlray, Justin; Atour, Mahamat Mey; Tan, Paul Vernyuy

2016-01-01

The effects of the aqueous extract of Moringa oleifera on swimming performance and related biochemical parameters were investigated in male Wistar rats (130-132 g). Four groups of rats (16 per group) were fed a standard laboratory diet and given distilled water, 100, 200, or 400 mg/kg of extract, respectively, for 28 days. On day 28, 8 rats from each group were subjected to the forced swimming test with tail load (10% of body weight). The remaining 8 rats per group were subjected to the 90-minute free swim. Maximum swimming time, glycemia, lactamia, uremia, triglyceridemia, hepatic and muscle glycogen, hematological parameters, and oxidative stress parameters (superoxide dismutase, catalase, reduced glutathione, and malondialdehyde) were measured. Results. M. oleifera extract increased maximum swimming time, blood hemoglobin, blood glucose, and hepatic and muscle glycogen reserves. The extract also increased the activity of antioxidant enzymes and decreased the blood concentrations of malondialdehyde. Furthermore, it decreased blood concentrations of lactate, triglycerides, and urea. In conclusion, the antifatigue properties of M. oleifera extract are demonstrated by its ability to improve body energy stores and tissue antioxidant capacity and to reduce the tissue build-up of lactic acid.

Antidepressant behavioral effects of duloxetine and fluoxetine in the rat forced swimming test.

PubMed

Ciulla, Leandro; Menezes, Honório Sampaio; Bueno, Bárbara Beatriz Moreira; Schuh, Alexandre; Alves, Rafael José Vargas; Abegg, Milena Pacheco

2007-01-01

To compare the effects of the antidepressant drugs duloxetine and fluoxetine on depressive behaviors in rodents. Eighteen male Wistar rats were given systemic injections of duloxetine, fluoxetine, or saline prior to a Forced Swimming Test (FST). Immobility and number of stops were measured. Rats given injections of fluoxetine displayed significantly less immobility (p = 0.02) and fewer stops than the control group (p = 0.003). Duloxetine significantly reduced the number of stops (p = 0.003), but did not effect immobility (p = 0.48). Duloxetine and fluoxetine reduced depressive behaviors in the Forced FST. However, our findings suggest that fluoxetine is more effective than duloxetine.

Acute reversible inactivation of the bed nucleus of stria terminalis induces antidepressant-like effect in the rat forced swimming test

PubMed Central

2010-01-01

Background The bed nucleus of stria terminalis (BNST) is a limbic forebrain structure involved in hypothalamo-pituitary-adrenal axis regulation and stress adaptation. Inappropriate adaptation to stress is thought to compromise the organism's coping mechanisms, which have been implicated in the neurobiology of depression. However, the studies aimed at investigating BNST involvement in depression pathophysiology have yielded contradictory results. Therefore, the objective of the present study was to investigate the effects of temporary acute inactivation of synaptic transmission in the BNST by local microinjection of cobalt chloride (CoCl2) in rats subjected to the forced swimming test (FST). Methods Rats implanted with cannulae aimed at the BNST were submitted to 15 min of forced swimming (pretest). Twenty-four hours later immobility time was registered in a new 5 min forced swimming session (test). Independent groups of rats received bilateral microinjections of CoCl2 (1 mM/100 nL) before or immediately after pretest or before the test session. Additional groups received the same treatment and were submitted to the open field test to control for unspecific effects on locomotor behavior. Results CoCl2 injection into the BNST before either the pretest or test sessions reduced immobility in the FST, suggesting an antidepressant-like effect. No significant effect of CoCl2 was observed when it was injected into the BNST immediately after pretest. In addition, no effect of BNST inactivation was observed in the open field test. Conclusion These results suggest that acute reversible inactivation of synaptic transmission in the BNST facilitates adaptation to stress and induces antidepressant-like effects. PMID:20515458

Effects of combined administration of 5-HT1A and/or 5-HT1B receptor antagonists and paroxetine or fluoxetine in the forced swimming test in rats.

PubMed

Tatarczyńska, Ewa; Kłodzińska, Aleksandra; Chojnacka-Wójcik, Ewa

2002-01-01

Clinical data suggest that coadministration of pindolol, a 5-HT1A/5-HT1B/beta-adrenoceptor antagonist, and selective serotonin reuptake inhibitors (SSRIs) may shorten the time of onset of a clinical action and may increase beneficial effects of the therapy of drug-resistant depression. Effects of combined administration of SSRIs and 5-HT receptor ligands are currently evaluated in animal models for the detection of an antidepressant-like activity; however, the obtained results turned out to be inconsistent. The aim of the present study was to investigate effects of a 5-HT1A antagonist (WAY 100635), 5-HT1B antagonists (SB 216641 and GR 127935) or pindolol, given in combination with paroxetine or fluoxetine (SSRIs), in the forced swimming test in rats (Porsolt test). When given alone, paroxetine (10 and 20 mg/kg), fluoxetine (10 and 20 mg/kg), WAY 100635 (0.1 and 1 mg/kg), SB 216641 (2 mg/kg), GR 127935 (10 and 20 mg/kg) and pindolol (4 and 8 mg/kg) did not shorten the immobility time of rats in that test. Interestingly, SB 216641 administered alone at a dose of 4 mg/kg produced a significant reduction of the immobility time in that test. A combination of paroxetine (20 mg/kg) and WAY 100635 or pindolol failed to reveal a significant interaction; on the other hand, when paroxetine was given jointly with SB 216641 (2 mg/kg) or GR 127935 (10 and 20 mg/kg), that combination showed a significant antiimmobility action in the forced swimming test in rats. The active behaviors in that test did not reflect increased general activity because combined administration of both the 5-HT1B antagonists and paroxetine failed to alter the locomotor activity of rats, measured in the open field test. Coadministration of fluoxetine and all the antagonists used did not affect the behavior of rats in the forced swimming test. The obtained results seem to indicate that blockade of 5-HT1B receptors, but not 5-HT1A ones, can facilitate the antidepressant-like effect of paroxetine in the forced swimming test in rats. No interaction was observed between fluoxetine and 5-HT1A/5-HT1B receptor antagonists.

Combined strength and endurance training in competitive swimmers.

PubMed

Aspenes, Stian; Kjendlie, Per-Ludvik; Hoff, Jan; Helgerud, Jan

2009-01-01

A combined intervention of strength and endurance training is common practice in elite swimming training, but the scientific evidence is scarce. The influences between strength and endurance training have been investigated in other sports but the findings are scattered. Some state the interventions are negative to each other, some state there is no negative relationship and some find bisected and supplementary benefits from the combination when training is applied appropriately. The aim of this study was to investigate the impact of a combined intervention among competitive swimmers. 20 subjects assigned to a training intervention group (n = 11) or a control group (n = 9) from two different teams completed the study. Anthropometrical data, tethered swimming force, land strength, performance in 50m, 100m and 400m, work economy, peak oxygen uptake, stroke length and stroke rate were investigated in all subjects at pre- and post-test. A combined intervention of maximal strength and high aerobic intensity interval endurance training 2 sessions per week over 11 weeks in addition to regular training were used, while the control group continued regular practice with their respective teams. The intervention group improved land strength, tethered swimming force and 400m freestyle performance more than the control group. The improvement of the 400m was correlated with the improvement of tethered swimming force in the female part of the intervention group. No change occurred in stroke length, stroke rate, performance in 50m or 100m, swimming economy or peak oxygen uptake during swimming. Two weekly dry-land strength training sessions for 11 weeks increase tethered swimming force in competitive swimmers. This increment further improves middle distance swimming performance. 2 weekly sessions of high- intensity interval training does not improve peak oxygen uptake compared with other competitive swimmers. Key pointsTwo weekly sessions of dry land strength training improves the swimming force.Two weekly sessions of high-intensity endurance training did not cause improved endurance capacity.It may seem that dry land strength training can improve middle distance performance.

Antidepressant-like activity of liposomal formulation containing nimodipine treatment in the tail suspension test, forced swim test and MAOB activity in mice.

PubMed

Moreno, Lina Clara Gayoso E Almendra Ibiapina; Rolim, Hercília Maria Lins; Freitas, Rivelilson Mendes; Santos-Magalhães, Nereide Stela

2016-09-01

Previous studies have shown that intracellular calcium ion dysfunction may be an etiological factor in affective illness. Nimodipine (NMD) is a Ca(2+) channel blocker that has been extensively investigated for therapy of central nervous system (CNS) disorders. In this work, we have evaluated the antidepressant-like activity of nimodipine encapsulated into liposomes (NMD-Lipo) in mice through tail suspension and forced swim assays, as well as MAOB activity. During the tail suspension test, the administration of NMD-Lipo at 0.1, 1 and 10mg/kg was able to promote a reduction in the immobility time of animals greater than the positive control (imipramine). In the forced swim test, the immobility time of mice treated with NMD-Lipo was reduced. This reduction was significantly greater than that found in the animals treated with imipramine and paroxetine. This may suggest that NMD-Lipo provides more antidepressant-like activity than in positive controls. The groups that received a combination of liposomal NMD and antidepressant drugs showed lower immobility time than the groups, which were treated only with imipramine or paroxetine. The mice treated with the combination of NMD-Lipo and reserpine presented an increase in the time of immobility compared with animals treated only with NMD-Lipo. There was a significant decrease in MAOB activity in animals treated with NMD-Lipo compared with untreated animals. The results of the tail suspension test, forced swim test and MAOB activity suggested that the antidepressant activity of NMD-Lipo may be related to an increase in the cerebral monoamine concentrations. Copyright © 2016 Elsevier B.V. All rights reserved.

Chronic mild stress increases alcohol intake in mice with low dopamine D2 receptor levels.

PubMed

Delis, Foteini; Thanos, Panayotis K; Rombola, Christina; Rosko, Lauren; Grandy, David; Wang, Gene-Jack; Volkow, Nora D

2013-02-01

Alcohol use disorders emerge from a complex interaction between environmental and genetic factors. Stress and dopamine D2 receptor levels (DRD2) have been shown to play a central role in alcoholism. To better understand the interactions between DRD2 and stress in ethanol intake behavior, we subjected Drd2 wild-type (+/+), heterozygous (+/-), and knockout (-/-) mice to 4 weeks of chronic mild stress (CMS) and to an ethanol two-bottle choice during CMS weeks 2-4. Prior to and at the end of the experiment, the animals were tested in the forced swim and open field tests. We measured ethanol intake and preference, immobility in the force swim test, and activity in the open field. We show that under no CMS, Drd2+/- and Drd2-/- mice had lower ethanol intake and preference compared with Drd2+/+. Exposure to CMS decreased ethanol intake and preference in Drd2+/+ and increased them in Drd2+/- and Drd2-/- mice. At baseline, Drd2+/- and Drd2-/- mice had significantly lower activity in the open field than Drd2+/+, whereas no genotype differences were observed in the forced swim test. Exposure to CMS increased immobility during the forced swim test in Drd2+/- mice, but not in Drd2+/+ or Drd2-/- mice, and ethanol intake reversed this behavior. No changes were observed in open field test measures. These findings suggest that in the presence of a stressful environment, low DRD2 levels are associated with increased ethanol intake and preference and that under this condition, increased ethanol consumption could be used as a strategy to alleviate negative mood. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Ontogeny and adolescent alcohol exposure in Wistar rats: open field conflict, light/dark box and forced swim test

PubMed Central

Desikan, Anita; Wills, Derek N.; Ehlers, Cindy L.

2014-01-01

Epidemiological studies have demonstrated that heavy drinking and alcohol abuse and dependence peak during the transition between late adolescence and early adulthood. Studies in animal models have demonstrated that alcohol exposure during adolescence can cause a modification in some aspects of behavioral development, causing the “adolescent phenotype” to be retained into adulthood. However, the “adolescent phenotype” has not been studied for a number of behavioral tests. The objective of the present study was to investigate the ontogeny of behaviors over adolescence/young adulthood in the light/dark box, open field conflict and forced swim test in male Wistar rats. These data were compared to previously published data from rats that received intermittent alcohol vapor exposure during adolescence (AIE) to test whether they retained the “adolescent phenotype” in these behavioral tests. Three age groups of rats were tested (post-natal day (PD) 34–42; PD55-63; PD69-77). In the light/dark box test, younger rats escaped the light box faster than older adults, whereas AIE rats returned to the light box faster and exhibited more rears in the light than controls. In the open field conflict test, both younger and AIE rats had shorter times to first enter the center, spent more time in the center of the field, were closer to the food, and consumed more food than controls. In the forced swim test no clear developmental pattern emerged. The results of the light/dark box and the forced swim test do not support the hypothesis that adolescent ethanol vapor exposure can “lock-in” all adolescent phenotypes. However, data from the open field conflict test suggest that the adolescent and the AIE rats both engaged in more “disinhibited” and food motivated behaviors. These data suggest that, in some behavioral tests, AIE may result in a similar form of behavioral disinhibition to what is seen in adolescence. PMID:24785000

Ontogeny and adolescent alcohol exposure in Wistar rats: open field conflict, light/dark box and forced swim test.

PubMed

Desikan, Anita; Wills, Derek N; Ehlers, Cindy L

2014-07-01

Epidemiological studies have demonstrated that heavy drinking and alcohol abuse and dependence peak during the transition between late adolescence and early adulthood. Studies in animal models have demonstrated that alcohol exposure during adolescence can cause a modification in some aspects of behavioral development, causing the "adolescent phenotype" to be retained into adulthood. However, the "adolescent phenotype" has not been studied for a number of behavioral tests. The objective of the present study was to investigate the ontogeny of behaviors over adolescence/young adulthood in the light/dark box, open field conflict and forced swim test in male Wistar rats. These data were compared to previously published data from rats that received intermittent alcohol vapor exposure during adolescence (AIE) to test whether they retained the "adolescent phenotype" in these behavioral tests. Three age groups of rats were tested (post-natal day (PD) 34-42; PD55-63; PD69-77). In the light/dark box test, younger rats escaped the light box faster than older adults, whereas AIE rats returned to the light box faster and exhibited more rears in the light than controls. In the open field conflict test, both younger and AIE rats had shorter times to first enter the center, spent more time in the center of the field, were closer to the food, and consumed more food than controls. In the forced swim test no clear developmental pattern emerged. The results of the light/dark box and the forced swim test do not support the hypothesis that adolescent ethanol vapor exposure can "lock-in" all adolescent phenotypes. However, data from the open field conflict test suggest that the adolescent and the AIE rats both engaged in more "disinhibited" and food motivated behaviors. These data suggest that, in some behavioral tests, AIE may result in a similar form of behavioral disinhibition to what is seen in adolescence. Copyright © 2014. Published by Elsevier Inc.

Antidepressant-like effect of harmane and other beta-carbolines in the mouse forced swim test.

PubMed

Farzin, Davood; Mansouri, Nazanin

2006-07-01

The purpose of the present study was to determine the effects of harmane, norharmane and harmine on the immobility time in the mouse forced swim test (FST) - an animal model of depression. After 30 min of the beta-carbolines injections, mice were placed individually in a vertical glass cylinder (height, 25 cm; diameter, 12 cm) containing water about 15 cm deep at 22+/-1 degrees C and forced to swim. Treatment of animals with harmane (5-15 mg/kg, i.p.), norharmane (2.5-10 mg/kg, i.p.) and harmine (5-15 mg/kg, i.p.) reduced dose-dependently the time of immobility. Their antidepressant-like effects were not affected by pretreatment with reserpine at the dose of 5 mg/kg, i.p., 18 h before the test, which did not modify the immobility time. Conversely, when flumazenil (5 mg/kg, i.p.) was administered 30 min before the test, it was able to antagonize completely the antidepressant-like effects of harmane, norharmane and harmine. It was concluded that harmane, norharmane and harmine reduce the immobility time in this test, suggesting an antidepressant-like effect, via an inverse-agonistic mechanism located in the benzodiazepine receptors.

Antidepressant-like effect of m-trifluoromethyl-diphenyl diselenide in the mouse forced swimming test involves opioid and serotonergic systems.

PubMed

Brüning, César Augusto; Souza, Ana Cristina Guerra; Gai, Bibiana Mozzaquatro; Zeni, Gilson; Nogueira, Cristina Wayne

2011-05-11

Serotonergic and opioid systems have been implicated in major depression and in the action mechanism of antidepressants. The organoselenium compound m-trifluoromethyl-diphenyl diselenide (m-CF(3)-PhSe)(2) shows antioxidant and anxiolytic activities and is a selective inhibitor of monoamine oxidase A activity. The present study was designed to investigate the antidepressant-like effect of (m-CF(3)-PhSe)(2) in female mice, employing the forced swimming test. The involvement of the serotonergic and opioid systems in the antidepressant-like effect of (m-CF(3)-PhSe)(2) was appraised. (m-CF(3)-PhSe)(2) at doses of 50 and 100mg/kg (p.o.) exhibited antidepressant-like action in the forced swimming test. The effect of (m-CF(3)-PhSe)(2) (50mg/kg p.o.) was prevented by pretreatment of mice with WAY100635 (0.1mg/kg, s.c. a selective 5-HT(1A) receptor antagonist), ritanserin (4 mg/kg, i.p., a non-selective 5HT(2A/2C) receptor antagonist), ondansetron (1mg/kg, i.p., a selective 5-HT(3) receptor antagonist) and naloxone (1mg/kg, i.p., a non-selective antagonist of opioid receptors). These results suggest that (m-CF(3)-PhSe)(2) produced an antidepressant-like effect in the mouse forced swimming test and this effect seems most likely to be mediated through an interaction with serotonergic and opioid systems. Copyright © 2011 Elsevier B.V. All rights reserved.

Noradrenergic neurotransmission within the bed nucleus of the stria terminalis modulates the retention of immobility in the rat forced swimming test.

PubMed

Nagai, Michelly M; Gomes, Felipe V; Crestani, Carlos C; Resstel, Leonardo B M; Joca, Sâmia R L

2013-06-01

The bed nucleus of the stria terminalis (BNST) is a limbic structure that has a direct influence on the autonomic, neuroendocrine, and behavioral responses to stress. It was recently reported that reversible inactivation of synaptic transmission within this structure causes antidepressant-like effects, indicating that activation of the BNST during stressful situations would facilitate the development of behavioral changes related to the neurobiology of depression. Moreover, noradrenergic neurotransmission is abundant in the BNST and has an important role in the regulation of emotional processes related to the stress response. Thus, this study aimed to test the hypothesis that activation of adrenoceptors within the BNST facilitates the development of behavioral consequences of stress. To investigate this hypothesis, male Wistar rats were stressed (forced swimming, 15 min) and 24 h later received intra-BNST injections of vehicle, WB4101, RX821002, CGP20712, or ICI118,551, which are selective α(1), α(2), β(1), and β(2) adrenoceptor antagonists, respectively, 10 min before a 5-min forced swimming test. It was observed that administration of WB4101 (10 and 15 nmol), CGP20712 (5 and 10 nmol), or ICI118,551 (5 nmol) into the BNST reduced the immobility time of rats subjected to forced swimming test, indicating an antidepressant-like effect. These findings suggest that activation of α(1), β(1), and β(2) adrenoceptors in the BNST could be involved in the development of the behavioral consequences of stress. © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Antioxidant and Antifatigue Properties of the Aqueous Extract of Moringa oleifera in Rats Subjected to Forced Swimming Endurance Test

PubMed Central

Lamou, Bonoy; Taiwe, Germain Sotoing; Hamadou, André; Abene; Houlray, Justin; Atour, Mahamat Mey; Tan, Paul Vernyuy

2016-01-01

The effects of the aqueous extract of Moringa oleifera on swimming performance and related biochemical parameters were investigated in male Wistar rats (130–132 g). Four groups of rats (16 per group) were fed a standard laboratory diet and given distilled water, 100, 200, or 400 mg/kg of extract, respectively, for 28 days. On day 28, 8 rats from each group were subjected to the forced swimming test with tail load (10% of body weight). The remaining 8 rats per group were subjected to the 90-minute free swim. Maximum swimming time, glycemia, lactamia, uremia, triglyceridemia, hepatic and muscle glycogen, hematological parameters, and oxidative stress parameters (superoxide dismutase, catalase, reduced glutathione, and malondialdehyde) were measured. Results. M. oleifera extract increased maximum swimming time, blood hemoglobin, blood glucose, and hepatic and muscle glycogen reserves. The extract also increased the activity of antioxidant enzymes and decreased the blood concentrations of malondialdehyde. Furthermore, it decreased blood concentrations of lactate, triglycerides, and urea. In conclusion, the antifatigue properties of M. oleifera extract are demonstrated by its ability to improve body energy stores and tissue antioxidant capacity and to reduce the tissue build-up of lactic acid. PMID:26904162

Melatonin improve the sperm quality in forced swimming test induced oxidative stress in nandrolone treated Wistar rats.

PubMed

Minaii, Bagher; Moayeri, Ardeshir; Shokri, Saeed; Habibi Roudkenar, Mehryar; Golmohammadi, Taghi; Malek, Fatemeh; Barbarestani, Mohammad

2014-01-01

This study investigates the effects of melatonin on the sperm quality and testis weight after the combination of swimming exercise and nandrolone decanoate (DECA). Two groups of male Wistar rats were treated for eight weeks as follows; group A consist of CO (control), Sham, N (DECA), S (swimming) and NS (DECA plus swimming); and group B: Sham M (sham melatonin), M (melatonin), MN (melatonin plus DECA), MS (melatonin plus swimming), MNS (melatonin, DECA plus swimming). The motility of sperm was significantly improved in melatonin groups in comparison to N, S and NS groups (P≤0.05).  The left testes weight was decreased in N, NS and MNS groups, and the right testes weight was decreased in N,S,NS, MS and MNS groups in compare with the control group. This study concluded that melatonin probably could improve the sperm motility and sex organs weight after the combination of DECA and exercise.

Pharmacological enhancement of cannabinoid CB1 receptor activity elicits an antidepressant-like response in the rat forced swim test.

PubMed

Hill, Matthew N; Gorzalka, Boris B

2005-12-01

These experiments aimed to assess whether enhanced activity at the cannabinoid CB1 receptor elicits antidepressant-like effects. To examine this we administered 1 and 5 mg/kg doses of the endocannabinoid uptake inhibitor AM404; 5 and 25 microg/kg doses of HU-210, a potent CB1 receptor agonist; 1, 2.5 and 5 mg/kg of oleamide, which elicits cannabinoidergic actions; 1 and 5 mg/kg doses of AM 251, a selective CB1 receptor antagonist, as well as 10 mg/kg desipramine (a positive antidepressant control) and measured the duration of immobility, during a 5-min test session of the rat Porsolt forced swim test. Results demonstrated that administration of desipramine reduced immobility duration by about 50% and that all of AM404, oleamide and HU-210 administration induced comparable decreases in immobility that were blocked by pretreatment with AM 251. Administration of the antagonist AM 251 alone had no effect on immobility at either dose. These data suggest that enhancement of CB1 receptor signaling results in antidepressant effects in the forced swim test similar to that seen following conventional antidepressant administration.

Credit USAF, ca. 1943. Original housed in the Muroc Flight ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Credit USAF, ca. 1943. Original housed in the Muroc Flight Test Base, Unit History, 1 September 1942 - 30 June 1945. Alfred F. Simpson Historical Research Agency. United States Air Force. Maxwell AFB, Alabama. Historic view looking north across southwest end of swimming pool as army personnel work on finishing the pool bottom. View looks towards Mess Hall (T-10) on Second Street - Edwards Air Force Base, North Base, Swimming Pool, Second Street, Boron, Kern County, CA

Antidepressant-like effect of the organoselenium compound ebselen in mice: evidence for the involvement of the monoaminergic system.

PubMed

Posser, Thaís; Kaster, Manuella P; Baraúna, Sara Cristiane; Rocha, João B T; Rodrigues, Ana Lúcia S; Leal, Rodrigo B

2009-01-05

Ebselen [2-phenyl-1,2-benzisoselenazol-3(2H)-one] is a seleno-organic compound which possesses a potent antioxidant activity and has been shown to exert neuroprotective effects in vitro and in vivo in a variety of pro-oxidative insults. The present study investigates a possible antidepressant activity of ebselen using two predictive tests for antidepressant activity in rodents: the forced swimming test and tail suspension test. Additionally, the mechanisms involved in the antidepressant-like effect of ebselen in mice were also assessed. Ebselen (10 mg/kg, s.c.) decreased the immobility time in the forced swimming test without accompanying changes in ambulation in the open-field test. In contrast, the administration of ebselen (10-30 mg/kg) did not produce any effect in the tail suspension test. The anti-immobility effect of ebselen (10 mg/kg, s.c.) was not prevented by pre-treatment of mice with p-chlorophenylalanine (PCPA, 100 mg/kg, i.p., an inhibitor of serotonin synthesis, 4 consecutive days), NAN-190 (0.5 mg/kg, i.p., a serotonin 5-HT(1A) receptor antagonist) or ketanserin (5 mg/kg, i.p., a serotonin 5-HT(2A/2C) receptor antagonist). On the other hand, the pre-treatment of mice with prazosin (1 mg/kg, i.p., an alpha(1)-adrenoceptor antagonist), yohimbine (1 mg/kg, i.p., an alpha(2)-adrenoceptor antagonist), SCH23390 (0.05 mg/kg, s.c., a dopamine D(1) receptor antagonist) or sulpiride (50 mg/kg, i.p., a dopamine D(2) receptor antagonist) completely blocked the antidepressant-like effect of ebselen (10 mg/kg, s.c.) in the forced swimming test. It may be concluded that ebselen produces an antidepressant-like effect in the forced swimming test that seems to be dependent on its interaction with the noradrenergic and dopaminergic systems, but not with the serotonergic system.

Antidepressant-like responses in the forced swimming test elicited by glutathione and redox modulation.

PubMed

Rosa, Juliana M; Dafre, Alcir Luiz; Rodrigues, Ana Lúcia S

2013-09-15

Glutathione (GSH) displays a broad range of functions, among them a role as a neuromodulator with some neuroprotective properties. Taking into account that oxidative stress has been associated with depressive disorders, this study investigated the possibility that GSH, a major cell antioxidant, elicits an antidepressant-like effect in mice. Thus, GSH was administered by i.c.v. route to mice that were tested in the forced swimming test and in the tail suspension test, two predictive tests for antidepressant drug activity. In addition, GSH metabolism and the redox environment were modulated in order to study the possible mechanisms underlying the effects of GSH in the forced swimming test. The administration of GSH decreased the immobility time in the forced swimming test (300-3000nmol/site) and tail suspension test (100-1000nmol/site), consistent with an antidepressant-like effect. GSH depletion elicited by l-buthionine sulfoximine (3.2μmol/site, i.c.v.) did not alter the antidepressant-like effect of GSH, whereas the inhibition of extracellular GSH catabolism by acivicin (100nmol/site, i.c.v.) prevented the antidepressant-like effect of GSH. Moreover, a sub-effective dose (0.01nmol/site, i.c.v.) of the oxidizing agent DTNB (5,5'-dithiobis(2-nitrobenzoic acid)) potentiated the effect of GSH (100nmol/site, i.c.v.), while the pretreatment (25-100mg/kg, i.p.) with the reducing agent DTT (dl-dithiothreitol) prevented the antidepressant-like effect of GSH (300nmol/site, i.c.v.). DTNB (0.1nmol/site, i.c.v.), produced an antidepressant-like effect, per se, which was abolished by DTT (25mg/kg, i.p.). The results show, for the first time, that centrally administered GSH produces an antidepressant-like effect in mice, which can be modulated by the GSH metabolism and the thiol/disulfide reagents. The redox environment may constitute a new venue for future antidepressant-drug development. Copyright © 2013 Elsevier B.V. All rights reserved.

Influence of short-term inertial training on swimming performance in young swimmers.

PubMed

Naczk, Mariusz; Lopacinski, Artur; Brzenczek-Owczarzak, Wioletta; Arlet, Jarosław; Naczk, Alicja; Adach, Zdzisław

2017-05-01

The aim of this study was to evaluate the influence of dry-land inertial training (IT) on muscle force, muscle power, and swimming performance. Fourteen young, national-level, competitive swimmers were randomly divided into IT and control (C) groups. The experiment lasted four weeks, during which time both groups underwent their regular swimming training. In addition, the IT group underwent IT using the Inertial Training Measurement System (ITMS) three times per week. The muscle groups involved during the upsweep phase of the arm stroke in front crawl and butterfly stroke were trained. Before and after training, muscle force and power were measured under IT conditions. Simultaneously with the biomechanical measurements on the ITMS, the electrical activity of the triceps brachii was registered. After four weeks of training, a 12.8% increase in the muscle force and 14.2% increase in the muscle power (p < .05) were noted in the IT group. Moreover, electromyography amplitude of triceps brachii recorded during strength measurements increased by 22.7% in the IT group. Moreover, swimming velocity in the 100 m butterfly and 50 m freestyle improved significantly following the four weeks of dry-land IT (-1.86% and -0.76%, respectively). Changes in the C group were trivial. Moreover, values of force and power registered during the ITMS test correlated negatively with the 100 m butterfly and 50 m freestyle swimming times (r value ranged from -.80 to -.91). These results suggest that IT can be useful in swimming practice.

Comparison Between Elite and Subelite Swimmers on Dry Land and Tumble Turn Leg Extensor Force-Time Characteristics.

PubMed

Jones, Julian V; Pyne, David B; Haff, G Greg; Newton, Robert U

2018-06-01

Jones, JV, Pyne, DB, Haff, GG, and Newton, RU. Comparison between elite and subelite swimmers on dry land and tumble turn leg extensor force-time characteristics. J Strength Cond Res 32(6): 1762-1769, 2018-Elite swimmers demonstrate faster swimming turn times that are potentially a result of having better strength-power characteristics than subelite swimmers. We quantified differences between dry-land and swimming turn force-time characteristics in elite swimmers and subelite swimmers. Subelite (11 males: 17.4 ± 0.6 years; 10 females: 17.1 ± 0.6 years) and elite swimmers (15 male: 23.2 ± 2.3 years; 7 female: 21.6 ± 2.5 years) were tested in a cross-sectional design. All swimmers performed a body weight and loaded (20 kg females, 30 kg males) squat jump (SJ) on a portable force platform. On the same day, all swimmers completed swimming turn analyses using a force platform fixed within the pool wall. The magnitude of difference between groups was estimated using a standardized mean difference (effect size statistic). Elite male and female swimmers had superior swimming turn and dry-land force-time characteristics to subelite swimmers in all tests. The standardized mean differences between groups ranged from small to very large. The largest differences were SJ peak velocity unloaded (3.07 ± 1.0 m·s males, 3.49 ± 2.29 m·s females; standardized mean difference ± 90% confidence limits) and SJ peak power unloaded (2.59 ± 0.79 w male, 2.80 ± 1.64 w female) with elite male and female swimmers having a ∼25-50% higher performance than the subelites in both characteristics. Elite swimmers exhibit superior strength and power characteristics for the swimming turn compared with younger and less experienced swimmers. A well-planned and executed strength and conditioning program is needed for emerging swimmers to develop these qualities, as they transition to senior levels.

Antidepressant-like effect of a Ginkgo biloba extract (EGb761) in the mouse forced swimming test: role of oxidative stress.

PubMed

Rojas, Patricia; Serrano-García, Norma; Medina-Campos, Omar N; Pedraza-Chaverri, José; Ogren, Sven O; Rojas, Carolina

2011-10-01

EGb761 is a well-defined mixture of active compounds extracted from Ginkgo biloba leaves. This extract is used clinically due to its neuroprotective effects, exerted probably via its potent antioxidant or free radical scavenger action. Previous studies suggest that oxidative stress, via free radical production, may play an important role in depression and animal models for depression-like behavior. Preclinical studies have suggested that antioxidants may have antidepressants properties. The aim of this study was to investigate the antidepressant-like of EGb761 due to its antioxidant role against oxidative stress induced in the forced swimming test, the most widely used preclinical model for assessing antidepressant-like behavior. Male BALB/c mice were pretreated with EGb761 (10mg/kg, ip) daily for 17 days followed by the forced swimming test and spontaneous locomotor activity. Animals were sacrificed to evaluate lipid peroxidation, different antioxidant enzyme activities, serotonin and dopamine content in midbrain, hippocampus and prefrontal cortex. EGb761 significantly decreased the immobility time (39%) in the forced swimming test. This antidepressant-like effect of EGb761 was associated with a reduction in lipid peroxidation and superoxide radical production (indicated by a downregulation of Mn-superoxide dismutase activity), both of which are indicators of oxidative stress. The protective effect of EGb761 is not related to excitatory or inhibitory effects in locomotor activity, and was also associated with the modulation of serotonergic and dopaminergic neurotransmission. It is suggested that EGb761 produces an antidepressant-like effect, and that an antioxidant effect against oxidative stress may be partly responsible for its observed neuroprotective effects. Copyright © 2011 Elsevier B.V. All rights reserved.

[Reverse learning in WAG/Rij rats with depression-like behavior].

PubMed

Malyshev, A V; Zakharov, A M; Sarkisova, K Iu; Dubynin, V A

2012-01-01

Learning and reverse learning in a complex maze, behavior in the open field test, novelty-suppressed feeding test, and forced swimming test were studies in WAG/Rij and Wistar rats. As compared with Wistar rats, WAG/Rij rats more slowly learned the spatial task, more slowly performed in the learning and reverse learning tasks, and made more errors in the complex maze (18% of WAG/Rij rats didn't reach learning criterion). Moreover, WAG/Rij rats exhibited reduced grooming reactions in the open field test, longer latency of approaching to food in the novel open field, reduced amount of food consumed in the home cage in the novelty-suppressed feeding test, and increased immobility time in the forced swimming test. The results suggest cognitive impaiment in WAG/Rij rats with depression-like behavior.

Repeated forced-swimming test in intact female rats: behaviour, oestrous cycle and enriched environment.

PubMed

Domingues, Karolina; Spezia, Inaê; Theindl, Lais C; Suman, Patrick R; Lima, Fernanda B; Lino de Oliveira, Cilene

2018-03-27

Psychopharmacology used animal models to study the effects of drugs on brain and behaviour. The repeated forced-swimming test (rFST), which is used to assess the gradual effects of antidepressants on rat behaviour, was standardized only in males. Because of the known sex differences in rats, experimental conditions standardized for males may not apply to female rats. Therefore, the present work aimed to standardize experimental and housing conditions for the rFST in female rats. Young or adult Wistar female rats were housed in standard or enriched environments for different experimental periods. As assessed in tested and nontested females, all rats had reached sexual maturity by the time behavioural testing occurred. The rFST consisted of a 15-min session of forced swimming (pretest), followed by 5-min sessions at 1 (test), 7 (retest 1) and 14 days (retest 2) later. The oestrous cycle was registered immediately before every behavioural session. All sessions were videotaped for further analysis. The immobility time of female rats remained similar over the different sessions of rFST independent of the age, the phase of the oestrous cycle or the housing conditions. These data indicate that rFST in female Wistar rats may be reproducible in different experimental conditions.

Ethopharmacology of the antidepressant effect of clonazepam in diabetic rats.

PubMed

Gomez, R; Barros, H M

2000-06-01

Diabetes-associated depression may occur due to changes in the quality of life imposed by treatment, or may be a consequence of the biochemical changes accompanying the disease. It was our objective to evaluate the behaviors of diabetic rats through an animal model of depression, and determine if a positive GABA modulator agent, clonazepam, is an effective antidepressant. Wistar male rats were submitted to the forced-swimming test after 26 days of the induction of diabetes with streptozotocin (60 mg/kg). Test and retest days analyzed with an ethological approach. Clonazepam (control, 0.25, 0. 5, and 1.0 mg/kg) was administered IP 24, 5, and 1 h before the retest. Diabetic rats presented longer immobility duration during test and retest of forced swimming. Diabetic rats dived significantly less during the test. Clonazepam 0.25 and 0.5 mg/kg decreased immobility of diabetic rats with no consequences on the behaviors of nondiabetic rats. These results demonstrate that diabetic rats present more intense depressive-like behavior, such as immobility and lack of interest in exploring the environment, when exposed to the forced-swimming test. It is possible that decreased GABA function is involved in depression associated with diabetes, because a benzodiazepine partially counteracts these changes without modifying blood glucose and glycogen parameters.

Fertility of male adult rats submitted to forced swimming stress.

PubMed

Mingoti, G Z; Pereira, R N; Monteiro, C M R

2003-05-01

We investigated whether stress interferes with fertility during adulthood. Male Wistar rats (weighing 220 g in the beginning of the experiment) were forced to swim for 3 min in water at 32 degrees C daily for 15 days. Stress was assessed by the hot-plate test after the last stressing session. To assess fertility, control and stressed males (N = 15 per group) were mated with sexually mature normal females. Males were sacrificed after copulation. Stress caused by forced swimming was demonstrated by a significant increase in the latency of the pain response in the hot-plate test (14.6 +/- 1.25 s for control males vs 26.0 +/- 1.53 s for stressed males, P = 0.0004). No changes were observed in body weight, testicular weight, seminal vesicle weight, ventral prostate weight or gross histological features of the testes of stressed males. Similarly, no changes were observed in fertility rate, measured by counting live fetuses in the uterus of normal females mated with control and stressed males; no dead or incompletely developed fetuses were observed in the uterus of either group. In contrast, there was a statistically significant decrease in spermatid production demonstrated by histometric evaluation (154.96 +/- 5.41 vs 127.02 +/- 3.95 spermatids per tubular section for control and stressed rats, respectively, P = 0.001). These data demonstrate that 15 days of forced swimming stress applied to adult male rats did not impair fertility, but significantly decreased spermatid production. This suggests that the effect of stress on fertility should not be assessed before at least the time required for one cycle of spermatogenesis.

Beta-Alanine Supplementation Improves Throwing Velocities in Repeated Sprint Ability and 200-m Swimming Performance in Young Water Polo Players.

PubMed

Claus, Gabriel Machado; Redkva, Paulo Eduardo; Brisola, Gabriel Mota Pinheiro; Malta, Elvis Sousa; de Araujo Bonetti de Poli, Rodrigo; Miyagi, Willian Eiji; Zagatto, Alessandro Moura

2017-05-01

The purpose of this study was to investigate the effects of beta-alanine supplementation on specific tests for water polo. Fifteen young water polo players (16 ± 2 years) underwent a 200-m swimming performance, repeated-sprint ability test (RSA) with free throw (shooting), and 30-s maximal tethered eggbeater kicks. Participants were randomly allocated into two groups (placebo × beta-alanine) and supplemented with 6.4g∙day -1 of beta-alanine or a placebo for six weeks. The mean and total RSA times, the magnitude based inference analysis showed a likely beneficial effect for beta-alanine supplementation (both). The ball velocity measured in the throwing performance after each sprint in the RSA presented a very like beneficial inference in the beta-alanine group for mean (96.4%) and percentage decrement of ball velocity (92.5%, likely beneficial). Furthermore, the percentage change for mean ball velocity was different between groups (beta-alanine=+2.5% and placebo=-3.5%; p = .034). In the 30-s maximal tethered eggbeater kicks the placebo group presented decreased peak force, mean force, and fatigue index, while the beta-alanine group maintained performance in mean force (44.1%, possibly beneficial), only presenting decreases in peak force. The 200-m swimming performance showed a possibly beneficial effect (68.7%). Six weeks of beta-alanine supplementation was effective for improving ball velocity shooting in the RSA, maintaining performance in the 30-s test, and providing possibly beneficial effects in the 200-m swimming performance.

The antidepressant-like effects of topiramate alone or combined with 17β-estradiol in ovariectomized Wistar rats submitted to the forced swimming test.

PubMed

Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia; Olivera-López, Jorge I; Jaramillo, M Teresa

2014-09-01

There is a significant delay in the clinical response of antidepressant drugs, and antidepressant treatments produce side effects. We examined the relationship between 17β-estradiol and topiramate in ovariectomized Wistar rats submitted to the forced swimming test (FST). Topiramate was administered alone or combined with 17β-estradiol to ovariectomized rats submitted to the FST. Topiramate (20 mg/kg, P < 0.05; 30 mg/kg, P < 0.05) reduced immobility by increasing swimming; these effects were antagonized by finasteride (50 mg/kg). In interaction experiments, topiramate (10 mg/kg) plus 17β-estradiol (5 micrograms per rat; P < 0.05) reduced immobility by increasing swimming behavior. Besides, 17β-estradiol (2.5 micrograms per rat) shortened the onset of the antidepressant-like effects of topiramate (P < 0.05). In the open field test, topiramate alone or combined with 17β-estradiol (P < 0.05) reduced locomotion. Topiramate alone or combined with 17β-estradiol produced antidepressant-like actions; and 17β-estradiol shortened the onset of the antidepressant-like effects of topiramate.

Swimming performance in juvenile shortnose sturgeon (Acipenser brevirostrum): the influence of time interval and velocity increments on critical swimming tests

PubMed Central

Kieffer, James D.

2017-01-01

Abstract The most utilized method to measure swimming performance of fishes has been the critical swimming speed (UCrit) test. In this test, the fish is forced to swim against an incrementally increasing flow of water until fatigue. Before the water velocity is increased, the fish swims at the water velocity for a specific, pre-arranged time interval. The magnitude of the velocity increments and the time interval for each swimming period can vary across studies making the comparison between and within species difficult. This issue has been acknowledged in the literature, however, little empirical evidence exists that tests the importance of velocity and time increments on swimming performance in fish. A practical application for fish performance is through the design of fishways that enable fish to bypass anthropogenic structures (e.g. dams) that block migration routes, which is one of the causes of world-wide decline in sturgeon populations. While fishways will improve sturgeon conservation, they need to be specifically designed to accommodate the swimming capabilities specific for sturgeons, and it is possible that current swimming methodologies have under-estimated the swimming performance of sturgeons. The present study assessed the UCrit of shortnose sturgeon using modified UCrit to determine the importance of velocity increment (5 and 10 cm s−1) and time (5, 15 and 30 min) intervals on swimming performance. UCrit was found to be influenced by both time interval and water velocity. UCrit was generally lower in sturgeon when they were swum using 5cm s−1 compared with 10 cm s−1 increments. Velocity increment influences the UCrit more than time interval. Overall, researchers must consider the impacts of using particular swimming criteria when designing their experiments. PMID:28835841

A forced damped oscillation framework for undulatory swimming provides new insights into how propulsion arises in active and passive swimming.

PubMed

Bhalla, Amneet Pal Singh; Griffith, Boyce E; Patankar, Neelesh A

2013-01-01

A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions ("active" swimming) or by forces imparted by the surrounding fluid ("passive" swimming), is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD) simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained.

A Forced Damped Oscillation Framework for Undulatory Swimming Provides New Insights into How Propulsion Arises in Active and Passive Swimming

PubMed Central

Bhalla, Amneet Pal Singh; Griffith, Boyce E.; Patankar, Neelesh A.

2013-01-01

A fundamental issue in locomotion is to understand how muscle forcing produces apparently complex deformation kinematics leading to movement of animals like undulatory swimmers. The question of whether complicated muscle forcing is required to create the observed deformation kinematics is central to the understanding of how animals control movement. In this work, a forced damped oscillation framework is applied to a chain-link model for undulatory swimming to understand how forcing leads to deformation and movement. A unified understanding of swimming, caused by muscle contractions (“active” swimming) or by forces imparted by the surrounding fluid (“passive” swimming), is obtained. We show that the forcing triggers the first few deformation modes of the body, which in turn cause the translational motion. We show that relatively simple forcing patterns can trigger seemingly complex deformation kinematics that lead to movement. For given muscle activation, the forcing frequency relative to the natural frequency of the damped oscillator is important for the emergent deformation characteristics of the body. The proposed approach also leads to a qualitative understanding of optimal deformation kinematics for fast swimming. These results, based on a chain-link model of swimming, are confirmed by fully resolved computational fluid dynamics (CFD) simulations. Prior results from the literature on the optimal value of stiffness for maximum speed are explained. PMID:23785272

Estrogen alters behavior and forebrain c-fos expression in ovariectomized rats subjected to the forced swim test

PubMed Central

Rachman, Ilya M.; Unnerstall, James R.; Pfaff, Donald W.; Cohen, Rochelle S.

1998-01-01

Estrogen has been implicated in brain functions related to affective state, including hormone-related affective disorders in women. Although some reports suggest that estrogen appears to decrease vulnerability to affective disorders in certain cases, the mechanisms involved are unknown. We used the forced swim test (FST), a paradigm used to test the efficacy of antidepressants, and addressed the hypotheses that estrogen alters behavior of ovariectomized rats in the FST and the FST-induced expression of c-fos, a marker for neuronal activity, in the rat forebrain. The behaviors displayed included struggling, swimming, and immobility. One hour after the beginning of the test on day 2, the animals were perfused, and the brains were processed for c-fos immunocytochemistry. On day 1, the estradiol benzoate-treated animals spent significantly less time struggling and virtually no time in immobility and spent most of the time swimming. Control rats spent significantly more time struggling or being immobile during a comparable period. On day 2, similar behavioral patterns with still more pronounced differences were observed between estradiol benzoate and ovariectomized control groups in struggling, immobility, and swimming. Analysis of the mean number of c-fos immunoreactive cell nuclei showed a significant reduction in the estradiol benzoate versus control groups in areas of the forebrain relating to sensory, contextual, and integrative processing. Our results suggest that estrogen-induced neurochemical changes in forebrain neurons may translate into an altered behavioral output in the affective domain. PMID:9811905

The antidepressant effects of curcumin in the forced swimming test involve 5-HT1 and 5-HT2 receptors.

PubMed

Wang, Rui; Xu, Ying; Wu, Hong-Li; Li, Ying-Bo; Li, Yu-Hua; Guo, Jia-Bin; Li, Xue-Jun

2008-01-06

Curcuma longa is a main constituent of many traditional Chinese medicines, such as Xiaoyao-san, used to manage mental disorders effectively. Curcumin is a major active component of C. longa and its antidepressant-like effect has been previously demonstrated in the forced swimming test. The purpose of this study was to explore the possible contribution of serotonin (5-HT) receptors in the behavioral effects induced by curcumin in this animal model of depression. 5-HT was depleted by the tryptophan hydroxylase inhibitor p-chlorophenylalanine (PCPA, 100 mg/kg, i.p.) prior to the administration of curcumin, and the consequent results showed that PCPA blocked the anti-immobility effect of curcumin in forced swimming test, suggesting the involvement of the serotonergic system. Moreover, pre-treatment of pindolol (10 mg/kg, i.p., a beta-adrenoceptors blocker/5-HT(1A/1B) receptor antagonist), 4-(2'-methoxy-phenyl)-1-[2'-(n-2''-pyridinyl)-p-iodobenzamino-]ethyl-piperazine (p-MPPI, 1 mg/kg, s.c., a selective 5-HT(1A) receptor antagonist), or 1-(2-(1-pyrrolyl)-phenoxy)-3-isopropylamino-2-propanol (isamoltane, 2.5 mg/kg, i.p., a 5-HT(1B) receptor antagonist) was found to prevent the effect of curcumin (10 mg/kg) in forced swimming test. On the other hand, a sub-effective dose of curcumin (2.5 mg/kg, p.o.) produced a synergistic effect when given jointly with (+)-8-hydroxy-2-(di-n-propylamino)tetralin, (8-OH-DPAT, 1 mg/kg, i.p., a 5-HT(1A) receptor agonist), anpirtoline (0.25 mg/kg, i.p., a 5-HT(1B) receptor agonist) or ritanserin (4 mg/kg, i.p., a 5-HT(2A/2C) receptor antagonist), but not with ketanserin (5 mg/kg, i.p., a 5-HT(2A/2C) receptor antagonist with higher affinity to 5-HT(2A) receptor) or R(-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI, 1 mg/kg, i.p., a 5-HT(2A) receptor agonist). Taken together, these results indicate that the antidepressant-like effect of curcumin in the forced swimming test is related to serotonergic system and may be mediated by, at least in part, an interaction with 5-HT(1A/1B) and 5-HT(2C) receptors.

Anti-anxiety activity of successive extracts of Angelica archangelica Linn. on the elevated T-maze and forced swimming tests in rats.

PubMed

Kumar, Dinesh; Bhat, Zulfiqar Ali; Shah, M Y

2012-09-01

Angelica archangelica Linn. is widely used in food and liquor preparations and also in Kashmiri folk medicine to reduce anxiety. We evaluated the anxiolytic effect of successive extracts of A. archangelica linn. (SAE) on rats tested in the elevated T-maze test (an animal model of generalized anxiety) at doses that exhibit antidepressant-like activity in humans. A. archangelica (1 kg) was subjected to successive extraction in a soxhlet apparatus with solvents [petroleum ether (40-60 degrees C), chloroform, ethyl acetate, methanol and decoction with water] in order of increasing polarity (yield: 6.9%, 7.3%, 5.1%, 11.88% and 8.2% w/w, respectively). SAE were evaluated for anxiolytic effects using the elevated T-maze and forced swimming tests in rats. Oral dosing of diazepam (1 mg/kg) and extracts (50, 100 and 200 mg/kg) clearly showed an anxiolytic-like profile in the elevated T-maze test: it increased one-way escape and decreased inhibitory avoidance on the first, third and seventh day. In the forced swimming test, imipramine and SAE showed antidepressant- and anxiolytic-like effects as reflected by increased climbing time, swimming time and decreased immobility time on the first, third and seventh day. Aqueous and methanol extracts showed the most, petroleum ether (40-60 degrees C) and chloroform intermediate, and ethyl acetate the least anxiolytic activity (*P<0.05, **P<0.01, ***P< 0.001) in both models. These results suggest the anti-anxiety activity of various extracts of A. archangelica and strongly justify its use in traditional Indian medicine for the treatment of anxiety.

Further evidence for conditioned taste aversion induced by forced swimming.

PubMed

Masaki, Takahisa; Nakajima, Sadahiko

2005-01-31

A series of experiments with rats reported that aversion to a taste solution can be established by forced swimming in a water pool. Experiment 1 demonstrated that correlation of taste and swimming is a critical factor for this phenomenon, indicating associative (i.e., Pavlovian) nature of this learning. Experiment 2 showed that this learning obeys the Pavlovian law of strength, by displaying a positive relationship between the duration of water immersion in training and the taste aversion observed in subsequent testing. Experiment 3 revealed that swimming rather than being wet is the critical agent, because a water shower did not endow rats with taste aversion. Experiment 4 found that taste aversion was a positive function of water level of the pools in training (0, 12 or 32 cm). These results, taken together, suggest that energy expenditure caused by physical exercise might be involved in the development of taste aversion.

Repeated rat-forced swim test: reducing the number of animals to evaluate gradual effects of antidepressants.

PubMed

Mezadri, T J; Batista, G M; Portes, A C; Marino-Neto, J; Lino-de-Oliveira, C

2011-02-15

The forced swim test (FST) is a pre-clinical test to short and long term treatment with antidepressant drugs (ADT), which requires between-subject designs. Herein a modified protocol of the FST using within-subject design (repeated rat-FST) was evaluated. Male Wistar rats were submitted to 15 min of swimming (Day 1: pretest) followed by three subsequent 5 min-swimming tests one week apart (Day 2: test, Day 7: retest 1, Day 14: retest 2). To determine the temporal and factorial characteristics of the variables scored in the repeated rat-FST, the protocol was carried out in untreated animals (E1). To validate the method, daily injections of Fluoxetine (FLX, 2.5mg/kg, i.p.) or saline were given over a 2-week period (E2). Tests and retests have been videotaped for further register of the latency, frequency and duration of behaviors. Over retesting the latency to immobility decreased whereas duration of immobility tended to increase. Factorial analysis revealed that the test, the retest 1 as well as the retest 2 have variables suitable to detection of antidepressant-like effects of ADT. Compared to saline, FLX chronically administrated reduced duration of immobility whereas increased duration of swimming in retest 2. The data suggest that repeated rat-FST detected the gradual increase in the efficacy of low doses of FLX over time. Therefore, repeated rat-FST seemed suitable to detect short and long term effects of selective serotonin reuptake inhibitors, or other ADT, thus reducing the number of animals used in the screenings of this type of compounds. © 2010 Elsevier B.V. All rights reserved.

Effects of Laminaria japonica polysaccharides on exercise endurance and oxidative stress in forced swimming mouse model.

PubMed

Yan, Feiwei; Hao, Haitao

2016-12-01

Polysaccharides are the major active ingredients responsible for the bioactivities of Laminaria japonica. However, the effects of L. japonica polysaccharides (LJP) on exercise endurance and oxidative stress have never been investigated. Therefore, this study was conducted to investigate the effects of LJP on exercise endurance and oxidative stress in a forced swimming mouse model. The animals were divided into four groups, namely the control (C), LJP-75, LJP-150, and LJP-300 groups, which received physiological saline and 75, 150, and 300 mg kg(-1) LJP, respectively, by gavage once a day for 28 days. This was followed by a forced swimming test and measurements of various biochemical parameters. LJP increased swimming time to exhaustion, the liver and muscle glycogen content, and levels of superoxide dismutase, glutathione peroxidase, and catalase in the serum, liver, and muscle, which were accompanied by corresponding decreases in the malondialdehyde (MDA) content of the same tissues. Furthermore, decreases in blood lactic acid and serum myeloperoxidase (MPO) levels were observed. LJP enhanced exercise endurance and protected mice against exhaustive exercise-induced oxidative stress.

Effects of Methyl Jasmonate on Acute Stress Responses in Mice Subjected to Forced Swim and Anoxic Tests

PubMed Central

Aluko, Oritoke M.; Umukoro, Solomon; Annafi, Olajide S.; Adewole, Folashade A.; Omorogbe, Osarume

2015-01-01

Methyl jasmonate (MJ) is an anti-stress hormone released by plants in response to external stressors and aids adaptation to stress. In this study, we evaluated the anti-stress activity of MJ using the forced swim endurance test (FSET) and anoxic tolerance test in mice. Male Swiss mice were given MJ (25–100 mg/kg, i.p) 30 min before the FSET and anoxic test were carried out. The first occurrence of immobility, duration of immobility, time spent in active swimming, and latency to exhaustion were assessed in the FSET. The onset to anoxic convulsion was measured in the anoxic tolerance test. MJ significantly (p < 0.05) delayed the first occurrence of immobility and shortened the period of immobility, which indicates anti-stress property. MJ also increased the time spent in active swimming and prolonged the latency to exhaustion, which further suggests anti-stress activity. In addition, it also exhibited anti-stress property as evidenced by prolonged latency to first appearance of anoxic convulsions. The results of this study suggest that MJ demonstrated anti-stress activity and may be useful as an energizer in times of body weakness or exhaustion. Although more studies are necessary before concluding on how MJ exerts its anti-stress activity, the present data suggest an action similar to adaptogens in boosting energy and resilience in the face of stress. PMID:26839844

Hippocampal 3alpha,5alpha-THP may alter depressive behavior of pregnant and lactating rats.

PubMed

Frye, Cheryl A; Walf, Alicia A

2004-07-01

The 5alpha-reduced metabolite of progesterone (P), 5alpha-pregnan-3alpha-ol-20-one (3alpha,5alpha-THP), may mediate progestins' effects to reduce depressive behavior of female rats in part through actions in the hippocampus. To investigate, forced swim test behavior and plasma and hippocampal progestin levels were assessed in groups of rats expected to differ in their 3alpha,5alpha-THP levels due to endogenous differences (pregnant and postpartum), administration of a 5alpha-reductase inhibitor (finasteride; 50 mg/kg sc), and/or gestational stress [prenatal stress (PNS)], an animal model of depression. Pregnant rats had higher plasma and hippocampal 3alpha,5alpha-THP levels and less depressive behavior (decreased immobility, increased struggling and swimming) in the forced swim test than did postpartum rats. Finasteride, compared to vehicle-administration, reduced plasma and hippocampal 3alpha,5alpha-THP levels and increased depressive behavior (increased immobility, decreased struggling and swimming). PNS was associated with lower hippocampal, but not plasma, 3alpha,5alpha-THP levels and increased swimming compared to that observed in control rats. Together, these data suggest that 3alpha,5alpha-THP in the hippocampus may mediate antidepressive behavior of female rats.

[Electromagnetic Shielding Alters Behaviour of Rats].

PubMed

Temuryants, N A; Kostyuk, A S; Tumanyants, K N

2015-01-01

It has been found that long-term electromagnetic shielding (19 hours per day for 10 days) leads to an increase in the duration of passive swimming time in male rats, decrease the duration of active swimming in the "forced swim" test as well as decrease of libido. On the other hand animals kept under the "open field" conditions do not show significant deviations from their normal behavior. Therefore, one could conclude that moderate electromagnetic shielding causes a depression-like state in rats.

Forced swimming and imipramine modify plasma and brain amino acid concentrations in mice.

PubMed

Murakami, Tatsuro; Yamane, Haruka; Tomonaga, Shozo; Furuse, Mitsuhiro

2009-01-05

The relationships between monoamine metabolism and forced swimming or antidepressants have been well studied, however information is lacking regarding amino acid metabolism under these conditions. Therefore, the aim of the present study was to investigate the effects of forced swimming and imipramine on amino acid concentrations in plasma, the cerebral cortex and the hypothalamus in mice. Forced swimming caused cerebral cortex concentrations of L-glutamine, L-alanine, and taurine to be increased, while imipramine treatment caused decreased concentrations of L-glutamate, L-alanine, L-tyrosine, L-methionine, and L-ornithine. In the hypothalamus, forced swimming decreased the concentration of L-serine while imipramine treatment caused increased concentration of beta-alanine. Forced swimming caused increased plasma concentration of taurine, while concentrations of L-serine, L-asparagine, L-glutamine and beta-alanine were decreased. Imipramine treatment caused increased plasma concentration of all amino acid, except for L-aspartate and taurine. In conclusion, forced swimming and imipramine treatment modify central and peripheral amino acid metabolism. These results may aid in the identification of amino acids that have antidepressant-like effects, or may help to refine the dosages of antidepressant drugs.

BDNF-GSK-3β-β-Catenin Pathway in the mPFC Is Involved in Antidepressant-Like Effects of Morinda officinalis Oligosaccharides in Rats.

PubMed

Xu, Ling-Zhi; Xu, De-Feng; Han, Ying; Liu, Li-Jing; Sun, Cheng-Yu; Deng, Jia-Hui; Zhang, Ruo-Xi; Yuan, Ming; Zhang, Su-Zhen; Li, Zhi-Meng; Xu, Yi; Li, Jin-Sheng; Xie, Su-Hua; Li, Su-Xia; Zhang, Hong-Yan; Lu, Lin

2017-01-01

Morinda officinalis oligosaccharides have been reported to exert neuroprotective and antidepressant-like effects in the forced swim test in mice. However, the mechanisms that underlie the antidepressant-like effects of Morinda officinalis oligosaccharides are unclear. Chronic unpredictable stress and forced swim test were used to explore the antidepressant-like effects of Morinda officinalis oligosaccharides and resilience to stress in rats. The phosphoinositide-3 kinase inhibitor LY294002 was microinjected in the medial prefrontal cortex to explore the role of glycogen synthase kinase-3β in the antidepressant-like effects of Morinda officinalis oligosaccharides. The expression of brain-derived neurotrophic factor, phosphorylated-Ser9-glycogen synthase kinase 3β, β-catenin, and synaptic proteins was determined in the medial prefrontal cortex and the orbitofrontal cortex by western blot. We found that Morinda officinalis oligosaccharides effectively ameliorated chronic unpredictable stress-induced depression-like behaviors in the sucrose preference test and forced swim test. The Morinda officinalis oligosaccharides also significantly rescued chronic unpredictable stress-induced abnormalities in the brain-derived neurotrophic factor-glycogen synthase kinase-3β-β-catenin pathway and synaptic protein deficits in the medial prefrontal cortex but not orbitofrontal cortex. The activation of glycogen synthase kinase-3β by the phosphoinositide-3 kinase inhibitor LY294002 abolished the antidepressant-like effects of Morinda officinalis oligosaccharides in the forced swim test. Naïve rats that were treated with Morinda officinalis oligosaccharides exhibited resilience to chronic unpredictable stress, accompanied by increases in the expression of brain-derived neurotrophic factor, phosphorylated-Ser9-glycogen synthase kinase-3β, and β-catenin in the medial prefrontal cortex. Our findings indicate that the brain-derived neurotrophic factor-glycogen synthase kinase-3β-β-catenin pathway in the medial prefrontal cortex may underlie the antidepressant-like effect of Morinda officinalis oligosaccharides and resilience to stress. © The Author 2016. Published by Oxford University Press on behalf of CINP.

Stimulation of the metabotropic glutamate (mGlu) 2 receptor attenuates the MK-801-induced increase in the immobility time in the forced swimming test in rats.

PubMed

Kawaura, Kazuaki; Karasawa, Jun-Ichi; Hikichi, Hirohiko

2016-02-01

Negative symptoms of schizophrenia are poorly managed using the currently available antipsychotics. Previous studies indicate that agonists of the metabotropic glutamate (mGlu) 2/3 receptors may provide a novel approach for the treatment of schizophrenia. However, the effects of mGlu2/3 receptor agonists or mGlu2 receptor positive allosteric modulators have not yet been clearly elucidated in animal models of the negative symptoms of schizophrenia. Recently, we reported that the forced swimming test in rats treated with subchronic MK-801, an NMDA receptor antagonist, may be regarded as a useful test to evaluate the activities of drugs against the negative symptoms of schizophrenia. We evaluated the effects of LY379268, an mGlu2/3 receptor agonist, and BINA, an mGlu2 receptor positive allosteric modulator, on the hyperlocomotion induced by acute administration of MK-801 (0.15mg/kg, sc) and on the increase in the immobility time in the forced swimming test induced by subchronic treatment with MK-801 (0.5mg/kg, sc, twice a day for 7 days) in rats. Both LY379268 (3mg/kg, sc) and BINA (100mg/kg, ip) attenuated the increase in the immobility time induced by subchronic treatment with MK-801 at the same doses at which they attenuated the MK-801-induced increase in locomotor activity, but had no effect on the immobility time in saline-treated rats. The present results suggest that stimulation of the mGlu2 receptor attenuates the increase in the immobility time in the forced swimming test elicited by subchronic administration of MK-801, and may be potentially useful for treatment of the negative symptoms of schizophrenia. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Credit USAF, ca. 1943. Original housed in the Muroc Flight ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Credit USAF, ca. 1943. Original housed in the Muroc Flight Test Base, Unit History, 1 September 1942 - 30 June 1945. Alfred F. Simpson Historical Research Agency. United States Air Force. Maxwell AFB, Alabama. Historic view looking northeast along southeast edge of swimming pool during construction. The wavy edge of the pool visible here remains as a ground surface feature in 1995. Building in the background is the second Bachelor Officers' Quarters (T-15) built in 1943 - Edwards Air Force Base, North Base, Swimming Pool, Second Street, Boron, Kern County, CA

Swimming activity in marine fish.

PubMed

Wardle, C S

1985-01-01

Marine fish are capable of swimming long distances in annual migrations; they are also capable of high-speed dashes of short duration, and they can occupy small home territories for long periods with little activity. There is a large effect of fish size on the distance fish migrate at slow swimming speeds. When chased by a fishing trawl the effect of fish size on swimming performance can decide their fate. The identity and thickness of muscle used at each speed and evidence for the timing of myotomes used during the body movement cycle can be detected using electromyogram (EMG) electrodes. The cross-sectional area of muscle needed to maintain different swimming speeds can be predicted by relating the swimming drag force to the muscle force. At maximum swimming speed one completed cycle of swimming force is derived in sequence from the whole cross-sectional area of the muscles along the two sides of the fish. This and other aspects of the swimming cycle suggest that each myotome might be responsible for generating forces involved in particular stages of the tail sweep. The thick myotomes at the head end shorten during the peak thrust of the tail blade whereas the thinner myotomes nearer the tail generate stiffness appropriate for transmission of these forces and reposition the tail for the next cycle.

Sex differences associated with intermittent swim stress.

PubMed

Warner, Timothy A; Libman, Matthew K; Wooten, Katherine L; Drugan, Robert C

2013-11-01

Various animal models of depression have been used to seek a greater understanding of stress-related disorders. However, there is still a great need for novel research in this area, as many individuals suffering from depression are resistant to current treatment methods. Women have a higher rate of depression, highlighting the need to investigate mechanisms of sex differences. Therefore, we employed a new animal model to assess symptoms of depression, known as intermittent swim stress (ISS). In this model, the animal experiences 100 trials of cold water swim stress. ISS has already been shown to cause signs of behavioral depression in males, but has yet to be assessed in females. Following ISS exposure, we looked at sex differences in the Morris water maze and forced swim test. The results indicated a spatial learning effect only in the hidden platform task between male and female controls, and stressed and control males. A consistent spatial memory effect was only seen for males exposed to ISS. In the forced swim test, both sexes exposed to ISS exhibited greater immobility, and the same males and females also showed attenuated climbing and swimming, respectively. The sex differences could be due to different neural substrates for males and females. The goal of this study was to provide the first behavioral examination of sex differences following ISS exposure, so the stage of estrous cycle was not assessed for the females. This is a necessary future direction for subsequent experiments. The current article highlights the importance of sex differences in response to stress.

Forced swimming sabotages the morphological and synaptic maturation of newborn granule neurons and triggers a unique pro-inflammatory milieu in the hippocampus.

PubMed

Llorens-Martín, María; Jurado-Arjona, Jerónimo; Bolós, Marta; Pallas-Bazarra, Noemí; Ávila, Jesús

2016-03-01

Recent experimental data suggest that mood disorders are related to inflammatory phenomena and have led to the "inflammatory hypothesis of depression". Given that the hippocampus is one of the most affected areas in these disorders, we used a model of acute stress (the Porsolt test) to evaluate the consequences of forced swimming on two crucial events related to the pathophysiology of major depression: the functional maturation of newborn granule neurons; and the hippocampal inflammatory milieu. Using PSD95:GFP-expressing retroviruses, we found that forced swimming selectively alters the dendritic morphology of newborn neurons and impairs their connectivity by reducing the number and volume of their postsynaptic densities. In addition, acute stress triggered a series of morphological changes in microglial cells, together with an increase in microglial CD68 expression, thus suggesting the functional and morphological activation of this cell population. Furthermore, we observed an intriguing change in the hippocampal inflammatory milieu in response to forced swimming. Importantly, the levels of several molecules affected by acute stress (such as Interleukin-6 and eotaxin) have been described to also be altered in patients with depression and other mood disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

Tethered Swimming for the Evaluation and Prescription of Resistance Training in Young Swimmers.

PubMed

Papoti, Marcelo; da Silva, Adelino S R; Kalva-Filho, Carlos Augusto; Araujo, Gustavo Gomes; Santiago, Vanessa; Martins, LuizEduardo Barreto; Cunha, Sérgio Augusto; Gobatto, Claudio Alexandre

2017-02-01

The aims of the present study were 1) to evaluate the effects of 11 weeks of a typical free-swimming training program on aerobic and stroke parameters determined in tethered swimming (Study 1; n=13) and 2) to investigate the responses of tethered swimming efforts, in addition to free-swimming sessions, through 7 weeks of training (Study 2; n=21). In both studies, subjects performed a graded exercise test in tethered swimming (GET) to determine anaerobic threshold (AnT), stroke rate at AnT (SR AnT ), peak force at GET (PF GET ) and peak blood lactate ([La-] GET ). Participants also swam 100-, 200- and 400-m lengths to evaluate performance. In Study 2, swimmers were divided into control (i. e., only free-swimming; GC [n=11]) and tethered swimming group (i. e., 50% of the main session; G TS [n=10]). The results of Study 1 demonstrate that AnT, PF GET , [La - ] GET and 200-m performance were improved with free-swimming training. The SR AnT decreased with training. In Study 2, free-swimming performance and most of the graded exercise test parameters were not altered in either group. However, [La-] GET improved only for G TS . These results demonstrate that aerobic parameters obtained in tethered swimming can be used to evaluate free-swimming training responses, and the addition of tethered efforts during training routine improves the lactate production capacity of swimmers. © Georg Thieme Verlag KG Stuttgart · New York.

Toxic cocaine- and convulsant-induced modification of forced swimming behaviors and their interaction with ethanol: comparison with immobilization stress

PubMed Central

Hayase, Tamaki; Yamamoto, Yoshiko; Yamamoto, Keiichi

2002-01-01

Background Swimming behaviors in the forced swimming test have been reported to be depressed by stressors. Since toxic convulsion-inducing drugs related to dopamine [cocaine (COC)], benzodiazepine [methyl 6,7-dimethoxy-4-ethyl-β-carboline-carboxylate (DMCM)], γ-aminobutyric acid (GABA) [bicuculline (BIC)], and glutamate [N-methyl-D-aspartate (NMDA)] receptors can function as stressors, the present study compared their effects on the forced swimming behaviors with the effects of immobilization stress (IM) in rats. Their interactions with ethanol (EtOH), the most frequently coabused drug with COC which also induces convulsions as withdrawal symptoms but interferes with the convulsions caused by other drugs, were also investigated. Results Similar to the IM (10 min) group, depressed swimming behaviors (attenuated time until immobility and activity counts) were observed in the BIC (5 mg/kg IP) and DMCM (10 mg/kg IP) groups at the 5 h time point, after which no toxic behavioral symptoms were observed. However, they were normalized to the control levels at the 12 h point, with or without EtOH (1.5 g/kg IP). In the COC (60 mg/kg IP) and NMDA (200 mg/kg IP) groups, the depression occurred late (12 h point), and was normalized by the EtOH cotreatment. At the 5 h point, the COC treatment enhanced the swimming behaviors above the control level. Conclusions Although the physiological stress (IM), BIC, and DMCM also depressed the swimming behaviors, a delayed occurrence and EtOH-induced recovery of depressed swimming were observed only in the COC and NMDA groups. This might be correlated with the previously-reported delayed responses of DA and NMDA neurons rather than direct effects of the drugs, which could be suppressed by EtOH. Furthermore, the characteristic psychostimulant effects of COC seemed to be correlated with an early enhancement of swimming behaviors. PMID:12425723

Anhedonia but not passive floating is an indicator of depressive-like behavior in two chronic stress paradigms.

PubMed

Stepanichev, Mikhail Yu; Tishkina, Anna O; Novikova, Margarita R; Levshina, Irina P; Freiman, Sofiya V; Onufriev, Mikhail V; Levchenko, Olga A; Lazareva, Natalia A; Gulyaeva, Natalia V

2016-01-01

Depression is the most common form of mental disability in the world. Depressive episodes may be precipitated by severe acute stressful events or by mild chronic stressors. Studies on the mechanisms of depression require both appropriate experimental models (most of them based on the exposure of animals to chronic stressors), and appropriate tests for assessment of depressive states. In this study male Wistar rats were exposed to two different chronic stress paradigms: an eight-week chronic unpredictable mild stress or a two-week combined chronic stress. The behavioral effects of stress were evaluated using sucrose preference, forced swim and open field tests. After the exposure to chronic unpredictable mild stress, anhedonia was developed, activity in the open field increased, while no changes in the duration of passive floating could be detected. After chronic combined stress, anhedonia was also evident, whereas behavior in the open field and forced swim test did not change. The levels of corticosterone in the blood and brain structures involved in stress-response did not differ from control in both experiments. The absence of significant changes in corticosterone levels and passive floating may be indicative of the adaptation of animals to chronic stress. Anhedonia appears to be a more sensitive indicator of depressive-like behavioral effects of chronic stress as compared to behavior in the forced swim or open field tests.

Antidepressant-like effect of folic acid: Involvement of NMDA receptors and L-arginine-nitric oxide-cyclic guanosine monophosphate pathway.

PubMed

Brocardo, Patrícia de Souza; Budni, Josiane; Lobato, Kelly Ribas; Kaster, Manuella Pinto; Rodrigues, Ana Lúcia S

2008-11-19

Antidepressant-like activity of folic acid in forced swimming test and in the tail suspension test was demonstrated previously by our group. In this study we investigated the involvement of N-methyl-d-aspartate (NMDA) receptors and l-arginine-nitric oxide (NO)-cyclic guanosine monophosphate pathway in its antidepressant-like effect in the forced swimming test in mice. The antidepressant-like effect of folic acid (10 nmol/site, i.c.v.) was prevented by the pretreatment of mice with NMDA (0.1 pmol/site, i.c.v.), l-arginine (750 mg/kg, i.p., substrate for nitric oxide synthase), S-nitroso-N-acetyl-penicillamine (SNAP, 25 microg/site, i.c.v, a NO donor) or sildenafil (5 mg/kg, i.p., phosphodiesterase 5 inhibitor). The administration of 7-nitroindazole (25 and 50 mg/kg, i.p., a specific neuronal nitric oxide synthase (nNOS) inhibitor) or methylene blue (20 mg/kg, i.p., direct inhibitor of both nitric oxide synthase and soluble guanylate cyclase) in combination with a sub-effective dose of folic acid (1 nmol/site, i.c.v.) reduced the immobility time in the FST as compared with either drug alone. Together the results suggest that the antidepressant-like effect of folic acid in the forced swimming test is dependent on an inhibition of either NMDA receptors or NO and cGMP synthesis.

Chelidonic acid evokes antidepressant-like effect through the up-regulation of BDNF in forced swimming test.

PubMed

Jeong, Hyun-Ja; Yang, Shi-Young; Kim, Hee-Yun; Kim, Na-Rae; Jang, Jae-Bum; Kim, Hyung-Min

2016-08-01

Depression is usually accompanied by neuro-inflammatory reactions. Chelidonic acid, in particular, has shown anti-inflammatory effects. The objective of this study was to evaluate the anti-depressant effects of chelidonic acid and to discuss the potential mechanisms of a forced swimming test. Chelidonic acid was administered orally once a day for 14 days. On the 14th day, chelidonic acid resulted in a significant decrease in immobility time during the forced swimming test without alteration of locomotor activity, in an open field test. Chelidonic acid also increased the number of nissl bodies in the hippocampus. Brain-derived neurotrophic factor expression and extracellular signal-regulated protein kinase phosphorylation in the hippocampus were up-regulated by the administration of chelidonic acid. Chelidonic acid administration significantly increased the mRNA expression of hippocampal estrogen receptor-β. The levels of hippocampal interleukin (IL)-1β, IL-6, and tumor necrosis factor-α were effectively attenuated by the administration of chelidonic acid. In addition, chelidonic acid significantly increased the levels of 5-hydroxytryptamine (serotonin), dopamine, and norepinephrine compared with those levels for the mice that were administered distilled water in the hippocampus. These results suggest that chelidonic acid might serve as a new therapeutic strategy for the regulation of depression associated with inflammation. © 2016 by the Society for Experimental Biology and Medicine.

Glucometabolic effects of single and repeated exposure to forced-swimming stressor in Sprague-Dawley rats.

PubMed

Morakinyo, Ayodele Olufemi; Iranloye, Bolanle Olubusola; Ogunsola, Oluseyi Abimbola

2018-04-01

We aimed to evaluate the effects of a single (acute) and repeated (chronic) exposure to forced-swimming stressor on glucose tolerance, insulin sensitivity, lipid profile and glycogen content in male rats. Thirty adult male Sprague-Dawley rats (12 weeks old) were divided randomly into five groups: control group, single exposure (SE) to forced-swim stressor, repeated exposure to forced-swim stressor for 7 days (RE7), 14 days (RE14) and 28 days (RE28). Glucose tolerance test and Homeostatic Model Assessment-Insulin Resistance (HOMA-IR) were undertaken on fasting rats to obtain glucose and insulin profiles. ELISA was performed to assess plasma insulin and corticosterone levels. Total cholesterol, triglyceride, high- and low-density lipoproteins, hepatic and skeletal glycogen content were also determined. Repeated exposure to stressor induced glucose intolerance and insulin resistance in the experimental rats. Results showed that all RE groups exhibited a significantly higher area under the curve compared with others (p=0.0001); similarly, HOMA-IR increased (p=0.0001) in all RE groups compared with control. Prolonged exposure to stressor significantly increased the plasma insulin and corticosterone levels but decreased the glycogen content in the liver and skeletal muscle when compared with the control group. Additionally, chronic stressor significantly increased the total cholesterol and triglyceride levels, however, acute stressor produced significantly elevated high-density lipoproteins level. In conclusion, repeated exposure to forced-swimming stressor induced glucose intolerance and insulin resistance in rats by disrupting the insulin sensitivity as well as heightening the glycogenolysis in the liver and skeletal muscle. Acute stressor was unable to cause glucose intolerance and insulin resistance but it appears that may have a positive effect on the lipid metabolism.

Effect of dielectrophoretic force on swimming bacteria.

PubMed

Tran, Ngoc Phu; Marcos

2015-07-01

Dielectrophoresis (DEP) has been applied widely in bacterial manipulation such as separating, concentrating, and focusing. Previous studies primarily focused on the collective effects of DEP force on the bacterial population. However, the influence of DEP force on the swimming of a single bacterium had not been investigated. In this study, we present a model to analyze the effect of DEP force on a swimming helically flagellated bacterium, particularly on its swimming direction and velocity. We consider a simple DEP force that acts along the X-direction, and its strength as well as direction varies with the X- and Y-positions. Resistive force theory is employed to compute the hydrodynamic force on the bacterium's flagellar bundle, and the effects of both DEP force and rotational diffusion on the swimming of the bacterium are simultaneously taken into consideration using the Fokker-Planck equation. We show the mechanism of how DEP force alters the orientation and velocity of the bacterium. In most cases, the DEP force dominantly influences the orientation of the swimming bacterium; however, when the DEP force strongly varies along the Y-direction, the rotational diffusion is also responsible for determining the bacterium's reorientation. More interestingly, the variance of DEP force along the Y-direction causes the bacterium to experience a translational velocity perpendicular to its primary axis, and this phenomenon could be utilized to focus the bacteria. Finally, we show the feasibility of applying our findings to achieve bacterial focusing. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Eleutherococcus senticosus Cortex on Recovery from the Forced Swimming Test and Fatty Acid β-Oxidation in the Liver and Skeletal Muscle of mice.

PubMed

Sumiyoshi, Maho; Kimura, Yoshiyuki

2016-03-01

The root and stem barks of Eleutherococcus senticosus have been used to treat emotional and physical fatigue in China, Russia, Korea, and Japan. The effects of E. senticosus on recovery from physical fatigue and the expenditure of energy currently remain unclear. We herein examined the effects of E. senticosus extract on recovery from physical fatigue after the forced swimming test as well as fatty acid β-oxidation in the liver and skeletal muscle of mice. 1) Physical fatigue; E. senticosus extract (500 and 1000 mg/kg, twice daily) was administered orally to ICR male mice for 7 consecutive days. After swimming had been performed for 15 min, each mouse was placed on the cover of a 100-mm culture plate, and the time for each mouse to move away from the cover was measured. 2) Fatty acid β-oxidation in the liver and skeletal muscle; E. senticosus extract (500 and 1000 mg/kg) was administered orally twice daily to C57BL/6J male mice for 21 consecutive days. The initial and final body and liver weight were measured, and then fatty acid β-oxidation activity in the liver and skeletal muscle was measured by methods using [1- 14 C] palmitic acid. Recovery times after forced swimming were shorter in E. senticosus extract (500 and 1000 mg/kg)-treated mice than in vehicle-treated mice. The body and liver weight had no effect by the oral administration of E. senticosus extract, vitamin mixture and L-carnitine. Fatty acid β-oxidation activity in skeletal muscle was increased by E. senticosus extract (500 and 1000 mg/kg). E. senticosus may enhance recovery from physical fatigue induced by forced swimming by accelerating energy changes through fatty acid β-oxidation in skeletal muscle.

The Effects of Inhaled Pimpinella peregrina Essential Oil on Scopolamine-Induced Memory Impairment, Anxiety, and Depression in Laboratory Rats.

PubMed

Aydin, Emel; Hritcu, Lucian; Dogan, Gulden; Hayta, Sukru; Bagci, Eyup

2016-11-01

In the present study, we identified the effects of inhaled Pimpinella peregrina essential oil (1 and 3 %, for 21 continuous days) on scopolamine-induced memory impairment, anxiety, and depression in laboratory rats. Y-maze and radial arm-maze tests were used for assessing memory processes. Also, the anxiety and depressive responses were studied by means of the elevated plus-maze and forced swimming tests. The scopolamine alone-treated rats exhibited the following: decrease of the spontaneous alternation percentage in Y-maze test, increase of the number of working and reference memory errors in radial arm-maze test, along with decrease of the exploratory activity, the percentage of the time spent and the number of entries in the open arm within elevated plus-maze test and decrease of swimming time and increase of immobility time within forced swimming test. Inhalation of the P. peregrina essential oil significantly improved memory formation and exhibited anxiolytic- and antidepressant-like effects in scopolamine-treated rats. Our results suggest that the P. peregrina essential oil inhalation ameliorates scopolamine-induced memory impairment, anxiety, and depression. Moreover, studies on the P. peregrina essential oil may open a new therapeutic window for the prevention of neurological abnormalities closely related to Alzheimer's disease.

Adaptation of the pituitary-adrenal axis to daily repeated forced swim exposure in rats is dependent on the temperature of water.

PubMed

Rabasa, Cristina; Delgado-Morales, Raúl; Gómez-Román, Almudena; Nadal, Roser; Armario, Antonio

2013-11-01

Comparison of exposure to certain predominantly emotional stressors reveals a qualitatively similar neuroendocrine response profile as well as a reduction of physiological responses after daily repeated exposure (adaptation). However, particular physical components of the stressor may interfere with adaptation. As defective adaptation to stress can enhance the probability to develop pathologies, we studied in adult male rats (n = 10/group) swimming behavior (struggling, immobility and mild swim) and physiological responses (ACTH, corticosterone and rectal temperature) to daily repeated exposure to forced swim (20 min, 13 d) at 25 or 36 °C (swim25 or swim36). Rats were repeatedly blood-sampled by tail-nick and hormones measured by radioimmunoassay. Some differences were observed between the two swim temperature groups after the first exposure to forced swim: (a) active behaviors were greater in swim25 than swim36 groups; (b) swim25 but not swim36 caused hypothermia; and (c) swim36 elicited the same ACTH response as swim25, but plasma corticosterone concentration was lower for swim36 at 30 min post-swim. After daily repeated exposure, adaptation in ACTH secretion was observed with swim36 already on day 4, whereas with swim25 adaptation was not observed until day 13 and was of lower magnitude. Nevertheless, after repeated exposure to swim25 a partial protection from hypothermia was observed and the two swim conditions resulted in progressive reduction of active behaviors. Thus, daily repeated swim at 25 °C impairs adaptation of the hypothalamic-pituitary-adrenal axis as compared to swim at 36 °C, supporting the hypothesis that certain physical components of predominantly emotional stressors can interfere with the process of adaptation.

Hypericum perforatum L. treatment restored bone mass changes in swimming stressed rats.

PubMed

Seferos, Nikos; Petrokokkinos, Loukas; Kotsiou, Antonia; Rallis, George; Tesseromatis, Christine

2016-01-01

Stress, via corticosteroids release, influences bone mass density. Hypericum perforatum (Hp) a traditional remedy possess antidepressive activity (serotonin reuptake inhibitor) and wound healing properties. Hp preparation contains mainly hypericin, hyperforin, hyperoside and flavonoids exerting oestrogen-mimetic effect. Cold swimming represents an experimental model of stress associating mental strain and corporal exhaustion. This study investigates the Hp effect on femur and mandible bone mass changes in rats under cold forced swimming procedure. 30 male Wistar rats were randomized into three groups. Group A was treated with Methanolic extract of Hp (Jarsin®) via gastroesophageal catheter, and was submitted to cold swimming stress for 10 min/daily. Group B was submitted to cold stress, since group C served as control. Experiment duration was 10 days. Haematocrite and serum free fatty acids (FFA) were estimated. Furthermore volume and specific weight of each bone as well as bone mass density via dual energy X-Ray absorptiometry (DEXA) were measured. Statistic analysis by t-test. Hp treatment restores the stress injuries. Adrenals and bone mass density regain their normal values. Injuries occurring by forced swimming stress in the rats are significantly improved by Hp treatment. Estrogen-like effects of Hp flavonoids eventually may act favorable in bone remodeling.

Central nervous system activity of the ethanol leaf extract of Sida acuta in rats.

PubMed

Ibironke, G F; Umukoro, A S; Ajonijebu, D C

2014-03-01

The study investigated the pharmacological effects of ethanol extract of Sida acuta leaves on central nervous system activities in mice. Adult male mice (18 - 25g) were used for the study. The extract was administered orally in male mice and evaluated in the following tests: forced swimming, tail suspension, formalin-induced paw licking, acetic acid--induced mouse writhing and apomorphine-induced stereotypy. The results revealed a reduction in the frequency of abdominal constrictions induced by acetic acid, decreased licking times in both phases of the formalin test, reduction in immobility times in forced swimming and tail suspension tests. However, the extract produced no effect on apomorphine-induced stereotyped behaviour. These results suggest that the ethanol extract of Sida acuta contains psychoactive substances with analgesic and antidepressant-like properties which may be beneficial in the management of pain.

Synthesis and Antidepressant Activity Profile of Some Novel Benzothiazole Derivatives.

PubMed

Demir Özkay, Ümide; Kaya, Ceren; Acar Çevik, Ulviye; Can, Özgür Devrim

2017-09-07

Within the scope of our new antidepressant drug development efforts, in this study, we synthesized eight novel benzothiazole derivatives 3a - 3h . The chemical structures of the synthesized compounds were elucidated by spectroscopic methods. Test compounds were administered orally at a dose of 40 mg/kg to mice 24, 5 and 1 h before performing tail suspension, modified forced swimming, and activity cage tests. The obtained results showed that compounds 3c , 3d , 3f - 3h reduced the immobility time of mice as assessed in the tail suspension test. Moreover, in the modified forced swimming tests, the same compounds significantly decreased the immobility, but increased the swimming frequencies of mice, without any alteration in the climbing frequencies. These results, similar to the results induced by the reference drug fluoxetine (20 mg/kg, po), indicated the antidepressant-like activities of the compounds 3c , 3d , 3f - 3h . Owing to the fact that test compounds did not induce any significant alteration in the total number of spontaneous locomotor activities, the antidepressant-like effects of these derivatives seemed to be specific. In order to predict ADME parameters of the synthesized compounds 3a - 3h , some physicochemical parameters were calculated. The ADME prediction study revealed that all synthesized compounds may possess good pharmacokinetic profiles.

Test-retest paradigm of the forced swimming test in female mice is not valid for predicting antidepressant-like activity: participation of acetylcholine and sigma-1 receptors.

PubMed

Su, Jing; Hato-Yamada, Noriko; Araki, Hiroaki; Yoshimura, Hiroyuki

2013-01-01

The forced swimming test (FST) in mice is widely used to predict the antidepressant activity of a drug, but information describing the immobility of female mice is limited. We investigated whether a prior swimming experience affects the immobility duration in a second FST in female mice and whether the test-retest paradigm is a valid screening tool for antidepressants. Female ICR mice were exposed to the FST using two experimental paradigms: a single FST and a double FST in which mice had experienced FST once 24 h prior to the second trail. The initial FST experience reliably prolonged immobility duration in the second FST. The antidepressants imipramine and paroxetine significantly reduced immobility duration in the single FST, but not in the double FST. Scopolamine and the sigma-1 (σ1) antagonist NE-100 administered before the second trial significantly prevented the prolongation of immobility. Neither a 5-HT1A nor a 5-HT2A receptor agonist affected immobility duration. We suggest that the test-retest paradigm in female mice is not adequate for predicting antidepressant-like activity of a drug; the prolongation of immobility in the double FST is modulated through acetylcholine and σ1 receptors.

Mice receiving infrared irradiation have a higher survival rate under forced swimming in cold.

PubMed

Tsai, Jui-Feng

2009-10-01

To explore the effect of infrared (IR) irradiation on the survival rates of mice under forced swimming in cold conditions. IR irradiation has been found to be beneficial for wound healing, tumor reduction, pain relief, and even against depression. However, whether the antidepressant effect of IR irradiation came from heat has remained unanswered. The goals of the study were originally aimed at using an animal model for depression to understand the relationship between the antidepressant effect of IR irradiation and hyperthermia as well as seasonality. Forty-four mice were housed in cages in a room subject to the outdoor temperature, and randomly assigned to the IR-treated group (n = 15), the heat-treated group (n = 14), and the control group (n = 15) during winter. The mice of the IR-treated group received whole-body IR irradiation for 60 min daily, while the heat-treated group received heat diffusion to reach the same temperature level. The control group received neither IR nor heat. All groups of mice underwent a forced swimming test weekly. Incidentally, two episodes of cold current occurred during the study period, and some mice died. The survival rates were compared pairwise against the control. The IR-treated group had a significantly reduced relative risk (p = 0.013) when compared with the control group, while the heat-treated group did not show any significant reduction (p = 0.087). There was no significant difference in body temperatures of the three groups before and after the irradiation. IR irradiation resulted in a significantly higher survival rate for mice that were concurrently subjected to cold and a forced swimming test. This result may be beyond the thermal effect.

Postnatal cocaine exposure: effects on behavior of rats in forced swim test.

PubMed

Magalhães, Ana; Tavares, Maria Amélia; de Sousa, Liliana

2002-06-01

Exposure to cocaine in early periods of postnatal life has adverse effects on behavior, namely, it induces the display of anxiety and fear-like behaviors that are associated with stress and depression. This study examined the effects of early developmental cocaine exposure in several categories of behavior observed in forced swim test. Male and female Wistar rats were given 15 mg/kg of cocaine hydrochloride/body weight/day, subcutaneously, in two daily doses, from postnatal day (PND) 1 to PND27. Controls were saline injected in the same protocol. In PND26-PND27, rats were placed in a swimming pool during 5 min in two sessions. The categories of behavior studied in this work included horizontal and vertical rotation, vibrissae clean, head clean, fast and slow swim, struggling, floating, sliding, diving, head-diving, and wagging head. Results showed differences in the frequencies of several behavioral categories that allowed the discrimination of the behaviors that may constitute "behavioral despair" indicators, as well as which behaviors are most affected by cocaine exposure. Cocaine groups were less active and more immobile than controls. These results suggest that postnatal exposure to cocaine can produce depression-like effects and affect the ability of these animals to cope with stress situations.

Mechanical design, fabrication, and test of biomimetic fish robot using LIPCA as artificial muscle

NASA Astrophysics Data System (ADS)

Wiguna, T.; Syaifuddin, M.; Park, Hoon C.; Heo, S.

2006-03-01

This paper presents a mechanical design, fabrication and test of biomimetic fish robot using the Lightweight Piezocomposite Curved Actuator (LIPCA). We have designed a mechanism for converting actuation of the LIPCA into caudal fin movement. This linkage mechanism consists of rack-pinion system and four-bar linkage. We also have tested four types of caudal fin in order to examine effect of different shape of caudal fin on thrust generation by tail beat. Subsequently, based on the caudal fin test, four caudal fins which resemble fish caudal fin shapes of ostraciiform, subcarangiform, carangiform and thunniform, respectively, are attached to the posterior part of the robotic fish. The swimming test using 300 V pp input with 1 Hz to 1.5 Hz frequency was conducted to investigate effect of changing tail beat frequency and shape of caudal fin on the swimming speed of the robotic fish. The maximum swimming speed was reached when the device was operated at its natural swimming frequency. At the natural swimming frequency 1 Hz, maximum swimming speeds of 1.632 cm/s, 1.776 cm/s, 1.612 cm/s and 1.51 cm/s were reached for ostraciiform-, subcarangiform-, carangiform- and thunniform-like caudal fins, respectively. Strouhal numbers, which are a measure of thrust efficiency, were calculated in order to examine thrust performance of the present biomimetic fish robot. We also approximated the net forward force of the robotic fish using momentum conservation principle.

11-β hydroxysteroid type 1 knockout mice display an antidepressant-like phenotype in the forced swim test.

PubMed

Slattery, David A; Uzunov, Doncho P; Cryan, John F

2016-02-01

11β-dehydroxysteroid dehydrogenase (HSD) types 1 and 2, enzymes are involved in the activation and inactivation of glucocorticoids in vivo, respectively. Indirect evidence implicates two enzymes in the aetiology of depression but no study has directly assessed the potential role of 11 β-HSD1 in animal tests. We assessed 11 β-HSD1 knockout mice in the forced swim test (FST), tail suspension test (TST) and for locomotor activity. Genetic ablation of the 11β-HSD1 gene results in an antidepressant-like phenotype in the FST; the most widely utilised animal test of antidepressant activity, but not in the related TST. This may be related to the different biological substrates underlying these tests. The decreased FST immobility was not due to alterations in general activity. Taken together these results suggest that 11β-HSD1 may play an important role in depression-related behaviours and further studies are necessary to fully characterise its role in such behaviour.

Antidepressant-like Responses to Lithium in Genetically Diverse Mouse Strains

PubMed Central

Can, Adem; Blackwell, Robert A.; Piantadosi, Sean C.; Dao, David T.; O’Donnell, Kelley C.; Gould, Todd D.

2011-01-01

A mood stabilizing and antidepressant response to lithium is only found in a subgroup of bipolar disorder and depression patients. Identifying strains of mice that are responsive and non-responsive to lithium may elucidate genomic and other biological factors that play a role in lithium responsiveness. Mouse strains were tested in the forced swim, tail suspension, and open field tests after acute and chronic systemic, and intracerebroventricular and chronic lithium treatments. Serum and brain lithium levels were measured. Three (129S6/SvEvTac, C3H/HeNHsd, C57BL/6J) of the eight inbred strains tested, and one (CD-1) of the three outbred strains, showed an antidepressant-like response in the forced swim test following acute systemic administration of lithium. The three responsive inbred strains, as well as the DBA/2J strain, were also responsive in the forced swim test after chronic administration of lithium. However, in the tail suspension test, acute lithium resulted in an antidepressant-like effect only in C3H/HeNHsd mice. Only C57BL/6J and DBA/2J were responsive in the tail suspension test after chronic administration of lithium. Intracerebroventricular lithium administration resulted in a similar response profile in BALB/cJ (non-responsive) and C57BL/6J (responsive) strains. Serum and brain lithium concentrations demonstrated that behavioral results were not due to differential pharmacokinetics of lithium in individual strains, suggesting that genetic factors likely regulate responsiveness to lithium. Our results indicate that responsiveness to lithium in tests of antidepressant efficacy varies among genetically diverse mouse strains. These results will assist in identifying genomic factors associated with lithium responsiveness and the mechanisms of lithium action. PMID:21306560

Antidepressant-like effects of Tagetes lucida Cav. in the forced swimming test.

PubMed

Guadarrama-Cruz, G; Alarcon-Aguilar, F J; Lezama-Velasco, R; Vazquez-Palacios, G; Bonilla-Jaime, H

2008-11-20

Tagetes lucida (Asteraceae), has been referred in Mexican traditional medicine for the treatment of different central nervous system (CNS) diseases, mainly depression. Nevertheless, the available scientific information about this species is scarce and there are no reports related to its possible effect on the CNS. In this work, the antidepressant-like effect of extract of Tagetes lucida was evaluated in rats, as well as its potential adverse effects on male sexual behavior (MSB). Antidepressant activity was studied using forced swimming test (FST), motor activity in the open-field test and on MSB in sexually experienced male. The aqueous extract of Tagetes lucida in doses of 5, 10, 50, 100 and 200mg/(kgday)(-1) were administered orally for 14 consecutive days and evaluated on day 14, 2h after the last dose treatment. Fluoxetine (10mg/(kgday)(-1), p.o.) was used as the control positive. The aqueous extract (10, 50, 100mg/(kgday)(-1)) significantly reduced immobility and increased swimming without affecting climbing behavior in the FST. These same doses were not able to modify neither the motor activity nor the MSB. These data indicate that the extract of Tagetes lucida possesses antidepressant-like properties in rats.

Forced swimming stress does not affect monoamine levels and neurodegeneration in rats.

PubMed

Abbas, Ghulam; Naqvi, Sabira; Mehmood, Shahab; Kabir, Nurul; Dar, Ahsana

2011-10-01

The current study was aimed to investigate the correlations between immobility time in the forced swimming test (FST, a behavioral indicator of stress level) and hippocampal monoamine levels (markers of depression), plasma adrenalin level (a peripheral marker of stress) as well as fluoro-jade C staining (a marker of neurodegeneration). Male Sprague-Dawley rats were subjected to acute, sub-chronic (7 d) or chronic (14 d) FSTs and immobility time was recorded. Levels of noradrenalin, serotonin and dopamine in the hippocampus, and adrenalin level in the plasma were quantified by high-performance liquid chromatography with electrochemical detection. Brain sections from rats after chronic forced swimming or rotenone treatment (3 mg/kg subcutaneously for 4 d) were stained with fluoro-jade C. The rats subjected to swimming stress (acute, sub-chronic and chronic) showed long immobility times [(214 +/- 5), (220 +/- 4) and (231 +/- 7) s, respectively], indicating that the animals were under stress. However, the rats did not exhibit significant declines in hippocampal monoamine levels, and the plasma adrenalin level was not significantly increased compared to that in unstressed rats. The rats that underwent chronic swimming stress did not manifest fluoro-jade C staining in brain sections, while degenerating neurons were evident after rotenone treatment. The immobility time in the FST does not correlate with markers of depression (monoamine levels) and internal stress (adrenalin levels and neurodegeneration), hence this parameter may not be a true indicator of stress level.

Ovariectomy results in inbred strain-specific increases in anxiety-like behavior in mice

PubMed Central

Schoenrock, Sarah Adams; Oreper, Daniel; Young, Nancy; Ervin, Robin Betsch; Bogue, Molly A.; Valdar, William; Tarantino, Lisa M.

2017-01-01

Women are at an increased risk for developing affective disorders during times of hormonal flux, including menopause when the ovaries cease production of estrogen. However, while all women undergo menopause, not all develop an affective disorder. Increased vulnerability can result from genetic predisposition, environmental factors and gene by environment interactions. In order to investigate interactions between genetic background and estrogen depletion, we performed bilateral ovariectomy, a surgical procedure that results in estrogen depletion and is thought to model the post-menopausal state, in a genetically defined panel of 37 inbred mouse strains. Seventeen days post-ovariectomy, we assessed behavior in two standard rodent assays of anxiety- and depressive-like behavior, the open field and forced swim tests. We detected a significant interaction between ovariectomy and genetic background on anxiety-like behavior in the open field. No strain specific effects of ovariectomy were observed in the forced swim assay. However, we did observe significant strain effects for all behaviors in both the open field and forced swim tests. This study is the largest to date to look at the effects of ovariectomy on behavior and provides evidence that ovariectomy interacts with genetic background to alter anxiety-like behavior in an animal model of menopause. PMID:27693591

The antidepressant- and anxiolytic-like effects following co-treatment with escitalopram and risperidone in rats.

PubMed

Kaminska, K; Rogoz, Z

2016-06-01

Several clinical reports have documented a beneficial effect of the addition of a low dose of risperidone to the ongoing treatment with antidepressants, in particular selective serotonin reuptake inhibitors (SSRI), in the treatment of drug-resistant depression and treatment-resistant anxiety disorders. In the present study, we investigated the effect of treatment with the antidepressant escitalopram (SSRI) given separately or jointly with a low dose of risperidone (an atypical antipsychotic) in the forced swim test and in the elevated plus-maze test in rats. The obtained results showed that escitalopram at doses of 2.5 or 5 mg/kg evoked antidepressant-like effect in the forced swim test. Moreover, risperidone at low doses (0.05 or 0.1 mg/kg) enhanced the antidepressant-like activity of escitalopram (1 mg/kg) in this test by increasing the swimming time and decreasing the immobility time in those animals. WAY 100635 (a serotonin 5-HT1A receptor antagonist) at a dose of 0.1 mg/kg abolished the antidepressant-like effect induced by co-administration of escitalopram and risperidone. The active behavior in that test did not reflect an increase in general activity, since the combined treatment with escitalopram and risperidone failed to enhance the exploratory activity of rats. In the following experiment, we showed that escitalopram (5 mg/kg) and mirtazapine (5 or 10 mg/kg) or risperidone (0.1 mg/kg) induced an anxiolytic-like effect in the elevated plus-maze test, and the combined treatment with an ineffective dose of risperidone (0.05 mg/kg) enhanced the anxiolytic-like effects of escitalopram (2.5 mg/kg) or mirtazapine (1 and 2.5 mg/kg) in this test. The obtained results suggest that risperidone applied at a low dose enhances the antidepressant-like activity of escitalopram in the forced swim test, and that 5-HT1A receptors may play some role in these effects. Moreover, a low dose of risperidone may also enhance the anxiolytic-like action of the studied antidepressants.

Sex-dependent effects of fluoxetine and triiodothyronine in the forced swim test in rats.

PubMed

Lifschytz, Tzuri; Shalom, Galit; Lerer, Bernard; Newman, Michael E

2006-02-01

The effects of triiodothyronine (T3) and fluoxetine, administered separately and combined, on behavior of male and female rats in the forced swim test, a procedure for screening antidepressant-like activity, were determined. There were no consistent effects of low doses of fluoxetine (5 mg/kg) or T3 (20 microg/kg), administered daily for 2 weeks. Fluoxetine administered daily at 10 mg/kg for 7 days reduced immobility and increased active behaviors in male rats, but had no effects in female rats. The effects of fluoxetine in male rats were not potentiated by T3. In female rats, T3 at 100 microg/kg given daily for 7 days decreased immobility and increased swimming when these were measured 72 h after the last injection, but not when measurements were performed at an earlier time point. These results provide some support from an animal model for the efficacy of T3 as antidepressant therapy in female patients, but do not provide support for the augmentation and acceleration effects seen clinically when T3 is used in conjunction with established antidepressants such as fluoxetine.

Mechanisms of force production during linear accelerations in bluegill sunfish Lepomis macrochirus

NASA Astrophysics Data System (ADS)

Tytell, Eric D.; Wise, Tyler N.; Boden, Alexandra L.; Sanders, Erin K.; Schwalbe, Margot A. B.

2016-11-01

In nature, fish rarely swim steadily. Although unsteady behaviors are common, we know little about how fish change their swimming kinematics for routine accelerations, and how these changes affect the fluid dynamic forces and the wake produced. To study force production during acceleration, particle image velocimetry was used to quantify the wake of bluegill sunfish Lepomis macrochirus and to estimate the pressure field during linear accelerations and steady swimming. We separated "steady" and "unsteady" trials and quantified the forward acceleration using inertial measurement units. Compared to steady sequences, unsteady sequences had larger accelerations and higher body amplitudes. The wake consisted of single vortices shed during each tail movement (a '2S' wake). The structure did not change during acceleration, but the circulation of the vortices increased, resulting in larger forces. A fish swimming unsteadily produced significantly more force than the same fish swimming steadily, even when the accelerations were the same. This increase is likely due to increased added mass during unsteady swimming, as a result of the larger body amplitude. Pressure estimates suggest that the increase in force is correlated with more low pressure regions on the anterior body. This work was supported by ARO W911NF-14-1-0494 and NSF RCN-PLS 1062052.

Consequences of thermal acclimation for the mating behaviour and swimming performance of female mosquito fish.

PubMed

Wilson, Robbie S; Condon, Catriona H L; Johnston, Ian A

2007-11-29

The mating system of eastern mosquito fish (Gambusia holbrooki) is dominated by male sexual coercion, where all matings are forced and females never appear to cooperate and actively avoid all attempts. Previous research has shown that male G. holbrooki offer a model system for examining the benefits of reversible thermal acclimation for reproductive success, but examining the benefits to female avoidance behaviour has been difficult. In this study, we examined the ability of non-male-deprived female G. holbrooki to avoid forced-coercive matings following acclimation to either 18 or 30 degrees C for six weeks (12h light:12h dark photoperiod). Thermal acclimation of burst and sustained swimming performance was also assessed, as these traits are likely to underlie their ability to avoid forced matings. There was no influence of thermal acclimation on the burst swimming performance of female G. holbrooki over the range 18-30 degrees C; however, sustained swimming performance was significantly lower in the warm- than the cool-acclimation group. For mating behaviour, we tested the hypothesis that acclimation would enhance the ability of female G. holbrooki to avoid forced matings at their host acclimation temperature relative to females acclimated to another environment. However, our hypothesis was not supported. The rate of copulations was almost three times greater for females acclimated to 30 degrees C than 18 degrees C when tested at 30 degrees C, indicating that they possess the ability to alter their avoidance behaviour to 'allow' more copulations in some environments. Coupled with previous studies, female G. holbrooki appear to have greater control on the outcome of coercive mating attempts than previously considered and can alter their propensity to receive forced matings following thermal acclimation. The significance of this change in female mating-avoidance behaviours with thermal acclimation remains to be explored.

Rodent models of depression: forced swim and tail suspension behavioral despair tests in rats and mice.

PubMed

Castagné, Vincent; Moser, Paul; Roux, Sylvain; Porsolt, Roger D

2011-04-01

The development of antidepressants requires simple rodent behavioral tests for initial screening before undertaking more complex preclinical tests and clinical evaluation. Presented in the unit are two widely used screening tests used for antidepressants, the forced swim (also termed behavioral despair) test in the rat and mouse, and the tail suspension test in the mouse. These tests have good predictive validity and allow rapid and economical detection of substances with potential antidepressant-like activity. The behavioral despair and the tail suspension tests are based on the same principle: measurement of the duration of immobility when rodents are exposed to an inescapable situation. The majority of clinically used antidepressants decrease the duration of immobility. Antidepressants also increase the latency to immobility, and this additional measure can increase the sensitivity of the behavioral despair test in the mouse for certain classes of antidepressant. Testing of new substances in the behavioral despair and tail suspension tests allows a simple assessment of their potential antidepressant activity by the measurement of their effect on immobility. © 2011 by John Wiley & Sons, Inc.

Interactions between internal forces, body stiffness, and fluid environment in a neuromechanical model of lamprey swimming.

PubMed

Tytell, Eric D; Hsu, Chia-Yu; Williams, Thelma L; Cohen, Avis H; Fauci, Lisa J

2010-11-16

Animal movements result from a complex balance of many different forces. Muscles produce force to move the body; the body has inertial, elastic, and damping properties that may aid or oppose the muscle force; and the environment produces reaction forces back on the body. The actual motion is an emergent property of these interactions. To examine the roles of body stiffness, muscle activation, and fluid environment for swimming animals, a computational model of a lamprey was developed. The model uses an immersed boundary framework that fully couples the Navier-Stokes equations of fluid dynamics with an actuated, elastic body model. This is the first model at a Reynolds number appropriate for a swimming fish that captures the complete fluid-structure interaction, in which the body deforms according to both internal muscular forces and external fluid forces. Results indicate that identical muscle activation patterns can produce different kinematics depending on body stiffness, and the optimal value of stiffness for maximum acceleration is different from that for maximum steady swimming speed. Additionally, negative muscle work, observed in many fishes, emerges at higher tail beat frequencies without sensory input and may contribute to energy efficiency. Swimming fishes that can tune their body stiffness by appropriately timed muscle contractions may therefore be able to optimize the passive dynamics of their bodies to maximize peak acceleration or swimming speed.

Overexpression of Reelin prevents the manifestation of behavioral phenotypes related to schizophrenia and bipolar disorder.

PubMed

Teixeira, Cátia M; Martín, Eduardo D; Sahún, Ignasi; Masachs, Nuria; Pujadas, Lluís; Corvelo, André; Bosch, Carles; Rossi, Daniela; Martinez, Albert; Maldonado, Rafael; Dierssen, Mara; Soriano, Eduardo

2011-11-01

Despite the impact of schizophrenia and mood disorders, which in extreme cases can lead to death, recent decades have brought little progress in the development of new treatments. Recent studies have shown that Reelin, an extracellular protein that is critical for neuronal development, is reduced in schizophrenia and bipolar disorder patients. However, data on a causal or protective role of Reelin in psychiatric diseases is scarce. In order to study the direct influence of Reelin's levels on behavior, we subjected two mouse lines, in which Reelin levels are either reduced (Reelin heterozygous mice) or increased (Reelin overexpressing mice), to a battery of behavioral tests: open-field, black-white box, novelty-suppressed-feeding, forced-swim-test, chronic corticosterone treatment followed by forced-swim-test, cocaine sensitization and pre-pulse inhibition (PPI) deficits induced by N-methyl-D-aspartate (NMDA) antagonists. These tests were designed to model some aspects of psychiatric disorders such as schizophrenia, mood, and anxiety disorders. We found no differences between Reeler heterozygous mice and their wild-type littermates. However, Reelin overexpression in the mouse forebrain reduced the time spent floating in the forced-swim-test in mice subjected to chronic corticosterone treatment, reduced behavioral sensitization to cocaine, and reduced PPI deficits induced by a NMDA antagonist. In addition, we demonstrate that while stress increased NMDA NR2B-mediated synaptic transmission, known to be implicated in depression, Reelin overexpression significantly reduced it. Together, these results point to the Reelin signaling pathway as a relevant drug target for the treatment of a range of psychiatric disorders.

The Effect of Gentle Handling on Depressive-Like Behavior in Adult Male Mice: Considerations for Human and Rodent Interactions in the Laboratory

PubMed Central

Lane, Christina; Torres, Julio; Flinn, Jane

2018-01-01

Environmental factors play a significant role in well-being of laboratory animals. Regulations and guidelines recommend, if not require, that stressors such as bright lighting, smells, and noises are eliminated or reduced to maximize animal well-being. A factor that is often overlooked is handling and how researchers interact with their animals. Researchers, lab assistants, and husbandry staff in animal facilities may use inconsistent handling methods when interacting with rodents, but humans should be considered a part of the animal's social environment. This study examined the effects of different handling techniques on depressive-like behavior, measured by the Porsolt forced swim test, in adult C57BL/6J male mice. The same two researchers handled the mice in a gentle, aggressive, or minimal (control) fashion over approximately two weeks prior to testing. The results demonstrated a beneficial effect of gentle handling: gentle handling reduced swimming immobility in the forced swim test compared to mice that were aggressively or minimally handled. We argue that gentle handling, rather than methodical handling, can foster a better relationship between the handlers and rodents. Although handling is not standardized across labs, consistent gentle handling allows for less challenging behavioral testing, better data collection, and overall improved animal welfare. PMID:29692869

The Effect of Gentle Handling on Depressive-Like Behavior in Adult Male Mice: Considerations for Human and Rodent Interactions in the Laboratory.

PubMed

Neely, Caroline; Lane, Christina; Torres, Julio; Flinn, Jane

2018-01-01

Environmental factors play a significant role in well-being of laboratory animals. Regulations and guidelines recommend, if not require, that stressors such as bright lighting, smells, and noises are eliminated or reduced to maximize animal well-being. A factor that is often overlooked is handling and how researchers interact with their animals. Researchers, lab assistants, and husbandry staff in animal facilities may use inconsistent handling methods when interacting with rodents, but humans should be considered a part of the animal's social environment. This study examined the effects of different handling techniques on depressive-like behavior, measured by the Porsolt forced swim test, in adult C57BL/6J male mice. The same two researchers handled the mice in a gentle, aggressive, or minimal (control) fashion over approximately two weeks prior to testing. The results demonstrated a beneficial effect of gentle handling: gentle handling reduced swimming immobility in the forced swim test compared to mice that were aggressively or minimally handled. We argue that gentle handling, rather than methodical handling, can foster a better relationship between the handlers and rodents. Although handling is not standardized across labs, consistent gentle handling allows for less challenging behavioral testing, better data collection, and overall improved animal welfare.

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

Involvement of monoaminergic systems in anxiolytic and antidepressive activities of the standardized extract of Cocos nucifera L.

PubMed

Lima, Eliane Brito Cortez; de Sousa, Caren Nádia Soares; Meneses, Lucas Nascimento; E Silva Pereira, Yuri Freitas; Matos, Natália Castelo Branco; de Freitas, Rayanne Brito; Lima, Nycole Brito Cortez; Patrocínio, Manoel Cláudio Azevedo; Leal, Luzia Kalyne Almeida Moreira; Viana, Glauce Socorro Barros; Vasconcelos, Silvânia Maria Mendes

2017-01-01

Extracts from the husk fiber of Cocos nucifera are used in folk medicine, but their actions on the central nervous system have not been studied. Here, the anxiolytic and antidepressant effects of the standardized hydroalcoholic extract of C. nucifera husk fiber (HECN) were evaluated. Male Swiss mice were treated with HECN (50, 100, or 200 mg/kg) 60 min before experiments involving the plus maze test, hole-board test, tail suspension test, and forced swimming test (FST). HECN was administered orally (p.o.) in acute and repeated-dose treatments. The forced swimming test was performed with dopaminergic and noradrenergic antagonists, as well as a serotonin release inhibitor. Administration of HECN in the FST after intraperitoneal (i.p.) pretreatment of mice with sulpiride (50 mg/kg), prazosin (1 mg/kg), or p-chlorophenylalanine (PCPA, 100 mg/kg) caused the actions of these three agents to be reversed. However, this effect was not observed after pretreating the animals with SCH23390 (15 µg/kg, i.p.) or yohimbine (1 mg/kg, i.p.) The dose chosen for HECN was 100 mg/kg, p.o., which increased the number of entries as well as the permanence in the open arms of the maze after acute and repeated doses. In both the forced swimming and the tail suspension tests, the same dose decreased the time spent immobile but did not disturb locomotor activity in an open-field test. The anxiolytic effect of HECN appears to be related to the GABAergic system, while its antidepressant effect depends upon its interaction with the serotoninergic, noradrenergic (α1 receptors), and dopaminergic (D2 dopamine receptors) systems.

Chronic fluoxetine treatment partly attenuates the long-term anxiety and depressive symptoms induced by MDMA ('Ecstasy') in rats.

PubMed

Thompson, Murray R; Li, Kong M; Clemens, Kelly J; Gurtman, Clint G; Hunt, Glenn E; Cornish, Jennifer L; McGregor, Iain S

2004-04-01

Use of the drug 3,4-methylenedioxymethamphetamine (MDMA, 'Ecstasy') can have long-term adverse effects on emotion in both humans and laboratory animals. The present study examined whether chronic treatment with the antidepressant drug fluoxetine could reverse such effects. Male Wistar rats were briefly exposed to MDMA (4 x 5 mg/kg over 4 h) or vehicle on 2 consecutive days. Approximately 9-12 weeks later, half of the rats received a dose of approximately 6 mg/kg/day fluoxetine in their drinking water for a 5-week period. Fluoxetine administration reduced fluid intake and body weight in MDMA and vehicle pretreated rats. After several weeks of fluoxetine treatment, rats were assessed on the social interaction test, the emergence test of anxiety and the forced swim model of depression. MDMA pretreated rats showed reduced social interaction, increased anxiety on the emergence test, and increased immobility and decreased active responses in the forced swim test. Fluoxetine treatment reversed MDMA-induced anxiety in the emergence test and depressive-like effects in the forced swim test, yet exhibited no effects on the social interaction test. MDMA pretreated rats had decreased 5-HT and 5-HIAA levels in limbic and cortical regions, and decreased density of serotonin transporter sites in the cortex. Fluoxetine treatment did not greatly affect 5-HT levels in MDMA pretreated rats, but significantly decreased 5-HIAA levels in all brain sites examined. Postmortem blood serum levels of fluoxetine and norfluoxetine did not differ in MDMA and vehicle pretreated rats. These results indicate that fluoxetine may provide a treatment option for some of the deleterious long-term effects resulting from MDMA exposure.

Water spray-induced grooming is negatively correlated with depressive behavior in the forced swimming test in rats.

PubMed

Shiota, Noboru; Narikiyo, Kimiya; Masuda, Akira; Aou, Shuji

2016-05-01

Rodents show grooming, a typical self-care behavior, under stress and non-stress conditions. Previous studies revealed that grooming under stress conditions such as the open-field test (OFT) or the elevated plus-maze test (EPM) is associated with anxiety, but the roles of grooming under non-stress conditions are not well understood. Here, we examined spray-induced grooming as a model of grooming under a non-stress condition to investigate the relationship between this grooming and depression-like behavior in the forced swim test (FST) and tail suspension test, and we compared spray-induced grooming with OFT- and EPM-induced grooming. The main finding was that the duration of spray-induced grooming, but not that of OFT/EPM-induced grooming, was negatively correlated with the duration of immobility in the FST, an index of depression-like behavior. The results suggest that spray-induced grooming is functionally different from the grooming in the OFT and EPM and is related to reduction of depressive behavior.

Post-activation Potentiation in Propulsive Force after Specific Swimming Strength Training.

PubMed

Barbosa, A C; Barroso, R; Andries, O

2016-04-01

We investigated whether a conditioning activity (8×12.5 m with 2.5 min-interval using both hand paddles and parachute) induced post-activation potentiation in swimming propulsive force and whether a swimmer's force level affected a post-activation potentiation response. 8 competitive swimmers (5 males and 3 females, age: 18.4±1.3 years; IPS=796±56) performed a 10 s maximum tethered swimming test 8 and 4 min before (the highest value was considered as PRE), and 2.5 and 6.5 min after (POST1 and POST2, respectively) the conditioning activity. Rate of force development was not affected, but peak force in POST1 (p=0.02) and impulse in both POST1 (p=0.007) and POST2 (p=0.004) were reduced. Possibly the conditioning activity induced greater fatigue than post-activation potentiation benefits. For instance, the number of repetitions might have been excessive, and rest intervals between the conditioning activity and POST1 and POST2 were possibly too short. There were positive correlations between PRE peak force and changes in peak force and rate of force development. Although conditioning activity was detrimental, positive correlations suggest that weaker swimmers experience a deterioration of performance more than the stronger ones. This conditioning activity is not recommended for swimmers with the current competitive level before a competitive event. © Georg Thieme Verlag KG Stuttgart · New York.

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.

Maternal Forced Swimming Reduces Cell Proliferation in the Postnatal Dentate Gyrus of Mouse Offspring

PubMed Central

Wasinski, Frederick; Estrela, Gabriel R.; Arakaki, Aline M.; Bader, Michael; Alenina, Natalia; Klempin, Friederike; Araújo, Ronaldo C.

2016-01-01

Physical exercise positively affects the metabolism and induces proliferation of precursor cells in the adult brain. Maternal exercise likewise provokes adaptations early in the offspring. Using a high-intensity swimming protocol that comprises forced swim training before and during pregnancy, we determined the effect of maternal swimming on the mouse offspring's neurogenesis. Our data demonstrate decreased proliferation in sublayers of the postnatal dentate gyrus in offspring of swimming mother at postnatal day (P) 8 accompanied with decreased survival of newly generated cells 4 weeks later. The reduction in cell numbers was predominantly seen in the hilus and molecular layer. At P35, the reduced amount of cells was also reflected by a decrease in the population of newly generated immature and mature neurons of the granule cell layer. Our data suggest that forced maternal swimming at high-intensity has a negative effect on the neurogenic niche development in postnatal offspring. PMID:27621701

Neurochemical changes underlying schizophrenia-related behavior in a modified forced swim test in mice.

PubMed

Wożniak, Monika; Cieślik, Paulina; Marciniak, Marcin; Lenda, Tomasz; Pilc, Andrzej; Wieronska, Joanna M

2018-06-15

The modified forced swim test (MFST) has excellent predictive validity for investigating the antipsychotic activity of drugs, with particular emphasis on their activity toward negative symptoms of schizophrenia. However, its face and construct validity are less understood. Therefore, in the present study, some biochemical changes within GABAergic and serotonergic neurotransmission that could be related to observed MK-801-induced disturbances and the activity of compounds active at those neurotransmitters were investigated. In biochemical experiments, mice were treated acutely or chronically with MK-801 (13 days, 0.4 mg/kg). Their brains were dissected and frontal cortices and hippocampi were taken for further analysis. The levels of neurotransmitters were investigated with HPLC, and the expression of surrogate markers of schizophrenia (5-HT 1A receptors, GAD 65 , and GAD 67 , at both protein and mRNA levels) was measured via western blotting and q RT-PCR. The modified forced swim test and locomotor activity were used to assess the activity of GABA B and 5-HT 1A -related compounds. Repeated MK-801 treatment (13 days, 0.4 mg/kg dose) led to decreases in the DOPAC/DA, 3MT/DA and HVA/DA metabolic ratios. Increased 5-HT 1A protein expression and decreased GAD 65 and GAD 67 protein expression was observed in both the cortex and hippocampus. mRNA levels for all proteins were decreased. The increased immobility in the forced swim test was reversed both by a GABA B agonist (SKF97541, 0.025 or 0.05 mg/kg), a positive allosteric modulator of GABA B receptor (racBHFF, 5 or 10 mg/kg) and by a 5-HT 1A agonist ((R)-(+)-8-OH-DPAT 0.01 or 0.025 mg/kg). Our research supports the hypothesis that changes in the levels of GABA and/or 5-HT 1A receptors may contribute to the schizophrenia-like phenotype, and GABAergic and serotonergic agents may be good candidates for treating negative symptoms of schizophrenia. Copyright © 2018. Published by Elsevier Inc.

Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats.

PubMed

Arndt, David L; Peterson, Christy J; Cain, Mary E

2015-01-01

Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST) is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC), standard (SC), or isolated (IC) conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p.) was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg) rats and EC-fluoxetine (20 mg/kg) rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression.

Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats

PubMed Central

Arndt, David L.; Peterson, Christy J.; Cain, Mary E.

2015-01-01

Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST) is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC), standard (SC), or isolated (IC) conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p.) was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg) rats and EC-fluoxetine (20 mg/kg) rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression. PMID:26154768

Simulation of swimming strings immersed in a viscous fluid flow

NASA Astrophysics Data System (ADS)

Huang, Wei-Xi; Sung, Hyung Jin

2006-11-01

In nature, many phenomena involve interactions between flexible bodies and their surrounding viscous fluid, such as a swimming fish or a flapping flag. The intrinsic dynamics is complicate and not well understood. A flexible string can be regarded as a one-dimensional flag model. Many similarities can be found between the flapping string and swimming fish, although different wake speed results in a drag force for the flapping string and a propulsion force for the swimming fish. In the present study, we propose a mathematical formulation for swimming strings immersed in a viscous fluid flow. Fluid motion is governed by the Navier-Stokes equations and a momentum forcing is added in order to bring the fluid to move at the same velocity with the immersed surface. A flexible inextensible string model is described by another set of equations with an additional momentum forcing which is a result of the fluid viscosity and the pressure difference across the string. The momentum forcing is calculated by a feedback loop. Simulations of several numerical examples are carried out, including a hanging string which starts moving under gravity without ambient fluid, a swinging string immersed in a quiescent viscous fluid, a string swimming within a uniform surrounding flow, and flow over two side-by-side strings. The numerical results agree well with the theoretical analysis and previous experimental observations. Further simulation of a swimming fish is under consideration.

A medicinal herb, Melissa officinalis L. ameliorates depressive-like behavior of rats in the forced swimming test via regulating the serotonergic neurotransmitter.

PubMed

Lin, Shih-Hang; Chou, Mei-Ling; Chen, Wei-Cheng; Lai, Yi-Syuan; Lu, Kuan-Hung; Hao, Cherng-Wei; Sheen, Lee-Yan

2015-12-04

Depression is a serious psychological disorder that causes extreme economic loss and social problems. However, the conventional medications typically cause side effects that result in patients opting to out of therapy. Lemon balm (Melissa officinalis L., MO) is an old and particularly reliable medicinal herb for relieving feelings of melancholy, depression and anxiety. The present study aims to investigate the antidepressant-like activity of water extract of MO (WMO) by evaluating its influence on the behaviors and the relevant neurotransmitters of rats performed to forced swimming test. Two phases of the experiment were conducted. In the acute model, rats were administered ultrapure water (control), fluoxetine, WMO, or the indicated active compound (rosmarinic acid, RA) three times in one day. In the sub-acute model, rats were respectively administered ultrapure water (control), fluoxetine, or three dosages of WMO once a day for 10 days. Locomotor activity and depression-like behavior were examined using the open field test and the forced swimming test, respectively. The levels of relevant neurotransmitters and their metabolites in the frontal cortex, amygdala, hippocampus, and striatum were analyzed by high performance liquid chromatography. In the acute model, WMO and RA significantly reduced depressive-like behavior but the type of related neurotransmitter could not be determined. The results indicated that the effect of WMO administration on the reduction of immobility time was associated with an increase in swimming time of the rats, indicative of serotonergic neurotransmission modulation. Chromatography data validated that the activity of WMO was associated with a reduction in the serotonin turnover rate. The present study shows the serotonergic antidepressant-like activity of WMO. Hence, WMO may offer a serotonergic antidepressant activity to prevent depression and to assist in conventional therapies. Copyright © 2015. Published by Elsevier Ireland Ltd.

B-type natriuretic peptide (BNP) serum levels in rats after forced repeated swimming stress.

PubMed

Hadzovic-Dzuvo, Almira; Valjevac, Amina; Avdagić, Nesina; Lepara, Orhan; Zaćiragić, Asija; Jadrić, Radivoj; Alajbegović, Jasmin; Prnjavorac, Besim

2011-02-01

To estimate the effects of forced repeated swimming stress on BNP serum levels in rats. Adult male Wistar rats weighting between 280-330 g were divided into two groups: control group (n = 8) and stress group (n = 8). Rats in the stress group were exposed to forced swimming stress daily, for 7 days. The rats were forced to swim in plastic tanks (90 cm wide, 120 cm deep) containing tap water (temperature ca. 25 degrees C). The depth of water was 40 cm. Duration of each swimming session progressively increased from 10 minutes on the first day to 40 minutes on days 6 and 7. Rats were sacrificed and blood was drawn from abdominal aorta for BNP analysis immediately after the last swimming session. B-type natriuretic serum level was determined by ELISA method using RAT BNP-32 kit (Phoenix Pharmaceutical Inc.). There was no statistically significant difference between mean BNP serum level in the stress group after the swimming period (0.81 +/- 0.14 ng/ml) as compared to the unstressed group of rats (0.8 +/- 0.08 ng/ml). After the swimming period mean body weight slightly decreased in the stress group in comparison with values before stress period (296.3 g vs. 272.8 g), but this difference was not statistically significant. The stress period had no influence on food intake in the stress rat group. The workload consisting of 40-minutes long swimming session is not sufficient to provoke BNP release from myocardium in rats.

Comparison of time-dependent effects of (+)-methamphetamine or forced swim on monoamines, corticosterone, glucose, creatine, and creatinine in rats.

PubMed

Herring, Nicole R; Schaefer, Tori L; Tang, Peter H; Skelton, Matthew R; Lucot, James P; Gudelsky, Gary A; Vorhees, Charles V; Williams, Michael T

2008-05-30

Methamphetamine (MA) use is a worldwide problem. Abusers can have cognitive deficits, monoamine reductions, and altered magnetic resonance spectroscopy findings. Animal models have been used to investigate some of these effects, however many of these experiments have not examined the impact of MA on the stress response. For example, numerous studies have demonstrated (+)-MA-induced neurotoxicity and monoamine reductions, however the effects of MA on other markers that may play a role in neurotoxicity or cell energetics such as glucose, corticosterone, and/or creatine have received less attention. In this experiment, the effects of a neurotoxic regimen of (+)-MA (4 doses at 2 h intervals) on brain monoamines, neostriatal GFAP, plasma corticosterone, creatinine, and glucose, and brain and muscle creatine were evaluated 1, 7, 24, and 72 h after the first dose. In order to compare MA's effects with stress, animals were subjected to a forced swim test in a temporal pattern similar to MA administration [i.e., (30 min/session) 4 times at 2 h intervals]. MA increased corticosterone from 1-72 h with a peak 1 h after the first treatment, whereas glucose was only increased 1 h post-treatment. Neostriatal and hippocampal monoamines were decreased at 7, 24, and 72 h, with a concurrent increase in GFAP at 72 h. There was no effect of MA on regional brain creatine, however plasma creatinine was increased during the first 24 h and decreased by 72 h. As with MA treatment, forced swim increased corticosterone more than MA initially. Unlike MA, forced swim reduced creatine in the cerebellum with no change in other brain regions while plasma creatinine was decreased at 1 and 7 h. Glucose in plasma was decreased at 7 h. Both MA and forced swim increase demand on energy substrates but in different ways, and MA has persistent effects on corticosterone that are not attributable to stress alone.

Comparison of time-dependent effects of (+)-methamphetamine or forced swim on monoamines, corticosterone, glucose, creatine, and creatinine in rats

PubMed Central

Herring, Nicole R; Schaefer, Tori L; Tang, Peter H; Skelton, Matthew R; Lucot, James P; Gudelsky, Gary A; Vorhees, Charles V; Williams, Michael T

2008-01-01

Background Methamphetamine (MA) use is a worldwide problem. Abusers can have cognitive deficits, monoamine reductions, and altered magnetic resonance spectroscopy findings. Animal models have been used to investigate some of these effects, however many of these experiments have not examined the impact of MA on the stress response. For example, numerous studies have demonstrated (+)-MA-induced neurotoxicity and monoamine reductions, however the effects of MA on other markers that may play a role in neurotoxicity or cell energetics such as glucose, corticosterone, and/or creatine have received less attention. In this experiment, the effects of a neurotoxic regimen of (+)-MA (4 doses at 2 h intervals) on brain monoamines, neostriatal GFAP, plasma corticosterone, creatinine, and glucose, and brain and muscle creatine were evaluated 1, 7, 24, and 72 h after the first dose. In order to compare MA's effects with stress, animals were subjected to a forced swim test in a temporal pattern similar to MA administration [i.e., (30 min/session) 4 times at 2 h intervals]. Results MA increased corticosterone from 1–72 h with a peak 1 h after the first treatment, whereas glucose was only increased 1 h post-treatment. Neostriatal and hippocampal monoamines were decreased at 7, 24, and 72 h, with a concurrent increase in GFAP at 72 h. There was no effect of MA on regional brain creatine, however plasma creatinine was increased during the first 24 h and decreased by 72 h. As with MA treatment, forced swim increased corticosterone more than MA initially. Unlike MA, forced swim reduced creatine in the cerebellum with no change in other brain regions while plasma creatinine was decreased at 1 and 7 h. Glucose in plasma was decreased at 7 h. Conclusion Both MA and forced swim increase demand on energy substrates but in different ways, and MA has persistent effects on corticosterone that are not attributable to stress alone. PMID:18513404

Influence of enrichment on behavioral and neurogenic effects of antidepressants in Wistar rats submitted to repeated forced swim test.

PubMed

Possamai, Fernanda; dos Santos, Juliano; Walber, Thais; Marcon, Juliana C; dos Santos, Tiago Souza; Lino de Oliveira, Cilene

2015-04-03

Repeated forced swimming test (rFST) may detect gradual effects of antidepressants in adult rats. Antidepressants, as enrichment, affected behavior and neurogenesis in rats. However, the influence of enrichment on behavioral and neurogenic effects of antidepressants is unknown. Here, effects of antidepressants on rFST and hippocampal neurogenesis were investigated in rats under enriched conditions. Behaviors of male Wistar rats, housed from weaning in standard (SE) or enriched environment (EE), were registered during rFST. The rFST consisted of 15min of swimming (pretest) followed by 5min of swimming in the first (test), seventh (retest 1) and fourteenth (retest 2) days after pretest. One hour before the test, rats received an intraperitoneal injection of saline (1ml/kg), fluoxetine (2.5mg/kg) or imipramine (2.5 or 5mg/kg). These treatments were performed daily until the day of the retest 2. After retest 2, rats were euthanized for the identification of markers for neurogenesis in the hippocampus. Fluoxetine or imipramine decreased immobility in retests 1 and 2, as compared to saline. EE abolished these differences. In EE, fluoxetine or imipramine (5mg/kg) reduced immobility time in retest 2, as compared to the test. Independent of the housing conditions, fluoxetine and imipramine (5mg/kg) increased the ratio of immature neurons per progenitor cell in the hippocampus. In summary, antidepressants or enrichment counteracted the high immobility in rFST. Enrichment changed the effects of antidepressants in rFST depending on the type, and the dose of a substance but failed to change neurogenesis in control or antidepressant treated-rats. Effects of antidepressants and enrichment on rFST seemed neurogenesis-independent. Copyright © 2014 Elsevier Inc. All rights reserved.

Evaluation of antidepressant like property of amisulpride per se and its comparison with fluoxetine and olanzapine using forced swimming test in albino mice.

PubMed

Pawar, Ganesh R; Agrawal, Rajendra P; Phadnis, Pradeep; Paliwal, Abhay; Vyas, Savita; Solanki, Pooja

2009-01-01

Amisulpride, an atypical antipsychotic was evaluated for antidepressant like activity in forced swimming test in Swiss albino mice. The effect of amisulpride was compared with that of fluoxetine, the standard antidepressant and olanzapine, another atypical antipsychotic claimed to have antidepressant like activity. Both acute and chronic studies were carried out. In both the studies, animals were divided into four groups (n = 8 each) and subjected to oral drug interventions as follows -- Group 1- control (distilled water, 1 mL/kg); Group 2- fluoxetine in a dose of 10 mg/kg 23.5, 5 and 1 h before the test; Group 3-amisulpride in a dose of 70 mg/kg 23.5, 5 and 1 h before the test; Group 4- olanzapine in a dose of 2 mg/kg 23.5, 5 and 1 h before the study. In the chronic study, the treatment was given daily for 28 days with last dose being given 2 h prior to the test. A time sampling method was used to score the behavioral activity in each group. Results of both the studies indicated that animals given amisulpride displayed significant improvement in swimming behavior (p < 0.01), while markedly reducing immobility as compared to control group (p <0.01). Fluoxetine also showed significant difference in activity as compared to amisulpride and olanzapine (p < 0.01). There was no statistically significant difference between amisulpride and olanzapine in terms of effect on immobility and swimming phases in albino mice (p > 0.05). We conclude that amisulpride per se has an antidepressant like activity comparable to that of olanzapine though the activity was significantly less than that of fluoxetine.

Computer assisted video analysis of swimming performance in a forced swim test: simultaneous assessment of duration of immobility and swimming style in mice selected for high and low swim-stress induced analgesia.

PubMed

Juszczak, Grzegorz R; Lisowski, Paweł; Sliwa, Adam T; Swiergiel, Artur H

2008-10-20

In behavioral pharmacology, two problems are encountered when quantifying animal behavior: 1) reproducibility of the results across laboratories, especially in the case of manual scoring of animal behavior; 2) presence of different behavioral idiosyncrasies, common in genetically different animals, that mask or mimic the effects of the experimental treatments. This study aimed to develop an automated method enabling simultaneous assessment of the duration of immobility in mice and the depth of body submersion during swimming by means of computer assisted video analysis system (EthoVision from Noldus). We tested and compared parameters of immobility based either on the speed of an object (animal) movement or based on the percentage change in the object's area between the consecutive video frames. We also examined the effects of an erosion-dilation filtering procedure on the results obtained with both parameters of immobility. Finally, we proposed an automated method enabling assessment of depth of body submersion that reflects swimming performance. It was found that both parameters of immobility were sensitive to the effect of an antidepressant, desipramine, and that they yielded similar results when applied to mice that are good swimmers. The speed parameter was, however, more sensitive and more reliable because it depended less on random noise of the video image. Also, it was established that applying the erosion-dilation filtering procedure increased the reliability of both parameters of immobility. In case of mice that were poor swimmers, the assessed duration of immobility differed depending on a chosen parameter, thus resulting in the presence or lack of differences between two lines of mice that differed in swimming performance. These results substantiate the need for assessing swimming performance when the duration of immobility in the FST is compared in lines that differ in their swimming "styles". Testing swimming performance can also be important in the studies investigating the effects of swim stress on other behavioral or physiological parameters because poor swimming abilities displayed by some lines can increase severity of swim stress, masking the between-line differences or the main treatment effects.

A pressure-based force and torque prediction technique for the study of fish-like swimming

PubMed Central

Dabiri, John O.; Lauder, George V.

2017-01-01

Many outstanding questions about the evolution and function of fish morphology are linked to swimming dynamics, and a detailed knowledge of time-varying forces and torques along the animal’s body is a key component in answering many of these questions. Yet, quantifying these forces and torques experimentally represents a major challenge that to date prevents a full understanding of fish-like swimming. Here, we develop a method for obtaining these force and torque data non-invasively using standard 2D digital particle image velocimetry in conjunction with a pressure field algorithm. We use a mechanical flapping foil apparatus to model fish-like swimming and measure forces and torques directly with a load cell, and compare these measured values to those estimated simultaneously using our pressure-based approach. We demonstrate that, when out-of-plane flows are relatively small compared to the planar flow, and when pressure effects sufficiently dominate shear effects, this technique is able to accurately reproduce the shape, magnitude, and timing of locomotor forces and torques experienced by a fish-like swimmer. We conclude by exploring of the limits of this approach and its feasibility in the study of freely-swimming fishes. PMID:29216264

Identification of multiple genetic loci in the mouse controlling immobility time in the tail suspension and forced swimming tests.

PubMed

Abou-Elnaga, Ahmed F; Torigoe, Daisuke; Fouda, Mohamed M; Darwish, Ragab A; Abou-Ismail, Usama A; Morimatsu, Masami; Agui, Takashi

2015-05-01

Depression is one of the most famous psychiatric disorders in humans in all over the countries and considered a complex neurobehavioral trait and difficult to identify causal genes. Tail suspension test (TST) and forced swimming test (FST) are widely used for assessing depression-like behavior and antidepressant activity in mice. A variety of antidepressant agents are known to reduce immobility time in both TST and FST. To identify genetic determinants of immobility duration in both tests, we analyzed 101 F2 mice from an intercross between C57BL/6 and DBA/2 strains. Quantitative trait locus (QTL) mapping using 106 microsatellite markers revealed three loci (two significant and one suggestive) and five suggestive loci controlling immobility time in the TST and FST, respectively. Results of QTL analysis suggest a broad description of the genetic architecture underlying depression, providing underpinnings for identifying novel molecular targets for antidepressants to clear the complex genetic mechanisms of depressive disorders.

Anthriscus nemorosa essential oil inhalation prevents memory impairment, anxiety and depression in scopolamine-treated rats.

PubMed

Bagci, Eyup; Aydin, Emel; Ungureanu, Eugen; Hritcu, Lucian

2016-12-01

Anthriscus nemorosa (Bieb.) Sprengel is used for medicinal purposes in traditional medicine around the world, including Turkey. Ethnobotanical studies suggest that Anthriscus essential oil could improve memory in Alzheimer's disease. The current study was hypothesized to investigate the beneficial effects of inhaled Anthriscus nemorosa essential oil on memory, anxiety and depression in scopolamine-treated rats. Anthriscus nemorosa essential oil was administered by inhalation in the doses of 1% and 3% for 21 continuous days and scopolamine (0.7mg/kg) was injected intraperitoneally 30min before the behavioral testing. Y-maze and radial arm-maze tests were used for assessing memory processes. Also, the anxiety and depressive responses were studied by elevated plus-maze and forced swimming tests. As expected, the scopolamine alone-treated rats exhibited the following: decrease the percentage of the spontaneous alternation in Y-maze test, increase the number of working and reference memory errors in radial arm-maze test, decrease of the exploratory activity, the percentage of the time spent and the number of entries in the open arm within elevated plus-maze test and decrease of swimming time and increase of immobility time within forced swimming test. However, dual scopolamine and Anthriscus nemorosa essential oil-treated rats showed significant improvement of memory formation and exhibited anxiolytic- and antidepressant-like effects in scopolamine-treated rats. These results suggest that Anthriscus nemorosa essential oil inhalation can prevent scopolamine-induced memory impairment, anxiety and depression. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Assessment of the effect of prolonged forced swimming on CD-1 mice sperm morphology with and without antioxidant supplementation.

PubMed

Rodriguez, I; Diaz, A; Vaamonde, D

2016-04-01

As physical exercise has been shown to negatively affect sperm morphology, this study was undertaken to assess the effect of a 3-min forced swimming protocol during 50 days, with and without administration of antioxidants [N-acetylcysteine (NAC) and trans-resveratrol], on sperm morphology in CD-1 mice. Forty-four 13-week-old CD-1 mice were randomly allocated to four different groups: mice not submitted to exercise, control group (CG), mice submitted to swimming without administration of antioxidants (EX), mice submitted to swimming that received trans-resveratrol supplementation [exercise group (EX)+Resv] and mice submitted to swimming exercise that received NAC supplementation (EX+NAC). The EX showed 30.5% of spermatozoa with normal morphology, showing significant differences with regard to the CG, which showed 58.5%. The groups receiving antioxidant supplements showed significantly higher percentages of spermatozoa with normal morphology in comparison with the EX group (EX+Resv: 64.1%, EX+NAC: 48.2%). The imposed model of forced swimming caused alterations in sperm morphology. The antioxidants employed seem to be suitable antioxidants for avoiding exercise-associated sperm morphology anomalies in prolonged forced swimming exercise. Trans-resveratrol has proven to be more efficient for this purpose. © 2015 Blackwell Verlag GmbH.

The hydrodynamics of linear accelerations in bluegill sunfish, Lepomis macrochirus

NASA Astrophysics Data System (ADS)

Wise, Tyler; Boden, Alex; Schwalbe, Margot; Tytell, Eric

2015-11-01

As fish swim, their body interacts with the fluid around them in order to generate thrust. In this study, we examined the hydrodynamics of linear acceleration by bluegill sunfish, Lepomis macrochirus, which swims using a carangiform mode. Carangiform swimmers primarily use their caudal fin and posterior body for propulsion, which is different from anguilliform swimmers, like eels, that undulate almost their whole body to swim. Most previous studies have examined steady swimming, but few have looked at linear accelerations, even though most fish do not often swim steadily. During steady swimming, thrust and drag forces are balanced, which makes it difficult to separate the two, but during acceleration, thrust exceeds drag, making it easier to measure; this may reveal insights into how thrust is produced. This study used particle image velocimetry (PIV) to compare the structure of the wake during steady swimming and acceleration and to estimate the axial force. Axial force increased during acceleration, but the orientation of the vortices did not differ between steady swimming and acceleration, which is different than anguilliform swimmers, whose wakes change structure during acceleration. This difference may point to fundamental differences between the two swimming modes. This material is based upon work supported by the U. S. Army Research Office under grant number W911NF-14-1-0494.

Antidepressant-like effects of methanolic extract of Bacopa monniera in mice.

PubMed

Mannan, Abdul; Abir, Ariful Basher; Rahman, Rashidur

2015-09-25

Bacopa monniera has been used as a cure for various ailments that include anxiety, epileptic disorders, dementia, blood purifier, cough and rheumatism, and some important local uses of the plant are in dermatitis, anemia, diabetes, promote fertility and prevent miscarriage for many years in Bangladesh. According to this background, the aim of the study was to evaluate the antidepressant-like effect of the methanolic extract of B. monniera (MEBM) in different behavioral models such as forced swimming test (FST), measurement of locomotor activity test (MLAT) and tail suspension test (TST) on mice after two weeks treatment. Mice were divided into five groups (n = 5/group): control group (deionized water), standard group where Imipramine hydrochloride (30 mg/kg) was used as standard drug and three test groups where three doses of the methanolic extract of B. monniera (MEBM) (50, 100, and 200 mg/kg) was used for two weeks treatment. All the drug and test samples were administered via gavage through oral route. To assess the antidepressant-like effect of MEBM forced swimming test (FST), tail suspension test (TST) and measurement of locomotor activity test (MLAT) have been done in mice. The results showed that a strong and dose-dependent antidepressant effects in different mice models. The main findings of the MEBM significantly reduced the duration of immobility times in the forced swimming test (p < 0.001). Likewise, the extract significantly decreased the immobility time in the tail suspension test (p < 0.001). Moreover, we employed an additional measurement of locomotor activity test to check the motor stimulating activity of the MEBM. The extract also significantly increased the locomotion, rearing and defecation effects in comparison to the control group (p < 0.001). The present results clearly demonstrate that the methanolic extract of B. monniera possesses antidepressant-like activity in the animal behavioral models. The current study warrants further investigation into identification of the active compounds in herbal medicines, in particular extract of B. monniera with antidepressant-like effects.

Antifatigue Effect of Luteolin-6-C-Neohesperidoside on Oxidative Stress Injury Induced by Forced Swimming of Rats through Modulation of Nrf2/ARE Signaling Pathways.

PubMed

Duan, Fang-Fang; Guo, Ying; Li, Jing-Wan; Yuan, Ke

2017-01-01

Luteolin-6-C-neohesperidoside (LN) is a flavonoid isolated from moso bamboo leaf. This study was performed to evaluate the antifatigue effect of LN on a rat model undergoing the weight-loaded forced swimming test (FST). Briefly, male Sprague-Dawley rats (20-22 weeks old) were forced to undertake exhaustive swimming every other day for 3 weeks. Each swimming session was followed by the administration of distilled water, LN (25-75 mg/kg), or ascorbic acid (100 mg/kg) 1 h later. Oral administration of LN significantly improved exercise endurance; normalized alterations in energy metabolic markers; and decreased serum lactic acid, lactate dehydrogenase, and blood urea nitrogen levels of rats that underwent FST. Moreover, LN enhanced the activities of antioxidant enzymes and antioxidant capacity, as measured by enzyme activity assays, RT-PCR, and Western blotting, as well as decreasing the levels of proinflammatory cytokines such as tumor necrosis factor- α , interleukin-1 β (IL-1 β ), and IL-6 and increasing the level of anti-inflammatory (IL-10) in the liver and skeletal muscle. These results suggested that LN reduces both physical and mental effects of chronic fatigue, probably by attenuating oxidative stress injury and inflammatory responses in the liver and skeletal muscle. This study thus supports the use of LN in functional foods for antifatigue and antioxidant effects.

Absence of system xc- in mice decreases anxiety and depressive-like behavior without affecting sensorimotor function or spatial vision.

PubMed

Bentea, Eduard; Demuyser, Thomas; Van Liefferinge, Joeri; Albertini, Giulia; Deneyer, Lauren; Nys, Julie; Merckx, Ellen; Michotte, Yvette; Sato, Hideyo; Arckens, Lutgarde; Massie, Ann; Smolders, Ilse

2015-06-03

There is considerable preclinical and clinical evidence indicating that abnormal changes in glutamatergic signaling underlie the development of mood disorders. Astrocytic glutamate dysfunction, in particular, has been recently linked with the pathogenesis and treatment of mood disorders, including anxiety and depression. System xc- is a glial cystine/glutamate antiporter that is responsible for nonvesicular glutamate release in various regions of the brain. Although system xc- is involved in glutamate signal transduction, its possible role in mediating anxiety or depressive-like behaviors is currently unknown. In the present study, we phenotyped adult and aged system xc- deficient mice in a battery of tests for anxiety and depressive-like behavior (open field, light/dark test, elevated plus maze, novelty suppressed feeding, forced swim test, tail suspension test). Concomitantly, we evaluated the sensorimotor function of system xc- deficient mice, using motor and sensorimotor based tests (rotarod, adhesive removal test, nest building test). Finally, due to the presence and potential functional relevance of system xc- in the eye, we investigated the visual acuity of system xc- deficient mice (optomotor test). Our results indicate that loss of system xc- does not affect motor or sensorimotor function, in either adult or aged mice, in any of the paradigms investigated. Similarly, loss of system xc- does not affect basic visual acuity, in either adult or aged mice. On the other hand, in the open field and light/dark tests, and forced swim and tail suspension tests respectively, we could observe significant anxiolytic and antidepressive-like effects in system xc- deficient mice that in certain cases (light/dark, forced swim) were age-dependent. These findings indicate that, under physiological conditions, nonvesicular glutamate release via system xc- mediates aspects of higher brain function related to anxiety and depression, but does not influence sensorimotor function or spatial vision. As such, modulation of system xc- might constitute the basis of innovative interventions in mood disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

Antidepressant-like effect of rutin isolated from the ethanolic extract from Schinus molle L. in mice: evidence for the involvement of the serotonergic and noradrenergic systems.

PubMed

Machado, Daniele G; Bettio, Luis E B; Cunha, Mauricio P; Santos, Adair R S; Pizzolatti, Moacir G; Brighente, Inês M C; Rodrigues, Ana Lúcia S

2008-06-10

We have recently shown that the hexanic extract from leaves of Schinus molle produces antidepressant-like effects in the tail suspension test in mice. This study investigated the antidepressant-like effect of the ethanolic extract from aerial part of S. molle in the forced swimming test and tail suspension test in mice, two predictive models of depression. Moreover, we investigated the antidepressant potential of rutin, a flavonoid isolated from the ethanolic extract of this plant and the influence of the pretreatment with the inhibitors of serotonin or noradrenaline synthesis, p-chlorophenylalanine methyl ester (PCPA) and alpha-methyl-p-tyrosine (AMPT), respectively in the antidepressant-like effect of this flavonoid. The administration of the ethanolic extract produced a reduction in the immobility time in the tail suspension test (dose range 600-1000 mg/kg, p.o.), but not in the forced swimming test. It also produced a reduction in the ambulation in the open-field test in mice not previously habituated to the arena, but no effect in the locomotor activity in mice previously habituated to the open-field. The administration of rutin reduced the immobility time in the tail suspension test (0.3-3 mg/kg, p.o.), but not in the forced swimming test, without producing alteration in the locomotor activity. In addition, pretreatment of mice with PCPA (100 mg/kg, i.p., for 4 consecutive days) or AMPT (100 mg/kg, i.p.) prevented the anti-immobility effect of rutin (0.3 mg/kg, p.o.) in the tail suspension test. The results firstly indicated the antidepressant-like effect of the ethanolic extract of S. molle in the tail suspension test may be dependent on the presence of rutin that likely exerts its antidepressant-like effect by increasing the availability of serotonin and noradrenaline in the synaptic cleft.

The effects of central pro-and anti-inflammatory immune challenges on depressive-like behavior induced by chronic forced swim stress in rats.

PubMed

Pan, Yuqin; Lin, Wenjuan; Wang, Weiwen; Qi, Xiaoli; Wang, Donglin; Tang, Mingming

2013-06-15

Although increasing evidence demonstrates that both chronic stressors and inflammatory immune activation contribute to pathophysiology and behavioral alterations associated with major depression, little is known about the interaction effect of central inflammatory immune activation and stress on depressive-like behavior. Our previous work has shown that 14-day chronic forced swim stress induces significant depressive-like behavior. The present investigation assessed whether pro-inflammatory cytokine and anti-inflammatory cytokine challenges have differential interaction effect on depressive-like behavior induced by chronic forced swim stress in rats. The pro-inflammatory and anti-inflammatory immune challenges were achieved respectively by central administration of lipopolysaccharide (LPS), a pro-inflammatory cytokine inducer, and interleukin-10 (IL-10), an anti-inflammatory cytokine. It was found that either central LPS treatment alone or chronic forced swim stress alone significantly induced depressive-like behavior, including reduced body weight gain, reduced saccharin preference and reduced locomotor activity. However, there was no significant synergistic or additive effect of central LPS treatment and stress on depressive-like behavior. LPS treatment did not exacerbate the depressive-like behavior induced by forced swim stress. Nevertheless, IL-10 reversed depressive-like behavior induced by forced swim stress, a finding indicating that IL-10 has antidepressant effect on behavioral depression induced by stress. The present findings provide new insight into the complexity of the immunity-inflammation hypothesis of depression. Copyright © 2013 Elsevier B.V. All rights reserved.

Differential behavioral effects of the antidepressants reboxetine, fluoxetine, and moclobemide in a modified forced swim test following chronic treatment.

PubMed

Cryan, John F; Page, Michelle E; Lucki, Irwin

2005-11-01

The forced swim test (FST) is the most widely used model for assessing potential antidepressant activity in rodents following acute or short-term treatment. However, few studies have compared the effects of short- and long-term antidepressant treatment on behaviors in the test, despite the need to treat patients chronically to produce clinical effects. The current studies examined whether antidepressants from different classes produce different behavioral effects following short-term treatment and whether such effects change following administration for a longer duration. The effects of administering short-term (3 days) and long-term (14 days) treatments of antidepressants from three different chemical classes with distinct mechanisms of action via osmotic minipump were examined: the selective norepinephrine reuptake inhibitor reboxetine (10 and 60 mg kg(-1) day(-1)), the selective serotonin reuptake inhibitor fluoxetine (2.5 and 15 mg kg(-1) day(-1)), and the reversible inhibitor of monoamine oxidase moclobemide (2.5 and 15 mg kg(-1) day(-1)). All testing was carried out in a 15-min test with no preswim session in order to negate any confounding aspect of an induction procedure. The majority of antidepressant-sensitive behavioral changes were observed in the first 5 min of the test. The low dose of reboxetine failed to alter behavior in the test after 3 days but significantly decreased immobility and increased climbing behavior following administration for 14 days, whereas the high dose of reboxetine was equally effective following 3 and 14 days of treatment. In a similar fashion, the low dose of fluoxetine failed to alter behavior in the test following 3 days, but showed an augmented response on immobility and increased swimming following administration for 14 days. The high dose of fluoxetine was slightly more effective at reducing immobility following administration for 14 days than 3 days. The low dose of moclobemide decreased immobility and increased climbing behavior following treatment for 3 days, but increases in both swimming and climbing behaviors were measured following treatment for 14 days. Treatment with the high dose of moclobemide for 3 days decreased immobility and increased swimming, whereas treatment for 14 days significantly increased both active behaviors (swimming and climbing). Antidepressants from three different classes produce different effects on active behaviors in the FST. The effects of antidepressants were augmented following chronic administration for 14 days, especially when given at low doses. This suggests that modifications of the FST can be used to examine the onset of action of antidepressant agents produced by long-term administration.

Effects of periadolescent fluoxetine and paroxetine on elevated plus-maze, acoustic startle, and swimming immobility in rats while on and off-drug.

PubMed

Vorhees, Charles V; Morford, LaRonda R; Graham, Devon L; Skelton, Matthew R; Williams, Michael T

2011-10-05

Whether selective serotonin reuptake inhibitors (SSRIs) exposure during adolescent brain development causes lasting effects remains unresolved. Assess the effects of fluoxetine and paroxetine 60 days after adolescent exposure compared with when on-drug. Male Sprague-Dawley littermates (41 litters) were gavaged on postnatal days 33-53 with fluoxetine (3 or 10 mg/kg/day), paroxetine (3, 10 or, 17 mg/kg/day), or water; half were tested while on-drug (21 litters) and half after 60 days off-drug (20 litters). The highest dose of the drugs reduced body weight gain during treatment that rebounded 1 week post-treatment. On-drug, no significant group differences were found on elevated plus maze time-in-open, zone entries, or latency to first open entry; however, the high dose of paroxetine significantly reduced head-dips (N=20/group). No significant effects were found on-drug for acoustic startle response/prepulse inhibition (ASR/PPI) although a trend (p<0.10) was seen, which after combining dose levels, showed a significant increase in ASR amplitude for both fluoxetine and paroxetine (N=20-21/group). No differences on immobility time were seen in the Porsolt forced swim test or in plasma corticosterone at the end of forced swim (N-19-21/group). Off-drug, no effects were seen in the elevated plus maze (N=16/group), ASR/PPI (N=20/group), forced swim (N=19-20/group), or plasma corticosterone (N=19/group). At the doses tested, fluoxetine and paroxetine induced minor effects with drug on-board but no residual, long-term adverse effects in rats 60 days after drug discontinuation. The data provide no evidence that fluoxetine or paroxetine have long-term adverse effects on the behaviors measured here after adolescent to young adult exposure.

Unsteady computational fluid dynamics in front crawl swimming.

PubMed

Samson, Mathias; Bernard, Anthony; Monnet, Tony; Lacouture, Patrick; David, Laurent

2017-05-01

The development of codes and power calculations currently allows the simulation of increasingly complex flows, especially in the turbulent regime. Swimming research should benefit from these technological advances to try to better understand the dynamic mechanisms involved in swimming. An unsteady Computational Fluid Dynamics (CFD) study is conducted in crawl, in order to analyse the propulsive forces generated by the hand and forearm. The k-ω SST turbulence model and an overset grid method have been used. The main objectives are to analyse the evolution of the hand-forearm propulsive forces and to explain this relative to the arm kinematics parameters. In order to validate our simulation model, the calculated forces and pressures were compared with several other experimental and numerical studies. A good agreement is found between our results and those of other studies. The hand is the segment that generates the most propulsive forces during the aquatic stroke. As the pressure component is the main source of force, the orientation of the hand-forearm in the absolute coordinate system is an important kinematic parameter in the swimming performance. The propulsive forces are biggest when the angles of attack are high. CFD appears as a very valuable tool to better analyze the mechanisms of swimming performance and offers some promising developments, especially for optimizing the performance from a parametric study.

Reduced effectiveness of escitalopram in the forced swimming test is associated with increased serotonin clearance rate in food restricted rats

PubMed Central

France, CP; Li, J-X; Owens, WA; Koek, W; Toney, GM; Daws, LC

2012-01-01

Efficacy of antidepressant drugs is often limited. One of the limiting factors may be diet. This study shows that the effect of escitalopram in the forced swimming test is diminished in rats by food restriction that decreased body weight by 8%. The primary target for escitalopram is the serotonin (5-HT) transporter. Using high-speed chronoamperometry to measure 5-HT clearance in vivo in rats fed the same food restricted diet, the rate of 5-HT clearance from extracellular fluid in brain was dramatically increased. Increased 5-HT transporter function under conditions of dietary restriction might contribute to the decreased effect of escitalopram. These results suggest that diet plays an integral role in determining efficacy of antidepressant drugs, and might well generalize to other psychoactive drugs that impinge upon the 5-HT transporter. PMID:19419596

Theacrine, a special purine alkaloid with sedative and hypnotic properties from Cammelia assamica var. kucha in mice.

PubMed

Xu, Jie-Kun; Kurihara, Hiroshi; Zhao, Liang; Yao, Xin-Sheng

2007-01-01

The central nervous system activities of theacrine (1,3,7,9-tetramethyluric acid), a purine alkaloid which is abundantly present in Camellia assamica var. kucha, were investigated in ambulatory activity, pentobarbital-induced sleep and forced swimming test in mice, compared with two other purine alkaloids, caffeine and theobromine. Caffeine treatment led to a marked increase in the ambulatory activity accompanied with decreasing of the immobility time in forced swimming test at both 10 and 30 mg/kg. Under the same conditions, neither theacrine nor theobromine showed obvious excited efficacy. Both doses of theacrine could significantly prolong the sleeping time induced by pentobarbital, while caffeine and theobromine exhibited an inverted effect. These results indicated that theacrine possessed potent sedative and hypnotic properties and its central nervous system effects were different from those of caffeine and theobromine.

Relative Contribution of Arms and Legs in 30 s Fully Tethered Front Crawl Swimming

PubMed Central

Morouço, Pedro G.; Marinho, Daniel A.; Izquierdo, Mikel; Neiva, Henrique; Marques, Mário C.

2015-01-01

The relative contribution of arm stroke and leg kicking to maximal fully tethered front crawl swimming performance remains to be solved. Twenty-three national level young swimmers (12 male and 11 female) randomly performed 3 bouts of 30 s fully tethered swimming (using the whole body, only the arm stroke, and only the leg kicking). A load-cell system permitted the continuous measurement of the exerted forces, and swimming velocity was calculated from the time taken to complete a 50 m front crawl swim. As expected, with no restrictions swimmers were able to exert higher forces than that using only their arm stroke or leg kicking. Estimated relative contributions of arm stroke and leg kicking were 70.3% versus 29.7% for males and 66.6% versus 33.4% for females, with 15.6% and 13.1% force deficits, respectively. To obtain higher velocities, male swimmers are highly dependent on the maximum forces they can exert with the arm stroke (r = 0.77, P < 0.01), whereas female swimmers swimming velocity is more related to whole-body mean forces (r = 0.81, P < 0.01). The obtained results point that leg kicking plays an important role over short duration high intensity bouts and that the used methodology may be useful to identify strength and/or coordination flaws. PMID:26539511

Measurement of hydrodynamic force generation by swimming dolphins using bubble DPIV.

PubMed

Fish, Frank E; Legac, Paul; Williams, Terrie M; Wei, Timothy

2014-01-15

Attempts to measure the propulsive forces produced by swimming dolphins have been limited. Previous uses of computational hydrodynamic models and gliding experiments have provided estimates of thrust production by dolphins, but these were indirect tests that relied on various assumptions. The thrust produced by two actively swimming bottlenose dolphins (Tursiops truncatus) was directly measured using digital particle image velocimetry (DPIV). For dolphins swimming in a large outdoor pool, the DPIV method used illuminated microbubbles that were generated in a narrow sheet from a finely porous hose and a compressed air source. The movement of the bubbles was tracked with a high-speed video camera. Dolphins swam at speeds of 0.7 to 3.4 m s(-1) within the bubble sheet oriented along the midsagittal plane of the animal. The wake of the dolphin was visualized as the microbubbles were displaced because of the action of the propulsive flukes and jet flow. The oscillations of the dolphin flukes were shown to generate strong vortices in the wake. Thrust production was measured from the vortex strength through the Kutta-Joukowski theorem of aerodynamics. The dolphins generated up to 700 N during small amplitude swimming and up to 1468 N during large amplitude starts. The results of this study demonstrated that bubble DPIV can be used effectively to measure the thrust produced by large-bodied dolphins.

Silk amino acids improve physical stamina and male reproductive function of mice.

PubMed

Shin, Sunhee; Yeon, Seongho; Park, Dongsun; Oh, Jiyoung; Kang, Hyomin; Kim, Sunghyun; Joo, Seong Soo; Lim, Woo-Taek; Lee, Jeong-Yong; Choi, Kyung-Chul; Kim, Ki Yon; Kim, Seung Up; Kim, Jong-Choon; Kim, Yun-Bae

2010-01-01

The effects of a silk amino acid (SAA) preparation on the physical stamina and male reproductive function of mice were investigated. Eight-week-old male ICR mice (29-31 g) were orally administered SAA (50, 160 or 500 mg/kg) for 44 d during 30-min daily swimming exercise. The mice were subjected to a weight-loaded (5% of body weight) forced swimming on the 14th, 28th and 42nd day to determine maximum swimming time, and after a 2-d recovery period (treated with SAA without swimming exercise), parameters related to fatigue and reproductive function were analyzed from blood, muscles and reproductive organs. Repeated swimming exercise increased the maximum swimming time to some extent, in spite of a marked reduction in body weight gain, and SAA further enhanced the stamina in a dose-dependent manner. Forced swimming exercises increased blood parameters of tissue injury, but depleted blood glucose and tissue glycogen, which were substantially prevented by SAA treatment. In addition, SAA significantly reduced the muscular thiobarbituric acid-reactive substances and blood corticosterone content increased by forced swimming. Swimming exercise decreased the blood testosterone level, which was recovered by SAA, leading to enhanced sperm counts. These combined results indicate that SAA not only enhances physical stamina by minimizing damage to tissues, including muscles, as well as preventing energy depletion caused by swimming stress, but also improves male reproductive function by increasing testosterone and sperm counts.

Mechanics of undulatory swimming in a frictional fluid.

PubMed

Ding, Yang; Sharpe, Sarah S; Masse, Andrew; Goldman, Daniel I

2012-01-01

The sandfish lizard (Scincus scincus) swims within granular media (sand) using axial body undulations to propel itself without the use of limbs. In previous work we predicted average swimming speed by developing a numerical simulation that incorporated experimentally measured biological kinematics into a multibody sandfish model. The model was coupled to an experimentally validated soft sphere discrete element method simulation of the granular medium. In this paper, we use the simulation to study the detailed mechanics of undulatory swimming in a "granular frictional fluid" and compare the predictions to our previously developed resistive force theory (RFT) which models sand-swimming using empirically determined granular drag laws. The simulation reveals that the forward speed of the center of mass (CoM) oscillates about its average speed in antiphase with head drag. The coupling between overall body motion and body deformation results in a non-trivial pattern in the magnitude of lateral displacement of the segments along the body. The actuator torque and segment power are maximal near the center of the body and decrease to zero toward the head and the tail. Approximately 30% of the net swimming power is dissipated in head drag. The power consumption is proportional to the frequency in the biologically relevant range, which confirms that frictional forces dominate during sand-swimming by the sandfish. Comparison of the segmental forces measured in simulation with the force on a laterally oscillating rod reveals that a granular hysteresis effect causes the overestimation of the body thrust forces in the RFT. Our models provide detailed testable predictions for biological locomotion in a granular environment.

Mechanics of Undulatory Swimming in a Frictional Fluid

PubMed Central

Ding, Yang; Sharpe, Sarah S.; Masse, Andrew; Goldman, Daniel I.

2012-01-01

The sandfish lizard (Scincus scincus) swims within granular media (sand) using axial body undulations to propel itself without the use of limbs. In previous work we predicted average swimming speed by developing a numerical simulation that incorporated experimentally measured biological kinematics into a multibody sandfish model. The model was coupled to an experimentally validated soft sphere discrete element method simulation of the granular medium. In this paper, we use the simulation to study the detailed mechanics of undulatory swimming in a “granular frictional fluid” and compare the predictions to our previously developed resistive force theory (RFT) which models sand-swimming using empirically determined granular drag laws. The simulation reveals that the forward speed of the center of mass (CoM) oscillates about its average speed in antiphase with head drag. The coupling between overall body motion and body deformation results in a non-trivial pattern in the magnitude of lateral displacement of the segments along the body. The actuator torque and segment power are maximal near the center of the body and decrease to zero toward the head and the tail. Approximately 30% of the net swimming power is dissipated in head drag. The power consumption is proportional to the frequency in the biologically relevant range, which confirms that frictional forces dominate during sand-swimming by the sandfish. Comparison of the segmental forces measured in simulation with the force on a laterally oscillating rod reveals that a granular hysteresis effect causes the overestimation of the body thrust forces in the RFT. Our models provide detailed testable predictions for biological locomotion in a granular environment. PMID:23300407

Antidepressant-like effects of methanol extract of Hibiscus tiliaceus flowers in mice

PubMed Central

2012-01-01

Background Hibiscus tiliaceus L. (Malvaceae) is used in postpartum disorders. Our purpose was to examine the antidepressant, anxiolytic and sedative actions of the methanol extract of H. tiliaceus flowers using animal models. Methods Adult male Swiss albino mice were treated with saline, standard drugs or methanol extract of H. tiliaceus and then subjected to behavioral tests. The forced swimming and tail suspension tests were used as predictive animal models of antidepressant activity, where the time of immobility was considered. The animals were submitted to the elevated plus-maze and ketamine-induced sleeping time to assess anxiolytic and sedative activities, respectively. Results Methanol extract of H. tiliaceus significantly decreased the duration of immobility in both animal models of antidepressant activity, forced swimming and tail suspension tests. This extract did not potentiate the effect of ketamine-induced hypnosis, as determined by the time to onset and duration of sleeping time. Conclusion Our results indicate an antidepressant-like profile of action for the extract of Hibiscus tiliaceus without sedative side effect. PMID:22494845

Mice with Sort1 deficiency display normal cognition but elevated anxiety-like behavior.

PubMed

Ruan, Chun-Sheng; Yang, Chun-Rui; Li, Jia-Yi; Luo, Hai-Yun; Bobrovskaya, Larisa; Zhou, Xin-Fu

2016-07-01

Exposure to stressful life events plays a central role in the development of mood disorders in vulnerable individuals. However, the mechanisms that link mood disorders to stress are poorly understood. Brain-derived neurotrophic factor (BDNF) has long been implicated in positive regulation of depression and anxiety, while its precursor (proBDNF) recently showed an opposing effect on such mental illnesses. P75(NTR) and sortilin are co-receptors of proBDNF, however, the role of these receptors in mood regulation is not established. Here, we aimed to investigate the role of sortilin in regulating mood-related behaviors and its role in the proBDNF-mediated mood abnormality in mice. We found that sortilin was up-regulated in neocortex (by 78.3%) and hippocampus (by 111%) of chronically stressed mice as assessed by western blot analysis. These changes were associated with decreased mobility in the open field test and increased depression-like behavior in the forced swimming test. We also found that sortilin deficiency in mice resulted in hyperlocomotion in the open field test and increased anxiety-like behavior in both the open field and elevated plus maze tests. No depression-like behavior in the forced swimming test and no deficit in spatial cognition in the Morris water maze test were found in the Sort1-deficient mice. Moreover, the intracellular and extracellular levels of mature BDNF and proBDNF were not changed when sortilin was absent in vivo and in vitro. Finally, we found that both WT and Sort1-deficient mice injected with proBDNF in lateral ventricle displayed increased depression-like behavior in the forced swimming test but not anxiety-like behaviors in the open field and elevated plus maze tests. The present study suggests that sortilin functions as a negative regulator of mood performance and can be a therapeutic target for the treatment of mental illness. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

The antidepressant-like effect of ethynyl estradiol is mediated by both serotonergic and noradrenergic systems in the forced swimming test.

PubMed

Vega-Rivera, N M; López-Rubalcava, C; Estrada-Camarena, E

2013-10-10

17α-Ethynyl-estradiol (EE2, a synthetic steroidal estrogen) induces antidepressant-like effects in the forced swimming test (FST) similar to those induced by 5-HT and noradrenaline reuptake inhibitors (dual antidepressants). However, the precise mechanism of action of EE2 has not been studied. In the present study, the participation of estrogen receptors (ERs) and the serotonergic and the noradrenergic presynaptic sites in the antidepressant-like action of EE2 was evaluated in the FST. The effects of the ER antagonist ICI 182,780 (10 μg/rat; i.c.v.), the serotonergic and noradrenergic terminal destruction with 5,7-dihydroxytryptamine (5,7-DHT; 200 μg/rat, i.c.v.), and N-(2-chloro-ethyl)-N-ethyl-2-bromobenzylamine (DSP4; 10mg/kg, i.p.) were studied in ovariectomized rats treated with EE2 and subjected to the FST. In addition, the participation of α2-adrenergic receptors in the antidepressant-like action of EE2 was explored using the selective α2-receptor antagonist idazoxan (0.25, 0.5 and 1.0mg/kg, i.p.). EE2 induced an antidepressant-like action characterized by a decrease in immobility behavior with a concomitant increase in swimming and climbing behaviors. The ER antagonist, 5,7-DHT, DSP4, and idazoxan blocked the effects of EE2 on the immobility behavior, whereas ICI 182,780 and 5,7-DHT affected swimming behavior. The noradrenergic compound DSP4 altered climbing behavior, while Idazoxan inhibited the increase of swimming and climbing behaviors induced by EE2. Our results suggest that the antidepressant-like action of EE2 implies a complex mechanism of action on monoaminergic systems and estrogen receptors. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

Dopamine D2/D3 but not dopamine D1 receptors are involved in the rapid antidepressant-like effects of ketamine in the forced swim test.

PubMed

Li, Yan; Zhu, Zhuo R; Ou, Bao C; Wang, Ya Q; Tan, Zhou B; Deng, Chang M; Gao, Yi Y; Tang, Ming; So, Ji H; Mu, Yang L; Zhang, Lan Q

2015-02-15

Major depressive disorder is one of the most prevalent and life-threatening forms of mental illnesses. The traditional antidepressants often take several weeks, even months, to obtain clinical effects. However, recent clinical studies have shown that ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, exerts rapid antidepressant effects within 2h and are long-lasting. The aim of the present study was to investigate whether dopaminergic system was involved in the rapid antidepressant effects of ketamine. The acute administration of ketamine (20 mg/kg) significantly reduced the immobility time in the forced swim test. MK-801 (0.1 mg/kg), the more selective NMDA antagonist, also exerted rapid antidepressant-like effects. In contrast, fluoxetine (10 mg/kg) did not significantly reduced the immobility time in the forced swim test after 30 min administration. Notably, pretreatment with haloperidol (0.15 mg/kg, a nonselective dopamine D2/D3 antagonist), but not SCH23390 (0.04 and 0.1 mg/kg, a selective dopamine D1 receptor antagonist), significantly prevented the effects of ketamine or MK-801. Moreover, the administration of sub-effective dose of ketamine (10 mg/kg) in combination with pramipexole (0.3 mg/kg, a dopamine D2/D3 receptor agonist) exerted antidepressant-like effects compared with each drug alone. In conclusion, our results indicated that the dopamine D2/D3 receptors, but not D1 receptors, are involved in the rapid antidepressant-like effects of ketamine. Copyright © 2014 Elsevier B.V. All rights reserved.

Mouse strain differences in immobility and sensitivity to fluvoxamine and desipramine in the forced swimming test: analysis of serotonin and noradrenaline transporter binding.

PubMed

Sugimoto, Yumi; Kajiwara, Yoshinobu; Hirano, Kazufumi; Yamada, Shizuo; Tagawa, Noriko; Kobayashi, Yoshiharu; Hotta, Yoshihiro; Yamada, Jun

2008-09-11

Strain differences in immobility time in the forced swimming test were investigated in five strains of mice, namely, ICR, ddY, C57BL/6, DBA/2 and BALB/c mice. There were significant strain differences. The immobility times of ICR, ddY and C57BL/6 mice were longer than those of DBA/2 and BALB/c mice. Immobility times were not significantly related to locomotor activity in these strains. There were also differences in sensitivity to the selective serotonin reuptake inhibitor (SSRI) fluvoxamine. In ICR, ddY and C57BL/6 mice, fluvoxamine did not affect immobility time, while it reduced the immobility time of DBA/2 and BALB/c mice dose-dependently. The noradrenaline reuptake inhibitor desipramine decreased immobility time in all strains of mice. Serotonin (5-HT) transporter binding in the brains of all five strains of mice was also investigated. Analysis of 5-HT transporter binding revealed significant strain differences, being lower in DBA/2 and BALB/c mice than in other strains of mice. The amount of 5-HT transporter binding was correlated to baseline immobility time. However, there was no significant relation between noradrenaline transporter binding and immobility time. These results suggest that the duration of baseline immobility depends on the levels of 5-HT transporter binding, leading to apparent strain differences in immobility time in the forced swimming test. Furthermore, differences in 5-HT transporter binding may cause variations in responses to fluvoxamine.

Paternal environmental enrichment transgenerationally alters affective behavioral and neuroendocrine phenotypes.

PubMed

Yeshurun, Shlomo; Short, Annabel K; Bredy, Timothy W; Pang, Terence Y; Hannan, Anthony J

2017-03-01

Recent studies have demonstrated that paternal stress in rodents can result in modification of offspring behavior. Environmental enrichment, which enhances cognitive stimulation and physical activity, modifies various behaviors and reduces stress responses in adult rodents. We investigated the transgenerational influence of paternal environmental enrichment on offspring behavior and physiological stress response. Adult C57BL/6J male mice (F0) were exposed to either environmental enrichment or standard housing for four weeks and then pair-mated with naïve females. The F2 generation was generated using F1 male offspring. Male and female F1 and F2 offspring were tested for anxiety using the elevated-plus maze and large open field at 8 weeks of age. Depression-related behavior was assessed using the forced-swim test. Hypothalamic-pituitary-adrenal (HPA) axis function was determined by quantification of serum corticosterone and adrenocorticotropic hormone (ACTH) levels at baseline and after forced-swim stress. Paternal environmental enrichment was associated with increased body weights of male F1 and F2 offspring. There was no significant effect on F1 offspring anxiety and depression-related behaviors. There were no changes in anxiety-related behaviors in the F2 offspring, however these mice displayed a reduced latency to immobility in the forced-swim test. Furthermore, F2 females had significantly higher serum corticosterone levels post-stress, but not ACTH. These results show that paternal environmental enrichment exerts a sex-specific transgenerational impact on the behavioral and physiological response to stress. Our findings have implications for the modelling of psychiatric disorders in rodents. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hypericum grandifolium Choisy: a species native to Macaronesian Region with antidepressant effect.

PubMed

Sánchez-Mateo, C C; Bonkanka, C X; Rabanal, R M

2009-01-21

Various species of Hypericum genus have been used in the Canary Islands as sedative, diuretic, vermifuge, wound healing, antihysteric and antidepressant agent. Studies have shown that methanol extract of Hypericum grandifolium Choisy is active in tetrabenazine-induced ptosis and forced swimming tests. In the current study, the aqueous, butanol and chloroform fractions obtained from the methanol extract as well as three sub-fractions derived from the chloroform fraction were evaluated for their central nervous effects in mice, particularly their antidepressant activity. The central nervous effect of different fractions and sub-fractions of Hypericum grandifolium was evaluated in mice using various behavioural models including locomotor and muscle relaxant activity, forced swimming test, effect on normal body temperature, barbiturate-induced sleep, tetrabenazine-induced syndrome and 5-hydroxytryptohan-induced head twitches and syndrome. We found that the butanol and chloroform fractions and all sub-fractions showed an antidepressant effect in the forced swimming test, the chloroform fraction being the most active. They produced no effects or only a slight depression of locomotor activity. Chloroform fraction significantly increased the pentobarbital-induced sleeping time, produced a slight but significant hypothermia and antagonized tetrabenazine-induced ptosis, whereas the butanol fraction produced a slight potentiation of 5-HTP-induced head twitches and syndrome. The present results, together with previous pharmacological and phytochemical data, indicated that Hypericum grandifolium possess antidepressant-like effects in mice and that different constituents, such as the flavonoids and the benzophenone derivatives, could be responsible at least in part for the antidepressant effects observed for this species.

Effect of sildenafil on the activity of some antidepressant drugs and electroconvulsive shock treatment in the forced swim test in mice.

PubMed

Socała, Katarzyna; Nieoczym, Dorota; Wyska, Elżbieta; Wlaź, Piotr

2017-04-01

Sildenafil, a potent and selective inhibitor of phosphodiesterase type 5, is used clinically to treat erectile dysfunction and pulmonary arterial hypertension. It is often taken by patients suffering from depression and receiving antidepressant drug treatment. However, its influence on the efficacy of antidepressant treatment was not sufficiently studied. Therefore, the aim of the present study was to investigate the influence of sildenafil on the anti-immobility action of several antidepressant drugs (i.e., sertraline, fluvoxamine, citalopram, maprotiline, trazodone, and agomelatine) as well as on antidepressant-like effect of electroconvulsive stimulations in the forced swim test in mice. The obtained results showed that acute sildenafil treatment enhanced the antidepressant-like activity of all of the studied drugs. The observed effects were not due to the increase in locomotor activity. The interactions between sildenafil and sertraline, maprotiline, and trazodone were pharmacodynamic in nature, as sildenafil did not affect concentrations of these drugs neither in serum nor in brain tissue. Increased concentrations of fluvoxamine, citalopram, and agomelatine in brain tissue evoked by sildenafil co-administration suggest that pharmacokinetic interactions between sildenafil and these drugs are very likely. Sildenafil injected acutely did not alter the antidepressant-like efficacy of electroconvulsive stimulations in mice, as assessed in the forced swim test. Interestingly, repeated (14 days) administration of sildenafil decreased the anti-immobility action of the electroconvulsive stimulations. In conclusion, the present study shows that sildenafil may alter the effectiveness of antidepressant treatment. Further studies are warranted to better characterize the influence of sildenafil on the activity of antidepressant drugs and electroconvulsive therapy.

Participation of hippocampal nitric oxide synthase and soluble guanylate cyclase in the modulation of behavioral responses elicited by the rat forced swimming test.

PubMed

Sales, Amanda J; Hiroaki-Sato, Vinícius A; Joca, Sâmia R L

2017-02-01

Systemic or hippocampal administration of nitric oxide (NO) synthase inhibitors induces antidepressant-like effects in animals, implicating increased hippocampal levels of NO in the neurobiology of depression. However, the role played by different NO synthase in this process has not been clearly defined. As stress is able to induce neuroinflammatory mechanisms and trigger the expression of inducible nitric oxide synthase (iNOS) in the brain, as well as upregulate neuronal nitric oxide synthase (nNOS) activity, the aim of the present study was to investigate the possible differential contribution of hippocampal iNOS and nNOS in the modulation of the consequences of stress elicited by the forced swimming test. Male Wistar rats received intrahippocampal injections, immediately after the pretest or 1 h before the forced swimming test, of selective inhibitors of nNOS (N-propyl-L-arginine), iNOS (1400W), or sGC (ODQ), the main pharmacological target for NO. Stress exposure increased nNOS and phospho-nNOS levels at all time points, whereas iNOS expression was increased only 24 h after the pretest. All drugs induced an antidepressant-like effect. However, whereas the nNOS inhibitor was equally effective when injected at different times, the iNOS inhibitor was more effective 24 h after the pretest. These results suggest that hippocampal nNOS and iNOS contribute to increase in NO levels in response to stress, although with a differential time course after stress exposure.

The involvement of NMDA receptor/NO/cGMP pathway in the antidepressant like effects of baclofen in mouse force swimming test.

PubMed

Khan, Muhammad Imran; Ostadhadi, Sattar; Zolfaghari, Samira; Ejtemaei Mehr, Shahram; Hassanzadeh, Gholamreza; Dehpour, Ahmad-Reza

2016-01-26

In the current study, the involvement of N-methyl-d-aspartate receptor (NMDAR) and nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) system in the antidepressant-like effects of baclofen was evaluated by using animal model in forced swimming test. Followed by an open field test for the evaluation of locomotor activity, the immobility time for mice in force swimming test was recorded. Only the last four min was analyzed. Administration of Baclofen (0.5 and 1mg/kg, i.p.) reduced the immobility interval in the FST. Prior administration of l-arginine (750mg/kg, i.p.,) a nitric oxide synthase substrate or sildenafil (5mg/kg, i.p.) a phosphodiesterase 5 into mice suppressed the antidepressant-like activity of baclofen (1mg/kg, i.p.).Co-treatment of 7-nitroindazole (50mg/kg, i.p.,) an inhibitor of neuronal nitric oxide synthase, L-NAME (10mg/kg, i.p.,) a non-specific inhibitor of nitric oxide synthase or MK-801 (0.05mg/kg, i.p.) an NMDA receptor antagonist with subeffective dose of baclofen (0.1mg/kg, i.p.), reduced the immobility time in the FST as compared to the drugs when used alone. Co-administrated of lower doses of MK-801 (0.01mg/kg) or l-NAME (1mg/kg) failed to effect immobility time however, simultaneous administration of these two agents in same dose with subeffective dose of baclofen (0.1mg/kg, i.p.), minimized the immobility time in the FST. Thus, our results support the role of NMDA receptors and l-arginine-NO-GMP pathway in the antidepressant-like action of baclofen. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effects of swim stress and fluoxetine on 5-HT1A receptor gene expression and monoamine metabolism in the rat brain regions.

PubMed

Shishkina, G T; Kalinina, T S; Dygalo, N N

2012-07-01

Changes in gene expression of the brain serotonin (5-HT) 1A receptors may be important for the development and ameliorating depression, however identification of specific stimuli that activate or reduce the receptor transcriptional activity is far from complete. In the present study, the forced swim test (FST) exposure, the first stress session of which is already sufficient to induce behavioral despair in rats, significantly increased 5-HT1A receptor mRNA levels in the brainstem, frontal cortex, and hippocampus at 24 h. In the brainstem and frontal cortex, the elevation in the receptor gene expression after the second forced swim session was not affected following chronic administration of fluoxetine, while in the cortex, both control and FST values were significantly reduced in fluoxetine-treated rats. In contrast to untreated rats, no increase in hippocampal 5-HT1A receptor mRNA was observed in response to FST in rats chronically treated with fluoxetine. Metabolism of 5-HT (5-HIAA/5-HT) in the brainstem was significantly decreased by fluoxetine and further reduced by swim stress, showing a certain degree of independence of these changes on 5-HT1A receptor gene expression that was increased in this brain region only after the FST, but not after fluoxetine. FST exposure also decreased the brainstem dopamine metabolism, which was unexpectedly positively correlated with 5-HT1A receptor mRNA levels in the frontal cortex. Together, these data suggest that the effects of the forced swim stress as well as fluoxetine involve brain region-dependent alterations in 5-HT1A receptor gene transcription, some of which may be interrelated with concomitant changes in catecholamine metabolism.

Modeling and simulation of fish swimming with active muscles.

PubMed

Curatolo, Michele; Teresi, Luciano

2016-11-21

Our goal is to reproduce the key features of carangiform swimming by modeling muscle functioning using the notion of active distortions, thus emphasizing the kinematical role of muscle, the generation of movement, rather than the dynamical one, the production of force. This approach, already proposed to model the action of muscles in different contexts, is here tested again for the problem of developing an effective and reliable framework to model and simulate swimming. A proper undulatory movement of a fish-like body is reproduced by defining a pattern of distortions, tuned in both space and time, meant to model the muscles activation which produce the flexural motion of body fish; eventually, interactions with the surrounding water yields the desired thrust. Carangiform swimmers have a relatively inflexible anterior body section and a generally flat, flexible posterior section. Because of this configuration, undulations sent rearward along the body attain a significant amplitude only in the posterior section. We compare the performances of different swimming gaits, and we are able to find some important relations between key parameters such as frequencies, wavelength, tail amplitude, and the achieved swim velocity, or the generated thrust, which summarize the swimming performance. In particular, an interesting relation is found between the Strouhal number and the wavelength of muscles activation. We highlight the muscle function during fish locomotion describing the activation of muscles and the relation between the force production and the shortening-lengthening cycle of muscle. We found a great accordance between results and empirical relations, giving an implicit validation of our models. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antifatigue Effect of Luteolin-6-C-Neohesperidoside on Oxidative Stress Injury Induced by Forced Swimming of Rats through Modulation of Nrf2/ARE Signaling Pathways

PubMed Central

Duan, Fang-fang; Guo, Ying; Li, Jing-wan

2017-01-01

Luteolin-6-C-neohesperidoside (LN) is a flavonoid isolated from moso bamboo leaf. This study was performed to evaluate the antifatigue effect of LN on a rat model undergoing the weight-loaded forced swimming test (FST). Briefly, male Sprague-Dawley rats (20–22 weeks old) were forced to undertake exhaustive swimming every other day for 3 weeks. Each swimming session was followed by the administration of distilled water, LN (25–75 mg/kg), or ascorbic acid (100 mg/kg) 1 h later. Oral administration of LN significantly improved exercise endurance; normalized alterations in energy metabolic markers; and decreased serum lactic acid, lactate dehydrogenase, and blood urea nitrogen levels of rats that underwent FST. Moreover, LN enhanced the activities of antioxidant enzymes and antioxidant capacity, as measured by enzyme activity assays, RT-PCR, and Western blotting, as well as decreasing the levels of proinflammatory cytokines such as tumor necrosis factor-α, interleukin-1β (IL-1β), and IL-6 and increasing the level of anti-inflammatory (IL-10) in the liver and skeletal muscle. These results suggested that LN reduces both physical and mental effects of chronic fatigue, probably by attenuating oxidative stress injury and inflammatory responses in the liver and skeletal muscle. This study thus supports the use of LN in functional foods for antifatigue and antioxidant effects. PMID:28588747

Repeated exposure to two stressors in sequence demonstrates that corticosterone and paraventricular nucleus of the hypothalamus interleukin-1β responses habituate independently.

PubMed

Lovelock, D F; Deak, T

2017-09-01

A wide range of stress-related pathologies such as post-traumatic stress disorder are considered to arise from aberrant or maladaptive forms of stress adaptation. The hypothalamic-pituitary-adrenal (HPA) axis readily adapts to repeated stressor exposure, yet little is known about adaptation in neuroimmune responses to repeated or sequential stress challenges. In Experiment 1, rats were exposed to 10 days of restraint alone (60 minutes daily), forced swim alone (30 minutes daily) or daily sequential exposure to restraint (60 minutes) followed immediately by forced swim (30 minutes), termed sequential stress exposure. Habituation of the corticosterone (CORT) response occurred to restraint by 5 days and swim at 10 days, whereas rats exposed to sequential stress exposure failed to display habituation to the combined challenge. Experiment 2 compared 1 or 5 days of forced swim with sequential stress exposure and examined how each affected expression of several neuroimmune and cellular activation genes in the paraventricular nucleus of the hypothalamus (PVN), prefrontal cortex (PFC) and hippocampus (HPC). Sequential exposure to restraint and swim increased interleukin (IL)-1β in the PVN, an effect that was attenuated after 5 days. Sequential stress exposure also elicited IL-6 and tumour necrosis factor-α responses in the HPC and PFC, respectively, which did not habituate after 5 days. Experiment 3 tested whether prior habituation to restraint (5 days) would alter the IL-1β response evoked by swim exposure imposed immediately after the sixth day of restraint. Surprisingly, a history of repeated exposure to restraint attenuated the PVN IL-1β response after swim in comparison to acutely-exposed subjects despite an equivalent CORT response. Overall, these findings suggest that habituation of neuroimmune responses to stress proceeds: (i) independent of HPA axis habituation; (ii) likely requires more daily sessions of stress to develop; and (iii) IL-1β displays a greater tendency to habituate after repeated stress challenges compared to other stress-reactive cytokines. © 2017 British Society for Neuroendocrinology.

The Impact of Resistance Training on Swimming Performance: A Systematic Review.

PubMed

Crowley, Emmet; Harrison, Andrew J; Lyons, Mark

2017-11-01

The majority of propulsive forces in swimming are produced from the upper body, with strong correlations between upper body strength and sprint performance. There are significant gaps in the literature relating to the impact of resistance training on swimming performance, specifically the transfer to swimming performance. The aims of this systematic literature review are to (1) explore the transfer of resistance-training modalities to swimming performance, and (2) examine the effects of resistance training on technical aspects of swimming. Four online databases were searched with the following inclusion criteria: (1) journal articles with outcome measures related to swimming performance, and (2) competitive swimmers participating in a structured resistance-training programme. Exclusion criteria were (1) participants with a mean age <16 years; (2) untrained, novice, masters and paraplegic swimmers; (3) triathletes and waterpolo players; (4) swimmers with injuries or illness; and (5) studies of starts and turns specifically. Data were extracted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the Physiotherapy Evidence Database (PEDro) scale was applied. For optimal transfer, specific, low-volume, high-velocity/force resistance-training programmes are optimal. Stroke length is best achieved through resistance training with low repetitions at a high velocity/force. Resisted swims are the most appropriate training modality for improving stroke rate. Future research is needed with respect to the effects of long-term resistance-training interventions on both technical parameters of swimming and overall swimming performance. The results of such work will be highly informative for the scientific community, coaches and athletes.

Swimming-Induced Taste Aversion and Its Prevention by a Prior History of Swimming

ERIC Educational Resources Information Center

Masaki, Takahisa; Nakajima, Sadahiko

2004-01-01

In two experiments, the evidence showed that 20 min of forced swimming by rats caused aversion to a taste solution consumed before swimming. When one of two taste solutions (sodium saccharin or sodium chloride, counterbalanced across rats) was paired with swimming and the other was not, the rats' intakes of these two solutions showed less…

Ovarian and uterine alterations following forced swimming: An immunohistochemical study.

PubMed

Seyed Saadat, Seyedeh Nazanin; Mohammadghasemi, Fahimeh; Ebrahimi, Hannan; Rafati Sajedi, Hanieh; Chatrnour, Gelayol

2016-10-01

Physical exercise is known to be a stressor stimulus that leads to reproductive disruption. The aim of this study was to evaluate the effect of forced swimming on the uterus and ovaries in mice. Adult mice (N=24) were divided into the following three groups: A, control; B, swimming in water (10 o C); and C, swimming in water (23 o C). Swimmers swam for 5 min daily for 5 consecutive days/ wk during 2 wks. An enzyme linked immunosorbent assay was used to determine serum estradiol, follicle stimulating hormone (FSH) and testosterone levels. Immunohistochemistry was performed to study apoptotic cells or estrogen receptor (ER) expression in uterine epithelial cells and ovaries. ANOVA was used for statistical analysis. Swimming in both groups reduced the serum FSH and estradiol levels (p<0.01) without having a significant effect on the serum testosterone level or percentage of apoptosis in ovarian and uterine tissues (p<0.01) compared with controls. A significant reduction in the number of ERs in the uterus and ovaries, and secondary and graafian follicles were observed in groups B and C compared with controls (p<0.01); however the number of primordial and primary follicles were not significantly changed in the ovaries. Forced swimming of 2 wks duration reduces the serum levels of FSH and estradiol without having effects on apoptosis in the ovaries or uteri of mice. Over a long period of time, forced swimming may have an adverse effect on fertility.

Ovarian and uterine alterations following forced swimming: An immunohistochemical study

PubMed Central

Seyed Saadat, Seyedeh Nazanin; Mohammadghasemi, Fahimeh; Ebrahimi, Hannan; Rafati Sajedi, Hanieh; Chatrnour, Gelayol

2016-01-01

Background: Physical exercise is known to be a stressor stimulus that leads to reproductive disruption. Objective: The aim of this study was to evaluate the effect of forced swimming on the uterus and ovaries in mice. Materials and Methods: Adult mice (N=24) were divided into the following three groups: A, control; B, swimming in water (10oC); and C, swimming in water (23oC). Swimmers swam for 5 min daily for 5 consecutive days/ wk during 2 wks. An enzyme linked immunosorbent assay was used to determine serum estradiol, follicle stimulating hormone (FSH) and testosterone levels. Immunohistochemistry was performed to study apoptotic cells or estrogen receptor (ER) expression in uterine epithelial cells and ovaries. ANOVA was used for statistical analysis. Results: Swimming in both groups reduced the serum FSH and estradiol levels (p<0.01) without having a significant effect on the serum testosterone level or percentage of apoptosis in ovarian and uterine tissues (p<0.01) compared with controls. A significant reduction in the number of ERs in the uterus and ovaries, and secondary and graafian follicles were observed in groups B and C compared with controls (p<0.01); however the number of primordial and primary follicles were not significantly changed in the ovaries. Conclusion: Forced swimming of 2 wks duration reduces the serum levels of FSH and estradiol without having effects on apoptosis in the ovaries or uteri of mice. Over a long period of time, forced swimming may have an adverse effect on fertility. PMID:27921086

Elevation of synaptic protein is associated with the antidepressant-like effects of ferulic acid in a chronic model of depression.

PubMed

Liu, Ya-Min; Hu, Chun-Yue; Shen, Ji-Duo; Wu, Su-Hui; Li, Yu-Cheng; Yi, Li-Tao

2017-02-01

Ferulic acid is a hydroxycinnamic acid that widely presents in plant cell wall components. It has been demonstrated that ferulic acid can reverse depressive-like behaviors in both forced swimming test and tail suspension test. However, it is unclear whether chronic ferulic acid treatment can ameliorate the depressive-like behaviors in chronic unpredictable mild stress (CUMS). Because of the putative relationship between neurotrophic system and antidepressant-like activity, we also investigated the effects of chronic ferulic acid on the brain-derived neurotrophic factor (BDNF), postsynaptic protein PSD95, presynaptic protein synapsin I in both prefrontal cortex and hippocampus. The results showed that ferulic acid significantly alleviated CUMS-induced depressive-like behaviors in sucrose preference test and forced swimming test. In addition, ferulic acid significantly up-regulated the levels of BDNF, PSD95 and synapsin I in the prefrontal cortex and hippocampus. The present data indicated that ferulic acid exerted the antidepressant-like effects on behaviors by increasing neurotrophin-related synaptic protein levels in CUMS mice. Copyright © 2016. Published by Elsevier Inc.

Swim pressure on walls with curves and corners.

PubMed

Smallenburg, Frank; Löwen, Hartmut

2015-09-01

The concept of swim pressure quantifies the average force exerted by microswimmers on confining walls in nonequilibrium. Here we explore how the swim pressure depends on the wall curvature and on the presence of sharp corners in the wall. For active Brownian particles at high dilution, we present a coherent framework which describes the force and torque on passive particles of arbitrary shape, in the limit of large particles compared to the persistence length of the swimmer trajectories. The resulting forces can be used to derive, for example, the activity-induced depletion interaction between two disks, as well as to optimize the shape of a tracer particle for high swimming velocity. Our predictions are verifiable in experiments on passive obstacles exposed to a bath of bacteria or artificial microswimmers.

Swim pressure on walls with curves and corners

NASA Astrophysics Data System (ADS)

Smallenburg, Frank; Löwen, Hartmut

2015-09-01

The concept of swim pressure quantifies the average force exerted by microswimmers on confining walls in nonequilibrium. Here we explore how the swim pressure depends on the wall curvature and on the presence of sharp corners in the wall. For active Brownian particles at high dilution, we present a coherent framework which describes the force and torque on passive particles of arbitrary shape, in the limit of large particles compared to the persistence length of the swimmer trajectories. The resulting forces can be used to derive, for example, the activity-induced depletion interaction between two disks, as well as to optimize the shape of a tracer particle for high swimming velocity. Our predictions are verifiable in experiments on passive obstacles exposed to a bath of bacteria or artificial microswimmers.

The categorisation of swimming start performance with reference to force generation on the main block and footrest components of the Omega OSB11 start blocks.

PubMed

Slawson, Sian E; Conway, Paul P; Cossor, Jodi; Chakravorti, Nandini; West, Andrew A

2013-01-01

Work presented in this paper provides a methodology for categorising swimming start performance based on peak force production on the main block and footrest components of the Omega OSB11 starting block. A total of 46 elite British swimmers were tested, producing over 1000 start trials. Overwater cameras were synchronised to a specifically designed start block that allowed the measurement of force production via two sets of four, tri-axis, force transducers; one set in the main block and one in the footrest. Data were then analysed, segregating trials for gender. Each start was categorised, with respect to the peak force production in horizontal and vertical components, into one of nine categories. Three performance indicators, i.e. block time, take-off velocity and distance of entry, were used to assess whether differences in performance could be correlated with these categories. Results from these data suggest that swimmers generating higher than average peak forces were more likely to produce a better overall start performance than those who produced forces lower than the average, for this population of athletes.

[Influence of estradiol on tryptophan hydroxylase and 5-hydroxytryptamine content in raphe nuclei of rats under forced swimming stress].

PubMed

Yang, Fu-zhong; Wu, Yan; Zhang, Wei-guo; Cai, Yi-yun; Shi, Shen-xun

2010-07-20

To investigate the effect of estradiol (E2) on tryptophan hydroxylase (TPH) and 5-hydroxytryptamine (5-HT) content in raphe nuclei of rats under forced swimming stress and explore the role of estrogen and stress in disease mechanism of depression in women. At Week 3 post-ovariectomy, 35 ovariectomized (OVX) female SD rats were randomly divided into 5 groups (n = 7): non-stress group, control group, estradiol (E2) group and fluoxetine (FLX) group and E2 plus FLX group. Animals were administered with different drugs for 2 weeks. At Day 14, animals except those in the non-stress group were subjected to the 15 min forced swimming test (FST). At 2 hours post-FST, all animals including those in the non-stress group were perfused with 4% paraformaldehyde and brains removed for TPH and 5-HT immunofluorescence staining. We compared the content of TPH and 5-HT by observing and calculating the integrated optical density (IOD) of immunofluorescent-positive signals in raphe nuclei. (1) The IOD value of TPH- and 5-HT-positive region in raphe nuclei of rats in the control group was significantly lower than that of the non-stress group (P < 0.01); (2) the IOD value of TPH- and 5-HT-positive region in raphe nuclei of rats in the E2, FLX and E2 plus FLX groups was significantly higher than that in the control group (P < 0.05). Forced swimming stress can decrease the TPH and 5-HT content in raphe nuclei. Such changes can be prevented by a pre-administration of estradiol. Similar results are observed with antidepressant fluoxetine. These effects may underlie the role of estradiol and stress in the disease mechanism of depression in women.

A detailed analysis of open-field habituation and behavioral and neurochemical antidepressant-like effects in postweaning enriched rats.

PubMed

Brenes, Juan C; Padilla, Michael; Fornaguera, Jaime

2009-01-30

Our previous work has shown that male Sprague-Dawley rats reared in social isolation, standard housing and environmental enrichment differ in their spontaneous open-field activity and in some neurobehavioral depressive-like parameters. Here, we extended this evidence by using a shorter postweaning rearing period (1 month) and including additional evaluations. First, in order to obtain a better characterization of the exploratory strategies among rearing conditions we analyzed in detail the spontaneous activity at the first minute and during the 10-min session. Second, we asked whether the changes in open-field activity were related with basal anxiety levels in the elevated plus-maze. Third, behavior in the forced-swimming test was analyzed and afterward, the tissue levels of hippocampal norepinephrine and serotonin were assessed. The possible relationship between neurotransmitters and forced-swimming behavior were explored through correlation analyses. We found that rearing conditions (i) differed on locomotor habituation and on sensory-motor exploration at the first minute and during the 10-min session without modifying the plus-maze behavior; (ii) affected differentially the grooming time, its sequential components, and the relationship between grooming and locomotor parameters; (iii) modified forced-swimming behavior and the hippocampal concentration of norepinephrine, serotonin, and its turnover; and (iv) produced different correlation patterns between both neurotransmitters and forced-swimming behaviors. Overall, environmental enrichment accelerated open-field habituation and led to behavioral and neurochemical antidepressant-like effects. In contract, isolation rearing strongly impaired habituation and simple information processing, but showed marginal effects on depressive-like behavior and on hippocampal neurochemistry. The current results suggest that differential rearing is not only a useful procedure to study behavioral plasticity or rigidity in response to early experience, but also to modeling some developmental protective or risk factors underlying depressive disorders.

Paramecia Swim with a constant propulsion in Solutions of Varying Viscosity

NASA Astrophysics Data System (ADS)

Valles, James M., Jr.; Jung, Ilyong; Mickalide, Harry; Park, Hojin; Powers, Thomas

2012-02-01

Paramecia swim through the coordinated beating of the 1000's of cilia covering their body. We have measured the swimming speed of populations of Paramecium Caudatam in solutions of different viscosity, η, to see how their propulsion changes with increased drag. We have found the average instantaneous speed, V to decrease monotonically with increasing η. The product ηv is roughly constant over a factor of 7 change in viscosity suggesting that paramecia swim at constant propulsion force. The distribution of swimming speeds is Gaussian. The width appears proportional to the average speed implying that both fast and slow swimmers exert a constant propulsion. We discuss the possibility that this behavior implies that the body cilia beat at constant force with varying viscosity.

The folic acid combined with 17-β estradiol produces antidepressant-like actions in ovariectomized rats forced to swim.

PubMed

Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia; Olivera-López, Jorge I; Jaramillo, M Teresa

2011-01-15

Folic acid or 17-β estradiol produces antidepressant effects, either alone or combined with several antidepressants. However, the antidepressant-like actions of folic acid combined with 17-β estradiol in the forced swimming test (FST) have not been tested before. Thus, in the present study, ovariectomized female rats received folic acid (5.0 nmol/i.c.v., P<0.05; 10.0 nmol/ i.c.v., P<0.05; or 50mg/kg, P<0.05, p.o.; 75.0; mg/kg, P<0.05, p.o.), or fluoxetine (20.0mg/kg, P<0.05; 25.0mg/kg, P<0.05) or 17-β estradiol (10.0 μg/rat, P<0.05; 20.0 μg/rat, P<0.05) and they displayed reduced immobility by increasing swimming behavior when they were tested in the FST. Combination of subthreshold doses of folic acid (2.5 nmol/i.c.v.; or 25.0mg/kg, p.o.) with subthreshold doses of 17-β estradiol (5.0 μg/rat, P<0.05) or with subthreshold doses of fluoxetine (15.0mg/kg, P<0.05) produced antidepressant-like actions. Ketanserin was used to evaluate the participation of the drugs used in the serotonergic pathway; ketanserin cancelled the antidepressant-like actions of the several combinations used. In conclusion, folic acid alone or combined with estradiol or fluoxetine in the FST reduced immobility in the FST. These antidepressant-like actions probably were due to modifications of the serotonergic system since swimming behavior was increased and these effects were cancelled by ketanserin. Copyright © 2010 Elsevier Inc. All rights reserved.

Male rats with same-sex preference show higher immobility in the forced swim test, but similar effects of fluoxetine and desipramine than males that prefer females.

PubMed

Hernández, Alejandra; Fernández-Guasti, Alonso

2018-05-25

Sex preference in male rats is partly determined by the organizational action of estradiol. Thus, several paradigms have used aromatase inhibitors to manipulate sex preference. We recently showed that a subpopulation of male rats prenatally treated with letrozole (0.56 μg/kg, G10-G22), a non-steroidal third generation aromatase inhibitor, had same sex preference, female sexual behavior (including lordosis and proceptivity) and penile erections when exposed to other males. These males, in addition, displayed high levels of experimental anxiety in the plus maze test and were insensitive to the anxiogenic-like acute effect of FLX (10 mg/kg). The two main purposes of the present work were: a) to study the behavioral profile of males displaying same sex preference in the forced swim test (FST), and b) to analyze if the antidepressant-like effect of the subchronic treatment with FLX (10 mg/kg, 3 times) or desipramine (DMI, 10 mg/kg, 3 times) vary according to sex preference. Males treated prenatally with letrozole with same-sex preference showed more immobility and less active behaviors (swimming and climbing) in the FST than males with female preference. Subchronic treatment with FLX and DMI reduced immobility when compared to saline controls, while FLX increased swimming and DMI increased climbing behavior. Treatments were equally effective in males with preference for other males and those that preferred females. These results indicate that an association exists between prenatal letrozole treatment, same sex preference and immobility in the FST. Copyright © 2017. Published by Elsevier Inc.

A proposal for refining the forced swim test in Swiss mice.

PubMed

Costa, Ana Paula Ramos; Vieira, Cintia; Bohner, Lauren O L; Silva, Cristiane Felisbino; Santos, Evelyn Cristina da Silva; De Lima, Thereza Christina Monteiro; Lino-de-Oliveira, Cilene

2013-08-01

The forced swim test (FST) is a preclinical test to the screening of antidepressants based on rats or mice behaviours, which is also sensitive to stimulants of motor activity. This work standardised and validated a method to register the active and passive behaviours of Swiss mice during the FST in order to strength the specificity of the test. Adult male Swiss mice were subjected to the FST for 6 min without any treatment or after intraperitoneal injection of saline (0.1 ml/10 g), antidepressants (imipramine, desipramine, or fluoxetine, 30 mg/kg) or stimulants (caffeine, 30 mg/kg or apomorphine, 10mg/kg). The latency, frequency and duration of behaviours (immobility, swimming, and climbing) were scored and summarised in bins of 6, 4, 2 or 1 min. Parameters were first analysed using Principal Components Analysis generating components putatively related to antidepressant (first and second) or to stimulant effects (third). Antidepressants and stimulants affected similarly the parameters grouped into all components. Effects of stimulants on climbing were better distinguished of antidepressants when analysed during the last 4 min of the FST. Surprisingly, the effects of antidepressants on immobility were better distinguished from saline when parameters were scored in the first 2 min. The method proposed here is able to distinguish antidepressants from stimulants of motor activity using Swiss mice in the FST. This refinement should reduce the number of mice used in preclinical evaluation of antidepressants. Copyright © 2013 Elsevier Inc. All rights reserved.

GPR39 (zinc receptor) knockout mice exhibit depression-like behavior and CREB/BDNF down-regulation in the hippocampus.

PubMed

Młyniec, Katarzyna; Budziszewska, Bogusława; Holst, Birgitte; Ostachowicz, Beata; Nowak, Gabriel

2014-10-31

Zinc may act as a neurotransmitter in the central nervous system by activation of the GPR39 metabotropic receptors. In the present study, we investigated whether GPR39 knockout would cause depressive-like and/or anxiety-like behavior, as measured by the forced swim test, tail suspension test, and light/dark test. We also investigated whether lack of GPR39 would change levels of cAMP response element-binding protein (CREB),brain-derived neurotrophic factor (BDNF) and tropomyosin related kinase B (TrkB) protein in the hippocampus and frontal cortex of GPR39 knockout mice subjected to the forced swim test, as measured by Western-blot analysis. In this study, GPR39 knockout mice showed an increased immobility time in both the forced swim test and tail suspension test, indicating depressive-like behavior and displayed anxiety-like phenotype. GPR39 knockout mice had lower CREB and BDNF levels in the hippocampus, but not in the frontal cortex, which indicates region specificity for the impaired CREB/BDNF pathway (which is important in antidepressant response) in the absence of GPR39. There were no changes in TrkB protein in either structure. In the present study, we also investigated activity in the hypothalamus-pituitary-adrenal axis under both zinc- and GPR39-deficient conditions. Zinc-deficient mice had higher serum corticosterone levels and lower glucocorticoid receptor levels in the hippocampus and frontal cortex. There were no changes in the GPR39 knockout mice in comparison with the wild-type control mice, which does not support a role of GPR39 in hypothalamus-pituitary-adrenal axis regulation. The results of this study indicate the involvement of the GPR39 Zn(2+)-sensing receptor in the pathophysiology of depression with component of anxiety. © The Author 2015. Published by Oxford University Press on behalf of CINP.

Stress-related behavioral alterations accompanying cocaine toxicity: the effects of mixed opioid drugs.

PubMed

Hayase, T; Yamamoto, Y; Yamamoto, K

2000-12-01

The present study evaluated the effects of mixed opioid drugs on the severity of cocaine (COCA) toxicity by examining stress-related behavioral alterations in mice. In order to ascertain the strength of the stress, the continuous observation of the behavioral symptoms in the cage and the forced swimming test (Porsolt test) were performed in the COCA (75 mg/kg, i.p.)-treated groups, with or without the mixed mu-kappa receptor-related opioid drugs, buprenorphine (BUP) and pentazocine (PEN). Using the high-sensitivity activity measuring instrument Supermex, both the spontaneous behaviors in the cage and the forced swimming behaviors in the water were assessed as activity counts. The behavioral alterations in the COCA-treated groups were compared with a group of mice given a 10 min immobilization stress (IM group). In the COCA-only group, a prolonged increase in the spontaneous behaviors accompanied by convulsive seizures was observed even in the surviving mice, unlike in the IM group. However, an acceleration of behavioral despair in the Porsolt test similar to that observed in the IM group was observed in the COCA group after the disappearance of the acute toxic symptoms (5 hours after the COCA treatment). Among the opioid-treated groups, the mortality rate was attenuated only in the COCA-BUP (0.25 mg/kg, i.p.) group. In the COCA-BUP group, a prolonged suppression of the morbid hyperactivity in the cage except for the convulsive seizures, and a normalization of the swimming behavior in the Porsolt test were observed in the survivors. On the other hand, in the COCA-PEN (5 mg/kg, i.p.) group, the swimming behavior in the Porsolt test was abnormally increased in addition to the prolonged morbid hyperactivity in the cage. Therefore, the COCA-induced stress-related behaviors were normalized in the group of mice treated with BUP, a group with a good prognosis.

Antidepressant-like effects of aniracetam in aged rats and its mode of action.

PubMed

Nakamura, K; Tanaka, Y

2001-11-01

Aniracetam has been reported to be efficacious for treating poststroke depression, but no studies that basically examined the antidepressive effects have been made. We aimed to test the antidepressant-like property of aniracetam in rats and to clarify the mechanisms of action through the interaction studies with some receptor antagonists. Antidepressant-like effects of aniracetam and various classes of compounds including different antidepressants were examined in a forced swim test with young (9 weeks old) and aged (25-30 months old) rats. Rats were exposed to a 5-min swim in a test session on day 2 following a 15-min swim in a training session on day 1, and immobility time during the period on day 2 was measured. The test compounds were administered subacutely (three doses over 2 days) or acutely (0.5 h before the testing). Standard antidepressants except for tandospirone significantly reduced immobility time in both young and aged rats. Aniracetam (10-100 mg/kg PO) failed to decrease immobility time in young rats, but it (100 mg/kg PO) significantly shortened immobility in aged rats, the effects of which were mainly mimicked by combined treatment of the metabolites, 2-pyrrolidinone and N-anisoyl-GABA. The effects of aniracetam was reversed completely by mecamylamine (10 mg/kg IP) or haloperidol (0.1 mg/kg IP) and slightly by ketanserin (1 m/kg IP) but was potentiated by scopolamine (0.03 mg/kg IP). These results indicate that aniracetam acts more effective when the forced swim stress-induced immobility is accompanied with brain dysfunction that occurs with aging. The antidepressant-like activity of aniracetam, which is probably due to the combined effects of 2-pyrrolidinone and N-anisoyl-GABA, may be mediated by mainly facilitating dopaminergic transmission (dopamine release and dopamine D2 receptor activation) through nicotinic acetylcholine receptor stimulation.

Mechanical models of sandfish locomotion reveal principles of high performance subsurface sand-swimming

PubMed Central

Maladen, Ryan D.; Ding, Yang; Umbanhowar, Paul B.; Kamor, Adam; Goldman, Daniel I.

2011-01-01

We integrate biological experiment, empirical theory, numerical simulation and a physical model to reveal principles of undulatory locomotion in granular media. High-speed X-ray imaging of the sandfish lizard, Scincus scincus, in 3 mm glass particles shows that it swims within the medium without using its limbs by propagating a single-period travelling sinusoidal wave down its body, resulting in a wave efficiency, η, the ratio of its average forward speed to the wave speed, of approximately 0.5. A resistive force theory (RFT) that balances granular thrust and drag forces along the body predicts η close to the observed value. We test this prediction against two other more detailed modelling approaches: a numerical model of the sandfish coupled to a discrete particle simulation of the granular medium, and an undulatory robot that swims within granular media. Using these models and analytical solutions of the RFT, we vary the ratio of undulation amplitude to wavelength (A/λ) and demonstrate an optimal condition for sand-swimming, which for a given A results from the competition between η and λ. The RFT, in agreement with the simulated and physical models, predicts that for a single-period sinusoidal wave, maximal speed occurs for A/λ ≈ 0.2, the same kinematics used by the sandfish. PMID:21378020

Impact of melatonin supplementation in the rat spermatogenesis subjected to forced swimming exercise.

PubMed

Moayeri, A; Mokhtari, T; Hedayatpour, A; Abbaszadeh, H-A; Mohammadpour, S; Ramezanikhah, H; Shokri, S

2018-04-01

Oxygen consumption increases many times during exercise, which can increase reactive oxygen species. It negatively affects fertility in male athletes. Melatonin is exerting a regulatory role at different levels of the hypothalamic-pituitary-gonadal axis. However, there is no evidence that the protective effects of melatonin persist after long duration exercise on the spermatogenesis. Therefore, this study was conducted to examine the impacts of melatonin on the testis following the administration of swimming exercise. Rats were separated into five different groups, including Control, sham M: received the solvent of melatonin, M: received melatonin, S: the exercise protocol, MS: received melatonin and the exercise protocol. After 8 weeks, animals were scarified and antioxidant enzymes levels of testes, spermatogenic cells apoptosis and sperm quality were measured. Swimming decreased all parameters of spermatozoa. Nevertheless, melatonin could significantly improve the progressive motility of spermatozoa in MS rats. Swimming caused an increased apoptosis of S group and decreased all antioxidant enzymes. Melatonin could drastically reduce apoptosis and increased these enzymes. Therefore, melatonin seems to induce the production of antioxidant enzymes of testicular tissues and diminish the extent of apoptotic changes caused by forced exercise on the testis, which can, in turn, ameliorate the sperm parameters. © 2017 Blackwell Verlag GmbH.

Effect of bacoside extract from Bacopa monniera on physical fatigue induced by forced swimming.

PubMed

Anand, T; Phani Kumar, G; Pandareesh, M D; Swamy, M S L; Khanum, Farhath; Bawa, A S

2012-04-01

The antifatigue effect of bacoside extract (BME) from Bacopa monniera (L.) Wettst. was investigated. Rats were subjected to weight-loaded forced swim test (WFST) every alternate day for 3 weeks. The BME at a dosage of 10 mg/kg body weight was administered orally to rats for 2 weeks in order to evaluate the following biomarkers of physical fatigue: swimming time, change in body weight, lipid peroxidation, lactic acid (LA), glycogen, antioxidant enzyme activities such as superoxide dismutase (SOD) and catalase (CAT) and blood parameters, namely blood urea nitrogen (BUN) and creatine kinase (CK). The exhaustive swimming time was increased by 3-fold in the BME supplemented group compared with that of the control group on day 13. The BME treatment lowered malondialdehyde (MDA) levels in brain, liver and muscle tissues by 11.2%, 16.2% and 37.7%, respectively, compared with the control exercised group (p < 0.05). The BME also reduced the LA, serum BUN and CK activities significantly compared with that of the control. Administration of BME significantly protected the depletion of SOD and CAT activities. The HSP-70 expression studies by western blot also confirmed the antifatigue property of BME. The present study thus indicates that BME ameliorates the various impairments associated with physical fatigue. Copyright © 2011 John Wiley & Sons, Ltd.

Control of movement initiation underlies the development of balance

PubMed Central

Ehrlich, David E.; Schoppik, David

2017-01-01

Summary Balance arises from the interplay of external forces acting on the body and internally generated movements. Many animal bodies are inherently unstable, necessitating corrective locomotion to maintain stability. Understanding how developing animals come to balance remains a challenge. Here we study the interplay between environment, sensation, and action as balance develops in larval zebrafish. We first model the physical forces that challenge underwater balance and experimentally confirm that larvae are subject to constant destabilization. Larvae propel in swim bouts that, we find, tend to stabilize the body. We confirm the relationship between locomotion and balance by changing larval body composition, exacerbating instability and eliciting more frequent swimming. Intriguingly, developing zebrafish come to control the initiation of locomotion, swimming preferentially when unstable, thus restoring preferred postures. To test the sufficiency of locomotor-driven stabilization and the developing control of movement timing, we incorporate both into a generative model of swimming. Simulated larvae recapitulate observed postures and movement timing across early development, but only when locomotor-driven stabilization and control of movement initiation are both utilized. We conclude the ability to move when unstable is the key developmental improvement to balance in larval zebrafish. Our work informs how emerging sensorimotor ability comes to impact how and why animals move when they do. PMID:28111151

Impact of water temperature and stressor controllability on swim stress-induced changes in body temperature, serum corticosterone, and immobility in rats.

PubMed

Drugan, Robert C; Eren, Senem; Hazi, Agnes; Silva, Jennifer; Christianson, John P; Kent, Stephen

2005-10-01

The present study compared the effects of three different water temperatures (20, 25, and 30 degrees C) and stressor controllability on several physiological and behavioral endpoints in an intermittent swim stress paradigm. The escape latency of rats in the 20 and 25 degrees C water was less than that observed for the 30 degrees C group. Both escape and yoked groups at 20 and 25 degrees C exhibited moderate to severe hypothermia following the swim stress session that returned to prestress levels 30-40 min post-stress. At 30 degrees C core body temperature (Tb) only decreased by 1 degree C for either swim group. Following swim, serum corticosterone (CORT) levels were significantly elevated in both escape and yoked groups in comparison to confined and home cage controls. The confined control group showed a significant elevation that was approximately halfway between the home cage control and the swim stress groups. At 30 degrees C, there was still a significant elevation of serum CORT in both swim groups in comparison to confined and home cage controls. Therefore, 30 degrees C appears to be the optimal water temperature to evaluate stress controllability effects in the current paradigm. In a final experiment, swim stressor controllability effects were examined in a 5 min forced swim test (FST) 24 h following the initial stress exposure. Rats exposed to yoked-inescapable swim stress at 30 degrees C exhibited more immobility than their escapable swim stress and confined counterparts, while the escape and confined controls did not differ. These results demonstrate that the behavioral deficits observed in the FST are attributable to the stress of inescapable swim and not swim stress per se.

A role for serotonin in the antidepressant activity of NG-Nitro-L-arginine, in the rat forced swimming test.

PubMed

Gigliucci, Valentina; Buckley, Kathleen Niamh; Nunan, John; O'Shea, Karen; Harkin, Andrew

2010-02-01

The present study determined regional serotonin (5-HT) synthesis and metabolism changes associated with the nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine (L-NA) and the influence of 5-HT receptor blockade in the antidepressant-like actions of L-NA in the forced swimming test (FST). Regional effects of L-NA (5,10 and 20mg/kg i.p.) on tryptophan hydroxylase (TPH) activity, the rate limiting enzyme for 5-HT synthesis, were determined by measuring accumulation of the transient intermediate 5-hydoxytryptophan (5-HTP) following in vivo administration of the amino acid decarboxylase inhibitor, NSD 1015 (100mg/kg). L-NA (5-20mg/kg) dose dependently increased 5-HTP accumulation, particularly in the amygdaloid cortex, following exposure to the FST. L-NA also provoked an increase in regional brain 5-HIAA concentrations and in the 5-HIAA:5-HT metabolism ratio. Co-treatment with NSD-1015 failed to consistently modify the antidepressant-like effects of L-NA in the FST. Sub-active doses of L-NA (1mg/kg) and the 5-HT re-uptake inhibitor fluoxetine (2.5mg/kg) acted synergistically to increase swimming in the test. Co-treatment with the non-selective 5-HT receptor antagonist metergoline (1, 2 and 4mg/kg), attenuated the L-NA (20mg/kg)-induced reduction in immobility and increase in swimming behaviours. Metergoline alone however provoked an increase in immobility and reduction in swimming behaviours in the test. A similar response was obtained following co-treatment with the preferential 5-HT(2A) receptor antagonist ketanserin (5mg/kg) and the 5-HT(2C) receptor antagonist RO-430440 (5mg/kg). Co-treatment with the 5-HT(1A) receptor antagonist WAY 100635 (0.3mg/kg) or the 5-HT(1B) receptor antagonist GR 127935 (4mg/kg) failed to influence the antidepressant-like activity of L-NA. Taken together these data provide further support for a role for 5-HT in the antidepressant-like properties of NOS inhibitors. Copyright 2009 Elsevier Inc. All rights reserved.

Antidepressant-like effects of the ethyl acetate soluble fraction of the root bark of Morus alba on the immobility behavior of rats in the forced swim test.

PubMed

Lim, Dong Wook; Kim, Yun Tai; Park, Ji-Hae; Baek, Nam-In; Han, Daeseok

2014-06-12

In this study, the antidepressant-like effects of Morus alba fractions in rats were investigated in the forced swim test (FST). Male Wistar rats (9-week-old) were administered orally the M. alba ethyl acetate (EtOAc 30 and 100 mg/kg) and M. alba n-butanol fractions (n-BuOH 30 and 100 mg/kg) every day for 7 consecutive days. On day 7, 1 h after the final administration of the fractions, the rats were exposed to the FST. M. alba EtOAc fraction at the dose of 100 mg/kg induced a decrease in immobility behavior (p < 0.01) with a concomitant increase in both climbing (p < 0.05) and swimming (p < 0.05) behaviors when compared with the control group, and M. alba EtOAc fraction at the dose of 100 mg/kg decreased the hypothalamic-pituitary-adrenal (HPA) axis response to the stress, as indicated by an attenuated corticosterone response and decreased c-fos immunoreactivity in the hippocampal and hypothalamic paraventricular nucleus (PVN) region. These findings demonstrated that M. alba EtOAc fraction have beneficial effects on depressive behaviors and restore both altered c-fos expression and HPA activity.

Antidepressant-like effects of the xanthine oxidase enzyme inhibitor allopurinol in rats. A comparison with fluoxetine.

PubMed

Gürbüz Özgür, Börte; Aksu, Hatice; Birincioğlu, Mustafa; Dost, Turhan

2015-11-01

Allopurinol is a xanthine oxidase enzyme inhibitor that is widely used for the treatment of hyperuricemia and gout. The activity of tryptophan 2,3-dioxygenase, which metabolizes tryptophan (TRP), is decreased by xanthine oxidase inhibitors, causing TRP levels in the body to be increased. Increases in TRP levels in the brain might have antidepressant effects. The purpose of this study is to evaluate the antidepressant effects of allopurinol compared to those of fluoxetine, which is a proven antidepressant. Thirty-two Wistar albino male rats were divided into four groups (control, 10mg/kg fluoxetine, 50mg/kg allopurinol, 50mg/kg allopurinol+10 mg/kg fluoxetine; n=8 per group), and forced swimming tests were performed before and after 14days of drug administration. Serotonin, 5-hydroxyindolacetic acid and uric acid levels were measured in blood samples after the final treatment. When allopurinol and fluoxetine were administered separately, a decrease in the duration of immobility and an increased duration of swimming were observed in the forced swimming test. The results showed similar antidepressant efficacies between allopurinol and fluoxetine. However, we found no statistically significant difference in the antidepressant effect of the combined therapy versus single drug therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

Controlled-frequency breath swimming improves swimming performance and running economy.

PubMed

Lavin, K M; Guenette, J A; Smoliga, J M; Zavorsky, G S

2015-02-01

Respiratory muscle fatigue can negatively impact athletic performance, but swimming has beneficial effects on the respiratory system and may reduce susceptibility to fatigue. Limiting breath frequency during swimming further stresses the respiratory system through hypercapnia and mechanical loading and may lead to appreciable improvements in respiratory muscle strength. This study assessed the effects of controlled-frequency breath (CFB) swimming on pulmonary function. Eighteen subjects (10 men), average (standard deviation) age 25 (6) years, body mass index 24.4 (3.7) kg/m(2), underwent baseline testing to assess pulmonary function, running economy, aerobic capacity, and swimming performance. Subjects were then randomized to either CFB or stroke-matched (SM) condition. Subjects completed 12 training sessions, in which CFB subjects took two breaths per length and SM subjects took seven. Post-training, maximum expiratory pressure improved by 11% (15) for all 18 subjects (P < 0.05) while maximum inspiratory pressure was unchanged. Running economy improved by 6 (9)% in CFB following training (P < 0.05). Forced vital capacity increased by 4% (4) in SM (P < 0.05) and was unchanged in CFB. These findings suggest that limiting breath frequency during swimming may improve muscular oxygen utilization during terrestrial exercise in novice swimmers. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Unsteady swimming of small organisms

NASA Astrophysics Data System (ADS)

Wang, Shiyan; Ardekani, Arezoo

2012-11-01

Small planktonic organisms ubiquitously display unsteady or impulsive motion to attack a prey or escape a predator in natural environments. Despite this, the role of unsteady hydrodynamic forces such as history and added mass forces on the low Reynolds number propulsion of small organisms is poorly understood. In this paper, we derive the fundamental equation of motion for an organism swimming by the means of surface distortion in a nonuniform flow at a low Reynolds number regime. We show that the history and added mass forces, that where traditionally neglected in the literature for small swimming organisms, cannot be neglected as the Stokes number increases above unity. For example, these unsteady inertial forces are of the same order as quasi-steady Stokes forces for Paramecium. Finally, we quantify the effects of convective inertial forces in the limit of small, but nonzero, Reynolds number regime. This work is supported by NSF grant CBET-1066545.

Involvement of central opioid systems in human interferon-α induced immobility in the mouse forced swimming test

PubMed Central

Makino, Mitsuhiro; Kitano, Yutaka; Komiyama, Chika; Hirohashi, Masaaki; Takasuna, Kiyoshi

2000-01-01

We investigated the mechanism by which human interferon-α (IFN-α) increases the immobility time in a forced swimming test, an animal model of depression.Central administration of IFN-α (0.05–50 IU per mouse, i.cist.) increased the immobility time in the forced swimming test in mice in a dose-dependent manner.Neither IFN-β nor -γ possessed any effect under the same experimental conditions.Pre-treatment with an opioid receptor antagonist, naloxone (1 mg kg−1, s.c.) inhibited the prolonged immobility time induced by IFN-α (60 KIU kg−1, i.v. or 50 IU per mouse. i.cist.).Peripheral administration of naloxone methiodide (1 mg kg−1, s.c.), which does not pass the blood–brain barrier, failed to block the effect of IFN-α, while intracisternal administration of naloxone methiodide (1 nmol per mouse) completely blocked.The effect of IFN-α was inhibited by a μ1-specific opioid receptor antagonist, naloxonazine (35 mg kg−1, s.c.) and a μ1/μ2 receptor antagonist, β-FNA (40 mg kg−1, s.c.). A selective δ-opioid receptor antagonist, naltrindole (3 mg kg−1, s.c.) and a κ-opioid receptor antagonist, nor-binaltorphimine (20 mg kg−1, s.c.), both failed to inhibit the increasing effect of IFN-α.These results suggest that the activator of the central opioid receptors of the μ1-subtype might be related to the prolonged immobility time of IFN-α, but δ and κ-opioid receptors most likely are not involved. PMID:10903965

Early Life Stress Increases Metabolic Risk, HPA Axis Reactivity, and Depressive-Like Behavior When Combined with Postweaning Social Isolation in Rats.

PubMed

Vargas, Javier; Junco, Mariana; Gomez, Carlos; Lajud, Naima

2016-01-01

Early-life stress is associated with depression and metabolic abnormalities that increase the risk of cardiovascular disease and diabetes. Such associations could be due to increased glucocorticoid levels. Periodic maternal separation in the neonate and rearing in social isolation are potent stressors that increase hypothalamus-pituitary-adrenal axis activity. Moreover, social isolation promotes feed intake and body weight gain in rats subjected to periodic maternal separation; however, its effects on metabolic risks have not been described. In the present study, we evaluated whether periodic maternal separation, social isolation rearing, and a combination of these two stressors (periodic maternal separation + social isolation rearing) impair glucose homeostasis and its relation to the hypothalamus-pituitary-adrenal axis and depressive-like behavior. Periodic maternal separation increased basal corticosterone levels, induced a passive coping strategy in the forced swimming test, and was associated with a mild (24%) increase in fasting glucose, insulin resistance, and dyslipidemia. Rearing in social isolation increased stress reactivity in comparison to both controls and in combination with periodic maternal separation, without affecting the coping strategy associated with the forced swimming test. However, social isolation also increased body weight gain, fasting glucose (120%), and insulin levels in rats subjected to periodic maternal separation. Correlation analyses showed that stress-induced effects on coping strategy on the forced swimming test (but not on metabolic risk markers) are associated with basal corticosterone levels. These findings suggest that maternal separation and postweaning social isolation affect stress and metabolic vulnerability differentially and that early-life stress-related effects on metabolism are not directly dependent on glucocorticoid levels. In conclusion, our study supports the cumulative stress hypothesis, which suggests that metabolic risk markers arise when vulnerable individuals are exposed to social challenges later in life.

Effect of co-administration of fluoxetine and amantadine on immunoendocrine parameters in rats subjected to a forced swimming test.

PubMed

Rogóz, Zofia; Kubera, Marta; Rogóz, Katarzyna; Basta-Kaim, Agnieszka; Budziszewska, Bogusława

2009-01-01

Considerable attention has been paid to a possible role of immunological dysregulation in the pathogenesis of depression. It has been reported that combined administration of antidepressant drugs and the non-competitive NMDA receptor antagonist amantadine reduces immobility time in the forced swimming test (FST). Moreover, preliminary clinical data show that such a combination of drugs has a beneficial effect on treatment-resistant depressed patients. Since immune activation and a pro-inflammatory response are clearly evident in treatment-resistant depression, the aim of the present study was to examine the effect of a combination of the antidepressant fluoxetine and amantadine on immunoendocrine parameters in rats subjected to the forced swimming test. The obtained results revealed synergistic antidepressant effects of the combined administration of fluoxetine (10 mg/kg) and amantadine (10 mg/kg) - drugs otherwise ineffective when given separately in the above doses. Antidepressant activity was accompanied with a significant decrease in the capacity of splenocytes to proliferate in response to concanavalin A. Moerover, fluoxetine and the combination of amantadine and fluoxetine reduced relative spleen weight in rats subjected to the FST, compared to rats treated with the vehicle. The combination of amantadine and fluoxetine enhanced the production of the negative immunoregulator interleukin-10 (but not interferon-gamma) in rats subjected to the FST. The exposure to the FST produced an increase in plasma corticosterone levels, which was significantly attenuated by pretreatment with fluoxetine and amantadine. In summary, the antidepressive efficacy of a combination of fluoxetine and amantadine given in suboptimal doses may be related to the negative immunoendocrine effects of these drugs.

Effects of early life abuse differ across development: Infant social behavior deficits are followed by adolescent depressive-like behaviors mediated by the amygdala

PubMed Central

Raineki, Charlis; Cortés, Millie Rincón; Belnoue, Laure; Sullivan, Regina M.

2012-01-01

Abuse during early life, especially from the caregiver, increases vulnerability to develop later life psychopathologies such as depression. Although signs of depression are typically not expressed until later life, signs of dysfunctional social behavior have been found earlier. How infant abuse alters the trajectory of brain development to produce pathways to pathology is not completely understood. Here we address this question using two different but complementary rat models of early-life abuse from postnatal days (PN) 8–12: a naturalistic paradigm, where the mother is provided with insufficient bedding for nest building and a more controlled paradigm, where infants undergo olfactory classical conditioning. Amygdala neural assessment (c-Fos), as well as social behavior and forced swim tests were performed at preweaning (PN20) and adolescence (PN45). Our results show that both models of early life abuse induce deficits in social behavior, even during the preweaning period; however, depressive-like behaviors were observed only during adolescence. Adolescent depressive-like behavior corresponds with an increase in amygdala neural activity in response to forced swim test. A causal relationship between the amygdala and depressive-like behavior was suggested through amygdala temporary deactivation (muscimol infusions), which rescued the depressive-like behavior in the forced swim test. Our results indicate that social behavior deficits in infancy could serve as an early marker for later psychopathology. Moreover, the implication of the amygdala in the ontogeny of depressive-like behaviors in infant abused animals is an important step toward understanding the underlying mechanisms of later life mental disease associated with early-life abuse. PMID:22649253

Effects of a glycine transporter-1 inhibitor and D-serine on MK-801-induced immobility in the forced swimming test in rats.

PubMed

Kawaura, Kazuaki; Koike, Hiroyuki; Kinoshita, Kohnosuke; Kambe, Daiji; Kaku, Ayaka; Karasawa, Jun-ichi; Chaki, Shigeyuki; Hikichi, Hirohiko

2015-02-01

Glutamatergic dysfunction, particularly the hypofunction of N-methyl-D-aspartate (NMDA) receptors, is involved in the pathophysiology of schizophrenia. The positive modulation of the glycine site on the NMDA receptor has been proposed as a novel therapeutic approach for schizophrenia. However, its efficacy against negative symptoms, which are poorly managed by current medications, has not been fully addressed. In the present study, the effects of the positive modulation of the glycine site on the NMDA receptor were investigated in an animal model of negative symptoms of schizophrenia. The subchronic administration of MK-801 increased immobility in the forced swimming test in rats without affecting spontaneous locomotor activity. The increased immobility induced by MK-801 was attenuated by the atypical antipsychotic clozapine but not by either the typical antipsychotic haloperidol or the antidepressant imipramine, indicating that the increased immobility induced by subchronic treatment with MK-801 in the forced swimming test may represent a negative symptom of schizophrenia. Likewise, positive modulation of the glycine sites on the NMDA receptor using an agonist for the glycine site, D-serine, and a glycine transporter-1 inhibitor, N-[(3R)-3-([1,1'-biphenyl]-4-yloxy)-3-(4-fluorophenyl)propyl]-N-methylglycine hydrochloride (NFPS), significantly reversed the increase in immobility in MK-801-treated rats without reducing the immobility time in vehicle-treated rats. The present results show that the stimulation of the NMDA receptor through the glycine site on the receptor either directly with D-serine or by blocking glycine transporter-1 attenuates the immobility elicited by the subchronic administration of MK-801 and may be potentially useful for the treatment of negative symptoms of schizophrenia. Copyright © 2014 Elsevier B.V. All rights reserved.

The melanocortinergic pathway is rapidly recruited by emotional stress and contributes to stress-induced anorexia and anxiety-like behavior.

PubMed

Liu, Jing; Garza, Jacob C; Truong, Ha V; Henschel, John; Zhang, Wei; Lu, Xin-Yun

2007-11-01

Neurons producing melanocortin receptor agonist, alpha-MSH derived from proopiomelanocortin, and antagonist, agouti-related protein, are known to be sensitive to metabolic stress such as food deprivation and glucoprivation. However, how these neurons respond to emotional/psychological stress remained to be elucidated. We report here that acute emotional stressors, i.e. restraint and forced swim, evoked mRNA expression of c-fos, a neuronal activation marker, in a high percentage of proopiomelanocortin neurons (up to 53% for restraint stress and 62% for forced swim), with marked variations along the rostro-caudal axis of the arcuate nucleus. In contrast, only a small population of agouti-related protein neurons in this brain region was activated. These neuronal activation patterns were correlated with behavioral reactions. Both stressors suppressed feeding and induced anxiety-like behavior in the elevated plus-maze test, as reflected by a reduction in the percentage of entries and time spent in the open arms. Central pretreatment with SHU9119, a melanocortin receptor antagonist, dose dependently attenuated the anorectic and anxiogenic effects elicited by acute restraint or forced swim. These results indicate that the melancortinergic pathway can be rapidly recruited by acute emotional stress, and that activation of melanocortin signaling is involved in mediating stress-induced anorexia and anxiety.

The neuroendocrine response to stress under the effect of drugs: Negative synergy between amphetamine and stressors.

PubMed

Gómez-Román, Almudena; Ortega-Sánchez, Juan A; Rotllant, David; Gagliano, Humberto; Belda, Xavier; Delgado-Morales, Raúl; Marín-Blasco, Ignacio; Nadal, Roser; Armario, Antonio

2016-01-01

There have been numerous studies into the interaction between stress and addictive drugs, yet few have specifically addressed how the organism responds to stress when under the influence of psychostimulants. Thus, we studied the effects of different acute stressors (immobilization, interleukin-1β and forced swimming) in young adult male rats simultaneously exposed to amphetamine (AMPH, 4 mg/kg SC), evaluating classic biological markers. AMPH administration itself augmented the plasma hypothalamic-pituitary-adrenal (HPA) hormones, adrenocorticotropin (ACTH) and corticosterone, without affecting plasma glucose levels. By contrast, this drug dampened the peripheral HPA axis, as well as the response of glucose to the three stressors. We also found that AMPH administration completely blocked the forced swim-induced expression of the corticotropin-releasing hormone (hnCRH) and it partially reduced c-fos expression in the paraventricular nucleus of the hypothalamus (PVN). Indeed, this negative synergy in the forced swim test could even be observed with a lower dose of AMPH (1mg/kg, SC), a dose that is usually received in self-administration experiments. In conclusion, when rats that receive AMPH are subjected to stress, a negative synergy occurs that dampens the prototypic peripheral physiological response to stress and activation of the PVN. Copyright © 2015 Elsevier Ltd. All rights reserved.

Physical Forces Shape Group Identity of Swimming Pseudomonas putida Cells.

PubMed

Espeso, David R; Martínez-García, Esteban; de Lorenzo, Víctor; Goñi-Moreno, Ángel

2016-01-01

The often striking macroscopic patterns developed by motile bacterial populations on agar plates are a consequence of the environmental conditions where the cells grow and spread. Parameters such as medium stiffness and nutrient concentration have been reported to alter cell swimming behavior, while mutual interactions among populations shape collective patterns. One commonly observed occurrence is the mutual inhibition of clonal bacteria when moving toward each other, which results in a distinct halt at a finite distance on the agar matrix before having direct contact. The dynamics behind this phenomenon (i.e., intolerance to mix in time and space with otherwise identical others) has been traditionally explained in terms of cell-to-cell competition/cooperation regarding nutrient availability. In this work, the same scenario has been revisited from an alternative perspective: the effect of the physical mechanics that frame the process, in particular the consequences of collisions between moving bacteria and the semi-solid matrix of the swimming medium. To this end, we set up a simple experimental system in which the swimming patterns of Pseudomonas putida were tested with different geometries and agar concentrations. A computational analysis framework that highlights cell-to-medium interactions was developed to fit experimental observations. Simulated outputs suggested that the medium is compressed in the direction of the bacterial front motion. This phenomenon generates what was termed a compression wave that goes through the medium preceding the swimming population and that determines the visible high-level pattern. Taken together, the data suggested that the mechanical effects of the bacteria moving through the medium created a factual barrier that impedes to merge with neighboring cells swimming from a different site. The resulting divide between otherwise clonal bacteria is thus brought about by physical forces-not genetic or metabolic programs.

Effects of fluoxetine on the rat brain in the forced swimming test: a [F-18]FDG micro-PET imaging study.

PubMed

Jang, Dong-Pyo; Lee, So-Hee; Park, Chan-Woong; Lee, Sang-Yoon; Kim, Young-Bo; Cho, Zang-Hee

2009-02-13

We used the [F-18]FDG micro-PET neuroimaging to examine the effects of fluoxetine on brain activity in rats and on their behavioral response in the forced swimming test (FST). In the first experiment, the rats were administered doses of fluoxetine (10 or 20mg/kg) 24, 19 and 1h before the rat brains were scanned. Fluoxetine induced strong activation of the dorsal hippocampus and the deactivation of the inferior colliculus, medulla oblongata, and prelimbic cortex in a dose-dependent manner. These results seemed to be related with the changes in 5-HT (5-hydroxytryptamine, serotonin) levels after selective serotonin reuptake-inhibitor treatments. In the second experiment, the changes in glucose metabolism in the test session were measured after fluoxetine was given between pre-test and test sessions of the FST. Fluoxetine administration significantly decreased immobility behavior compared with saline administration. At the same time, the activity of the insular/piriform cortex decreased significantly. In contrast, the extent of cerebellar activation increased. The glucose metabolism of the dorsal hippocampus also increased, which suggests that post-stress changes in the facilitation of hippocampal serotonergic neurotransmission lead to decreased immobilization in the FST.

Effect of potassium channel modulators in mouse forced swimming test

PubMed Central

Galeotti, Nicoletta; Ghelardini, Carla; Caldari, Bernardetta; Bartolini, Alessandro

1999-01-01

The effect of intracerebroventricular (i.c.v.) administration of different potassium channel blockers (tetraethylammonium, apamin, charybdotoxin, gliquidone), potassium channel openers (pinacidil, minoxidil, cromakalim) and aODN to mKv1.1 on immobility time was evaluated in the mouse forced swimming test, an animal model of depression. Tetraethylammonium (TEA; 5 μg per mouse i.c.v.), apamin (3 ng per mouse i.c.v.), charybdotoxin (1 μg per mouse i.c.v.) and gliquidone (6 μg per mouse i.c.v.) administered 20 min before the test produced anti-immobility comparable to that induced by the tricyclic antidepressants amitriptyline (15 mg kg−1 s.c.) and imipramine (30 mg kg−1 s.c.). By contrast pinacidil (10–20 μg per mouse i.c.v.), minoxidil (10–20 μg per mouse i.c.v.) and cromakalim (20–30 μg per mouse i.c.v.) increased immobility time when administered in the same experimental conditions. Repeated administration of an antisense oligonucleotide (aODN) to the mKv1.1 gene (1 and 3 nmol per single i.c.v. injection) produced a dose-dependent increase in immobility time of mice 72 h after the last injection. At day 7, the increasing effect produced by aODN disappeared. A degenerate mKv1.1 oligonucleotide (dODN), used as control, did not produce any effect in comparison with saline- and vector-treated mice. At the highest effective dose, potassium channels modulators and the mKv1.1 aODN did not impair motor coordination, as revealed by the rota rod test, nor did they modify spontaneous motility as revealed by the Animex apparatus. These results suggest that modulation of potassium channels plays an important role in the regulation of immobility time in the mouse forced swimming test. PMID:10323599

Sink or Swim: Navigating the Perilous Waters of Promotion and Tenure--What's Diversity Got to Do with It?

ERIC Educational Resources Information Center

Knight, Wanda B.

2010-01-01

The "sink-or-swim" ideology is pervasive in the United States society. At research universities, for example, promotion and tenure are institutional waters in which faculty are forced to sink or swim with respect to publishing. Either they publish ("swim") or they perish ("sink"). In throwing faculty overboard,…

Mechanisms underlying rhythmic locomotion: body–fluid interaction in undulatory swimming

PubMed Central

Chen, J.; Friesen, W. O.; Iwasaki, T.

2011-01-01

Swimming of fish and other animals results from interactions of rhythmic body movements with the surrounding fluid. This paper develops a model for the body–fluid interaction in undulatory swimming of leeches, where the body is represented by a chain of rigid links and the hydrodynamic force model is based on resistive and reactive force theories. The drag and added-mass coefficients for the fluid force model were determined from experimental data of kinematic variables during intact swimming, measured through video recording and image processing. Parameter optimizations to minimize errors in simulated model behaviors revealed that the resistive force is dominant, and a simple static function of relative velocity captures the essence of hydrodynamic forces acting on the body. The model thus developed, together with the experimental kinematic data, allows us to investigate temporal and spatial (along the body) distributions of muscle actuation, body curvature, hydrodynamic thrust and drag, muscle power supply and energy dissipation into the fluid. We have found that: (1) thrust is generated continuously along the body with increasing magnitude toward the tail, (2) drag is nearly constant along the body, (3) muscle actuation waves travel two or three times faster than the body curvature waves and (4) energy for swimming is supplied primarily by the mid-body muscles, transmitted through the body in the form of elastic energy, and dissipated into the water near the tail. PMID:21270304

Swimming in a granular frictional fluid

NASA Astrophysics Data System (ADS)

Goldman, Daniel

2012-02-01

X-ray imaging reveals that the sandfish lizard swims within granular media (sand) using axial body undulations to propel itself without the use of limbs. To model the locomotion of the sandfish, we previously developed an empirical resistive force theory (RFT), a numerical sandfish model coupled to an experimentally validated Discrete Element Method (DEM) model of the granular medium, and a physical robot model. The models reveal that only grains close to the swimmer are fluidized, and that the thrust and drag forces are dominated by frictional interactions among grains and the intruder. In this talk I will use these models to discuss principles of swimming within these granular ``frictional fluids". The empirical drag force laws are measured as the steady-state forces on a small cylinder oriented at different angles relative to the displacement direction. Unlike in Newtonian fluids, resistive forces are independent of speed. Drag forces resemble those in viscous fluids while the ratio of thrust to drag forces is always larger in the granular media than in viscous fluids. Using the force laws as inputs, the RFT overestimates swimming speed by approximately 20%. The simulation reveals that this is related to the non-instantaneous increase in force during reversals of body segments. Despite the inaccuracy of the steady-state assumption, we use the force laws and a recently developed geometric mechanics theory to predict optimal gaits for a model system that has been well-studied in Newtonian fluids, the three-link swimmer. The combination of the geometric theory and the force laws allows us to generate a kinematic relationship between the swimmer's shape and position velocities and to construct connection vector field and constraint curvature function visualizations of the system dynamics. From these we predict optimal gaits for forward, lateral and rotational motion. Experiment and simulation are in accord with the theoretical prediction, and demonstrate that swimming in sand can be viewed as movement in a localized frictional fluid.

Evaluation of the role of NMDA receptor function in antidepressant-like activity. A new study with citalopram and fluoxetine in the forced swim test in mice.

PubMed

Wolak, Małgorzata; Siwek, Agata; Szewczyk, Bernadeta; Poleszak, Ewa; Bystrowska, Beata; Moniczewski, Andrzej; Rutkowska, Anita; Młyniec, Katarzyna; Nowak, Gabriel

2015-06-01

The NMDA/glutamate receptors are involved in the mechanism of antidepressant activity. The present study was designed to investigate the effect of NMDA receptor ligands (agonists and antagonists of glutamate sites) on the antidepressant-like activity of selective serotonin reuptake inhibitors (SSRIs), citalopram and fluoxetine, in the forced swim test in mice. The antidepressant activity (reduction in immobility time) of citalopram but not of fluoxetine was antagonized by N-methyl-D-aspartate acid and enhanced by CGP37849 (antagonist of the NMDA receptor). The present literature data indicate that the antidepressant-like activity of conventional antidepressants is generally affected by the NMDA receptor, although by modulation from different sites of the complex. Thus, it supports the issue of the ability of NMDA receptor antagonists to enhance the antidepressant action in human depression. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Mice with ablated adult brain neurogenesis are not impaired in antidepressant response to chronic fluoxetine.

PubMed

Jedynak, Paulina; Kos, Tomasz; Sandi, Carmen; Kaczmarek, Leszek; Filipkowski, Robert K

2014-09-01

The neurogenesis hypothesis of major depression has two main facets. One states that the illness results from decreased neurogenesis while the other claims that the very functioning of antidepressants depends on increased neurogenesis. In order to verify the latter, we have used cyclin D2 knockout mice (cD2 KO mice), known to have virtually no adult brain neurogenesis, and we demonstrate that these mice successfully respond to chronic fluoxetine. After unpredictable chronic mild stress, mutant mice showed depression-like behavior in forced swim test, which was eliminated with chronic fluoxetine treatment, despite its lack of impact on adult hippocampal neurogenesis in cD2 KO mice. Our results suggest that new neurons are not indispensable for the action of antidepressants such as fluoxetine. Using forced swim test and tail suspension test, we also did not observe depression-like behavior in control cD2 KO mice, which argues against the link between decreased adult brain neurogenesis and major depression. Copyright © 2014 Elsevier Ltd. All rights reserved.

The antidepressant-like effect of trans-astaxanthin involves the serotonergic system.

PubMed

Jiang, Xi; Zhu, Keqi; Xu, Quanyi; Wang, Guokang; Zhang, Jiajia; Cao, Rongrong; Ye, Jiang; Yu, Xuefeng

2017-04-11

The antidepressant-like effect of trans-astaxanthin, a compound present rich in algae, was evaluated through behavioral and neurochemical methods. Results showed that trans-astaxanthin treatment significantly decreased the immobility time in force swim test and tail suspension test, but did not influence locomotor activity. Trans-astaxanthin treatment did not effectively antagonize hypothermia and ptosis induced by reserpine. However, pre-treatment with para-chlorophenylalanine abolished the anti-immobility effect of trans-astaxanthin in force swim and tail suspension test. These results suggested that the mechanism of antidepressant-like effect of trans-astaxanthin may involve the serotonergic system, but not noradrenaline system. This hypothesis was confirmed by neurochemical assays which showed that trans-astaxanthin increased serotonin levels in the hippocampus, frontal cortex, striatum and hypothalamus. Furthermore, our data suggested that trans-astaxanthin decreased indoleamine 2, 3-dioxygenase activity in the hippocampus, frontal cortex and hypothalamus. Inhibition of indoleamine 2,3-dioxygenase activity subsequently decreased the kynurenine/tryptophan ratio and increased the serotonin/tryptophan ratio in these brain regions. Taken together, these findings indicate that the antidepressant-like effect of trans-astaxanthin involves the serotonergic system.

The antidepressant-like effect of trans-astaxanthin involves the serotonergic system

PubMed Central

Jiang, Xi; Zhu, Keqi; Xu, Quanyi; Wang, Guokang; Zhang, Jiajia; Cao, Rongrong; Ye, Jiang; Yu, Xuefeng

2017-01-01

The antidepressant-like effect of trans-astaxanthin, a compound present rich in algae, was evaluated through behavioral and neurochemical methods. Results showed that trans-astaxanthin treatment significantly decreased the immobility time in force swim test and tail suspension test, but did not influence locomotor activity. Trans-astaxanthin treatment did not effectively antagonize hypothermia and ptosis induced by reserpine. However, pre-treatment with para-chlorophenylalanine abolished the anti-immobility effect of trans-astaxanthin in force swim and tail suspension test. These results suggested that the mechanism of antidepressant-like effect of trans-astaxanthin may involve the serotonergic system, but not noradrenaline system. This hypothesis was confirmed by neurochemical assays which showed that trans-astaxanthin increased serotonin levels in the hippocampus, frontal cortex, striatum and hypothalamus. Furthermore, our data suggested that trans-astaxanthin decreased indoleamine 2, 3-dioxygenase activity in the hippocampus, frontal cortex and hypothalamus. Inhibition of indoleamine 2,3-dioxygenase activity subsequently decreased the kynurenine/tryptophan ratio and increased the serotonin/tryptophan ratio in these brain regions. Taken together, these findings indicate that the antidepressant-like effect of trans-astaxanthin involves the serotonergic system. PMID:28424423

Increased anxiety and "depressive" symptoms months after MDMA ("ecstasy") in rats: drug-induced hyperthermia does not predict long-term outcomes.

PubMed

McGregor, Iain S; Gurtman, Clint G; Morley, Kirsten C; Clemens, Kelly J; Blokland, Arjan; Li, Kong M; Cornish, Jennifer L; Hunt, Glenn E

2003-08-01

There is some uncertainty whether the acute hyperthermia caused by MDMA (ecstasy) plays a significant role in determining the long-term neurotoxic effects on brain 5-HT systems and associated changes in mood and behaviour. The present study assessed whether long-term behavioural and cognitive changes seen in MDMA-treated rats are affected by hyperthermia at the time of drug administration. Male Wistar rats were treated with MDMA (4x5 mg/kg i.p. over 4 h on 2 consecutive days) or vehicle at either a high ambient temperature (28 degrees C) or a low ambient temperature (16 degrees C). Eight to 18 weeks later, rats were tested in behavioural measures of anxiety (social interaction and emergence tests), a test of cognition (object recognition test) and the forced swim test of depression. At the conclusion of behavioural testing the rats were killed and their brains analysed using HPLC. MDMA treatment caused a clear and consistent hyperthermia at 28 degrees C and hypothermia at 16 degrees C. Months later, rats pre-treated with MDMA at either 16 or 28 degrees C displayed increased anxiety in the social interaction and emergence tests and reduced escape attempts and increased immobility in the forced swim test. MDMA pre-treatment was also associated with poorer memory on the object recognition test, but only in rats given the drug at 28 degrees C. Rats pre-treated with MDMA showed loss of 5-HT in the hippocampus, striatum, amygdala and cortex, regardless of body temperature at the time of dosing. However, 5-HIAA loss in the amygdala and hippocampus was greater in rats pre-treated at 28 degrees C. Dopamine in the striatum was also depleted in rats given MDMA. These results indicate that hyperthermia at the time of dosing with MDMA is not necessary to produce subsequent 5-HT depletion and anxiety in rats. They also extend previous findings of long-term effects of brief exposure to MDMA in rats to include apparent "depressive" symptoms in the forced swim model.

Effect of co-treatment with fluoxetine or mirtazapine and risperidone on the active behaviors and plasma corticosterone concentration in rats subjected to the forced swim test.

PubMed

Rogóż, Zofia; Kabziński, Marcin; Sadaj, Witold; Rachwalska, Paulina; Gądek-Michalska, Anna

2012-01-01

Several clinical reports have postulated a beneficial effect of the addition of a low dose of risperidone to the ongoing treatment with antidepressants in treatment-resistant depression. The present study aimed to examine the effect of treatment with fluoxetine or mirtazapine, given separately or jointly with risperidone, on active behavior and plasma corticosterone level in male Wistar rats subjected to the forced swim test (FST). The obtained results showed that fluoxetine (5 mg/kg), mirtazapine (5 and 10 mg/kg) or risperidone (0.05 and 0.1 mg/kg) did not change the active behavior of rats in the FST. However, co-treatment with fluoxetine (10 mg/kg) and risperidone (0.1 mg/kg) induced an antidepressant-like effect in that test because it significantly increased the swimming time and decreased the immobility time, while combined treatment with mirtazapine at 5 and 10 mg/kg and risperidone at 0.05 and 0.1 mg/kg evoked a significant increase in the swimming time and also climbing, and decreased the immobility time. WAY 100635 (a 5-HT(1A) receptor antagonist) at a dose of 0.1 mg/kg inhibited the antidepressant-like effect induced by co-administration of fluoxetine or mirtazapine and risperidone. Active behavior in that test did not reflect an increase in general activity, since combined treatment with fluoxetine or mirtazapine and risperidone failed to enhance the exploratory activity of rats. Co-treatment with fluoxetine or mirtazapine and risperidone did not reduce the stress-induced increase in plasma corticosterone concentration in animals subjected to the FST. The obtained results indicate that risperidone applied in a low dose enhances the antidepressant-like activity of fluoxetine and mirtazapine in the FST (but does not normalize the stress-induced increase in corticosterone level in these rats), and that 5-HT(1A) receptors may play some role in these effects.

Adolescence fluoxetine increases serotonergic activity in the raphe-hippocampus axis and improves depression-like behaviors in female rats that experienced neonatal maternal separation.

PubMed

Yoo, Sang Bae; Kim, Bom-Taeck; Kim, Jin Young; Ryu, Vitaly; Kang, Dong-Won; Lee, Jong-Ho; Jahng, Jeong Won

2013-06-01

This study was conducted to examine if fluoxetine, a selective 5-hydroxytryptamine (5-HT) reuptake inhibitor, would reverse adverse behavioral effects of neonatal maternal separation in female rats. Sprague-Dawley pups were separated from dam daily for 3h during postnatal day (PND) 1-14 (maternal separation; MS) or left undisturbed (non-handled; NH). Female NH and MS pups received intraperitoneal injection of fluoxetine (10mg/kg) or vehicle daily from PND 35 until the end of the whole experimental period. Rats were either subjected to behavioral tests during PND 44-54, or sacrificed for neurochemical analyses during PND 43-45. Daily food intake and weight gain of both NH and MS pups were suppressed by fluoxetine, with greater effects in MS pups. MS experience increased immobility and decrease swimming in forced swim test. Swimming was increased, although immobility was not significantly decreased, in MS females by adolescence fluoxetine. However, adolescence fluoxetine increased immobility during forced swim test and decreased time spent in open arms during elevated plus maze test in NH females. Fluoxetine normalized MS-induced decrease of the raphe 5-HT levels and increased 5-HT metabolism in the hippocampus in MS females, and increased the hypothalamic 5-HT both in NH and MS. Fluoxetine decreased the raphe 5-HT and increased the plasma corticosterone in NH females. Results suggest that decreased 5-HTergic activity in the raphe nucleus is implicated in the pathophysiology of depression-like behaviors, and increased 5-HTergic activities in the raphe-hippocampus axis may be a part of anti-depressant efficacy of fluoxetine, in MS females. Also, an extra-hypothalamic 5-HTergic activity may contribute to the increased anorectic efficacy of fluoxetine in MS females. Additionally, decreased 5-HT in the raphe and elevated plasma corticosterone may be related with fluoxetine-induced depression- and/or anxiety-like behaviors in NH females. Copyright © 2012 Elsevier Ltd. All rights reserved.

Hydrodynamic stability of the painted turtle (Chrysemys picta): effects of four-limbed rowing versus forelimb flapping in rigid-bodied tetrapods

PubMed Central

Rivera, Gabriel; Rivera, Angela R. V.; Blob, Richard W.

2011-01-01

Hydrodynamic stability is the ability to resist recoil motions of the body produced by destabilizing forces. Previous studies have suggested that recoil motions can decrease locomotor performance, efficiency and sensory perception and that swimming animals might utilize kinematic strategies or possess morphological adaptations that reduce recoil motions and produce more stable trajectories. We used high-speed video to assess hydrodynamic stability during rectilinear swimming in the freshwater painted turtle (Chrysemys picta). Parameters of vertical stability (heave and pitch) were non-cyclic and variable, whereas measures of lateral stability (sideslip and yaw) showed repeatable cyclic patterns. In addition, because freshwater and marine turtles use different swimming styles, we tested the effects of propulsive mode on hydrodynamic stability during rectilinear swimming, by comparing our data from painted turtles with previously collected data from two species of marine turtle (Caretta caretta and Chelonia mydas). Painted turtles had higher levels of stability than both species of marine turtle for six of the eight parameters tested, highlighting potential disadvantages associated with ‘aquatic flight’. Finally, available data on hydrodynamic stability of other rigid-bodied vertebrates indicate that turtles are less stable than boxfish and pufferfish. PMID:21389201

Hip Strength Improves Novice Surface Combat Swimming Flutterkick Performance.

PubMed

Beethe, Anne Z; Nagle, Elizabeth F; Lovalekar, Mita; Nagai, Takashi; Nindl, Bradley C; Connaboy, Christopher

2018-05-29

The current study was designed to examine strength, range of motion (ROM), anthropometric, and physiological contributions to novice surface combat swimming (sCS) performance, and establish differences from freestyle swimming (FS) performance to further understand the transition of FS to sCS performance. Thirteen competitive swimmers (7 males, 6 females; 27.7±2.3 years; 176.2±2.6 cm; 75.4±3.9 kg) completed eight testing sessions consisting of the following: physiological land-based measurements for maximal anaerobic and aerobic capacity and upper and lower extremity strength and ROM, a sCS anaerobic capacity swim test measuring peak and mean force and fatigue index, two aerobic capacity tests measuring maximal aerobic capacity for both FS and sCS, and four 500m performance swims for time, one FS and three sCS. Separate multiple linear regression analysis was used to analyze predictors of both sCS and FS performance models. Freestyle swimming performance was predicted by the final FS VO 2max with a R 2 of 42.03% (F(1,10) = 7.25; p = 0.0226) whereas sCS performance was predicted by isometric hip extension peak strength with an R 2 of 41.46% (F(1,11) = 7.79; p = 0.0176). Results demonstrate different physiological characteristics predict performance, suggesting an altered strategy is utilized for novice sCS than FS. It is suggested this may be due to the added constraints as mandated by mission requirements including boots, weighted gear, and clandestine requirements with hips lowered beneath the surface. Further research should examine the kinematics of the sCS flutterkick to improve performance by developing training strategies specific for the task.

An analytical model of flagellate hydrodynamics

NASA Astrophysics Data System (ADS)

Dölger, Julia; Bohr, Tomas; Andersen, Anders

2017-04-01

Flagellates are unicellular microswimmers that propel themselves using one or several beating flagella. We consider a hydrodynamic model of flagellates and explore the effect of flagellar arrangement and beat pattern on swimming kinematics and near-cell flow. The model is based on the analytical solution by Oseen for the low Reynolds number flow due to a point force outside a no-slip sphere. The no-slip sphere represents the cell and the point force a single flagellum. By superposition we are able to model a freely swimming flagellate with several flagella. For biflagellates with left-right symmetric flagellar arrangements we determine the swimming velocity, and we show that transversal forces due to the periodic movements of the flagella can promote swimming. For a model flagellate with both a longitudinal and a transversal flagellum we determine radius and pitch of the helical swimming trajectory. We find that the longitudinal flagellum is responsible for the average translational motion whereas the transversal flagellum governs the rotational motion. Finally, we show that the transversal flagellum can lead to strong feeding currents to localized capture sites on the cell surface.

Neurotrophic peptide ACTH-(4-10) permits glucocorticoid-facilitated retention of acquired immobility response of hypophysectomized rats.

PubMed

De Kock, S; De Kloet, E R

1987-09-23

The Porsolt swimming test, which was originally designed as an experimental model to screen potential antidepressants demands that rats be forced to swim for 15 min in a narrow cylinder. Twenty four hours later they are retested for 5 min during which they stay immobile for approximately 70% of the time. The present study showed that hypophysectomized animals, 14 days after operation, were unable to retain the acquired immobility. Subcutaneous glucocorticoid administration did not restore the retention of acquired immobility in contrast to our earlier finding with adrenalectomized animals. The deficit in responsiveness to glucocorticoids was eliminated when the hypophysectomized rats received ACTH-(4-10)s.c. (20 micrograms/rat) every other day. Chronic treatment with only the peptide did not improve the impaired retention of hypophysectomized rats and a single ACTH-(4-10) injection 1 day or 1 h prior to initial testing was also ineffective. We conclude that the neurotrophic peptide ACTH-(4-10) permits the expression of the glucocorticoid effect on retention of acquired immobility in the swimming test.

Akt2 deficiency is associated with anxiety and depressive behavior in mice.

PubMed

Leibrock, Christina; Ackermann, Teresa F; Hierlmeier, Michael; Lang, Florian; Borgwardt, Stefan; Lang, Undine E

2013-01-01

The economic burden associated with major depressive disorder and anxiety disorders render both disorders the most common and debilitating psychiatric illnesses. To date, the exact cellular and molecular mechanisms underlying the pathophysiology, successful treatment and prevention of these highly associated disorders have not been identified. Akt2 is a key protein in the phosphatidylinositide-3 (PI3K) / glycogen synthase 3 kinase (GSK3) signaling pathway, which in turn is involved in brain-derived neurotrophic factor (BDNF) effects on fear memory, mood stabilisation and action of several antidepressant drugs. The present study thus explored the impact of Akt2 on behaviour of mice. Behavioural studies (Open-Field, Light-Dark box, O-Maze, Forced Swimming Test, Emergence Test, Object Exploration Test, Morris Water Maze, Radial Maze) have been performed with Akt2 knockout mice (akt(-/-)) and corresponding wild type mice (akt(+/+)). Anxiety and depressive behavior was significantly higher in akt(-/-) than in akt(+/+) mice. The akt(-/-) mice were cognitively unimpaired but displayed increased anxiety in several behavioral tests (O-Maze test, Light-Dark box, Open Field test). Moreover, akt(-/-) mice spent more time floating in the Forced Swimming test, which is a classical feature of experimental depression. Akt2 might be a key factor in the pathophysiology of depression and anxiety. © 2013 S. Karger AG, Basel.

Fluvoxamine moderates reduced voluntary activity following chronic dexamethasone infusion in mice via recovery of BDNF signal cascades.

PubMed

Terada, Kazuki; Izumo, Nobuo; Suzuki, Biora; Karube, Yoshiharu; Morikawa, Tomomi; Ishibashi, Yukiko; Kameyama, Toshiki; Chiba, Koji; Sasaki, Noriko; Iwata, Keiko; Matsuzaki, Hideo; Manabe, Takayuki

2014-04-01

Major depression is a complex disorder characterized by genetic and environmental interactions. Selective serotonin reuptake inhibitors (SSRIs) effectively treat depression. Neurogenesis following chronic antidepressant treatment activates brain derived neurotrophic factor (BDNF) signaling. In this study, we analyzed the effects of the SSRI fluvoxamine (Flu) on locomotor activity and forced-swim behavior using chronic dexamethasone (cDEX) infusions in mice, which engenders depression-like behavior. Infusion of cDEX decreased body weight and produced a trend towards lower locomotor activity during darkness. In the forced-swim test, cDEX-mice exhibited increased immobility times compared with mice administered saline. Flu treatment reversed decreased locomotor activity and mitigated forced-swim test immobility. Real-time polymerase chain reactions using brain RNA samples yielded significantly lower BDNF mRNA levels in cDEX-mice compared with the saline group. Endoplasmic reticulum stress-associated X-box binding protein-1 (XBP1) gene expression was lower in cDEX-mice compared with the saline group. However, marked expression of the XBP1 gene was observed in cDEX-mice treated with Flu compared with mice given saline and untreated cDEX-mice. Expression of 5-HT2A and Sigma-1 receptors decreased after cDEX infusion compared with the saline group, and these decreases normalized to control levels upon Flu treatment. Our results indicate that the Flu moderates reductions in voluntary activity following chronic dexamethasone infusions in mice via recovery of BDNF signal cascades. Copyright © 2014 Elsevier Ltd. All rights reserved.

A possible mechanism for anxiolytic and antidepressant effects of alpha- and beta-amyrin from Protium heptaphyllum (Aubl.) March.

PubMed

Aragão, G F; Carneiro, L M V; Junior, A P F; Vieira, L C; Bandeira, P N; Lemos, T L G; Viana, G S de B

2006-12-01

In the present study, we examined the anxiolytic and antidepressant effects of the mixture of alpha- and beta-amyrin (AMY), pentacyclic triterpenes isolated from the stem bark resin of Protium heptaphyllum. These effects of AMY were demonstrated by the open-field, elevated-plus-maze, rota rod, forced swimming, and pentobarbital-induced sleeping time tests, in mice. In the open-field test, AMY at the doses of 10, 25 and 50 mg/kg, after intraperitoneal or oral administrations, significantly decreased the number of crossings, grooming, and rearing. All these effects were reversed by the pre-treatment with flumazenil (2.5 mg/kg, i.p.), similarly to those observed with diazepam used as a positive standard. In the elevated-plus-maze test, AMY increased the time of permanence and the number of entrances in the open arms. On the contrary, the time of permanence and the number of entrances in the closed arms were decreased. All these effects were also completely reversed by flumazenil, an antagonist of benzodiazepine receptors. In the pentobarbital-induced sleeping time test, AMY at the same doses significantly increased the animals sleeping time duration. In the rota rod test, AMY did not alter motor coordination and, thus, was devoid of effects, as related to controls. Since AMY, at the doses of 10 and 25 mg/kg, showed a sedative effect in the open field test, lower doses (2.5 and 5.0 mg/kg) were used in the forced swimming test, producing a decrease in the immobility time, similarly to that of imipramine, the positive control. The effect of AMI was greater when it was administered 15 min after imipramine (10 mg/kg). However, the antidepressant AMY effects were not altered by the previous administration of paroxetine, a selective blocker of serotonin uptake. In addition, AMY effects in the forced swimming test were totally blocked by reserpine pretreatment, a drug known to induce depletion of biogenic amines. In conclusion, the present work evidenced sedative and anxiolytic effects of AMY that might involve an action on benzodiazepine-type receptors, and also an antidepressant effect where noradrenergic mechanisms will probably play a role.

Individual differences in the forced swimming test and neurochemical kinetics in the rat brain.

PubMed

Sequeira-Cordero, Andrey; Mora-Gallegos, Andrea; Cuenca-Berger, Patricia; Fornaguera-Trías, Jaime

2014-04-10

Individual differences in the forced swimming test (FST) could be associated with differential temporal dynamics of gene expression and neurotransmitter activity. We tested juvenile male rats in the FST and classified the animals into those with low and high immobility according to the amount of immobility time recorded in FST. These groups and a control group which did not undergo the FST were sacrificed either 1, 6 or 24 h after the test. We analyzed the expression of the CRF, CRFR1, BDNF and TrkB in the prefrontal cortex, hippocampus and nucleus accumbens as well as norepinephrine, dopamine, serotonin, glutamate, GABA and glutamine in the hippocampus and nucleus accumbens. Animals with low immobility showed significant reductions of BDNF expression across time points in both the prefrontal cortex and the nucleus accumbens when compared with non-swim control. Moreover, rats with high immobility only showed a significant decrease of BDNF expression in the prefrontal cortex 6h after the FST. Regarding neurotransmitters, only accumbal dopamine turnover and hippocampal glutamate content showed an effect of individual differences (i.e. animals with low and high immobility), whereas nearly all parameters showed significant differences across time points. Correlational analyses suggest that immobility in the FST, probably reflecting despair, is related to prefrontal cortical BDNF and to the kinetics observed in several other neurochemical parameters. Taken together, our results suggest that individual differences observed in depression-like behavior can be associated not only with changes in the concentrations of key neurochemical factors but also with differential time courses of such factors. Copyright © 2014 Elsevier Inc. All rights reserved.

Using Magnetic Forces to Probe the Gravi-response of Swimming Paramecium

NASA Astrophysics Data System (ADS)

Guevorkian, Karine; Valles, James M., Jr.

2004-03-01

Paramecium Caudatum, a single celled ciliate, alters its swimming behavior when subjected to different gravity environments (e.g. centrifugation and micro-gravity). To dissect the mechanisms behind this gravi-response and that of other biological systems, we are developing the use of magnetic body forces as a means of creating a rapidly tunable, simulated variable gravity environment. Since biological materials are weakly diamagnetic, we must subject them to intense inhomogeneous magnetic fields with characteristic field-field gradient products on the order of 16 T^2/cm. We will describe experiments on Paramecium Caudatum in which we adjust their net buoyancy with magnetic forces and measure the resulting changes in their swimming behavior.

Automated Reconstruction of Three-Dimensional Fish Motion, Forces, and Torques

PubMed Central

Voesenek, Cees J.; Pieters, Remco P. M.; van Leeuwen, Johan L.

2016-01-01

Fish can move freely through the water column and make complex three-dimensional motions to explore their environment, escape or feed. Nevertheless, the majority of swimming studies is currently limited to two-dimensional analyses. Accurate experimental quantification of changes in body shape, position and orientation (swimming kinematics) in three dimensions is therefore essential to advance biomechanical research of fish swimming. Here, we present a validated method that automatically tracks a swimming fish in three dimensions from multi-camera high-speed video. We use an optimisation procedure to fit a parameterised, morphology-based fish model to each set of video images. This results in a time sequence of position, orientation and body curvature. We post-process this data to derive additional kinematic parameters (e.g. velocities, accelerations) and propose an inverse-dynamics method to compute the resultant forces and torques during swimming. The presented method for quantifying 3D fish motion paves the way for future analyses of swimming biomechanics. PMID:26752597

Averaged Propulsive Body Acceleration (APBA) Can Be Calculated from Biologging Tags That Incorporate Gyroscopes and Accelerometers to Estimate Swimming Speed, Hydrodynamic Drag and Energy Expenditure for Steller Sea Lions

PubMed Central

Trites, Andrew W.; Rosen, David A. S.; Potvin, Jean

2016-01-01

Forces due to propulsion should approximate forces due to hydrodynamic drag for animals horizontally swimming at a constant speed with negligible buoyancy forces. Propulsive forces should also correlate with energy expenditures associated with locomotion—an important cost of foraging. As such, biologging tags containing accelerometers are being used to generate proxies for animal energy expenditures despite being unable to distinguish rotational movements from linear movements. However, recent miniaturizations of gyroscopes offer the possibility of resolving this shortcoming and obtaining better estimates of body accelerations of swimming animals. We derived accelerations using gyroscope data for swimming Steller sea lions (Eumetopias jubatus), and determined how well the measured accelerations correlated with actual swimming speeds and with theoretical drag. We also compared dive averaged dynamic body acceleration estimates that incorporate gyroscope data, with the widely used Overall Dynamic Body Acceleration (ODBA) metric, which does not use gyroscope data. Four Steller sea lions equipped with biologging tags were trained to swim alongside a boat cruising at steady speeds in the range of 4 to 10 kph. At each speed, and for each dive, we computed a measure called Gyro-Informed Dynamic Acceleration (GIDA) using a method incorporating gyroscope data with accelerometer data. We derived a new metric—Averaged Propulsive Body Acceleration (APBA), which is the average gain in speed per flipper stroke divided by mean stroke cycle duration. Our results show that the gyro-based measure (APBA) is a better predictor of speed than ODBA. We also found that APBA can estimate average thrust production during a single stroke-glide cycle, and can be used to estimate energy expended during swimming. The gyroscope-derived methods we describe should be generally applicable in swimming animals where propulsive accelerations can be clearly identified in the signal—and they should also prove useful for dead-reckoning and improving estimates of energy expenditures from locomotion. PMID:27285467

Re-evaluation of the interrelationships among the behavioral tests in rats exposed to chronic unpredictable mild stress

PubMed Central

Hu, Congli; Luo, Ying; Wang, Hong; Kuang, Shengnan; Liang, Guojuan; Yang, Yang; Mai, Shaoshan; Yang, Junqing

2017-01-01

The chronic unpredictable mild stress model of depression has been widely used as an experimental tool to investigate human psychopathology. Our objective was to provide an update on the validity and reliability of the chronic unpredictable mild stress model, by analyzing the interrelationships among the indexes using stepwise discriminant analysis and Pearson correlation coefficient to examine the possible combinations. We evaluated the depressive rats in both the presence and the absence of chronic unpredictable mild stress, using weight change, percentage of sucrose preference, coat state, splash test, open-field test, elevated plus-maze test, forced swimming test, and Morris water maze test. The results showed that 6-week-long chronic unpredictable mild stress produces significant depression and anxiety-like behavior. The combination of body weight change, percentage of sucrose preference, coat state score, open-field score, grooming latency of splash test, immobility time in force swimming test, and platform crossing in the Morris water maze test can effectively discriminate between normal and chronic unpredictable mild stress rats. Strong interrelationships were noted among these indexes in both open-field test and elevated plus-maze test. In conclusion, there might be certain criteria for the combination of behavioral endpoints, which is advantageous to more effectively and reliably assess the chronic unpredictable mild stress induced depression model. PMID:28931086

Improving the Utility of the CATs Video Cam and Tri-axial Accelerometer for Examining Foraging in Top Marine Predators

DTIC Science & Technology

2015-09-30

measurements of foraging and swimming performance in marine vertebrates. The CATS units are capable of recording motion with 9-degrees of freedom at high...1. Designing of a novel tag holder for tuna telemetry The idea of this novel tag design is to use the hydrodynamic forces appearing when tuna swim ...drag. Increment of the drag force associated with the attached tag was 16% for the simulated speed of swimming 8 m/s. The data obtained are

Fucosterol, a sterol extracted from Sargassum fusiforme, shows antidepressant and anticonvulsant effects.

PubMed

Zhen, Xing-Hua; Quan, Ying-Chun; Jiang, Hai-Ying; Wen, Zheng-Shun; Qu, You-Le; Guan, Li-Ping

2015-12-05

We previously showed that extracts of Sargassum fusiforme significantly reduce immobility time in the forced swim test and tail suspension test, suggesting that these extracts possess antidepressant-like effects. Here, fucosterol extracted from S. fusiforme was evaluated for antidepressant and anticonvulsant activities in mice. Fucosterol (10, 20, 30 and 40mg/kg) significantly shortened immobility time in the forced swim test and tail suspension test for30min after treatment but had no effect on locomotor activity in the open field test. Fucosterol significantly increased serotonin, norepinephrine and the metabolite 5-hydroxyindoleacetic acid in mouse brain, suggesting that the effects of fucosterol may be mediated through these neurotransmitters. As assessed using maximal electroshock, fucosterol (20, 40, 100mg/kg) possessed anticonvulsant activity, whereas rotarod toxicity test results indicated that fucosterol did not induce neurotoxicity at the same dose levels in mice. Thus, fucosterol may be a useful antidepressant adjunct candidate for treating depression in patients with epilepsy. A significant increase in hippocampal brain-derived neurotrophic factor (BDNF) levels was found in the fucosterol 20mg/kg group (P<0.05). Our findings suggested that fucosterol may possess an antidepressant-like effect, which may be mediated by increasing central BDNF levels. Copyright © 2015 Elsevier B.V. All rights reserved.

Possible involvement of ATP-sensitive potassium channels in the antidepressant-like effect of baclofen in mouse forced swimming test.

PubMed

Nazari, Seyedeh Khadijeh; Nikoui, Vahid; Ostadhadi, Sattar; Chegini, Zahra Hadi; Oryan, Shahrbanoo; Bakhtiarian, Azam

2016-12-01

Previous study confirmed that the acute treatment with baclofen by inhibition of the l-arginine-nitric oxide (NO) pathway diminished the immobility behavior in the forced swimming test (FST) of mice. Considering the involvement of NO in adenosine triphosphate (ATP)-sensitive potassium channels (K ATP ), in the present study we investigated the involvement of K ATP channels in antidepressant-like effect of baclofen in the forced swimming test (FST). After assessment of locomotor behavior in the open-field test (OFT), FST was applied for evaluation of the antidepressant-like activity of baclofen in mice. Baclofen at different doses (0.1, 0.3, and 1mg/kg) and fluoxetine (20mg/kg) were administrated by intraperitoneal (ip) route, 30min before the FST or OFT. To clarify the probable involvement of K ATP channels, after determination of sub-effective doses of glibenclamide as a K ATP channel blocker and cromakalim, as an opener of these channels, they were co-administrated with the sub-effective and effective doses of baclofen, respectively. Baclofen at dose 1mg/kg significantly decreased the immobility behavior of mice similar to fluoxetine (20mg/kg). Co-administration of gelibenclamide sub-effective dose (1mg/kg) with baclofen (0.1mg/kg) showed a synergistic antidepressant-like effect in the FST. Also, sub-effective dose of cromakalim (0.1mg/kg) inhibited the antidepressant-like effect of baclofen (1mg/kg) in the FST. All aforementioned treatments had not any impact on the locomotor movement of mice in OFT. Our study for the first time revealed that antidepressant-like effect of baclofen on mice is K ATP -dependent, and baclofen seems that exert this effect by blocking the K ATP channels. Copyright © 2016 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

The hydrodynamics of swimming at intermediate Reynolds numbers in the water boatman (Corixidae).

PubMed

Ngo, Victoria; McHenry, Matthew James

2014-08-01

The fluid forces that govern propulsion determine the speed and energetic cost of swimming. These hydrodynamics are scale dependent and it is unclear what forces matter to the tremendous diversity of aquatic animals that are between a millimeter and a centimeter in length. Animals at this scale generally operate within the regime of intermediate Reynolds numbers, where both viscous and inertial fluid forces have the potential to play a role in propulsion. The present study aimed to resolve which forces create thrust and drag in the paddling of the water boatman (Corixidae), an animal that spans much of the intermediate regime (10

Numerical study on the hydrodynamics of thunniform bio-inspired swimming under self-propulsion.

PubMed

Li, Ningyu; Liu, Huanxing; Su, Yumin

2017-01-01

Numerical simulations are employed to study the hydrodynamics of self-propelled thunniform swimming. The swimmer is modeled as a tuna-like flexible body undulating with kinematics of thunniform type. The wake evolution follows the vortex structures arranged nearly vertical to the forward direction, vortex dipole formation resulting in the propulsion motion, and finally a reverse Kármán vortex street. We also carry out a systematic parametric study of various aspects of the fluid dynamics behind the freely swimming behavior, including the swimming speed, hydrodynamic forces, power requirement and wake vortices. The present results show that the fin thrust as well as swimming velocity is an increasing function of both tail undulating amplitude Ap and oscillating amplitude of the caudal fin θm. Whereas change on the propulsive performance with Ap is associated with the strength of wake vortices and the area of suction region on the fin, the swimming performance improves with θm due to the favorable tilting of the fin that make the pressure difference force more oriented toward the thrust direction. Moreover, the energy loss in the transverse direction and the power requirement increase with Ap but decrease with θm, and this indicates that for achieving a desired swimming speed increasing θm seems more efficiently than increasing Ap. Furthermore, we have compared the current simulations with the published experimental studies on undulatory swimming. Comparisons show that our work tackles the flow regime of natural thunniform swimmers and follows the principal scaling law of undulatory locomotion reported. Finally, this study enables a detailed quantitative analysis, which is difficult to obtain by experiments, of the force production of the thunniform mode as well as its connection to the self-propelled swimming kinematics and vortex wake structure. The current findings help provide insights into the swimming performance and mechanisms of self-propelled thunniform locomotion.

Numerical study on the hydrodynamics of thunniform bio-inspired swimming under self-propulsion

PubMed Central

Li, Ningyu; Liu, Huanxing

2017-01-01

Numerical simulations are employed to study the hydrodynamics of self-propelled thunniform swimming. The swimmer is modeled as a tuna-like flexible body undulating with kinematics of thunniform type. The wake evolution follows the vortex structures arranged nearly vertical to the forward direction, vortex dipole formation resulting in the propulsion motion, and finally a reverse Kármán vortex street. We also carry out a systematic parametric study of various aspects of the fluid dynamics behind the freely swimming behavior, including the swimming speed, hydrodynamic forces, power requirement and wake vortices. The present results show that the fin thrust as well as swimming velocity is an increasing function of both tail undulating amplitude Ap and oscillating amplitude of the caudal fin θm. Whereas change on the propulsive performance with Ap is associated with the strength of wake vortices and the area of suction region on the fin, the swimming performance improves with θm due to the favorable tilting of the fin that make the pressure difference force more oriented toward the thrust direction. Moreover, the energy loss in the transverse direction and the power requirement increase with Ap but decrease with θm, and this indicates that for achieving a desired swimming speed increasing θm seems more efficiently than increasing Ap. Furthermore, we have compared the current simulations with the published experimental studies on undulatory swimming. Comparisons show that our work tackles the flow regime of natural thunniform swimmers and follows the principal scaling law of undulatory locomotion reported. Finally, this study enables a detailed quantitative analysis, which is difficult to obtain by experiments, of the force production of the thunniform mode as well as its connection to the self-propelled swimming kinematics and vortex wake structure. The current findings help provide insights into the swimming performance and mechanisms of self-propelled thunniform locomotion. PMID:28362836

Maximum sustained fin-kick thrust in underwater swimming.

PubMed

Yamaguchi, H; Shidara, F; Naraki, N; Mohri, M

1995-09-01

We examined the upper limit of a diver's fin-kick thrust force using a stationary-swimming ergometer. Heart rate, respiratory minute volume, oxygen uptake, and performance rate were measured in four male subjects who swam constantly for 8 min to maintain a horizontal position against an applied force at a depth of 0.7 m. The water temperature was controlled at 26 degrees +/- 1 degree C. The performance rate, which was the parameter of how well the subjects compensated for the applied load, showed an upper limit around 64 N of sustainable thrust force. This meant that the diver could generate the swimming thrust force within 64 N continuously for 8 min in a steady state. Heart rate, respiratory minute volume, and O2 uptake showed almost proportional increases to the applied load within 64 N and tended to plateau about 69 N.

Effect of confinements: Bending in Paramecium

NASA Astrophysics Data System (ADS)

Eddins, Aja; Yang, Sung; Spoon, Corrie; Jung, Sunghwan

2012-02-01

Paramecium is a unicellular eukaryote which by coordinated beating of cilia, generates metachronal waves which causes it to execute a helical trajectory. We investigate the swimming parameters of the organism in rectangular PDMS channels and try to quantify its behavior. Surprisingly a swimming Paramecium in certain width of channels executes a bend of its flexible body (and changes its direction of swimming) by generating forces using the cilia. Considering a simple model of beam constrained between two walls, we predict the bent shapes of the organism and the forces it exerts on the walls. Finally we try to explain how bending (by sensing) can occur in channels by conducting experiments in thin film of fluid and drawing analogy to swimming behavior observed in different cases.

Maternal neglect with reduced depressive-like behavior and blunted c-fos activation in Brattleboro mothers, the role of central vasopressin.

PubMed

Fodor, Anna; Klausz, Barbara; Pintér, Ottó; Daviu, Nuria; Rabasa, Cristina; Rotllant, David; Balazsfi, Diana; Kovacs, Krisztina B; Nadal, Roser; Zelena, Dóra

2012-09-01

Early mother-infant relationships exert important long-term effects in offspring and are disturbed by factors such as postpartum depression. We aimed to clarify if lack of vasopressin influences maternal behavior paralleled by the development of a depressive-like phenotype. We compared vasopressin-deficient Brattleboro mothers with heterozygous and homozygous normal ones. The following parameters were measured: maternal behavior (undisturbed and separation-induced); anxiety by the elevated plus maze; sucrose and saccharin preference and forced swim behavior. Underlying brain areas were examined by c-fos immunocytochemistry among rest and after swim-stress. In another group of rats, vasopressin 2 receptor agonist was used peripherally to exclude secondary changes due to diabetes insipidus. Results showed that vasopressin-deficient rats spend less time licking-grooming their pups through a centrally driven mechanism. There was no difference between genotypes during the pup retrieval test. Vasopressin-deficient mothers tended to explore more the open arms of the plus maze, showed more preference for sucrose and saccharin and struggled more in the forced swim test, suggesting that they act as less depressive. Under basal conditions, vasopressin-deficient mothers had more c-fos expression in the medial preoptic area, shell of nucleus accumbens, paraventricular nucleus of the hypothalamus and amygdala, but not in other structures. In these areas the swim-stress-induced activation was smaller. In conclusion, vasopressin-deficiency resulted in maternal neglect due to a central effect and was protective against depressive-like behavior probably as a consequence of reduced activation of some stress-related brain structures. The conflicting behavioral data underscores the need for more sex specific studies. Copyright © 2012 Elsevier Inc. All rights reserved.

Effects of prolonged ethanol vapor exposure on forced swim behavior, and neuropeptide Y and corticotropin-releasing factor levels in rat brains.

PubMed

Walker, Brendan M; Drimmer, David A; Walker, Jennifer L; Liu, Tianmin; Mathé, Aleksander A; Ehlers, Cindy L

2010-09-01

Depressive symptoms in alcohol-dependent individuals are well-recognized and clinically relevant phenomena. The etiology has not been elucidated although it is clear that the depressive symptoms may be alcohol independent or alcohol induced. To contribute to the understanding of the neurobiology of chronic ethanol use, we investigated the effects of chronic intermittent ethanol vapor exposure on behaviors in the forced swim test (FST) and neuropeptide Y (NPY) and corticotropin-releasing factor (CRF) levels in specific brain regions. Adult male Wistar rats were subjected to intermittent ethanol vapor (14 h on/10 h off) or air exposure for 2 weeks and were then tested at three time points corresponding to acute withdrawal (8-12 h into withdrawal) and protracted withdrawal (30 and 60 days of withdrawal) in the FST. The behaviors that were measured in the five-min FST consisted of latency to immobility, swim time, immobility time, and climbing time. The FST results showed that the vapor-exposed animals displayed depressive-like behaviors; for instance, decreased latency to immobility in acute withdrawal and decreased latency to immobility, decreased swim time and increased immobility time in protracted withdrawal, with differences between air- and vapor-exposed animals becoming more pronounced over the 60-day withdrawal period. NPY levels in the frontal cortex of the vapor-exposed animals were decreased compared with the control animals, and CRF levels in the amygdala were correlated with increased immobility time. Thus, extended ethanol vapor exposure produced long-lasting changes in FST behavior and NPY levels in the brain. Copyright © 2010 Elsevier Inc. All rights reserved.

Mechanical power, thrust power and propelling efficiency: relationships with elite sprint swimming performance.

PubMed

Gatta, Giorgio; Cortesi, Matteo; Swaine, Ian; Zamparo, Paola

2018-03-01

The purpose of this study was to explore the relationships between mechanical power, thrust power, propelling efficiency and sprint performance in elite swimmers. Mechanical power was measured in 12 elite sprint male swimmers: (1) in the laboratory, by using a whole-body swimming ergometer (W' TOT ) and (2) in the pool, by measuring full tethered swimming force (F T ) and maximal swimming velocity (V max ): W' T  = F T  · V max . Propelling efficiency (η P ) was estimated based on the "paddle wheel model" at V max . V max was 2.17 ± 0.06 m · s -1 , η P was 0.39 ± 0.02, W' T was 374 ± 62 W and W' TOT was 941 ± 92 W. V max was better related to W' T (useful power output: R = 0.943, P < 0.001) than to W' TOT (total power output: R = 0.744, P < 0.01) and this confirms the use of the full tethered test as a valid test to assess power propulsion in sprinters and to estimate swimming performance. The ratio W' T /W' TOT (0.40 ± 0.04) represents the fraction of total mechanical power that can be utilised in water (e.g., η P ) and was indeed the same as that estimated based on the "paddle wheel model"; this supports the use of this model to estimate η P in swimming.

Stressor-Specific Alterations in Corticosterone and Immune Responses in Mice

PubMed Central

Bowers, Stephanie L.; Bilbo, Staci D.; Dhabhar, Firdaus S.; Nelson, Randy J.

2007-01-01

Different stressors likely elicit different physiological and behavioral responses. Previously reported differences in the effects of stressors on immune function may reflect qualitatively different physiological responses to stressors; alternatively, both large and subtle differences in testing protocols and methods among laboratories may make direct comparisons among studies difficult. Here we examine the effects of chronic stressors on plasma corticosterone concentrations, leukocyte redistribution, and skin delayed-type hypersensitivity (DTH) and the effects of acute stressors on plasma corticosterone and leukocyte redistribution. The effects of several commonly used laboratory stressors including restraint, forced swim, isolation, and low ambient temperatures (4°C) were examined. Exposure to each stressor elevated corticosterone concentrations, with restraint (a putative psychological stressor) evoking a significantly higher glucocorticoid response than other stressors. Chronic restraint and forced swim enhanced the DTH response compared to the handled, low temperature, or isolation conditions. Restraint, low temperature, and isolation significantly increased trafficking of lymphocytes and monocytes compared to forced swim or handling. Generally, acute restraint, low temperature, isolation, and handling increased trafficking of lymphocytes and monocytes. Considered together, our results suggest that the different stressors commonly used in psychoneuroimmunology research may not activate the physiological stress response to the same extent. The variation observed in the measured immune responses may reflect differential glucocorticoid activation, differential metabolic adjustments, or both processes in response to specific stressors. PMID:17890050

Swimming of an assembly of rigid spheres at low Reynolds number.

PubMed

Felderhof, B U

2014-11-01

A matrix formulation is derived for the calculation of the swimming speed and the power required for swimming of an assembly of rigid spheres immersed in a viscous fluid of infinite extent. The spheres may have arbitrary radii and may interact with elastic forces. The analysis is based on the Stokes mobility matrix of the set of spheres, defined in low Reynolds number hydrodynamics. For small amplitude, swimming optimization of the swimming speed at given power leads to an eigenvalue problem. The method allows straightforward calculation of the swimming performance of structures modeled as assemblies of interacting rigid spheres.

Predation environment affects boldness temperament of neotropical livebearers.

PubMed

Rasmussen, Josh E; Belk, Mark C

2017-05-01

Behavioral traits of individuals are important phenotypes that potentially interact with many other traits, an understanding of which may illuminate the evolutionary forces affecting populations and species. Among the five axes of temperament is the propensity to behave boldly in the presence of a perceived risk. To determine the effect of different predatorial regimes on boldness and fearfulness, we assessed the behavior of individuals in a novel portable swim chamber (i.e., forced open-field test) by Brachyrhaphis rhabdophora ( n  = 633). We used an information theoretic framework to compare generalized (logistic) linear fixed-effects models of predatorial regime (predator-free [ n  = 6] and predator [ n  = 4] sites), sex, and standard length (SL). Fish from predator sites were much more fearful in the novel arena than fish from nonpredator sites. This varied by length, but not by sex. At 48 mm SL, fish from nonpredator sites were 4.9 times more likely to express bold behavior (ambulation) in the novel swim chamber as fish from predator sites. Probabilities of "ambulating" within the swim chamber increased with size for nonpredator sites and decreased with size for predator sites.

Antidepressant-like activity of resveratrol treatment in the forced swim test and tail suspension test in mice: the HPA axis, BDNF expression and phosphorylation of ERK.

PubMed

Wang, Zhen; Gu, Jianhua; Wang, Xueer; Xie, Kai; Luan, Qinsong; Wan, Nianqing; Zhang, Qun; Jiang, Hong; Liu, Dexiang

2013-11-01

Resveratrol is a natural polyphenol enriched in Polygonum cuspidatum and has diverse biological activities. There is only limited information about the antidepressant-like effect of resveratrol. The present study assessed whether resveratrol treatment (20, 40 and 80mg/kg, i.p., 21days) has an antidepressant-like effect on the forced swim test (FST) and tail suspension test (TST) in mice and examined what its molecular targets might be. The results showed that resveratrol administration produced antidepressant-like effects in mice, evidenced by the reduced immobility time in the FST and TST, while it had no effect on the locomotor activity in the open field test. Resveratrol treatment significantly reduced serum corticosterone levels, which had been elevated by the FST and TST. Moreover, resveratrol increased brain-derived neurotrophic factor (BDNF) protein and extracellular signal-regulated kinase (ERK) phosphorylation levels in the prefrontal cortex and hippocampus. All of these antidepressant-like effects of resveratrol were essentially similar to those observed with the clinical antidepressant, fluoxetine. These results suggest that the antidepressant-like effects of resveratrol in the FST and TST are mediated, at least in part, by modulating hypothalamic-pituitary-adrenal axis, BDNF and ERK phosphorylation expression in the brain region of mice. © 2013.

Swimming and feeding of mixotrophic biflagellates

NASA Astrophysics Data System (ADS)

Dölger, Julia; Nielsen, Lasse Tor; Kiørboe, Thomas; Andersen, Anders

2017-01-01

Many unicellular flagellates are mixotrophic and access resources through both photosynthesis and prey capture. Their fitness depends on those processes as well as on swimming and predator avoidance. How does the flagellar arrangement and beat pattern of the flagellate affect swimming speed, predation risk due to flow-sensing predators, and prey capture? Here, we describe measured flows around two species of mixotrophic, biflagellated haptophytes with qualitatively different flagellar arrangements and beat patterns. We model the near cell flows using two symmetrically arranged point forces with variable position next to a no-slip sphere. Utilizing the observations and the model we find that puller force arrangements favour feeding, whereas equatorial force arrangements favour fast and quiet swimming. We determine the capture rates of both passive and motile prey, and we show that the flow facilitates transport of captured prey along the haptonema structure. We argue that prey capture alone cannot fulfil the energy needs of the observed species, and that the mixotrophic life strategy is essential for survival.

Swimming at small Reynolds number of a planar assembly of spheres in an incompressible viscous fluid with inertia

NASA Astrophysics Data System (ADS)

Felderhof, B. U.

2017-09-01

Translational and rotational swimming at small Reynolds numbers of a planar assembly of identical spheres immersed in an incompressible viscous fluid is studied on the basis of a set of equations of motion for the individual spheres. The motion of the spheres is caused by actuating forces and forces derived from a direct interaction potential, as well as hydrodynamic forces exerted by the fluid as frictional and added mass hydrodynamic interactions. The translational and rotational swimming velocities of the assembly are deduced from momentum and angular momentum balance equations. The mean power required during a period is calculated from an instantaneous power equation. Expressions are derived for the mean swimming velocities and the mean power, valid to second order in the amplitude of displacements from the relative equilibrium positions. Hence these quantities can be evaluated for prescribed periodic displacements. Explicit calculations are performed for three spheres interacting such that they form an equilateral triangle in the rest frame of the configuration.

Experimental studies of protozoan response to intense magnetic fields and forces

NASA Astrophysics Data System (ADS)

Guevorkian, Karine

Intense static magnetic fields of up to 31 Tesla were used as a novel tool to manipulate the swimming mechanics of unicellular organisms. It is shown that homogenous magnetic fields alter the swimming trajectories of the single cell protozoan Paramecium caudatum, by aligning them parallel to the applied field. Immobile neutrally buoyant paramecia also oriented in magnetic fields with similar rates as the motile ones. It was established that the magneto-orientation is mostly due to the magnetic torques acting on rigid structures in the cell body and therefore the response is a non-biological, passive response. From the orientation rate of paramecia in various magnetic field strengths, the average anisotropy of the diamagnetic susceptibility of the cell was estimated. It has also been demonstrated that magnetic forces can be used to create increased, decreased and even inverted simulated gravity environments for the investigation of the gravi-responses of single cells. Since the mechanisms by which Earth's gravity affects cell functioning are still not fully understood, a number of methods to simulate different strength gravity environments, such as centrifugation, have been employed. Exploiting the ability to exert magnetic forces on weakly diamagnetic constituents of the cells, we were able to vary the gravity from -8 g to 10 g, where g is Earth's gravity. Investigations of the swimming response of paramecia in these simulated gravities revealed that they actively regulate their swimming speed to oppose the external force. This result is in agreement with centrifugation experiments, confirming the credibility of the technique. Moreover, the Paramecium's swimming ceased in simulated gravity of 10 g, indicating a maximum possible propulsion force of 0.7 nN. The magnetic force technique to simulate gravity is the only earthbound technique that can create increased and decreased simulated gravities in the same experimental setup. These findings establish a general technique for applying continuously variable forces to cells or cell populations suitable for exploring their force transduction mechanisms.

Evaluation of Anticonvulsant, Antidepressant-, and Anxiolytic-like Effects of an Aqueous Extract from Cultured Mycelia of the Lingzhi or Reishi Medicinal Mushroom Ganoderma lucidum (Higher Basidiomycetes) in Mice.

PubMed

Socala, Katarzyna; Nieoczym, Dorota; Grzywnowicz, Krzysztof; Stefaniuk, Dawid; Wlaz, Piotr

2015-01-01

Ganoderma lucidum is a well-known medicinal mushroom with a long history of use. This study was designed to assess the anticonvulsant potential of an aqueous extract from cultured G. lucidum mycelium in 3 acute seizure models: timed intravenous pentylenetetrazole infusion, maximal electroshock seizure threshold, and 6-Hz-induced psychomotor seizure tests in mice. Moreover, antidepressant-like and anxiolytic-like effects of G. lucidum were evaluated using the forced swim test and the elevated plus maze test in mice, respectively. No changes in seizure thresholds in the intravenous pentylenetetrazole and maximal electroshock seizure threshold tests after acute treatment with G. lucidum extract (200-600 mg/kg) was observed. However, the studied extract (100-400 mg/kg) significantly increased the threshold for psychomotor seizures in the 6-Hz seizure test. In the forced swim test, G. lucidum (100-400 mg/kg) significantly reduced the duration of immobility. No anxiolytic-like or sedative effects were reported in mice pretreated with the extract (400-600 mg/kg). G. lucidum extract (50-2400 mg/kg) did not produce toxic effects in the chimney test (motor coordination) or grip-strength test (neuromuscular strength). Further studies are required to explain the neuropharmacological effects of G. lucidum and to identify its active ingredients that may affect seizure threshold, mood, or anxiety.

The effectiveness of resistive force theory in granular locomotiona)

NASA Astrophysics Data System (ADS)

Zhang, Tingnan; Goldman, Daniel I.

2014-10-01

Resistive force theory (RFT) is often used to analyze the movement of microscopic organisms swimming in fluids. In RFT, a body is partitioned into infinitesimal segments, each of which generates thrust and experiences drag. Linear superposition of forces from elements over the body allows prediction of swimming velocities and efficiencies. We show that RFT quantitatively describes the movement of animals and robots that move on and within dry granular media (GM), collections of particles that display solid, fluid, and gas-like features. RFT works well when the GM is slightly polydisperse, and in the "frictional fluid" regime such that frictional forces dominate material inertial forces, and when locomotion can be approximated as confined to a plane. Within a given plane (horizontal or vertical) relationships that govern the force versus orientation of an elemental intruder are functionally independent of the granular medium. We use the RFT to explain features of locomotion on and within granular media including kinematic and muscle activation patterns during sand-swimming by a sandfish lizard and a shovel-nosed snake, optimal movement patterns of a Purcell 3-link sand-swimming robot revealed by a geometric mechanics approach, and legged locomotion of small robots on the surface of GM. We close by discussing situations to which granular RFT has not yet been applied (such as inclined granular surfaces), and the advances in the physics of granular media needed to apply RFT in such situations.

Chronic caffeine produces sexually dimorphic effects on amphetamine-induced behavior, anxiety and depressive-like behavior in adolescent rats.

PubMed

Turgeon, Sarah M; Townsend, Shannon E; Dixon, Rushell S; Hickman, Emma T; Lee, Sabrina M

2016-04-01

Caffeine consumption has been increasing rapidly in adolescents; however, most research on the behavioral effects of caffeine has been conducted in adults. Two experiments were conducted in which adolescent male and female rats were treated with a moderate dose of caffeine (0.25 g/l) in their drinking water beginning on P26-28. In the first experiment, animals were maintained on caffeinated drinking water or normal tap water for 14 days and were then tested for behavioral and striatal c-Fos response to amphetamine (1.5 mg/kg). In the second experiment, rats were maintained on caffeinated drinking water or normal tap water beginning on P28 and were tested for novel object recognition, anxiety in the light/dark test (L/D) and elevated plus maze (EPM), and depressive like behavior in the forced swim test (FST) beginning on the 14th day of caffeine exposure. Caffeine decreased amphetamine-induced rearing in males, but had no effect in females; however, this behavioral effect was not accompanied by changes in striatal c-Fos, which was increased by amphetamine but not altered by caffeine. No effects of caffeine were observed on novel object recognition or elevated plus maze behavior. However, in the L/D test, there was a sex by caffeine interaction on time spent in the light driven by a caffeine-induced increase in light time in the males but not the females. On the pretest day of the FST, sex by caffeine interactions were observed for swimming and struggling; caffeine decreased struggling behavior and increased swimming behavior in males and caffeine-treated females demonstrated significantly more struggling and significantly less swimming than caffeine-treated males. A similar pattern was observed on the test day in which caffeine decreased immobility overall and increased swimming. These data reveal sex dependent effects of caffeine on behavior in adolescent rats. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of unsteady conditions on propulsion generated by the hand's motion in swimming: a systematic review.

PubMed

Gomes, Lara Elena; Loss, Jefferson Fagundes

2015-01-01

The understanding of swimming propulsion is a key factor in the improvement of performance in this sport. Propulsive forces have been quantified under steady conditions since the 1970s, but actual swimming involves unsteady conditions. Thus, the purpose of the present article was to review the effects of unsteady conditions on swimming propulsion based on studies that have compared steady and unsteady conditions while exploring their methods, their limitations and their results, as well as encouraging new studies based on the findings of this systematic review. A multiple database search was performed, and only those studies that met all eligibility criteria were included. Six studies that compared steady and unsteady conditions using physical experiments or numerical simulations were selected. The selected studies verified the effects of one or more factors that characterise a condition as unsteady on the propulsive forces. Consequently, much research is necessary to understand the effect of each individual variable that characterises a condition as unsteady on swimming propulsion, as well as the effects of these variables as a whole on swimming propulsion.

Adenosine signaling in reserpine-induced depression in rats.

PubMed

Minor, Thomas R; Hanff, Thomas C

2015-06-01

A single, 6 mg/kg intraperitoneal injection of reserpine increased floating time during forced swim testing 24h after administration in rats in five experiments. Although such behavioral depression traditionally is attributed to drug-induced depletion of brain monoamines, we examined the potential contribution of adenosine signaling, which is plausibly activated by reserpine treatment and contributes to behavioral depression in other paradigms. Whereas peripheral administration of the highly selective A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (0.5, 1.0, or 5.0mg/kg i.p.) 15 min before swim testing failed to improve performance in reserpine-treated rats, swim deficits were completely reversed by 7 mg/kg of the nonselective receptor antagonist caffeine. Performance deficits were also reversed by the nonselective A2 antagonist 3,7-dimethylxanthine (0, 0.5, 1.0mg/kg i.p.), and the highly selective A2A receptor antagonist (CSC: 8-(3 chlorostyral)caffeine) (0.01, 0.1, or 1.0mg/kg i.p.) in a dose-dependent manner. The highly selective A2B antagonist alloxazine had no beneficial effect on swim performance at any dose under study (0.1, 1.0, and 5.0mg/kg i.p.). Copyright © 2015 Elsevier B.V. All rights reserved.

Anti-P ribosomal antibodies induce defect in smell capability in a model of CNS -SLE (depression).

PubMed

Katzav, Aviva; Ben-Ziv, Tal; Chapman, Joab; Blank, Miri; Reichlin, Morris; Shoenfeld, Yehuda

2008-12-01

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with more than 100 different autoantibodies, some of which may be associated with specific neuropsychiatric (NPSLE) manifestations. Injection of anti-P ribosomal antibodies (anti-P) directly to the brain ventricles of mice induces depression manifested by increased immobility time in the forced swim test (FST). Mice were injected intracerebroventricularily (ICV) with affinity-purified human anti-P antibodies or normal commercial IgG as control. Mice were examined for depression by the forced swimming test (FST) and for olfactory function by the smell threshold test. Treatments included the antidepressant drug fluoxetine or aroma therapy by exposure to lemon or cinnamon odor. Mice injected with anti-P developed depression-like behavior, which improved significantly upon treatment with fluoxetine. Depressed mice had a significant deficit in olfactory function which was not reversed by fluoxetine. Exposure of anti-P-injected mice to lemon odor was associated with some improvement of the immobility time, a measure of depression. ICV injection of anti-P induces both depression-like behavior and impaired olfactory function in mice. Fluoxetine and possibly lemon odor exposure improve depressive behavior in these mice.

Factors influencing behavior in the forced swim test

PubMed Central

Bogdanova, Olena V.; Kanekar, Shami; D’Anci, Kristen E.; Renshaw, Perry F.

2017-01-01

The forced swim test (FST) is a behavioral test in rodents which was developed in 1978 by Porsolt and colleagues as a model for predicting the clinical efficacy of antidepressant drugs. A modified version of the FST added the classification of active behaviors into swimming and climbing, in order to facilitate the differentiation between serotonergic and noradrenergic classes of antidepressant drugs. The FST is now widely used in basic research and the pharmaceutical screening of potential antidepressant treatments. It is also one of the most commonly used tests to assess depressive-like behavior in animal models. Despite the simplicity and sensitivity of the FST procedure, important differences even in baseline immobility rates have been reported between different groups, which complicate the comparison of results across studies. In spite of several methodological papers and reviews published on the FST, the need still exists for clarification of factors which can influence the procedure. While most recent reviews have focused on antidepressant effects observed with the FST, this one considers the methodological aspects of the procedure, aiming to summarize issues beyond antidepressant action in the FST. The previously published literature is analyzed for factors which are known to influence animal behavior in the FST. These include biological factors, such as strain, age, body weight, gender and individual differences between animals; influence of preconditioning before the FST: handling, social isolation or enriched environment, food manipulations, various kinds of stress, endocrine manipulations and surgery; schedule and routes of treatment, dosage and type of the drugs as well as experimental design and laboratory environmental effects. Consideration of these factors in planning experiments may result in more consistent FST results. PMID:23685235

Anxiolytic and antidepressant profile of the methanolic extract of Piper nigrum fruits in beta-amyloid (1-42) rat model of Alzheimer's disease.

PubMed

Hritcu, Lucian; Noumedem, Jaurès A; Cioanca, Oana; Hancianu, Monica; Postu, Paula; Mihasan, Marius

2015-03-29

Piper nigrum L. (Piperaceae) is employed in traditional medicine of many countries as analgesic, antiinflammatory, anticonvulsant, antioxidant, antidepressant and cognitive-enhancing agent. This study was undertaken in order to evaluate the possible anxiolytic, antidepressant and antioxidant properties of the methanolic extract of Piper nigrum fruits in beta-amyloid (1-42) rat model of Alzheimer's disease. The anxiolytic- and antidepressant-like effects of the methanolic extract were studied by means of in vivo (elevated plus-maze and forced swimming tests) approaches. Also, the antioxidant activity in the amygdala was assessed using superoxide dismutase, glutathione peroxidase and catalase specific activities, the total content of the reduced glutathione, protein carbonyl and malondialdehyde levels. Statistical analyses were performed using one-way analysis of variance (ANOVA). Significant differences were determined by Tukey's post hoc test. F values for which p < 0.05 were regarded as statistically significant. Pearson's correlation coefficient and regression analysis were used in order to evaluate the connection between behavioral measures, the antioxidant defence and lipid peroxidation. The beta-amyloid (1-42)-treated rats exhibited the following: decrease of the exploratory activity, the percentage of the time spent and the number of entries in the open arm within elevated plus-maze test and decrease of swimming time and increase of immobility time within forced swimming test. Administration of the methanolic extract significantly exhibited anxiolytic- and antidepressant-like effects and also antioxidant potential. Taken together, our results suggest that the methanolic extract ameliorates beta-amyloid (1-42)-induced anxiety and depression by attenuation of the oxidative stress in the rat amygdala.

Tualang honey improves memory performance and decreases depressive-like behavior in rats exposed to loud noise stress.

PubMed

Azman, Khairunnuur Fairuz; Zakaria, Rahimah; AbdAziz, CheBadariah; Othman, Zahiruddin; Al-Rahbi, Badriya

2015-01-01

Recent evidence has exhibited dietary influence on the manifestation of different types of behavior induced by stressor tasks. The present study examined the effects of Tualang honey supplement administered with the goal of preventing or attenuating the occurrence of stress-related behaviors in male rats subjected to noise stress. Forty-eight adult male rats were randomly divided into the following four groups: i) nonstressed with vehicle, ii) nonstressed with Tualang honey, iii) stressed with vehicle, and iv) stressed with honey. The supplement was given once daily via oral gavage at 0.2 g/kg body weight. Two types of behavioral tests were performed, namely, the novel object recognition test to evaluate working memory and the forced swimming test to evaluate depressive-like behavior. Data were analyzed by a two-way analysis of variance (ANOVA) using IBM SPSS 18.0. It was observed that the rats subjected to noise stress expressed higher levels of depressive-like behavior and lower memory functions compared to the unexposed control rats. In addition, our results indicated that the supplementation regimen successfully counteracted the effects of noise stress. The forced swimming test indicated that climbing and swimming times were significantly increased and immobility times significantly decreased in honey-supplemented rats, thereby demonstrating an antidepressant-like effect. Furthermore, cognitive function was shown to be intensely affected by noise stress, but the effects were counteracted by the honey supplement. These findings suggest that subchronic exposure to noise stress induces depressive-like behavior and reduces cognitive functions, and that these effects can be attenuated by Tualang honey supplementation. This warrants further studies to examine the role of Tulang honey in mediating such effects.

Tualang honey improves memory performance and decreases depressive-like behavior in rats exposed to loud noise stress

PubMed Central

Azman, Khairunnuur Fairuz; Zakaria, Rahimah; AbdAziz, CheBadariah; Othman, Zahiruddin; Al-Rahbi, Badriya

2015-01-01

Recent evidence has exhibited dietary influence on the manifestation of different types of behavior induced by stressor tasks. The present study examined the effects of Tualang honey supplement administered with the goal of preventing or attenuating the occurrence of stress-related behaviors in male rats subjected to noise stress. Forty-eight adult male rats were randomly divided into the following four groups: i) nonstressed with vehicle, ii) nonstressed with Tualang honey, iii) stressed with vehicle, and iv) stressed with honey. The supplement was given once daily via oral gavage at 0.2 g/kg body weight. Two types of behavioral tests were performed, namely, the novel object recognition test to evaluate working memory and the forced swimming test to evaluate depressive-like behavior. Data were analyzed by a two-way analysis of variance (ANOVA) using IBM SPSS 18.0. It was observed that the rats subjected to noise stress expressed higher levels of depressive-like behavior and lower memory functions compared to the unexposed control rats. In addition, our results indicated that the supplementation regimen successfully counteracted the effects of noise stress. The forced swimming test indicated that climbing and swimming times were significantly increased and immobility times significantly decreased in honey-supplemented rats, thereby demonstrating an antidepressant-like effect. Furthermore, cognitive function was shown to be intensely affected by noise stress, but the effects were counteracted by the honey supplement. These findings suggest that subchronic exposure to noise stress induces depressive-like behavior and reduces cognitive functions, and that these effects can be attenuated by Tualang honey supplementation. This warrants further studies to examine the role of Tulang honey in mediating such effects. PMID:25774610

Immobility time during the forced swimming test predicts sensitivity to amitriptyline, whereas traveled distance in the circular corridor indicates resistance to treatment in female Wistar rats.

PubMed

Flores-Serrano, Ana G; Zaldívar-Rae, Jaime; Salgado, Humberto; Pineda, Juan C

2015-03-25

Among the main issues in the pharmacological treatment of depression are the wide variation in response to antidepressants among individual patients and the lack of indexes that allow prediction of which drug will be effective in a particular case. We evaluated whether differential sensitivity to amitriptyline is related to dichotomous categorization of individuals on the basis of their behavioral responses to two common paradigms used to evaluate the potential of tricyclic drugs as antidepressants. Hence, we categorized a cohort of 38 female rats on the basis of their immobility time in the conditioning phase of the forced swimming test [FST; high immobility (HI) vs. low immobility (LI) rats] and their locomotor behavior in the circular corridor test [high locomotor response (HR) vs. low locomotor response (LR) rats]. We subjected the rodents to the FST while under the influence of vehicle (n=20) or amitriptyline (15 mg/kg; n=18). We found no statistical evidence of dependence between categorizations of rats on the basis of their behavior in the FST and circular corridor test. Rats categorized as HI/LI and HR/LR significantly differed in their sensitivity/resistance to amitriptyline, as evidenced by changes (or lack thereof) in their immobility time, climbing time, and swimming time during the FST. These results confirm that different behavioral styles among rats are linked to differential sensitivity/resistance to antidepressants. However, we specifically found that categorizing rats as HI/LI better reflected sensitivity to amitriptyline, whereas categorizing them as HR/LR better revealed resistance to the drug. These differential responses should be considered in experimental approaches. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

Self-propelled swimming simulations of bio-inspired smart structures.

PubMed

Daghooghi, Mohsen; Borazjani, Iman

2016-08-09

This paper presents self-propelled swimming simulations of a foldable structure, whose folded configuration is a box. For self-locomotion through water the structure unfolds and undulates. To guide the design of the structure and understand how it should undulate to achieve either highest speed or maximize efficiency during locomotion, several kinematic parameters were systematically varied in the simulations: the wave type (standing wave versus traveling wave), the smoothness of undulations (smooth undulations versus undulations of rigid links), the mode of undulations (carangiform: mackerel-like versus anguilliform: eel-like undulations), and the maximum amplitude of undulations. We show that the swimmers with standing wave are slow and inefficient because they are not able to produce thrust using the added-mass mechanism. Among the tested types of undulation at low Reynolds number (Re) regime of [Formula: see text] (Strouhal number of about 1.0), structures that employ carangiform undulations can swim faster, whereas anguilliform swimmers are more economic, i.e., using less power they can swim a longer distance. Another finding of our simulations is that structures which are made of rigid links are typically less efficient (lower propulsive and power efficiencies and also lower swimming speed) compared with smoothly undulating ones because a higher added-mass force is generated by smooth undulations. The wake of all the swimmers bifurcated at the low Re regime because of the higher lateral relative to the axial velocity (high Strouhal number) that advects the vortices laterally creating a double row of vortices in the wake. In addition, we show that the wake cannot be used to predict the performance of the swimmers because the net force in each cycle is zero for self-propelled bodies and the pressure term is not negligible compared to the other terms.

Enhanced anti-immobility effects of Sanggenon G isolated from the root bark of Morus alba combined with the α2-antagonist yohimbine in the rat forced swim test.

PubMed

Lim, Dong Wook; Baek, Nam-In; Kim, Yun Tai; Lee, Changho; Kim, In-Ho; Han, Daeseok

2016-07-01

In this study, we aimed to determine whether Sanggenon G, an active compound isolated from the root bark of Morus alba, exhibited enhanced anti-immobility activity with the addition of the α2-antagonist yohimbine in rats subjected to forced swim test (FST)-induced depression. Fluoxetine (a selective serotonin reuptake inhibitor) treatment in rats reduced the immobility time, and pretreatment with yohimbine significantly enhanced the antidepressant-like behavior of fluoxetine at 5, 10 and 20 mg/kg. Similarly, Sanggenon G significantly decreased the immobility time, reducing immobility by a maximum of 43.9 % when treated at a dose of 20 mg/kg. Furthermore, pretreatment with yohimbine significantly enhanced the antidepressant-like behavior of Sanggenon G at 5 and 10 mg/kg. Our findings suggest that the antidepressant-like effect of Sanggenon G could be facilitated by concomitant use of the α2-antagonist. Further studies are needed to evaluate the potential of Sanggenon G as an alternative therapeutic approach for the treatment of depression.

Antidepressant-like effect of fluoxetine may depend on translocator protein activity and pretest session duration in forced swimming test in mice.

PubMed

Kudryashov, Nikita V; Kalinina, Tatiana S; Shimshirt, Alexander A; Korolev, Anton O; Volkova, Anna V; Voronina, Tatiana A

2018-06-01

The antidepressant-like effect of fluoxetine (20 mg/kg i.p.) has been assessed using the forced swimming test (FST) in IRC (CD-1) mice exposed or not to a pretest session of different duration (5 or 20 min). The influence of the mitochondrial translocator protein (TSPO) activity on the antidepressant-like effect of fluoxetine (20 mg/kg i.p.) in the FST was also studied. The antidepressant-like effect of fluoxetine was observed only in mice subjected to a 5-min pretest session 24 h before the FST. The TSPO antagonist PK11195 [1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide; 1 or 3 mg/kg i.p.] inhibited the antidepressant activity of fluoxetine in the FST. In the present study, fluoxetine or PK11195 was administered for a short duration. We suppose that the functional activity of TSPO may depend on a pretest session and that using this procedure is necessary to detect antidepressant activity of fluoxetine-like drugs.

Automated motile cell capture and analysis with optical traps.

PubMed

Shao, Bing; Nascimento, Jaclyn M; Shi, Linda Z; Botvinick, Elliot L

2007-01-01

Laser trapping in the near infrared regime is a noninvasive and microfluidic-compatible biomedical tool. This chapter examines the use of optical trapping as a quantitative measure of sperm motility. The single point gradient trap is used to directly measure the swimming forces of sperm from several different species. These forces could provide useful information about the overall sperm motility and semen quality. The swimming force is measured by trapping sperm and subsequently decreasing laser power until the sperm is capable of escaping the trap. Swimming trajectories were calculated by custom built software, an automatic sperm tracking algorithm called the single sperm tracking algorithm or SSTA. A real-time automated tracking and trapping system, or RATTS, which operates at video rate, was developed to perform experiments with minimal human involvement. After the experimenter initially identifies and clicks the computer mouse on the sperm-of-interest, RATTS performs all further tracking and trapping functions without human intervention. Additionally, an annular laser trap which is potentially useful for high-throughput sperm sorting based on motility and chemotaxis was developed. This low power trap offers a more gentle way for studying the effects of laser radiation, optical force, and external obstacles on sperm swimming pattern.

Performance evaluation of an improved fish robot actuated by piezoceramic actuators

NASA Astrophysics Data System (ADS)

Nguyen, Q. S.; Heo, S.; Park, H. C.; Byun, D.

2010-03-01

This paper presents an improved fish robot actuated by four lightweight piezocomposite actuators. Our newly developed actuation mechanism is simple to fabricate because it works without gears. With the new actuation mechanism, the fish robot has a 30% smaller cross section than our previous model. Performance tests of the fish robot in water were carried out to measure the tail-beat angle, the thrust force, the swimming speed for various tail-beat frequencies from 1 to 5 Hz and the turning radius at the optimal frequency. The maximum swimming speed of the fish robot is 7.7 cm s - 1 at a tail-beat frequency of 3.9 Hz. A turning experiment shows that the swimming direction of the fish robot can be controlled by changing the duty ratio of the driving voltage; the fish robot has a turning radius of 0.41 m for a left turn and 0.68 m for a right turn.

Cruise and turning performance of an improved fish robot actuated by piezoceramic actuators

NASA Astrophysics Data System (ADS)

Nguyen, Quang Sang; Heo, Seok; Park, Hoon Cheol; Goo, Nam Seo; Byun, Doyoung

2009-03-01

The purpose of this study is improvement of a fish robot actuated by four light-weight piezocomposite actuators (LIPCAs). In the fish robot, we developed a new actuation mechanism working without any gear and thus the actuation mechanism was simple in fabrication. By using the new actuation mechanism, cross section of the fish robot became 30% smaller than that of the previous model. Performance tests of the fish robot in water were carried out to measure tail-beat angle, thrust force, swimming speed and turning radius for tail-beat frequencies from 1Hz to 5Hz. The maximum swimming speed of the fish robot was 7.7 cm/s at 3.9Hz tail-beat frequency. Turning experiment showed that swimming direction of the fish robot could be controlled with 0.41 m turning radius by controlling tail-beat angle.

Hydrodynamic Attraction of Swimming Microorganisms by Surfaces

NASA Astrophysics Data System (ADS)

Berke, Allison P.; Turner, Linda; Berg, Howard C.; Lauga, Eric

2008-07-01

Cells swimming in confined environments are attracted by surfaces. We measure the steady-state distribution of smooth-swimming bacteria (Escherichia coli) between two glass plates. In agreement with earlier studies, we find a strong increase of the cell concentration at the boundaries. We demonstrate theoretically that hydrodynamic interactions of the swimming cells with solid surfaces lead to their reorientation in the direction parallel to the surfaces, as well as their attraction by the closest wall. A model is derived for the steady-state distribution of swimming cells, which compares favorably with our measurements. We exploit our data to estimate the flagellar propulsive force in swimming E. coli.

The reliability of an instrumented start block analysis system.

PubMed

Tor, Elaine; Pease, David L; Ball, Kevin A

2015-02-01

The swimming start is highly influential to overall competition performance. Therefore, it is paramount to develop reliable methods to perform accurate biomechanical analysis of start performance for training and research. The Wetplate Analysis System is a custom-made force plate system developed by the Australian Institute of Sport--Aquatic Testing, Training and Research Unit (AIS ATTRU). This sophisticated system combines both force data and 2D digitization to measure a number of kinetic and kinematic parameter values in an attempt to evaluate start performance. Fourteen elite swimmers performed two maximal effort dives (performance was defined as time from start signal to 15 m) over two separate testing sessions. Intraclass correlation coefficients (ICC) were used to determine each parameter's reliability. The kinetic parameters all had ICC greater than 0.9 except the time of peak vertical force (0.742). This may have been due to variations in movement initiation after the starting signal between trials. The kinematic and time parameters also had ICC greater than 0.9 apart from for the time of maximum depth (0.719). This parameter was lower due to the swimmers varying their depth between trials. Based on the high ICC scores for all parameters, the Wetplate Analysis System is suitable for biomechanical analysis of swimming starts.

Antidepressant-like effects induced by NMDA receptor blockade and NO synthesis inhibition in the ventral medial prefrontal cortex of rats exposed to the forced swim test.

PubMed

Pereira, Vitor Silva; Romano, Angélica; Wegener, Gregers; Joca, Sâmia R L

2015-07-01

Systemic treatment with NMDA receptor (NMDAR) antagonists, inhibitors of neuronal nitric oxide synthase (nNOS) or of soluble guanylyl cyclase (sGC), induce antidepressant-like effects in rats. Increased levels of glutamate and nitric oxide (NO) in the medial prefrontal cortex (MPFC) of stressed animals have been described in the literature. However, the role of the NMDAR-nNOS-sGC pathway of the MPFC in the mediation of forced swim-induced behaviors remains unclear. The aim of this work was to test the hypothesis that the inhibition of the NMDAR-nNOS-sGC pathway in the ventral MPFC (infralimbic (IL) or prelimbic (PL)) would elicit antidepressant-like effects in the forced swim test (FST). Rats implanted with cannulae aimed at the PL or the IL were exposed to the FST and injected with LY235959 (NMDAR antagonist), NPA (nNOS inhibitor), ODQ (sGC inhibitor), or carboxy-PTIO (NO scavenger). Additional groups received the AMPA antagonist, NBQX, before the effective doses of LY235959 or NPA. LY235959 administration into PL or IL before the FS pretest produced no effects. Administration of LY235959 (3 and 10 nmol/0.2 μL) after pretest was effective only when administered into the PL. However, the administration of NPA (0.01 nmol/0.2 μL), c-PTIO (1.0 nmol/0.2 μL), and ODQ (1.0 nmol/0.2 μL) into the PL or IL before the FST produced antidepressant-like effects. NBQX blocked the antidepressant-like effect of LY235959 but not of NPA. Blocking NMDAR or NO signaling in the vMPFC, either in the IL or the PL, induces antidepressant-like effects in the rat FST. These effects seemingly occur through independent mechanisms, since NBQX blocked the former effect but not the latter.

Sex differences in depression-like behavior after nerve injury are associated with differential changes in brain-derived neurotrophic factor levels in mice subjected to early life stress.

PubMed

Nishinaka, Takashi; Kinoshita, Megumi; Nakamoto, Kazuo; Tokuyama, Shogo

2015-04-10

We recently demonstrated that exposure to early life stress exacerbates nerve injury-induced thermal and mechanical hypersensitivity in adult male and female mice. Accumulating evidence suggests that chronic pain causes emotional dysfunction, such as anxiety and depression. In the present study, we investigated the impact of early life stress on depression-like behavior after nerve injury in mice. In addition, we examined the expression of brain-derived neurotrophic factor (BDNF), which is known to be involved in the pathogenesis of depression. Early life stress was induced by maternal separation between 2 and 3 weeks of age combined with social isolation after weaning (MSSI). At 9 weeks of age, the sciatic nerve was partially ligated to elicit neuropathic pain. Depression-like behavior was evaluated using the forced swim test at 12 weeks of age. Tissue samples from different regions of the brain were collected at the end of maternal separation (3 weeks of age) or after the forced swim test (12 weeks of age). At 12 weeks of age, immobility time in the forced swim test was increased only in MSSI-stressed female mice with nerve injury. BDNF expression was increased in male, but not female, MSSI-stressed mice at 3 weeks of age. However, MSSI stress did not impact BDNF expression in male or female mice at 12 weeks of age. Our findings suggest that exposure to early life stress exacerbates emotional dysfunction induced by neuropathic pain in a sex-dependent manner. Changes in BDNF expression after early life stress may be associated with neuropathic pain-induced depression-like behavior in adulthood. Furthermore, sex differences in BDNF expression after exposure to early life stress may contribute to sex-specific susceptibility to neuropathic pain-induced emotional dysfunction. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Non-invasive measurement of instantaneous forces during aquatic locomotion: a case study of the bluegill sunfish pectoral fin.

PubMed

Peng, Jifeng; Dabiri, John O; Madden, Peter G; Lauder, George V

2007-02-01

Swimming and flying animals generate unsteady locomotive forces by delivering net momentum into the fluid wake. Hence, swimming and flying forces can be quantified by measuring the momentum of animal wakes. A recently developed model provides an approach to empirically deduce swimming and flying forces based on the measurement of velocity and vortex added-mass in the animal wake. The model is contingent on the identification of the vortex boundary in the wake. This paper demonstrates the application of that method to a case study quantifying the instantaneous locomotive forces generated by the pectoral fins of the bluegill sunfish (Lepomis macrochirus Rafinesque), measured using digital particle image velocimetry (DPIV). The finite-time Lyapunov exponent (FTLE) field calculated from the DPIV data was used to determine the wake vortex boundary, according to recently developed fluid dynamics theory. Momentum of the vortex wake and its added-mass were determined and the corresponding instantaneous locomotive forces were quantified at discrete time points during the fin stroke. The instantaneous forces estimated in this study agree in magnitude with the time-averaged forces quantified for the pectoral fin of the same species swimming in similar conditions and are consistent with the observed global motion of the animals. A key result of this study is its suggestion that the dynamical effect of the vortex wake on locomotion is to replace the real animal fin with an ;effective appendage', whose geometry is dictated by the FTLE field and whose interaction with the surrounding fluid is wholly dictated by inviscid concepts from potential flow theory. Benefits and limitations of this new framework for non-invasive instantaneous force measurement are discussed, and its application to comparative biomechanics and engineering studies is suggested.

Young coconut water ameliorates depression via modulation of neurotransmitters: possible mechanism of action.

PubMed

Rao, Sadia Saleem; Najam, Rahila

2016-10-01

In the current era, plants are frequently tested for its antidepressant potential. Therefore young coconut water, a commonly used plant based beverage, was selected to explore its antidepressant potential. Rodents were selected for this study and forced swim test was conducted to explore antidepressant activity. Analysis of brain biogenic amines using high performance liquid chromatography coupled with electrochemical detection and potentiation of noradrenaline toxicity model were also incorporated in this study to demonstrate probable antidepressant mechanism of action. Coconut water was administered orally at the dose of 4 ml/100 g. Young coconut water showed highly significant increase in struggling time (p < 0.001) in forced swim test. This suggests antidepressant effect of young coconut water. In noradrenaline toxicity model, it was observed that young coconut water is not a good adrenergic component as its lethality percentage in this test was observed 0 % unlike imipramine which showed lethality of 100 %. High performance liquid chromatography-electrochemical detection of rodent's brain revealed decline in 5-hydroxytryptamine, noradrenaline and dopamine, with concomitant decline in metabolites 5-hydroxyindoleacetic acid, 3,4-dihydroxyphenylacetic acid, homovanillic acid and increase in 5-hydroxyindoleacetic acid/5-hydroxytryptamine ratio. Findings from the exploration of monoamines suggest antidepressant effect of young coconut water via homeostasis of monoamines synthesis.

Relationship between different push-off variables and start performance in experienced swimmers.

PubMed

García-Ramos, Amador; Feriche, Belén; de la Fuente, Blanca; Argüelles-Cienfuegos, Javier; Strojnik, Vojko; Strumbelj, Boro; Štirn, Igor

2015-01-01

The objective of this study was to determine the relationship between different variables measured with a force plate during the swimming start push-off phase and start performance presented by times to 5, 10 and 15 m. Twenty-one women from the Slovenian national swimming team performed two different swim starts (freestyle and undulatory) on a portable force plate to a distance further than 15 m. Correlations between push-off variables and times to 5, 10 and 15 m were quantified through Pearson's product-moment correlation coefficient (r). The variables that significantly correlated (p < .05) to all times measured in the two starts performed were: average horizontal acceleration (freestyle: r = -0.58 to -0.71; and undulatory: r = -0.55 to -0.66), horizontal take-off velocity (freestyle: r = -0.56 to -0.69; and undulatory: r = -0.53 to -0.67) and resultant take-off velocity (freestyle: r = -0.53 to -0.65; and undulatory: r = -0.52 to -0.61). None of the variables derived from the vertical force were correlated to swimming start performance (p > .05). Based on the results of this study, we can conclude that horizontal take-off velocity and average horizontal acceleration (calculated as the average horizontal force divided by swimmer's body mass) are the variables most related to swimming start performance in experienced swimmers, and therefore could be the preferred measures to monitor swimmers' efficiency during the push-off phase.

Anxiolytic effects of buspirone and MTEP in the Porsolt Forced Swim Test.

PubMed

Lee, Kaziya M; Coelho, Michal A; Sern, Kimberly R; Class, MacKayla A; Bocz, Mark D; Szumlinski, Karen K

2017-01-01

Traditionally, a reduction in floating behavior or immobility in the Porsolt forced swim test (FST) is employed as a predictor of antidepressant efficacy. However, over the past several years, our studies of alcohol withdrawal-induced negative affect consistently indicate the coincidence of increased anxiety-related behaviors on various behavioral tests with reduced immobility in the FST. Further, this behavioral profile correlates with increased mGlu5 protein expression within limbic brain regions. As the role for mGlu5 in anxiety is well established, we hypothesized that the reduced immobility exhibited by alcohol-withdrawn mice when tested in the FST might reflect anxiety, possibly a hyper-reactivity to the acute swim stressor. Herein, we evaluated whether or not the decreased FST immobility during alcohol withdrawal responds to systemic treatment with a behaviorally-effective dose of the prototypical anxiolytic, buspirone (5 mg/kg). We also determined the functional relevance of the withdrawal-induced increase in mGlu5 expression for FST behavior by comparing the effects of buspirone to a behaviorally effective dose of the mGlu5 negative allosteric modulator MTEP (3 mg/kg). Adult male C57BL/6J mice were subjected to a 14-day, multi-bottle, binge-drinking protocol that elicits hyper-anxiety and increases glutamate-related protein expression during early withdrawal. Control animals received only water. At 24hr withdrawal, animals from each drinking condition were subdivided into groups and treated with an IP injection of buspirone, MTEP, or vehicle, 30min prior to the FST. Drug effects on general locomotor activity were also assessed. As we reported previously, alcohol-withdrawn animals exhibited significantly reduced immobility in the FST compared to water controls. Both buspirone and MTEP significantly increased immobility in alcohol-withdrawn animals, with a modest increase also seen in water controls. No significant group differences were observed for locomotor activity, indicating that neither anxiolytic was sedating. These results provide predictive validity for increased swimming/reduced immobility in the FST as a model of anxiety and provide novel evidence in favor of mGlu5 inhibition as an effective therapeutic strategy for treating hyperanxiety during alcohol withdrawal.

Characteristics of undulatory locomotion in granular media

NASA Astrophysics Data System (ADS)

Peng, Zhiwei; Pak, On Shun; Elfring, Gwynn J.

2016-03-01

Undulatory locomotion is ubiquitous in nature and observed in different media, from the swimming of flagellated microorganisms in biological fluids, to the slithering of snakes on land, or the locomotion of sandfish lizards in sand. Despite the similarity in the undulating pattern, the swimming characteristics depend on the rheological properties of different media. Analysis of locomotion in granular materials is relatively less developed compared with fluids partially due to a lack of validated force models but recently a resistive force theory in granular media has been proposed and shown useful in studying the locomotion of a sand-swimming lizard. Here we employ the proposed model to investigate the swimming characteristics of a slender filament, of both finite and infinite length, undulating in a granular medium and compare the results with swimming in viscous fluids. In particular, we characterize the effects of drifting and pitching in terms of propulsion speed and efficiency for a finite sinusoidal swimmer. We also find that, similar to Lighthill's results using resistive force theory in viscous fluids, the sawtooth swimmer is the optimal waveform for propulsion speed at a given power consumption in granular media. The results complement our understanding of undulatory locomotion and provide insights into the effective design of locomotive systems in granular media.

Self-propelled anguilliform swimming: simultaneous solution of the two-dimensional navier-stokes equations and Newton's laws of motion

PubMed

Carling; Williams; Bowtell

1998-12-01

Anguilliform swimming has been investigated by using a computational model combining the dynamics of both the creature's movement and the two-dimensional fluid flow of the surrounding water. The model creature is self-propelled; it follows a path determined by the forces acting upon it, as generated by its prescribed changing shape. The numerical solution has been obtained by applying coordinate transformations and then using finite difference methods. Results are presented showing the flow around the creature as it accelerates from rest in an enclosed tank. The kinematics and dynamics associated with the creature's centre of mass are also shown. For a particular set of body shape parameters, the final mean swimming speed is found to be 0.77 times the speed of the backward-travelling wave. The corresponding movement amplitude envelope is shown. The magnitude of oscillation in the net forward force has been shown to be approximately twice that in the lateral force. The importance of allowing for acceleration and deceleration of the creature's body (rather than imposing a constant swimming speed) has been demonstrated. The calculations of rotational movement of the body and the associated moment of forces about the centre of mass have also been included in the model. The important role of viscous forces along and around the creature's body and in the growth and dissolution of the vortex structures has been illustrated.

Biomechanical and structural parameters of tendons in rats subjected to swimming exercise.

PubMed

Bezerra, M A; Santos de Lira, K D; Coutinho, M P G; de Mesquita, G N; Novaes, K A; da Silva, R T B; de Brito Nascimento, A K; Inácio Teixeira, M F H B; Moraes, S R A

2013-12-01

The aim of this study was to evaluate the effect of swimming exercise, without overloading, on the biomechanical parameters of the calcaneal tendon of rats. 27 male Wistar rats (70 days) were distributed randomly into 2 groups, Control Group (CG; n=15) with restricted movements inside the cage and Swimming Group (SG; n=12), subjected to exercise training in a tank with a water temperature of 30±1°C, for 1 h/day, 5 days/week for 8 weeks. All animals were kept in a reversed light/dark cycle of 12 h with access to food and water ad libitum. After that, they were anesthetized and had their calcaneus tendons collected from their left rear paws. The tendon was submitted to a mechanical test on a conventional test machine. From the stress vs. strain curve, the biomechanical data were analyzed. For the statistical analysis, the Student-T test was used (p<0.05). Of the variables examined, the maximum tension (p=0.009), maximum force (p=0.03), energy of deformation/tendon cross sectional area (p=0.017) and elastic modulus of the tendon (p=0.013) showed positive outcomes in SG. There was no difference in the other parameters. The results indicate that the swimming exercise training, without overloading, was an important stimulus for improving the biomechanical parameters and structural properties of the calcaneal tendon. © Georg Thieme Verlag KG Stuttgart · New York.

Effects of MK-886, a 5-lipoxygenase activating protein (FLAP) inhibitor, and 5-lipoxygenase deficiency on the forced swimming behavior of mice

PubMed Central

Uz, Tolga; Dimitrijevic, Nikola; Imbesi, Marta; Manev, Hari; Manev, Radmila

2008-01-01

A common biological pathway may contribute to the comorbidity of atherosclerosis and depression. Increased activity of the enzymatic 5-lipoxygenase (5-LOX; 5LO) pathway is a contributing factor in atherosclerosis and a 5-LOX inhibitor, MK-886, is beneficial in animal models of atherosclerosis. In the brain, MK-886 increases phosphorylation of the glutamate receptor subunit GluR1, and the increased phosphorylation of this receptor has been associated with antidepressant treatment. In this work, we evaluated the behavioral effects of MK-886 in an automated assay of mouse forced swimming, which identifies antidepressant activity as increased climbing behavior and/or decreased rest time. Whereas a single injection of MK-886 (3 and 10 mg/kg) did not affect forced swimming behaviors assayed 30 min later, 6 daily injections of 3 mg/kg MK-886 slightly increased climbing and significantly reduced rest time in wild-type mice but not in 5-LOX-deficient mice. A diet delivery of MK-886, 4 μg per 100 mg body-weight per day, required three weeks to affect forced swimming; it increased climbing behavior. Climbing behavior was also increased in naive 5-LOX-deficient mice compared to naive wild-type controls. These results suggest that 5-LOX inhibition and deficiency may be associated with antidepressant activity. Increased climbing in a forced swimming assay is a typical outcome of antidepressants that increase noradrenergic and dopaminergic activity. Interestingly, 5-LOX deficiency and MK-886 treatment have been shown to be capable of increasing the behavioral effects of a noradrenaline/dopamine-potentiating drug, cocaine. Future research is needed to evaluate the clinical relevance of our findings. PMID:18403121

Behavioral Sequelae Following Acute Diisopropylfluorophosphate Intoxication in Rats: Comparative Effects of Atropine and Cannabinomimetics

PubMed Central

Wright, Linnzi K. M.; Liu, Jing; Nallapaneni, Anuradha; Pope, Carey N.

2010-01-01

The comparative effects of atropine and the indirect cannabinomimetics URB597 (a fatty acid amide hydrolase inhibitor) and URB602 (a monoacylglycerol lipase inhibitor) on functional and neurobehavioral endpoints following acute diisopropylfluorophosphate intoxication were studied. Male Sprague-Dawley rats were treated with vehicle or DFP (2.5 mg/kg, sc), immediately post-treated with either vehicle, atropine (16 mg/kg), URB597 (3 mg/kg), URB602 (10 mg/kg) or a combination of URB597 and URB602, and functional signs of toxicity as well as nocturnal motor activity were measured daily for seven consecutive days. Performance in the elevated plus maze (for anxiety-like behavior) and the forced swimming test (for depression-like behavior) was measured at days 6-8 and 27-29 after dosing. Twenty-four hours after dosing, DFP markedly reduced cholinesterase activity in selected brain regions and peripheral tissues (diaphragm and plasma). Substantial recovery of cholinesterase activity was noted at both 8 and 29 days after dosing but significant inhibition was still noted in some brain regions at the latest time-point. DFP elicited body weight reductions and typical signs of cholinergic toxicity, and reduced nocturnal ambulation and rearing. Atropine and the cannabinomimetics (alone and in combination) partially attenuated DFP-induced functional signs of toxicity. None of the post-treatments reversed the DFP-induced reduction in ambulation or rearing, however. No significant treatment-related effects on elevated plus maze performance were noted. DFP-treated rats exhibited decreased swimming and increased immobility in the forced swimming test at both time-points. None of the post-treatments had any effect on DFP-induced changes in immobility or swimming at day 8. At day 29, atropine and the combination of URB597/URB602 significantly blocked DFP-induced changes in immobility, while URB597 and the combination reversed DFP-induced changes in swimming. The results suggest that early blockade of muscarinic receptors and enhancement of eCB signaling can attenuate both acute and delayed effects elicited by DFP. PMID:20034559

Spiral swimming of an artificial micro-swimmer

NASA Astrophysics Data System (ADS)

Keaveny, Eric E.; Maxey, Martin R.

A device constructed from a filament of paramagnetic beads connected to a human red blood cell will swim when subject to an oscillating magnetic field. Bending waves propagate from the tip of the tail toward the red blood cell in a fashion analogous to flagellum beating, making the artificial swimmer a candidate for studying what has been referred to as micro-swimming. In this study, we demonstrate that under the influence of a rotating field the artificial swimmer will perform -type swimming. We conduct numerical simulations of the swimmer where the paramagnetic tail is represented as a series of rigid spheres connected by flexible but inextensible links. An optimal range of parameters governing the relative strength of viscous, elastic and magnetic forces is identified for swimming speed. A parameterization of the motion is extracted and examined as a function of the driving frequency. With a continuous elastica/resistive force model, we obtain an expression for the swimming speed in the low-frequency limit. Using this expression we explore further the effects of the applied field, the ratio of the transverse field to the constant field, and the ratio of the radius of the sphere to the length of the filament tail on the resulting dynamics.

Characterization of undulatory locomotion in granular media

NASA Astrophysics Data System (ADS)

Peng, Zhiwei; Pak, On Shun; Elfring, Gwynn

2015-11-01

Undulatory locomotion is ubiquitous in nature, from the swimming of flagellated microorganisms in biological fluids, to the slithering of snakes on land, or the locomotion of sandfish lizards in sand. Analysis of locomotion in granular materials is relatively less developed compared with fluids partially due to a lack of validated force models but a recently proposed resistive force theory (RFT) in granular media has been shown useful in studying the locomotion of a sand-swimming lizard. Here we employ this model to investigate the swimming characteristics of an undulating slender filament of both finite and infinite length. For infinite swimmers, similar to results in viscous fluids, the sawtooth waveform is found to be optimal for propulsion speed at a given power consumption. We also compare the swimming characteristics of sinusoidal and sawtooth swimmers with swimming in viscous fluids. More complex swimming dynamics emerge when the assumption of an infinite swimmer is removed. In particular, we characterize the effects of drifting and pitching in terms of propulsion speed and efficiency for a finite sinusoidal swimmer. The results complement our understanding of undulatory locomotion and provide insights into the effective design of locomotive systems in granular media.

Agmatine attenuates chronic unpredictable mild stress induced behavioral alteration in mice.

PubMed

Taksande, Brijesh G; Faldu, Dharmesh S; Dixit, Madhura P; Sakaria, Jay N; Aglawe, Manish M; Umekar, Milind J; Kotagale, Nandkishor R

2013-11-15

Chronic stress exposure and resulting dysregulation of the hypothalamic pituitary adrenal axis develops susceptibility to variety of neurological and psychiatric disorders. Agmatine, a putative neurotransmitter has been reported to be released in response to various stressful stimuli to maintain the homeostasis. Present study investigated the role of agmatine on chronic unpredictable mild stress (CUMS) induced behavioral and biochemical alteration in mice. Exposure of mice to CUMS protocol for 28 days resulted in diminished performance in sucrose preference test, splash test, forced swim test and marked elevation in plasma corticosterone levels. Chronic agmatine (5 and 10 mg/kg, ip, once daily) treatment started on day-15 and continued till the end of the CUMS protocol significantly increased sucrose preference, improved self-care and motivational behavior in the splash test and decreased duration of immobility in the forced swim test. Agmatine treatment also normalized the elevated corticosterone levels and prevented the body weight changes in chronically stressed animals. The pharmacological effect of agmatine was comparable to selective serotonin reuptake inhibitor, fluoxetine (10mg/kg, ip). Results of present study clearly demonstrated the anti-depressant like effect of agmatine in chronic unpredictable mild stress induced depression in mice. Thus the development of drugs based on brain agmatinergic modulation may represent a new potential approach for the treatment of stress related mood disorders like depression. © 2013 Published by Elsevier B.V.

Is Forced Swimming Immobility a Good Endpoint for Modeling Negative Symptoms of Schizophrenia? - Study of Sub-Anesthetic Ketamine Repeated Administration Effects.

PubMed

Neves, Gilda; Borsoi, Milene; Antonio, Camila B; Pranke, Mariana A; Betti, Andresa H; Rates, Stela M K

2017-01-01

Immobility time in the forced swimming has been described as analogous to emotional blunting or apathy and has been used for characterizing schizophrenia animal models. Several clinical studies support the use of NMDA receptor antagonists to model schizophrenia in rodents. Some works describe the effects of ketamine on immobility behavior but there is variability in the experimental design used leading to controversial results. In this study, we evaluated the effects of repeated administration of ketamine sub-anesthetic doses in forced swimming, locomotion in response to novelty and novel object recognition, aiming a broader evaluation of the usefulness of this experimental approach for modeling schizophrenia in mice. Ketamine (30 mg/kg/day i.p. for 14 days) induced a not persistent decrease in immobility time, detected 24h but not 72h after treatment. This same administration protocol induced a deficit in novel object recognition. No change was observed in mice locomotion. Our results confirm that repeated administration of sub-anesthetic doses of ketamine is useful in modeling schizophrenia-related behavioral changes in mice. However, the immobility time during forced swimming does not seem to be a good endpoint to evaluate the modeling of negative symptoms in NMDAR antagonist animal models of schizophrenia.

7. Credit USAF, ca. 1952. Original housed in the Photograph ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. Credit USAF, ca. 1952. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. Oblique aerial view of North Base AFFTC (Air Force Flight Test Center) looking west northwest. The flight line at the edge of Rogers Dry Lake appears in the foreground, served by the facility's four hangars. Temporary structures beyond the hangars were demolished later in the 1950s. The fence that formerly surrounded the swimming pool in earlier photos has been taken down. In the distance lies the Jet Propulsion Laboratory Edwards Test Station, in its pre-1953 configuration. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

Opioid/NMDA receptors blockade reverses the depressant-like behavior of foot shock stress in the mouse forced swimming test.

PubMed

Haj-Mirzaian, Arya; Ostadhadi, Sattar; Kordjazy, Nastaran; Dehpour, Ahmad Reza; Ejtemaei Mehr, Shahram

2014-07-15

Opioid and glutamatergic receptors have a key role in depression following stress. In this study, we assessed opioid and glutamatergic receptors interaction with the depressant-like behavior of acute foot-shock stress in the mouse forced swimming test. Stress was induced by intermittent foot shock stimulation during 30min and swim periods were afterwards conducted by placing mice in separated glass cylinders filled with water for 6min. The immobility time during the last 4min of the test was considered. Acute foot-shock stress significantly increased the immobility time of mice compared to non-stressed control group (P≤0.01). Administration of non-selective opioid receptors antagonist, naltrexone (1 and 2mg/kg, i.p.), and the selective non-competitive NMDA receptor antagonist, MK-801 (0.05mg/kg, i.p.), and the selective serotonin reuptake inhibitor, fluoxetine (5mg/kg), significantly reduced the immobility time in stressed animals (P≤0.01). Lower doses of MK-801 (0.01mg/kg), naltrexone (0.3mg/kg), NMDA (75mg/kg) and morphine(5mg/kg) had no effect on foot-shock stressed mice. Combined treatment of sub-effective doses of naltrexone and MK-801 significantly showed an antidepressant-like effect (P≤0.001). On the other hand, co-administration of non-effective doses of NMDA and morphine with effective doses of naltrexone and MK-801 reversed the anti-immobility effect of these drugs. Taken together, we have for the first time demonstrated the possible role of opioid/NMDA receptors signaling in the depressant-like effect of foot-shock stress, and proposed the use of drugs that act like standard anti-depressants in stress-induced depression. Copyright © 2014. Published by Elsevier B.V.

Daily maternal separations during stress hyporesponsive period decrease the thresholds of panic-like behaviors to electrical stimulation of the dorsal periaqueductal gray of the adult rat.

PubMed

Borges-Aguiar, Ana Cristina; Schauffer, Luana Zanoni; de Kloet, Edo Ronald; Schenberg, Luiz Carlos

2018-05-15

The present study examined whether early life maternal separation (MS), a model of childhood separation anxiety, predisposes to panic at adulthood. For this purpose, male pups were submitted to 3-h daily maternal separations along postnatal (PN) days of either the 'stress hyporesponsive period' (SHRP) from PN4 to PN14 (MS11) or throughout lactation from PN2 to PN21 (MS20). Pups were further reunited to conscious (CM) or anesthetized (AM) mothers to assess the effect of mother-pup interaction upon reunion. Controls were subjected to brief handling (15 s) once a day throughout lactation (BH20). As adults (PN60), rats were tested for the thresholds to evoke panic-like behaviors upon electrical stimulation of dorsal periaqueductal gray matter and exposed to an elevated plus-maze, an open-field, a forced swim and a sucrose preference test. A factor analysis was also performed to gain insight into the meaning of behavioral tests. MS11-CM rather than MS20-CM rats showed enhanced panic responses and reductions in both swimming and sucrose preference. Panic facilitations were less intense in mother-neglected rats. Although MS did not affect anxiety, MS11-AM showed robust reductions of defecation in an open-field. Factor analysis singled out anxiety, hedonia, exploration, coping and gut activity. Although sucrose preference and coping loaded on separate factors, appetite (adult weight) correlated with active coping in both forced swim and open-field (central area exploration). Concluding, whereas 3h-daily maternal separations during SHRP increased rat's susceptibility to experimental panic attacks, separations throughout lactation had no effects on panic and enhanced active coping. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of hydrodynamic interactions in bacterial swimming.

NASA Astrophysics Data System (ADS)

Chattopadhyay, Suddhashil; Lun Wu, Xiao

2008-03-01

The lack of precise experimental data has prevented the investigation of the effects of long range hydrodynamic interactions in bacterial swimming. We perform measurements on various strains of bacteria with the aid of optical tweezers to shed light on this aspect of bacterial motility. Geometrical parameters recorded by fluorescence microscopy are used with theories which model flagella propulsion (Resistive force theory & Lighthill's formulation which includes long range interactions). Comparison of the predictions of these theories with experimental data, observed directly from swimming bacterium, led to the conclusion that while long range inetractions were important for single polar flagellated strains (Vibrio Alginolyticus & Caulobacter Crescentus), local force theory was adequate to describe the swimming of multi-flagellated Esherichia Coli. We performed additional measurements on E. Coli minicells (miniature cells with single polar flagellum) to try and determine the cause of this apparent effect of shielding of long range interactions in multiple flagellated bacteria.

Depressive disorder and gastrointestinal dysfunction after myocardial infarct are associated with abnormal tryptophan-5-hydroxytryptamine metabolism in rats

PubMed Central

Liu, Chunyan; Wang, Yangang

2017-01-01

In this study, we investigated the relationship between tryptophan-5-hydroxytryptamine metabolism, depressive disorder, and gastrointestinal dysfunction in rats after myocardial infarction. Our goal was to elucidate the physiopathologic bases of somatic/psychiatric depression symptoms after myocardial infarction. A myocardial infarction model was established by permanent occlusion of the left anterior descending coronary artery. Depression-like behavior was evaluated using the sucrose preference test, open field test, and forced swim test. Gastric retention and intestinal transit were detected using the carbon powder labeling method. Immunohistochemical staining was used to detect indoleamine 2,3-dioxygenase expression in the hippocampus and ileum. High-performance liquid chromatography with fluorescence and ultraviolet detection determined the levels of 5-hydroxytryptamine, its precursor tryptophan, and its metabolite 5-hydroxyindoleacetic acid in the hippocampus, distal ileum, and peripheral blood. All data were analyzed using one-way analyses of variance. Three weeks after arterial occlusion, rats in the model group began to exhibit depression-like symptoms. For example, the rate of sucrose consumption was reduced, the total and central distance traveled in the open field test were reduced, and immobility time was increased, while swimming, struggling and latency to immobility were decreased in the forced swim test. Moreover, the gastric retention rate and gastrointestinal transit rate were increased in the model group. Expression of indoleamine 2,3-dioxygenase was increased in the hippocampus and ileum, whereas 5-hydroxytryptamine metabolism was decreased, resulting in lower 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels in the hippocampus and higher levels in the ileum. Depressive disorder and gastrointestinal dysfunction after myocardial infarction involve abnormal tryptophan-5-hydroxytryptamine metabolism, which may explain the somatic, cognitive, and psychiatric symptoms of depression commonly observed after myocardial infarction. Peripheral 5-hydroxytryptamine is an important substance in the gut-brain axis, and its abnormal metabolism is a critical finding after myocardial infarct. PMID:28212441

Depressive disorder and gastrointestinal dysfunction after myocardial infarct are associated with abnormal tryptophan-5-hydroxytryptamine metabolism in rats.

PubMed

Lu, Xiaofang; Wang, Yuefen; Liu, Chunyan; Wang, Yangang

2017-01-01

In this study, we investigated the relationship between tryptophan-5-hydroxytryptamine metabolism, depressive disorder, and gastrointestinal dysfunction in rats after myocardial infarction. Our goal was to elucidate the physiopathologic bases of somatic/psychiatric depression symptoms after myocardial infarction. A myocardial infarction model was established by permanent occlusion of the left anterior descending coronary artery. Depression-like behavior was evaluated using the sucrose preference test, open field test, and forced swim test. Gastric retention and intestinal transit were detected using the carbon powder labeling method. Immunohistochemical staining was used to detect indoleamine 2,3-dioxygenase expression in the hippocampus and ileum. High-performance liquid chromatography with fluorescence and ultraviolet detection determined the levels of 5-hydroxytryptamine, its precursor tryptophan, and its metabolite 5-hydroxyindoleacetic acid in the hippocampus, distal ileum, and peripheral blood. All data were analyzed using one-way analyses of variance. Three weeks after arterial occlusion, rats in the model group began to exhibit depression-like symptoms. For example, the rate of sucrose consumption was reduced, the total and central distance traveled in the open field test were reduced, and immobility time was increased, while swimming, struggling and latency to immobility were decreased in the forced swim test. Moreover, the gastric retention rate and gastrointestinal transit rate were increased in the model group. Expression of indoleamine 2,3-dioxygenase was increased in the hippocampus and ileum, whereas 5-hydroxytryptamine metabolism was decreased, resulting in lower 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels in the hippocampus and higher levels in the ileum. Depressive disorder and gastrointestinal dysfunction after myocardial infarction involve abnormal tryptophan-5-hydroxytryptamine metabolism, which may explain the somatic, cognitive, and psychiatric symptoms of depression commonly observed after myocardial infarction. Peripheral 5-hydroxytryptamine is an important substance in the gut-brain axis, and its abnormal metabolism is a critical finding after myocardial infarct.

Clinical doses of citalopram or reboxetine differentially modulate passive and active behaviors of female Wistar rats with high or low immobility time in the forced swimming test.

PubMed

Flores-Serrano, Ana Gisela; Vila-Luna, María Leonor; Álvarez-Cervera, Fernando José; Heredia-López, Francisco José; Góngora-Alfaro, José Luis; Pineda, Juan Carlos

2013-09-01

The sensitivity of immobility time (IT) to antidepressant-drugs differs in rats expressing high or low motor activity during the forced swimming test (FST). However, whether this heterogeneity is expressed after the administration of the most selective serotonin and norepinephrine reuptake inhibitors (SSRIs and SNRIs, respectively) is unknown. We compared the influence of either the SSRI citalopram or the SNRI reboxetine with the tricyclic antidepressant amitriptyline on two subgroups of female Wistar rats expressing high IT (HI; at or above the mean value) or low IT (LI; below the mean) during the initial 5 min of the first session of the FST. None of the tested drugs increased motor activity in the open field test. When vehicle was applied to either HI or LI rats, IT increased in the second session of the FST. This increment concurred with a simultaneous climbing time (CT) decrement. When amitriptyline (15 mg/kg) was tested the CT increased for both HI and LI rats. This increment was accompanied by an IT decrement in HI and LI rats. Reboxetine (0.16 or 1 mg/kg) precluded IT and CT changes in both HI and LI rats and produced a swimming time reduction. Citalopram (0.4, 1, and 3 mg/kg) essentially mimicked the influence of reboxetine on the IT and CT in LI rats, as well as in HI rats, but in the latter case only at 3 mg/kg. Yet, at the dose of 10 mg/kg citalopram lacked this effect in both subgroups. No differences were detected when the IT of LI rats was evaluated with citalopram (3 mg/kg) during estrus or diestrus stage. These results show that clinical doses of citalopram produced an antidepressant-like effect selectively in LI rats, while amitriptyline or reboxetine produced this effect in both LI and HI animals. Copyright © 2013 Elsevier Inc. All rights reserved.

Age-related changes in the antidepressant-like effect of desipramine and fluoxetine in the rat forced-swim test.

PubMed

Olivares-Nazario, Maribel; Fernández-Guasti, Alonso; Martínez-Mota, Lucía

2016-02-01

Some reports suggest that older patients are less responsive to antidepressants than young adults, but this idea has not been fully supported. Here, we investigated the role of aging in the behavioral effects of the antidepressants, desipramine (DMI) (5, 10, and 20 mg/kg) and fluoxetine (FLX) (5, 10, and 20 mg/kg) in young adults (3-5 months), middle-aged (MA, 12-15 months), and senescent (SE, 23-25 months) male rats in the forced-swim test. In addition, locomotor activity and motor coordination were assessed as side-effects. DMI and fluoxetine produced an antidepressant-like effect in YA and MA animals, although in the latter group, a shift to the right in the dose-response curve was found for DMI. Importantly, neither drug was effective in SE animals. Motor side-effects were produced mainly by DMI in MA and SE rats. Therefore, a decrease in the antidepressant-like effect is associated strongly with senescence as well as an increased vulnerability to motor side-effects, particularly of tricyclics. This study is significant because SE animals are scarcely studied in pharmacological screening tests, and our findings might be useful for improving antidepressant treatments for the increasing aged population.

Neuronal NOS inhibitor 1-(2-trifluoromethylphenyl)-imidazole augment the effects of antidepressants acting via serotonergic system in the forced swimming test in rats.

PubMed

Ulak, Güner; Mutlu, Oguz; Akar, Füruzan Yildiz; Komsuoğlu, F Ipek; Tanyeri, Pelin; Erden, B Faruk

2008-10-01

Treatment-resistant depression has necessitated new therapeutic strategies in augmenting the therapeutic actions of currently existing antidepressant drugs. The aim of this study was to investigate the possibility of synergistic interaction between 1-(2-trifluoromethylphenyl)-imidazole (TRIM), a novel neuronal nitric oxide synthase (nNOS) inhibitor and conventional antidepressants of different classes in the forced swimming test (FST) in rats. TRIM decreased the immobility time at 50 mg/kg doses in the FST in rats. Treatment with a behaviourally subeffective dose of TRIM (20 mg/kg) augmented the behavioural effect of tricyclic antidepressant imipramine, selective serotonin re-uptake inhibitor (SSRI) citalopram and fluoxetine or selective serotonin reuptake enhancer tianeptine but failed to augment the antidepressant effect of reboxetine, a noradrenaline re-uptake inhibitor, in this test. Therefore inhibition of NOS augments the effects of antidepressants acting on serotonergic system in the FST. Neither TRIM (10-50 mg/kg) nor other drug treatments affected the locomotor activity of animals. These findings are in agreement with the view that antidepressant effects or augmentation of these effects in the FST may be explained with inhibition of NOS activity and this may be a new approach in offering greater therapeutic efficacy of antidepressants acting via serotonergic system.

Neurobehavioral and Antioxidant Effects of Ethanolic Extract of Yellow Propolis

PubMed Central

da Silveira, Cinthia Cristina Sousa de Menezes; Fernandes, Luanna Melo Pereira; Silva, Mallone Lopes; Luz, Diandra Araújo; Gomes, Antônio Rafael Quadros; Machado, Christiane Schineider; de Lira, Tatiana Onofre; Ferreira, Antonio Gilberto

2016-01-01

Propolis is a resin produced by bees from raw material collected from plants, salivary secretions, and beeswax. New therapeutic properties for the Central Nervous System have emerged. We explored the neurobehavioral and antioxidant effects of an ethanolic extract of yellow propolis (EEYP) rich in triterpenoids, primarily lupeol and β-amyrin. Male Wistar rats, 3 months old, were intraperitoneally treated with Tween 5% (control), EEYP (1, 3, 10, and 30 mg/kg), or diazepam, fluoxetine, and caffeine (positive controls) 30 min before the assays. Animals were submitted to open field, elevated plus maze, forced swimming, and inhibitory avoidance tests. After behavioral tasks, blood samples were collected through intracardiac pathway, to evaluate the oxidative balance. The results obtained in the open field and in the elevated plus maze assay showed spontaneous locomotion preserved and anxiolytic-like activity. In the forced swimming test, EEYP demonstrated antidepressant-like activity. In the inhibitory avoidance test, EEYP showed mnemonic activity at 30 mg/kg. In the evaluation of oxidative biochemistry, the extract reduced the production of nitric oxide and malondialdehyde without changing level of total antioxidant, catalase, and superoxide dismutase, induced by behavioral stress. Our results highlight that EEYP emerges as a promising anxiolytic, antidepressant, mnemonic, and antioxidant natural product. PMID:27822336

Young-Adult Male Rats' Vulnerability to Chronic Mild Stress Is Reflected by Anxious-Like instead of Depressive-Like Behaviors.

PubMed

José Jaime, Herrera-Pérez; Venus, Benítez-Coronel; Graciela, Jiménez-Rubio; Tania, Hernández-Hernández Olivia; Lucía, Martínez-Mota

2016-01-01

In a previous study, we found that chronic mild stress (CMS) paradigm did not induce anhedonia in young-adult male rats but it reduced their body weight gain. These contrasting results encouraged us to explore other indicators of animal's vulnerability to stress such as anxious-like behaviors, since stress is an etiologic factor also for anxiety. Thus, in this study, we evaluated the vulnerability of these animals to CMS using behavioral tests of depression or anxiety and measuring serum corticosterone. Male Wistar rats were exposed to four weeks of CMS; the animals' body weight and sucrose preference (indicator of anhedonia) were assessed after three weeks, and, after the fourth week, some animals were evaluated in a behavioral battery (elevated plus maze, defensive burying behavior, and forced swimming tests); meanwhile, others were used to measure serum corticosterone. We found that CMS (1) did not affect sucrose preference, immobility behavior in the forced swimming test, or serum corticosterone; (2) decreased body weight gain; and (3) increased the rat's entries into closed arms of the plus maze and the cumulative burying behavior. These data indicate that young male rats' vulnerability to CMS is reflected as poor body weight gain and anxious-like instead of depressive-like behaviors.

Young-Adult Male Rats' Vulnerability to Chronic Mild Stress Is Reflected by Anxious-Like instead of Depressive-Like Behaviors

PubMed Central

José Jaime, Herrera-Pérez; Venus, Benítez-Coronel; Graciela, Jiménez-Rubio; Tania, Hernández-Hernández Olivia

2016-01-01

In a previous study, we found that chronic mild stress (CMS) paradigm did not induce anhedonia in young-adult male rats but it reduced their body weight gain. These contrasting results encouraged us to explore other indicators of animal's vulnerability to stress such as anxious-like behaviors, since stress is an etiologic factor also for anxiety. Thus, in this study, we evaluated the vulnerability of these animals to CMS using behavioral tests of depression or anxiety and measuring serum corticosterone. Male Wistar rats were exposed to four weeks of CMS; the animals' body weight and sucrose preference (indicator of anhedonia) were assessed after three weeks, and, after the fourth week, some animals were evaluated in a behavioral battery (elevated plus maze, defensive burying behavior, and forced swimming tests); meanwhile, others were used to measure serum corticosterone. We found that CMS (1) did not affect sucrose preference, immobility behavior in the forced swimming test, or serum corticosterone; (2) decreased body weight gain; and (3) increased the rat's entries into closed arms of the plus maze and the cumulative burying behavior. These data indicate that young male rats' vulnerability to CMS is reflected as poor body weight gain and anxious-like instead of depressive-like behaviors. PMID:27433469

Antidepressant-Like Effect of Isorhynchophylline in Mice.

PubMed

Xian, Yan-Fang; Fan, Ding; Ip, Siu-Po; Mao, Qing-Qiu; Lin, Zhi-Xiu

2017-02-01

Isorhynchophylline (IRN), an oxindole alkaloid, has been identified as the main active ingredient responsible for the biological activities of Uncaria rhynchophylla (Miq) Miq ex Havil. (Rubiaceae). Previous studies in our laboratory have revealed that IRN possesses potent neuroprotective effects in different models of Alzheimer's disease. However, the antidepressant-like effects of IRN are remained unclear. The present study aims to evaluate the antidepressant-like effects of IRN. The antidepressant-like effects of IRN was determined by using animal models of depression including forced swimming and tail suspension tests. The acting mechanism was explored by determining the effect of IRN on the levels of monoamine neurotransmitters and the activities of monoamine oxidases. Intragastric administration of IRN at 10, 20 and 40 mg/kg for 7 days caused a significant reduction of immobility time in both forced swimming and tail suspension tests, while IRN did not stimulate locomotor activity in the open-field test. In addition, IRN treatment antagonized reserpine-induced ptosis and significantly enhanced the levels of monoamine neurotransmitters including norepinephrine (NE) and 5-hydroxytryptamine (5-HT), and the activity of monoamine oxidase A (MAO-A) in the hippocampus and frontal cortex of mice. These results suggest that the antidepressant-like effects of IRN are mediated, at least in part, by the inhibition of monoamine oxidases.

How body torque and Strouhal number change with swimming speed and developmental stage in larval zebrafish.

PubMed

van Leeuwen, Johan L; Voesenek, Cees J; Müller, Ulrike K

2015-09-06

Small undulatory swimmers such as larval zebrafish experience both inertial and viscous forces, the relative importance of which is indicated by the Reynolds number (Re). Re is proportional to swimming speed (vswim) and body length; faster swimming reduces the relative effect of viscous forces. Compared with adults, larval fish experience relatively high (mainly viscous) drag during cyclic swimming. To enhance thrust to an equally high level, they must employ a high product of tail-beat frequency and (peak-to-peak) amplitude fAtail, resulting in a relatively high fAtail/vswim ratio (Strouhal number, St), and implying relatively high lateral momentum shedding and low propulsive efficiency. Using kinematic and inverse-dynamics analyses, we studied cyclic swimming of larval zebrafish aged 2-5 days post-fertilization (dpf). Larvae at 4-5 dpf reach higher f (95 Hz) and Atail (2.4 mm) than at 2 dpf (80 Hz, 1.8 mm), increasing swimming speed and Re, indicating increasing muscle powers. As Re increases (60 → 1400), St (2.5 → 0.72) decreases nonlinearly towards values of large swimmers (0.2-0.6), indicating increased propulsive efficiency with vswim and age. Swimming at high St is associated with high-amplitude body torques and rotations. Low propulsive efficiencies and large yawing amplitudes are unavoidable physical constraints for small undulatory swimmers. © 2015 The Author(s).

How body torque and Strouhal number change with swimming speed and developmental stage in larval zebrafish

PubMed Central

van Leeuwen, Johan L.; Voesenek, Cees J.; Müller, Ulrike K.

2015-01-01

Small undulatory swimmers such as larval zebrafish experience both inertial and viscous forces, the relative importance of which is indicated by the Reynolds number (Re). Re is proportional to swimming speed (vswim) and body length; faster swimming reduces the relative effect of viscous forces. Compared with adults, larval fish experience relatively high (mainly viscous) drag during cyclic swimming. To enhance thrust to an equally high level, they must employ a high product of tail-beat frequency and (peak-to-peak) amplitude fAtail, resulting in a relatively high fAtail/vswim ratio (Strouhal number, St), and implying relatively high lateral momentum shedding and low propulsive efficiency. Using kinematic and inverse-dynamics analyses, we studied cyclic swimming of larval zebrafish aged 2–5 days post-fertilization (dpf). Larvae at 4–5 dpf reach higher f (95 Hz) and Atail (2.4 mm) than at 2 dpf (80 Hz, 1.8 mm), increasing swimming speed and Re, indicating increasing muscle powers. As Re increases (60 → 1400), St (2.5 → 0.72) decreases nonlinearly towards values of large swimmers (0.2–0.6), indicating increased propulsive efficiency with vswim and age. Swimming at high St is associated with high-amplitude body torques and rotations. Low propulsive efficiencies and large yawing amplitudes are unavoidable physical constraints for small undulatory swimmers. PMID:26269230

Stress response of lead-exposed rainbow trout (Oncorhynchus mykiss) during swimming performance and hypoxia challenges

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

Phillips, K.A.; Caldwell, C.A.; Sandheinrich, M.B.

1995-12-31

Contaminants often invoke a stress response in aquatic organisms, and may compromise their capacity to respond to secondary stressors. This may reduce growth, reproduction and survival. The authors objectives were to assess the effects of lead and secondary stressors on hematology and blood chemistry of rainbow trout. After a 7 to 8-week aqueous exposure to Pb(100{micro}g/L), rainbow trout were challenged with forced swimming or hypoxia. Lead significantly reduced concentrations of 5-aminolevulinic acid dehydratase (ALAD), but not other constituents in the blood. Lead did not affect the swimming endurance of the fish. Hematocrit, mean cell hemoglobin content, and mean cell volumemore » were significantly lower in Pb-exposed trout following the swimming challenge. Although hypoxia resulted in increased hematocrit and plasma glucose concentrations, there were no significant differences between the Pb and control groups. Hypoxia did not affect plasma chloride concentrations, although concentrations increased in Pb-exposed trout. There was no difference in lactic acid concentrations between Pb-exposed and control fish after forced swimming or hypoxia.« less

Numerical and experimental investigations of human swimming motions

PubMed Central

Takagi, Hideki; Nakashima, Motomu; Sato, Yohei; Matsuuchi, Kazuo; Sanders, Ross H.

2016-01-01

ABSTRACT This paper reviews unsteady flow conditions in human swimming and identifies the limitations and future potential of the current methods of analysing unsteady flow. The capability of computational fluid dynamics (CFD) has been extended from approaches assuming steady-state conditions to consideration of unsteady/transient conditions associated with the body motion of a swimmer. However, to predict hydrodynamic forces and the swimmer’s potential speeds accurately, more robust and efficient numerical methods are necessary, coupled with validation procedures, requiring detailed experimental data reflecting local flow. Experimental data obtained by particle image velocimetry (PIV) in this area are limited, because at present observations are restricted to a two-dimensional 1.0 m2 area, though this could be improved if the output range of the associated laser sheet increased. Simulations of human swimming are expected to improve competitive swimming, and our review has identified two important advances relating to understanding the flow conditions affecting performance in front crawl swimming: one is a mechanism for generating unsteady fluid forces, and the other is a theory relating to increased speed and efficiency. PMID:26699925

Numerical and experimental investigations of human swimming motions.

PubMed

Takagi, Hideki; Nakashima, Motomu; Sato, Yohei; Matsuuchi, Kazuo; Sanders, Ross H

2016-08-01

This paper reviews unsteady flow conditions in human swimming and identifies the limitations and future potential of the current methods of analysing unsteady flow. The capability of computational fluid dynamics (CFD) has been extended from approaches assuming steady-state conditions to consideration of unsteady/transient conditions associated with the body motion of a swimmer. However, to predict hydrodynamic forces and the swimmer's potential speeds accurately, more robust and efficient numerical methods are necessary, coupled with validation procedures, requiring detailed experimental data reflecting local flow. Experimental data obtained by particle image velocimetry (PIV) in this area are limited, because at present observations are restricted to a two-dimensional 1.0 m(2) area, though this could be improved if the output range of the associated laser sheet increased. Simulations of human swimming are expected to improve competitive swimming, and our review has identified two important advances relating to understanding the flow conditions affecting performance in front crawl swimming: one is a mechanism for generating unsteady fluid forces, and the other is a theory relating to increased speed and efficiency.

Prophylactic effects of swimming exercise on autophagy-induced muscle atrophy in diabetic rats

PubMed Central

Lee, Youngjeon; Kim, Joo-Heon; Hong, Yunkyung; Lee, Sang-Rae; Chang, Kyu-Tae

2012-01-01

Diabetes decreases skeletal muscle mass and induces atrophy. However, the mechanisms by which hyperglycemia and insulin deficiency modify muscle mass are not well defined. In this study, we evaluated the effects of swimming exercise on muscle mass and intracellular protein degradation in diabetic rats, and proposed that autophagy inhibition induced by swimming exercise serves as a hypercatabolic mechanism in the skeletal muscles of diabetic rats, supporting a notion that swimming exercise could efficiently reverse the reduced skeletal muscle mass caused by diabetes. Adult male Sprague-Dawley rats were injected intraperitoneally with streptozotocin (60 mg/kg body weight) to induce diabetes and then submitted to 1 hr per day of forced swimming exercise, 5 days per week for 4 weeks. We conducted an intraperitoneal glucose tolerance test on the animals and measured body weight, skeletal muscle mass, and protein degradation and examined the level of autophagy in the isolated extensor digitorum longus, plantaris, and soleus muscles. Body weight and muscle tissue mass were higher in the exercising diabetic rats than in control diabetic rats that remained sedentary. Compared to control rats, exercising diabetic rats had lower blood glucose levels, increased intracellular contractile protein expression, and decreased autophagic protein expression. We conclude that swimming exercise improves muscle mass in diabetes-induced skeletal muscle atrophy, suggesting the activation of autophagy in diabetes contributes to muscle atrophy through hypercatabolic metabolism and that aerobic exercise, by suppressing autophagy, may modify or reverse skeletal muscle wasting in diabetic patients. PMID:23091517

[Effect of Acupuncture Intervention on c-jun N-terminal Kinase Signaling in the Hippocampus in Rats with Forced Swimming Stress].

PubMed

Guo, Yu; Xu, Ke; Bao, Wu-ye; Wang, Yu; Zhang, Xu-hui; Xu, Ming-min; Yu, Miao; Zhang, Chun-tao; Zhao, Bing-cong; Wu, Ji-hong; Tu, Ya

2016-02-01

To observe the effect of acupuncture on c-jun N-terminal Kinase (JNK) signaling in the hippocampus in rats with forced-swimming stress, so as to reveal its underlying mechanism in relieving depression-like motor response. Forty-eight Sprague-Dawley rats were randomly divided into 8 groups as control, control + JNK inhibitor (SP 600125) , model, model + SP 600125, acupuncture, acupuncture + SP 600125, Fluoxetine (an anti-depressant) , and Fluoxetine + SP 600125 (n = 6 in each group). The depression-like behavior (immobility) model was established by forcing the rat to swim in a glass-cylinder and solitary raise. Acupuncture stimulation was applied to "Baihui" (GV-20) and "Yintang" (GV 29) for 20 min before forced swimming and once again 24 h later.. The rats of the Fluoxetine and Fluoxetine+ SP 600125 groups were treated by intragastric administration of fluoxetine 10 mL (1.8 mg)/kg before forced swimming and once again 24 h thereafter. The rats of the model + SP 600125 and acupuncture + SP 600125 groups were treated by intraperitoneal injection of SP 600125 (10 mg/kg) 90 min before forced swimming and 30 min before acupuncture intervention, respectively. The immobility duration of rats in the water glass-cylinder was used to assess their depression-like behavior response. The expression levels of protein kinase kinase 4 (MKK 4), MKK 7, JNK, and phosphorylated JNK (p-JNK) in the hippocampus were detected by Western blot. Compared to the control group, the duration of immobility, and the expression levels of hippocampal MKK 4, MKK 7, and p-JNK proteins were significantly increased in the model group (P < 0.01). While in comparison with the model group, the duration of immobility in the model + SP 600125, acupuncture, acupuncture + SP 600125, Fluoxetine and Fluoxetine + SP 600125 groups, the expression levels of hippocampal MKK 4 and MKK 7 proteins in the Fluoxetine + SP 600125 group, and those of p-JNK protein in the acupuncture, acupuncture + SP 600125, model + SP 600125, Fluoxetine and Fluoxetine + SP 600125 groups were considerably decreased (P < 0.05, P < 0.01). No significant differences were found between the control and control + SP 600125 groups and among the model + SP 600125, acupuncture, acupuncture + SP 600125, Fluoxetine and Fluoxetine + SP 600125 groups in the duration of immobility (P > 0.05), and in the expression level of p-JNK protein (P > 0.05). No significant changes were found in the expression levels of JNK among the 8 groups (P > 0.05). Acupuncture stimulation of GV 20 and GV 29 is effective in relieving depression-like motor response in forced-swimming stress rats, which may be closely associated with its effects in down-regulating the expression of hippocampal p-JNK protein.

Effect of gamma irradiation on phenol content, antioxidant activity and biological activity of black maca and red maca extracts (Lepidium meyenii walp).

PubMed

Zevallos-Concha, A; Nuñez, D; Gasco, M; Vasquez, C; Quispe, M; Gonzales, G F

2016-01-01

This study was performed to determine the effects of gamma irradiation on UV spectrum on maca, total content of polyphenols, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities and in vivo biological activities of red and black maca extracts (Lepidium meyenii). Adult mice of the strain Swiss aged 3 months and weighing 30-35 g in average were used to determine biological activities. Daily sperm production, effect on testosterone-induced prostate hyperplasia and forced swimming test were used to determine the effect of irradiation on biological activities of maca extracts. Irradiation did not show differences in UV spectrum but improves the amount of total polyphenols in red maca as well as in black maca extracts. In both cases, black maca extract has more content of polyphenols than red maca extract (p < 0.01). Gamma irradiation significantly increased the antioxidant capacity (p < 0.05). No difference was observed in daily sperm production when irradiated and nonirradiated maca extract were administered to mice (p > 0.05). Black maca extract but not red maca extract has more swimming endurance capacity in the forced swimming test. Irradiation of black maca extract increased the swimming time to exhaustion (p < 0.05). This is not observed with red maca extract (p > 0.05). Testosterone enanthate (TE) increased significantly the ventral prostate weight. Administration of red maca extract in animals treated with TE prevented the increase in prostate weight. Irradiation did not modify effect of red maca extract on prostate weight (p > 0.05). In conclusion, irradiation does not alter the biological activities of both black maca and red maca extracts. It prevents the presence of microorganisms in the extracts of black or red maca, but the biological activities were maintained.

Hydrogen Water Drinking Exerts Antifatigue Effects in Chronic Forced Swimming Mice via Antioxidative and Anti-Inflammatory Activities

PubMed Central

Ara, Jesmin; Lee, Sung Pyo; Jung, Jin Young

2018-01-01

Purpose This study was performed to evaluate antifatigue effect of hydrogen water (HW) drinking in chronic forced exercise mice model. Materials and Methods Twelve-week-old C57BL6 female mice were divided into nonstressed normal control (NC) group and stressed group: (purified water/PW-treated group and HW-treated group). Stressed groups were supplied with PW and HW, respectively, ad libitum and forced to swim for the stress induction every day for 4 consecutive weeks. Gross antifatigue effects of HW were assessed by swimming endurance capacity (once weekly for 4 wk), metabolic activities, and immune-redox activities. Metabolic activities such as blood glucose, lactate, glycogen, blood urea nitrogen (BUN), and lactate dehydrogenase (LDH) as well as immune-redox activities such as reactive oxygen species (ROS), nitric oxide (NO), glutathione peroxidase (GPx), catalase, and the related cytokines were evaluated to elucidate underlying mechanism. Blood glucose and lactate were measured at 0 wk (before swimming) and 4 wk (after swimming). Results HW group showed a higher swimming endurance capacity (p < 0.001) than NC and PW groups. Positive metabolic effects in HW group were revealed by the significant reduction of blood glucose, lactate, and BUN in serum after 4 wk (p < 0.01, resp.), as well as the significant increase of liver glycogen (p < 0.001) and serum LDH (p < 0.05) than PW group. In parallel, redox balance was represented by lower NO in serum (p < 0.01) and increased level of GPx in both serum and liver (p < 0.05) than PW group. In line, the decreased levels of serum TNF-α (p < 0.01), IL-6, IL-17, and liver IL-1β (p < 0.05) in HW group revealed positive cytokine profile compared to PW and NC group. Conclusion This study shows antifatigue effects of HW drinking in chronic forced swimming mice via metabolic coordination and immune-redox balance. In that context, drinking HW could be applied to the alternative and safety fluid remedy for chronic fatigue control. PMID:29850492

Swim Test Requirements at Four-Year Universities in the United States.

ERIC Educational Resources Information Center

Ormond, Frank; And Others

1997-01-01

Surveys of 331 four-year universities nationwide examined swim test requirements and reasons for administering or not administering swim tests. Responses from 331 returned questionnaires indicated that 5% of the schools had swim test requirements, though 25% had them previously. Lack of a physical education requirement was the most commonly cited…

Chronic Desipramine Treatment Rescues Depression-Related, Social and Cognitive Deficits in Engrailed-2 Knockout Mice

PubMed Central

Brielmaier, Jennifer; Senerth, Julia M.; Silverman, Jill L.; Matteson, Paul G.; Millonig, James H.; DiCicco-Bloom, Emanuel; Crawley, Jacqueline N.

2014-01-01

Engrailed-2 (En2) is a homeobox transcription factor that regulates neurodevelopmental processes including neuronal connectivity and elaboration of monoaminergic neurons in the ventral hindbrain. We previously reported abnormalities in brain noradrenergic concentrations in En2 null mutant mice that were accompanied by increased immobility in the forced swim test, relevant to depression. An EN2 genetic polymorphism has been associated with autism spectrum disorders (ASD), and mice with a deletion in En2 display social abnormalities and cognitive deficits that may be relevant to multiple neuropsychiatric conditions. The present study evaluated the ability of chronic treatment with desipramine (DMI), a selective norepinephrine reuptake inhibitor and classical antidepressant, to reverse behavioral abnormalities in En2 −/− mice. DMI treatment significantly reduced immobility in the tail suspension and forced swim tests, restored sociability in the three-chambered social approach task, and reversed impairments in contextual fear conditioning in En2 −/− mice. Our findings indicate that modulation of brain noradrenergic systems rescues the depression-related phenotype in En2 −/− mice and suggest new roles for norepinephrine in the pathophysiology of the social and cognitive deficits seen in neuropsychiatric disorders such as autism or schizophrenia. PMID:24730055

Antidepressant effects of ginseng total saponins in the forced swimming test and chronic mild stress models of depression.

PubMed

Dang, Haixia; Chen, Ying; Liu, Xinmin; Wang, Qiong; Wang, Liwei; Jia, William; Wang, Yuqing

2009-11-13

Ginseng total saponins (GTS) are the major active components of Panax ginseng C.A. Meyer, which has been used as a popular tonic herb for 2000 years in Far East countries. In the present study, two classic animal models: the forced swimming test (FST) and the chronic mild stress (CMS) model were used to evaluate the antidepressant-like activities of GTS. It was observed that GTS at doses of 50 and 100 mg/kg significantly reduced the immobility time in the FST in mice after 7-day treatment. GTS also reversed the reduction in the sucrose preference index, decrease in locomotor activity as well as prolongation of latency of feeding in the novelty environment displayed by CMS rats. In addition, HPLC-ECD and immunohistochemical staining analysis indicated that the CMS-induced decrease in monoamine neurotransmitter concentration and brain-derived neurotrophic factor (BDNF) expression in the hippocampus were almost completely reversed by GTS. In conclusion, GTS exerts antidepressant-like effects in two highly specific and predictive animal models of depression. The activity of GTS in antidepression may be mediated partly through enhancing the monoamine neurotransmitter concentration and BDNF expression in the hippocampus.

Effects of palmitoylethanolamide and luteolin in an animal model of anxiety/depression.

PubMed

Crupi, Rosalia; Paterniti, Irene; Ahmad, Akbar; Campolo, Michela; Esposito, Emanuela; Cuzzocrea, Salvatore

2013-11-01

The antidepressant effect of a compound formed by co-ultramicronized palmitoylethanolamide (PEA) and luteolin (PEA+luteolin) was investigated in a mouse model of anxiety/depressive-like behavior. 129Sv/Ev mice were subjected to 6 weeks of corticosterone administration, and then behavior, neurogenesis, neuroplasticity, neurotrophic and apoptotic proteins expression were evaluated. The effect of PEA+luteolin compound treatment (1mg/kg, i.p.), on depression-like behaviour was assessed using different paradigms such as open field, novelty suppressed feeding, forced swim test and elevated plus maze. In particular in the open field, novelty suppressed feeding and elevated plus maze the time spent in the open arm was employed as an indicator of anxiety; forced swim test was used to evaluate the antidepressant capacity of PEA+luteolin on immobility time as an indicator of depression. Adult hippocampal neurogenesis and neuroplasticity were evaluated by immunohistochemical techniques; brain-derived neurotrophic factor and apoptotic protein (Bax and Bcl2) expression were studied by immunostaining and Western blot analysis. For the first time we demonstrated that PEA+luteolin compound exerts a significant antidepressant effect a low dose and may be considered as a novel therapeutic strategy in depression.

Detecting the gravitational sensitivity of Paramecium caudatum using magnetic forces

NASA Astrophysics Data System (ADS)

Guevorkian, Karine; Valles, James M., Jr.

2006-03-01

Under normal conditions, Paramecium cells regulate their swimming speed in response to the pN level mechanical force of gravity. This regulation, known as gravikinesis, is more pronounced when the external force is increased by methods such as centrifugation. Here we present a novel technique that simulates gravity fields using the interactions between strong inhomogeneous magnetic fields and cells. We are able to achieve variable gravities spanning from 10xg to -8xg; where g is earth's gravity. Our experiments show that the swimming speed regulation of Paramecium caudatum to magnetically simulated gravity is a true physiological response. In addition, they reveal a maximum propulsion force for paramecia. This advance establishes a general technique for applying continuously variable forces to cells or cell populations suitable for exploring their force transduction mechanisms.

Improving Attachments of Non-Invasive (Type III) Electronic Data Loggers to Cetaceans

DTIC Science & Technology

2015-09-30

animals in human care will be performed to test and validate this approach. The cadaver trials will enable controlled testing to failure or with both...quantitative metrics and analysis tools to assess the impact of a tag on the animal . Here we will present: 1) the characterization of the mechanical...fine scale motion analysis for swimming animals . 2 APPROACH Our approach is divided into four subtasks: Task 1: Forces and failure modes

Metabolic mapping of the effects of the antidepressant fluoxetine on the brains of congenitally helpless rats.

PubMed

Shumake, Jason; Colorado, Rene A; Barrett, Douglas W; Gonzalez-Lima, F

2010-07-09

Antidepressants require adaptive brain changes before efficacy is achieved, and they may impact the affectively disordered brain differently than the normal brain. We previously demonstrated metabolic disturbances in limbic and cortical regions of the congenitally helpless rat, a model of susceptibility to affective disorder, and we wished to test whether administration of fluoxetine would normalize these metabolic differences. Fluoxetine was chosen because it has become a first-line drug for the treatment of affective disorders. We hypothesized that fluoxetine antidepressant effects may be mediated by decreasing metabolism in the habenula and increasing metabolism in the ventral tegmental area. We measured the effects of fluoxetine on forced swim behavior and regional brain cytochrome oxidase activity in congenitally helpless rats treated for 2 weeks with fluoxetine (5mg/kg, i.p., daily). Fluoxetine reduced immobility in the forced swim test as anticipated, but congenitally helpless rats responded in an atypical manner, i.e., increasing climbing without affecting swimming. As hypothesized, fluoxetine reduced metabolism in the habenula and increased metabolism in the ventral tegmental area. In addition, fluoxetine reduced the metabolism of the hippocampal dentate gyrus and dorsomedial prefrontal cortex. This study provided the first detailed mapping of the regional brain effects of an antidepressant drug in congenitally helpless rats. All of the effects were consistent with previous studies that have metabolically mapped the effects of serotonergic antidepressants in the normal rat brain, and were in the predicted direction of metabolic normalization of the congenitally helpless rat for all affected brain regions except the prefrontal cortex. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Oestrogen-deficient female aromatase knockout (ArKO) mice exhibit depressive-like symptomatology.

PubMed

Dalla, C; Antoniou, K; Papadopoulou-Daifoti, Z; Balthazart, J; Bakker, J

2004-07-01

We recently found that female aromatase knockout (ArKO) mice that are deficient in oestradiol due to a targeted mutation in the aromatase gene show deficits in sexual behaviour that cannot be corrected by adult treatment with oestrogens. We determined here whether these impairments are associated with changes in general levels of activity, anxiety or 'depressive-like' symptomatology due to chronic oestrogen deficiency. We also compared the neurochemical profile of ArKO and wild-type (WT) females, as oestrogens have been shown to modulate dopaminergic, serotonergic and noradrenergic brain activities. ArKO females did not differ from WT in spontaneous motor activity, exploration or anxiety. These findings are in line with the absence of major neurochemical alterations in hypothalamus, prefrontal cortex or striatum, which are involved in the expression of these behaviours. By contrast, ArKO females displayed decreased active behaviours, such as struggling and swimming, and increased passive behaviours, such as floating, in repeated sessions of the forced swim test, indicating that these females exhibit 'depressive-like' symptoms. Adult treatment with oestradiol did not reverse the behavioural deficits observed in the forced swim test, suggesting that they may be due to the absence of oestradiol during development. Accordingly, an increased serotonergic activity was observed in the hippocampus of ArKO females compared with WT, which was also not reversed by adult oestradiol treatment. The possible organizational role of oestradiol on the hippocampal serotonergic system and the 'depressive-like' profile of ArKO females provide new insights into the pathophysiology of depression and the increased vulnerability of women to depression.

Possible involvement of the JAK/STAT signaling pathway in N-acetylcysteine-mediated antidepressant-like effects.

PubMed

Al-Samhari, Marwa M; Al-Rasheed, Nouf M; Al-Rejaie, Salim; Al-Rasheed, Nawal M; Hasan, Iman H; Mahmoud, Ayman M; Dzimiri, Nduna

2016-03-01

Advances in depression research have targeted inflammation and oxidative stress to develop novel types of treatment. The JAK/STAT signaling pathway plays pivotal roles in immune and inflammatory responses. The present study was designed to investigate the effects of N-acetylcysteine, a putative precursor of the antioxidant glutathione, in an animal model of depression, with an emphasis on the JAK/STAT signaling pathway. Fluoxetine, a classical antidepressant drug was also under investigation. Male Wistar rats were subjected to forced swimming test and given N-acetylcysteine and fluoxetine immediately after the pre-test session, 5 h later and 1 h before the test session of the forced swimming test. N-acetylcysteine decreased immobility time (P < 0.05), serum corticosterone (P < 0.001), and hydrogen peroxide (P < 0.001), while restored glutathione concentration. Treatment of the rats with N-acetylcysteine produced significant (P < 0.001) down-regulation of STAT3 mRNA expression and protein phosphorylation. On the other hand, N-acetylcysteine significantly (P < 0.001) increased SOCS3 gene expression; however, SOCS3 protein was not changed. In conclusion, our study suggests that modulation of the JAK/STAT pathway might mediate the antidepressant-like effects of N-acetylcysteine. Therefore, depression research may target the JAK/STAT signaling pathway to provide a novel effective therapy. © 2015 by the Society for Experimental Biology and Medicine.

Possible involvement of the JAK/STAT signaling pathway in N-acetylcysteine-mediated antidepressant-like effects

PubMed Central

Al-Samhari, Marwa M; Al-Rasheed, Nouf M; Al-Rejaie, Salim; Al-Rasheed, Nawal M; Hasan, Iman H; Dzimiri, Nduna

2015-01-01

Advances in depression research have targeted inflammation and oxidative stress to develop novel types of treatment. The JAK/STAT signaling pathway plays pivotal roles in immune and inflammatory responses. The present study was designed to investigate the effects of N-acetylcysteine, a putative precursor of the antioxidant glutathione, in an animal model of depression, with an emphasis on the JAK/STAT signaling pathway. Fluoxetine, a classical antidepressant drug was also under investigation. Male Wistar rats were subjected to forced swimming test and given N-acetylcysteine and fluoxetine immediately after the pre-test session, 5 h later and 1 h before the test session of the forced swimming test. N-acetylcysteine decreased immobility time (P < 0.05), serum corticosterone (P < 0.001), and hydrogen peroxide (P < 0.001), while restored glutathione concentration. Treatment of the rats with N-acetylcysteine produced significant (P < 0.001) down-regulation of STAT3 mRNA expression and protein phosphorylation. On the other hand, N-acetylcysteine significantly (P < 0.001) increased SOCS3 gene expression; however, SOCS3 protein was not changed. In conclusion, our study suggests that modulation of the JAK/STAT pathway might mediate the antidepressant-like effects of N-acetylcysteine. Therefore, depression research may target the JAK/STAT signaling pathway to provide a novel effective therapy. PMID:26643864

LC/QTOF profile and preliminary stability studies of an enriched flavonoid fraction of Cecropia pachystachya Trécul leaves with potential antidepressant-like activity.

PubMed

Ortmann, Caroline Flach; Abelaira, Helena Mendes; Réus, Gislaine Zilli; Ignácio, Zuleide Maria; Chaves, Vitor Clasen; Dos Santos, Talitha Caldas; de Carvalho, Pâmela; Carlessi, Anelise Scussel; Bruchchen, Livia; Danielski, Lucineia G; Cardoso, Simone Gonçalves; de Campos, Angela Machado; Petronilho, Fabricia; Rebelo, Joyce; Dos Santos Morais, Meline Oliveira; Vuolo, Francieli; Dal-Pizzol, Felipe; Streck, Emilio Luiz; Quevedo, João; Reginatto, Flávio Henrique

2017-11-01

There is increasing interest in natural antioxidants that are candidates for the prevention of brain damage occurring in major depressive disorders. Cecropia pachystachya is a tropical tree species of Central and South America and a rich source of polyphenols, particularly flavonoids. The aim of this study was to characterize the flavonoid profile of an enriched flavonoid fraction of C. pachystachya (EFF-Cp) and evaluate the antidepressant-like effects of its acute administration in behavior, cytokine levels, oxidative stress and energy metabolism parameters. The EFF-Cp chemical characterization was performed by HPLC/DAD and LC/QTOF. The antidepressant-like effects were performed by the forced swimming test, splash test and open field test. EFF-Cp revealed 15 flavonoids, including seven new glycosyl flavonoids for C. pachystachya. Quantitatively, EFF-Cp showed isoorientin (43.46 mg/g), orientin (23.42 mg/g) and isovitexin (17.45 mg/g) as major C-glycosyl flavonoids. In addition, EFF-Cp at doses 50 and 100 mg/kg reduced the immobility time in the forced swimming test, without changing the locomotor activity and grooming time. In addition, EFF-Cp was able to prevent the oxidative damage in some brain areas. In conclusion, the results of this study suggest that EFF-Cp exerts antidepressant-like effects with its antioxidant properties. Copyright © 2017 John Wiley & Sons, Ltd.

Enduring effects of post-weaning rearing condition on depressive- and anxiety-like behaviors and motor activity in male rats.

PubMed

Mosaferi, Belal; Babri, Shirin; Ebrahimi, Hadi; Mohaddes, Gisou

2015-04-01

Environmental manipulation at early critical periods could have long-lasting effects. In spite of the great interest in the biological effects of the environmental condition so far, its long-lasting effects are less documented. This study looks at the enduring effects of rearing condition on tasks that measure affective responses and exploratory behavior in male Wistar rats. The animals were reared from weaning to adulthood in an enriched environment, standard laboratory condition, or isolated condition. Then, all rats were housed in standard laboratory cages to provide a common environment, and successively exposed to different tests between 0 and 11 weeks post-manipulation. The open field test indicated a more efficient exploratory behavior in the enriched group, and an enhanced spontaneous motor activity in both standard and isolated groups. In addition, rats reared in standard condition showed heightened motor activity in forced swimming test and elevated plus maze. Forced swimming test showed an antidepressive-like effect in the enriched environment group by increased climbing behavior. In respect to the anxiety behavior, environmental enrichment improved threat detection ability. It is concluded that rearing condition from weaning to adulthood has important and long-lasting effects on depressive- and anxiety-like and exploratory behaviors as well as motor activity. Copyright © 2015 Elsevier Inc. All rights reserved.

Evidence for the involvement of extinction-associated inhibitory learning in the forced swimming test.

PubMed

Campus, P; Colelli, V; Orsini, C; Sarra, D; Cabib, S

2015-02-01

The forced swimming test (FST) remains one of the most used tools for screening antidepressants in rodent models. Nonetheless, the nature of immobility, its main behavioral measure, is still a matter of debate. The present study took advantage of our recent finding that mice of the inbred DBA/2J strain require a functioning left dorsolateral striatum (DLS) to consolidate long-term memory of FST to test whether immobility is the outcome of stress-related learning. Infusion of the GABA-A agonist muscimol in the left DLS immediately after a single experience of FST prevented and infusion in the left or the right amygdala impaired recall of the acquired levels of immobility in a probe test performed 24h later. Post-training left DLS infusion of muscimol, at a dose capable of preventing retention of FST-induced immobility, did not influence 24h retention of inhibitory avoidance training or of the escape response acquired in a water T-maze. However, this same treatment prevented 24h retention of the extinction training of the consolidated escape response. These results indicate that a left DLS-centered memory system selectively mediates memory consolidation of FST and of escape extinction and support the hypothesis that immobility is the result of extinction-like inhibitory learning involving all available escape responses due to the inescapable/unavoidable nature of FST experience. Copyright © 2014 Elsevier B.V. All rights reserved.

Morphological and functional determinants of fluoxetine (Prozac)-induced pulmonary disease in an experimental model.

PubMed

Capelozzi, Marco A; Leick-Maldonado, Edna A; Parra, Edwin R; Martins, Mílton A; Tibério, Iolanda F L C; Capelozzi, Vera L

2007-05-14

Fluoxetine treatment effects were determined by evaluating respiratory mechanics (elastance/resistance) and exhaled nitric oxide, as well as mononuclear and polymorphonuclear cell recruitment into the lungs, in an experimental guinea pig model. Guinea pigs were divided into four groups: Fl (fluoxetine only, n=7); Fl+Sw (fluoxetine and forced swimming, n=7); Ns+Sw (normal saline and forced swimming, n=8); and Ns (normal saline only, n=8). Treated animals received oral fluoxetine (10 mg/(kg day)) for 30 consecutive days. On day 31, all animals were anesthetized and mechanically ventilated so that respiratory system elastance and resistance, as well exhaled nitric oxide, could be determined. The lungs were then excised en bloc for histological and immunohistochemical evaluation. Forced swimming induced bronchodilation in untreated animals and bronchoconstriction in fluoxetine-treated animals. Fluoxetine treatment was also associated with mononuclear infiltration (predominantly into alveolar walls) and neutrophil recruitment. In addition, levels of exhaled nitric oxide, an inflammatory marker, were higher in fluoxetine-treated animals. Swimming-induced stress also amplified mononuclear cell recruitment to the lungs. These results show that, in this experimental model, fluoxetine treatment reproduces the pathology of chronic interstitial pneumonia in humans.

Hydrodynamic effect of a satellite transmitter on a juvenile green turtle (Chelonia mydas)

PubMed

Watson; Granger

1998-09-01

Wind tunnel tests were performed to measure the effect of a satellite transmitter on a juvenile green turtle (Chelonia mydas). A full-scale turtle model was constructed from an 11.5 kg specimen with a 48 cm carapace length, and a transmitter model was constructed from a Telonics ST-6. The turtle model was tested in a wind tunnel with and without the transmitter, which was mounted on the forward, topmost part of the carapace. Drag, lift and pitch moment were measured for several speeds and flow angles, and the data were scaled for application to the marine environment. At small flow angles representative of straight-line swimming, the transmitter increased drag by 27-30 %, reduced lift by less than 10 % and increased the pitch moment by 11-42 %. On the basis of the drag data at zero angle of attack, it is estimated that the backpack will reduce swimming speed by 11 %, assuming that the turtle produces the same thrust with the unit attached. The drag data are also used to estimate the effect of a transmitter on the swimming energetics of an adult green turtle. Design guidelines are included to minimize the adverse forces and moments caused by the transmitter.

Swim-Training Changes the Spatio-Temporal Dynamics of Skeletogenesis in Zebrafish Larvae (Danio rerio)

PubMed Central

Fiaz, Ansa W.; Léon-Kloosterziel, Karen M.; Gort, Gerrit; Schulte-Merker, Stefan; van Leeuwen, Johan L.; Kranenbarg, Sander

2012-01-01

Fish larvae experience many environmental challenges during development such as variation in water velocity, food availability and predation. The rapid development of structures involved in feeding, respiration and swimming increases the chance of survival. It has been hypothesized that mechanical loading induced by muscle forces plays a role in prioritizing the development of these structures. Mechanical loading by muscle forces has been shown to affect larval and embryonic bone development in vertebrates, but these investigations were limited to the appendicular skeleton. To explore the role of mechanical load during chondrogenesis and osteogenesis of the cranial, axial and appendicular skeleton, we subjected zebrafish larvae to swim-training, which increases physical exercise levels and presumably also mechanical loads, from 5 until 14 days post fertilization. Here we show that an increased swimming activity accelerated growth, chondrogenesis and osteogenesis during larval development in zebrafish. Interestingly, swim-training accelerated both perichondral and intramembranous ossification. Furthermore, swim-training prioritized the formation of cartilage and bone structures in the head and tail region as well as the formation of elements in the anal and dorsal fins. This suggests that an increased swimming activity prioritized the development of structures which play an important role in swimming and thereby increasing the chance of survival in an environment where water velocity increases. Our study is the first to show that already during early zebrafish larval development, skeletal tissue in the cranial, axial and appendicular skeleton is competent to respond to swim-training due to increased water velocities. It demonstrates that changes in water flow conditions can result into significant spatio-temporal changes in skeletogenesis. PMID:22529905

Anisotropic swim stress in active matter with nematic order

NASA Astrophysics Data System (ADS)

Yan, Wen; Brady, John F.

2018-05-01

Active Brownian particles (ABPs) transmit a swim pressure {{{\\Pi }}}{{swim}}=n\\zeta {D}{{swim}} to the container boundaries, where ζ is the drag coefficient, D swim is the swim diffusivity and n is the uniform bulk number density far from the container walls. In this work we extend the notion of the isotropic swim pressure to the anisotropic tensorial swim stress {{\\boldsymbol{σ }}}{{swim}}=-n\\zeta {{\\boldsymbol{D}}}{{swim}}, which is related to the anisotropic swim diffusivity {{\\boldsymbol{D}}}{{swim}}. We demonstrate this relationship with ABPs that achieve nematic orientational order via a bulk external field. The anisotropic swim stress is obtained analytically for dilute ABPs in both 2D and 3D systems. The anisotropy, defined as the ratio of the maximum to the minimum of the three principal stresses, is shown to grow exponentially with the strength of the external field. We verify that the normal component of the anisotropic swim stress applies a pressure {{{\\Pi }}}{{swim}}=-({{\\boldsymbol{σ }}}{{swim}}\\cdot {\\boldsymbol{n}})\\cdot {\\boldsymbol{n}} on a wall with normal vector {\\boldsymbol{n}}, and, through Brownian dynamics simulations, this pressure is shown to be the force per unit area transmitted by the active particles. Since ABPs have no friction with a wall, the difference between the normal and tangential stress components—the normal stress difference—generates a net flow of ABPs along the wall, which is a generic property of active matter systems.

Load response of shape-changing microswimmers scales with their swimming efficiency

NASA Astrophysics Data System (ADS)

Friedrich, Benjamin M.

2018-04-01

External forces acting on a microswimmer can feed back on its self-propulsion mechanism. We discuss this load response for a generic microswimmer that swims by cyclic shape changes. We show that the change in cycle frequency is proportional to the Lighthill efficiency of self-propulsion. As a specific example, we consider Najafi's three-sphere swimmer. The force-velocity relation of a microswimmer implies a correction for a formal superposition principle for active and passive motion.

Dynamics of the vortex wakes of flying and swimming vertebrates.

PubMed

Rayner, J M

1995-01-01

The vortex wakes of flying and swimming animals provide evidence of the history of aero- and hydrodynamic force generation during the locomotor cycle. Vortex-induced momentum flux in the wake is the reaction of forces the animal imposes on its environment, which must be in equilibrium with inertial and external forces. In flying birds and bats, the flapping wings generate lift both to provide thrust and to support the weight. Distinct wingbeat and wake movement patterns can be identified as gaits. In flow visualization experiments, only two wake patterns have been identified: a vortex ring gait with inactive upstroke, and a continuous vortex gait with active upstroke. These gaits may be modelled theoretically by free vortex and lifting line theory to predict mechanical energy consumption, aerodynamic forces and muscle activity. Longer-winged birds undergo a distinct gait change with speed, but shorter-winged species use the vortex ring gait at all speeds. In swimming fish, the situation is more complex: the wake vortices form a reversed von Kármán vortex street, but little is known about the mechanism of generation of the wake, or about how it varies with speed and acceleration or with body form and swimming mode. An unresolved complicating factor is the interaction between the drag wake of the flapping fish body and the thrusting wake from the tail.

Effect of Musa sapientum Stem Extract on Animal Models of Depression

PubMed Central

Reddy, Aditya J.; Handu, Shailendra S.; Dubey, Ashok Kumar; Mediratta, Pramod Kumari; Shukla, Rimi; Ahmed, Qazi Mushtaq

2016-01-01

Background: Musa sapientum, the banana plant, has shown to possess antioxidant activity in previous studies. Oxidative stress has been linked to the pathogenesis of major depressive disorder (MDD) with evidence of increased serum levels of oxidative stress biomarkers in MDD patients. Objective: The present study aimed to evaluate the antidepressant activity of M. sapientum stem extract (MSSE) in experimental models in mice. Materials and Methods: Forced swim test (FST) and tail suspension test (TST) were carried out in five different groups (n = 6/group) of mice. The vehicle, standard drug, and the three test groups were orally administered distilled water (10 mL/kg), fluoxetine (25 mg/kg), and incremental doses of 25, 50, and 100 mg of MSSE, respectively, 45 min prior to the experiment. Results: On FST, the duration of immobility in control group, which was 161.5 ± 6.78 (in seconds, mean ± standard error of mean [SEM]), decreased to 149.33 ± 2.70 (25 mg/kg MSSE), 120.17 ± 8.35 (50 mg/kg MSSE), and 45.17 ± 4.11 (100 mg/kg MSSE) in the treated groups. On TST, the duration of immobility in control group, which was 173.83 ± 12.65 (mean ± SEM), decreased to 163.17 ± 6.91 (25 mg/kg MSSE), 139.0 ± 5.9 (50 mg/kg MSSE), and 124.0 ± 4.42 (100 mg/kg MSSE) in the treated groups. The difference in the duration of immobility was statistically significant at middle and higher doses, i.e. 50 and 100 mg/kg MSSE (P < 0.05) respectively, when compared with the control group in both the tests. Conclusion: A significant antidepressant-like activity was found in MSSE, which could be a potential natural compound for use in depression. SUMMARY The five groups – vehicle, standard drug, and the three test groups were administered distilled water (10 mL/kg), fluoxetine (25 mg/kg), and incremental doses of 25, 50, and 100 mg of Musa sapientum stem extract (MSSE), respectivelyThe duration of immobility decreased in the treated groups as compared to the control group on both, forced swim and tail suspension, testsThe difference in the duration of immobility was statistically significant at middle and higher doses, i.e., 50 and 100 mg/kg MSSE (P < 0.05), when compared with the control group in both the tests. Abbreviations Used: MDD: Major depressive disorder; MSSE: Musa sapientum stem extract; FST: Forced swim test; TST: Tail suspension test; GSH: Glutathione, MDA: Malondialdehyde; SOD: Superoxide dismutase PMID:27695263

Role of GABAA receptors in dorsal raphe nucleus in stress-induced reinstatement of morphine-conditioned place preference in rats.

PubMed

Li, Chen; Staub, Daniel R; Kirby, Lynn G

2013-12-01

The serotonin (5-hydroxytryptamine, 5-HT) system plays an important role in stress-related psychiatric disorders and substance abuse. Our data indicate that stress inhibits the dorsal raphe nucleus (DRN)-5-HT system via stimulation of GABA synaptic activity by the stress neurohormone corticotropin-releasing factor and, more recently, that morphine history sensitizes DRN-5-HT neurons to GABAergic inhibitory effects of stress. We tested the hypothesis that DRN GABAA receptors contribute to stress-induced reinstatement of morphine-conditioned place preference (CPP). First, we tested if activation of GABAA receptors in the DRN would reinstate morphine CPP. Second, we tested if blockade of GABAA receptors in the DRN would attenuate swim stress-induced reinstatement of morphine CPP. CPP was induced by morphine (5 mg/kg) in a 4-day conditioning phase followed by a conditioning test. Upon acquiring conditioning criteria, subjects underwent 4 days of extinction training followed by an extinction test. Upon acquiring extinction criteria, animals underwent a reinstatement test. For the first experiment, the GABAA receptor agonist muscimol (50 ng) or vehicle was injected into the DRN prior to the reinstatement test. For the second experiment, the GABAA receptor antagonist bicuculline (75 ng) or vehicle was injected into the DRN prior to a forced swim stress, and then, animals were tested for reinstatement of CPP. Intraraphe injection of muscimol reinstated morphine CPP, while intraraphe injection of bicuculline attenuated swim stress-induced reinstatement. These data provide evidence that GABAA receptor-mediated inhibition of the serotonergic DRN contributes to stress-induced reinstatement of morphine CPP.

Maximum sustainable speeds and cost of swimming in juvenile kawakawa tuna (Euthynnus affinis) and chub mackerel (Scomber japonicus).

PubMed

Sepulveda, C; Dickson, K A

2000-10-01

Tunas (Scombridae) have been assumed to be among the fastest and most efficient swimmers because they elevate the temperature of the slow-twitch, aerobic locomotor muscle above the ambient water temperature (endothermy) and because of their streamlined body shape and use of the thunniform locomotor mode. The purpose of this study was to test the hypothesis that juvenile tunas swim both faster and more efficiently than their ectothermic relatives. The maximum sustainable swimming speed (U(max), the maximum speed attained while using a steady, continuous gait powered by the aerobic myotomal muscle) and the net cost of transport (COT(net)) were compared at 24 degrees C in similar-sized (116-255 mm fork length) juvenile scombrids, an endothermic tuna, the kawakawa (Euthynnus affinis) and the ectothermic chub mackerel (Scomber japonicus). U(max) and COT(net) were measured by forcing individual fish to swim in a temperature-controlled, variable-speed swimming tunnel respirometer. There were no significant interspecific differences in the relationship between U(max) and body mass or fork length or in the relationship between COT(net) and body mass or fork length. Muscle temperatures were elevated by 1.0-2.3 degrees C and 0.1-0.6 degrees C above water temperature in the kawakawa and chub mackerel, respectively. The juvenile kawakawa had significantly higher standard metabolic rates than the chub mackerel, because the total rate of oxygen consumption at a given swimming speed was higher in the kawakawa when the effects of fish size were accounted for. Thus, juvenile kawakawa are not capable of higher sustainable swimming speeds and are not more efficient swimmers than juvenile chub mackerel.

Granular resistive force theory explains the neuromechanical phase lag during sand-swimming

NASA Astrophysics Data System (ADS)

Ding, Yang; Sharpe, Sarah; Goldman, Daniel

2012-11-01

Undulatory locomotion is a common gait used by a diversity of animals in a range of environments. This mode of locomotion is characterized by the propagation of a traveling wave of body bending, which propels the animal in the opposite direction of the wave. Previous studies of undulatory locomotion in fluids, on land, and even within sand revealed that the wave of muscle activation progresses faster than the traveling wave of curvature. This leads to an increasing phase lag between activation and curvature at more posterior segments, known as the neuromechanical phase lag. In this study, we compare biological measurements of phase lag during the sand-swimming of the sandfish lizard to predictions of a simple model of undulatory swimming that consists of prescribed kinematics and granular resistive forces. The neuromechanical phase lag measured using electromyography (EMG) quantitatively matches the predicted phase lag between the local body curvature and torque exerted by granular resistive forces. Two effects are responsible for the phase lag in this system: the yaw motion of the body and different integration length over a traveling force pattern for different positions along the body.

Embryo developmental capacity of oocytes fertilised by sperm of mouse exposed to forced swimming stress.

PubMed

Ghasem, Saki; Majid, Jasemi; Shiva, Razi

2013-07-01

To assess developmental capacity of fertilised oocytes by sperm of mouse exposed to forced swimming stress. The experimental study was conducted at the Physiology Research Center of Ahvaz Jundishapur University of Medical Sciences, from August 2011 to January 2012. It comprised 20 adult male and 10 female mice. The male mice were randomly divided into two equal groups (n=10): control and experimental. Animals of the experimental group were submitted to forced swimming stress. All male mice were euthanised and the cauda epididymis removed before contents were squeezed out. A pre-incubated capacitated sperm was gently added to the freshly collected ova of the two groups of study. The combined sperm-oocyte suspension was incubated for 4-6 hours under a condition of 5% Carbon dioxide and 37 degreeC temperature. The ova were then washed through several changes of medium and finally incubated. Fertilisation was assessed by recording the number of 1-cell embryos 4-6 hours after insemination. The 1-cell embryos were allowed to further develop in vitro for about 120 hours. Development of embryos everyday and during 5 days of culture was observed by using inverted microscope. SPSS 13.0.1 was used for statistical analysis. The percentage of oocytes fertilised was 75:96 (78.12+/-4.8%) and 50:10 (49.5+/-3.9%) in the control and experimental groups, respectively. The difference was significant (p <0.001). At 24 hours after insemination, 70:75 (93.33+/-2.7%) and 39:50 (78+/-3.5%)of fertilized oocytes developed to two=cell embryos in control and experimental groups respectively.The difference was significant (p <0.02).There were not significant differences (p>0.05) between the two groups in terms of speed and developmental capacity of blastocysts. Fertilisation capacity of male mice affected by forced swimming stress and also the developmental capacity of oocyte fertilised by sperm of mouse exposed to forced swimming stress decreased.

The CRF-1 receptor antagonist, CP-154,526, attenuates stress-induced increases in ethanol consumption by BALB/cJ mice.

PubMed

Lowery, Emily G; Sparrow, Angela M; Breese, George R; Knapp, Darin J; Thiele, Todd E

2008-02-01

Corticotropin-releasing factor (CRF) signaling modulates neurobiological responses to stress and ethanol, and may modulate observed increases in ethanol consumption following exposure to stressful events. The current experiment was conducted to further characterize the role of CRF1 receptor (CRF1R) signaling in stress-induced increases in ethanol consumption in BALB/cJ and C57BL/6N mice. Male BALB/cJ and C57BL/6N mice were given continuous access to 8% (v/v) ethanol and water for the duration of the experiment. When a baseline of ethanol consumption was established, animals were exposed to 5 minutes of forced swim stress on each of 5 consecutive days. Thirty minutes before each forced swim session, animals were given an intraperitoneal injection of a 10 mg/kg dose of CP-154,526, a selective CRF1R antagonist, or an equal volume of vehicle. The effect of forced swim stress exposure on consumption of a 1% (w/v) sucrose solution was also investigated in an ethanol-naïve group of BALB/cJ mice. Exposure to forced swim stress significantly increased ethanol consumption by the BALB/cJ, but not of the C57BL/6N, mice. Stress-induced increases in ethanol consumption were delayed and became evident approximately 3 weeks after the first stressor. Additionally, forced swim stress did not cause increases of food or water intake and did not promote delayed increases of sucrose consumption. Importantly, BALB/cJ mice pretreated with the CRF1R antagonist showed blunted stress-induced increases in ethanol intake, and the CRF1R antagonist did not influence the ethanol drinking of non-stressed mice. The present results provide evidence that CRF1R signaling modulates the delayed increase of ethanol consumption stemming from repeated exposure to a stressful event in BALB/cJ mice.

Forced sustained swimming exercise at optimal speed enhances growth of juvenile yellowtail kingfish (Seriola lalandi).

PubMed

Palstra, Arjan P; Mes, Daan; Kusters, Kasper; Roques, Jonathan A C; Flik, Gert; Kloet, Kees; Blonk, Robbert J W

2014-01-01

Swimming exercise at optimal speed may optimize growth performance of yellowtail kingfish in a recirculating aquaculture system. Therefore, optimal swimming speeds (U opt in m s(-1) or body lengths s(-1), BL s(-1)) were assessed and then applied to determine the effects of long-term forced and sustained swimming at U opt on growth performance of juvenile yellowtail kingfish. U opt was quantified in Blazka-type swim-tunnels for 145, 206, and 311 mm juveniles resulting in values of: (1) 0.70 m s(-1) or 4.83 BL s(-1), (2) 0.82 m s(-1) or 3.25 BL s(-1), and (3) 0.85 m s(-1) or 2.73 BL s(-1). Combined with literature data from larger fish, a relation of U opt (BL s(-1)) = 234.07(BL)(-0.779) (R (2) = 0.9909) was established for this species. Yellowtail kingfish, either forced to perform sustained swimming exercise at an optimal speed of 2.46 BL s(-1) ("swimmers") or allowed to perform spontaneous activity at low water flow ("resters") in a newly designed 3600 L oval flume (with flow created by an impeller driven by an electric motor), were then compared. At the start of the experiment, ten fish were sampled representing the initial condition. After 18 days, swimmers (n = 23) showed a 92% greater increase in BL and 46% greater increase in BW as compared to resters (n = 23). As both groups were fed equal rations, feed conversion ratio (FCR) for swimmers was 1.21 vs. 1.74 for resters. Doppler ultrasound imaging showed a statistically significant higher blood flow (31%) in the ventral aorta of swimmers vs. resters (44 ± 3 vs. 34 ± 3 mL min(-1), respectively, under anesthesia). Thus, growth performance can be rapidly improved by optimal swimming, without larger feed investments.

Forced sustained swimming exercise at optimal speed enhances growth of juvenile yellowtail kingfish (Seriola lalandi)

PubMed Central

Palstra, Arjan P.; Mes, Daan; Kusters, Kasper; Roques, Jonathan A. C.; Flik, Gert; Kloet, Kees; Blonk, Robbert J. W.

2015-01-01

Swimming exercise at optimal speed may optimize growth performance of yellowtail kingfish in a recirculating aquaculture system. Therefore, optimal swimming speeds (Uopt in m s−1 or body lengths s−1, BL s−1) were assessed and then applied to determine the effects of long-term forced and sustained swimming at Uopt on growth performance of juvenile yellowtail kingfish. Uopt was quantified in Blazka-type swim-tunnels for 145, 206, and 311 mm juveniles resulting in values of: (1) 0.70 m s−1 or 4.83 BL s−1, (2) 0.82 m s−1 or 3.25 BL s−1, and (3) 0.85 m s−1 or 2.73 BL s−1. Combined with literature data from larger fish, a relation of Uopt (BL s−1) = 234.07(BL)−0.779 (R2 = 0.9909) was established for this species. Yellowtail kingfish, either forced to perform sustained swimming exercise at an optimal speed of 2.46 BL s−1 (“swimmers”) or allowed to perform spontaneous activity at low water flow (“resters”) in a newly designed 3600 L oval flume (with flow created by an impeller driven by an electric motor), were then compared. At the start of the experiment, ten fish were sampled representing the initial condition. After 18 days, swimmers (n = 23) showed a 92% greater increase in BL and 46% greater increase in BW as compared to resters (n = 23). As both groups were fed equal rations, feed conversion ratio (FCR) for swimmers was 1.21 vs. 1.74 for resters. Doppler ultrasound imaging showed a statistically significant higher blood flow (31%) in the ventral aorta of swimmers vs. resters (44 ± 3 vs. 34 ± 3 mL min−1, respectively, under anesthesia). Thus, growth performance can be rapidly improved by optimal swimming, without larger feed investments. PMID:25620933

Amoeboid swimming in a channel

NASA Astrophysics Data System (ADS)

Wu, Hao; Farutin, Alexander; Hu, Wei-Fan; Thiébaud, Marine; Rafaï, Salima; Peyla, Philippe; Lai, Ming-Chih; Misbah, Chaouqi

Several micro-organisms, such as bacteria, algae, or spermatozoa, use flagella or cilia to swim in a fluid, while many other micro-organisms instead use ample shape deformation, described as amoeboid, to propel themselves by either crawling on a substrate or swimming. Many eukaryotic cells were believed to require an underlying substratum to migrate (crawl) by using membrane deformation (like blebbing or generation of lamellipodia) but there is now increasing evidence that a large variety of cells (including those of the immune system) can migrate without the assistance of focal adhesion, allowing them to swim as efficiently as they can crawl. This paper details the analysis of amoeboid swimming in a confined fluid by modeling the swimmer as an inextensible membrane deploying local active forces. The swimmer displays a rich behavior: it may settle into a straight trajectory in the channel or navigate from one wall to the other depending on its confinement. The nature of the swimmer is also found to be affected by confinement: the swimmer can behave, on the average over one swimming cycle, as a pusher at low confinement, and becomes a puller at higher confinement. The swimmer's nature is thus not an intrinsic property. The scaling of the swimmer velocity V with the force amplitude A is analyzed in detail showing that at small enough A, $V\\sim A^2/\\eta^2$, whereas at large enough A, V is independent of the force and is determined solely by the stroke frequency and swimmer size. This finding starkly contrasts with currently known results found from swimming models where motion is based on flagellar or ciliary activity, where $V\\sim A/\\eta$. To conclude, two definitions of efficiency as put forward in the literature are analyzed with distinct outcomes. We find that one type of efficiency has an optimum as a function of confinement while the other does not. Future perspectives are outlined.

Magnetically actuated and controlled colloidal sphere-pair swimmer

NASA Astrophysics Data System (ADS)

Ran, Sijie; Guez, Allon; Friedman, Gary

2016-12-01

Magnetically actuated swimming of microscopic objects has been attracting attention partly due to its promising applications in the bio-medical field and partly due to interesting physics of swimming in general. While colloidal particles that are free to move in fluid can be an attractive swimming system due it its simplicity and ability to assemble in situ, stability of their dynamics and the possibility of stable swimming behavior in periodically varying magnetic fields has not been considered. Dynamic behavior of two magnetically interacting colloidal particles subjected to rotating magnetic field of switching frequency is analyzed here and is shown to result in stable swimming without any stabilizing feedback. A new mechanism of swimming that relies only on rotations of the particles themselves and of the particle pair axis is found to dominate the swimming dynamics of the colloidal particle pair. Simulation results and analytical arguments demonstrate that this swimming strategy compares favorably to dragging the particles with an external magnetic force when colloidal particle sizes are reduced.

Blonanserin – A Novel Antianxiety and Antidepressant Drug? An Experimental Study

PubMed Central

Limaye, Ramchandra Prabhakar; Patil, Aditi Nitin

2016-01-01

Introduction Many psychiatric disorders show signs and symptoms of anxiety and depression. A drug with both, effects and lesser adverse effects is always desired. Blonanserin is a novel drug with postulated effect on anxiety and depression. Aim The study was aimed to evaluate the effect of Blonanserin on anxiety and depression in animal models. Materials and Methods By using elevated plus maze test and forced swimming test, the antianxiety and antidepressant effects were evaluated. Animal ethics protocols were followed strictly. Total 50 rats (10 rats per group) were used for each test. As a control drug diazepam and imipramine were used in elevated plus maze and forced swimming test respectively. Blonanserin was tested for 3 doses 0.075, 0.2 and 0.8mg. These doses were selected from previous references as well as by extrapolating human doses. Results This study showed an antianxiety effect of Blonanserin comparable to diazepam, which was statistically significant. Optimal effect was observed with 0.075mg, followed by 0.2 and 0.8mg. It also showed an antidepressant effect which was statistically significant. Optimal effect was observed at 0.2mg dose. Conclusion The results showed that at a dose range of 0.075 and 0.2mg Blonanserin has potential to exert an adjuvant antianxiety and antidepressant activity in animal models. In order to extrapolate this in patient, longer clinical studies with comparable doses should be planned. The present study underlines potential of Blonanserin as a novel drug for such studies. PMID:27790460

Blonanserin - A Novel Antianxiety and Antidepressant Drug? An Experimental Study.

PubMed

Limaye, Ramchandra Prabhakar; Patil, Aditi Nitin

2016-09-01

Many psychiatric disorders show signs and symptoms of anxiety and depression. A drug with both, effects and lesser adverse effects is always desired. Blonanserin is a novel drug with postulated effect on anxiety and depression. The study was aimed to evaluate the effect of Blonanserin on anxiety and depression in animal models. By using elevated plus maze test and forced swimming test, the antianxiety and antidepressant effects were evaluated. Animal ethics protocols were followed strictly. Total 50 rats (10 rats per group) were used for each test. As a control drug diazepam and imipramine were used in elevated plus maze and forced swimming test respectively. Blonanserin was tested for 3 doses 0.075, 0.2 and 0.8mg. These doses were selected from previous references as well as by extrapolating human doses. This study showed an antianxiety effect of Blonanserin comparable to diazepam, which was statistically significant. Optimal effect was observed with 0.075mg, followed by 0.2 and 0.8mg. It also showed an antidepressant effect which was statistically significant. Optimal effect was observed at 0.2mg dose. The results showed that at a dose range of 0.075 and 0.2mg Blonanserin has potential to exert an adjuvant antianxiety and antidepressant activity in animal models. In order to extrapolate this in patient, longer clinical studies with comparable doses should be planned. The present study underlines potential of Blonanserin as a novel drug for such studies.

Chronic treatment with fluoxetine and sertraline prevents forced swimming test-induced hypercontractility of rat detrusor muscle.

PubMed

Bilge, Sirri; Bozkurt, Ayhan; Bas, Duygu B; Aksoz, Elif; Savli, Evren; Ilkaya, Fatih; Kesim, Yuksel

2008-01-01

Serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitors represent important targets for the development of new treatments for detrusor overactivity and urinary incontinence. The present study was undertaken to investigate the effects of the forced swimming test (FST) on the contractile response of isolated rat detrusor muscle and to examine the effects of in vivo treatments of fluoxetine and sertraline on altered detrusor muscle contractility. Fluoxetine (20 mg/kg ip) and sertraline (10 mg/kg ip) were administered once a day for 14 days. Rats were exposed to the FST on the 15th day. After the test, detrusor muscles were removed and placed in organ baths, and the contraction responses induced by carbachol, potassium chloride (KCl) and electrical field stimulation (EFS) were recorded. The contractile responses of detrusor muscle strips to carbachol and electrical field stimulation were found to be increased at all carbachol doses and frequencies, respectively. FST also increased the contractile responses to KCl, which is used to test the differences in postreceptor-mediated contractions. The hypercontractile responses of detrusor strips to carbachol, EFS and KCl were abolished by treatment with both fluoxetine and sertraline. These treatments also decreased the immobility duration in the FST consistent with an antidepressant-like effect in this test. The results of this study provide the first evidence that FST increases contractility of the rat detrusor muscle, and this hypercontractility was abolished by chronic treatments of fluoxetine and sertraline at antidepressant doses by decreasing the postreceptor-mediated events.

Behavioural profiles of two Wistar rat lines selectively bred for high or low anxiety-related behaviour.

PubMed

Liebsch, G; Montkowski, A; Holsboer, F; Landgraf, R

1998-08-01

Over the past years, two breeding lines, derived originally from outbred Wistar rats, have been established that differ markedly and consistently in their anxiety-related behaviour in the elevated plus-maze. At the age of ten weeks, rats were tested once on the elevated plus-maze and the males and females displaying the most anxious and the least anxious behaviour were sib-mated to start a new generation of the high anxiety-related behaviour (HAB) and the low anxiety-related behaviour (LAB) lines, respectively. The resulting difference in emotionality between these two lines was also evident in an open field test and correlated with differences in the forced swim test. In the open field, the HAB rats tended to be less active and explored the central zone of the open field much less than the LAB animals. In the forced swim test, HAB rats started floating earlier, spent significantly more time in this immobile posture and struggled less than LAB rats. However, in an olfactory-cued social discrimination task there was no difference between male and female animals from either line. The overall performance in these various behavioural tests suggests that selective breeding has resulted in rat lines not only differing markedly in their innate anxiety-related behaviour in the plus-maze, but also in other stress-related behavioural performances, suggesting a close link between the emotional evaluation of a novel and stressful situation and an individual's coping strategy.

Toxicological analysis and antihyperalgesic, antidepressant, and anti-inflammatory effects of Campomanesia adamantium fruit barks.

PubMed

de Souza, Juliane C; Piccinelli, Ana Cláudia; Aquino, Diana F S; de Souza, Vanessa V; Schmitz, Wanderlei O; Traesel, Giseli K; Cardoso, Claudia A L; Kassuya, Candida A L; Arena, Arielle C

2017-01-01

This study evaluates the anti-inflammatory, antihyperalgesic, and antidepressive potential of the hydroalcoholic extract of Campomanesia adamantium fruit barks (CAE) on rodents and determines the safety of this plant. The acute toxicity of CAE was evaluated by oral administration to female rats as single doses of 0, 500, 1000, or 2000 mg/kg body weight. General behavior and toxic symptoms were observed for 14 days. In the subacute toxicity test, male and female rats received 125 or 250 mg/kg body weight of CAE for 28 days. The oral anti-inflammatory activity of CAE was evaluated in carrageenan-induced pleurisy in male mice. The effect of treatment with CAE (100 mg/kg) for 15 days was evaluated in mechanical hyperalgesia (electronic von Frey), depressive behavior (forced swimming test), and cold hypersensitivity in spared nerve injury (SNI) model in rats. No clinical signs of toxicity were observed in animals from the experimental groups during acute and subacute exposure to CAE. At pleurisy test, the oral administration of CAE significantly inhibited leukocyte migration and protein leakage at all doses tested when compared to control. Oral administration of CAE for 3-15 days significantly inhibited SNI-induced mechanical hyperalgesia and increased immobility in the forced swim test. Finally, on the 15th day, oral treatment with CAE prevented the increase in sensitivity to a cold stimulus induced by SNI. The present study shows that C. adamantium extract has anti-inflammatory, antihyperalgesic, and antidepressive properties in rodents without causing toxicity.

Circular swimming in mice after exposure to a high magnetic field.

PubMed

Houpt, Thomas A; Houpt, Charles E

2010-06-16

There is increasing evidence that exposure to high magnetic fields of 4T and above perturbs the vestibular system of rodents and humans. Performance in a swim test is a sensitive test of vestibular function. In order to determine the effect of magnet field exposure on swimming in mice, mice were exposed for 30 min within a 14.1T superconducting magnet and then tested at different times after exposure in a 2-min swim test. As previously observed in open field tests, mice swam in tight counter-clockwise circles when tested immediately after magnet exposure. The counter-clockwise orientation persisted throughout the 2-min swim test. The tendency to circle was transient, because no significant circling was observed when mice were tested at 3 min or later after magnet exposure. However, mice did show a decrease in total distance swum when tested between 3 and 40 min after magnet exposure. The decrease in swimming distance was accompanied by a pronounced postural change involving a counter-clockwise twist of the pelvis and hindlimbs that was particularly severe in the first 15s of the swim test. Finally, no persistent difference from sham-exposed mice was seen in the swimming of magnet-exposed mice when tested 60 min, 24h, or 96 h after magnet exposure. This suggests that there is no long-lasting effect of magnet exposure on the ability of mice to orient or swim. The transient deficits in swimming and posture seen shortly after magnet exposure are consistent with an acute perturbation of the vestibular system by the high magnetic field. (c) 2010 Elsevier Inc. All rights reserved.

Analysis of swimming motions.

NASA Technical Reports Server (NTRS)

Gallenstein, J.; Huston, R. L.

1973-01-01

This paper presents an analysis of swimming motion with specific attention given to the flutter kick, the breast-stroke kick, and the breast stroke. The analysis is completely theoretical. It employs a mathematical model of the human body consisting of frustrums of elliptical cones. Dynamical equations are written for this model including both viscous and inertia forces. These equations are then applied with approximated swimming strokes and solved numerically using a digital computer. The procedure is to specify the input of the swimming motion. The computer solution then provides the output displacement, velocity, and rotation or body roll of the swimmer.

Drug discovery: phosphinolactone, in vivo bioisostere of the lactol group.

PubMed

Volle, Jean-Noël; Filippini, Damien; Krawczy, Bartlomiej; Kaloyanov, Nikolay; Van der Lee, Arie; Maurice, Tangui; Pirat, Jean-Luc; Virieux, David

2010-03-21

In drug discovery, structural modifications over the lead molecule are often crucial for the development of a drug. Herein, we reported the first in vivo bioisosteric effect of phosphinolactone function in relation to the lactol group constituting the bioactive molecule: Hydroxybupropion. The preparation of phosphinolactone analogues and their antidepressant evaluation towards forced swimming test in mice showed that biological activity was regained and even strengthen.

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.

Great hammerhead sharks swim on their side to reduce transport costs

PubMed Central

Payne, Nicholas L.; Iosilevskii, Gil; Barnett, Adam; Fischer, Chris; Graham, Rachel T.; Gleiss, Adrian C.; Watanabe, Yuuki Y.

2016-01-01

Animals exhibit various physiological and behavioural strategies for minimizing travel costs. Fins of aquatic animals play key roles in efficient travel and, for sharks, the functions of dorsal and pectoral fins are considered well divided: the former assists propulsion and generates lateral hydrodynamic forces during turns and the latter generates vertical forces that offset sharks' negative buoyancy. Here we show that great hammerhead sharks drastically reconfigure the function of these structures, using an exaggerated dorsal fin to generate lift by swimming rolled on their side. Tagged wild sharks spend up to 90% of time swimming at roll angles between 50° and 75°, and hydrodynamic modelling shows that doing so reduces drag—and in turn, the cost of transport—by around 10% compared with traditional upright swimming. Employment of such a strongly selected feature for such a unique purpose raises interesting questions about evolutionary pathways to hydrodynamic adaptations, and our perception of form and function. PMID:27457414

Simultaneous measurement of bacterial flagellar rotation rate and swimming speed.

PubMed Central

Magariyama, Y; Sugiyama, S; Muramoto, K; Kawagishi, I; Imae, Y; Kudo, S

1995-01-01

Swimming speeds and flagellar rotation rates of individual free-swimming Vibrio alginolyticus cells were measured simultaneously by laser dark-field microscopy at 25, 30, and 35 degrees C. A roughly linear relation between swimming speed and flagellar rotation rate was observed. The ratio of swimming speed to flagellar rotation rate was 0.113 microns, which indicated that a cell progressed by 7% of pitch of flagellar helix during one flagellar rotation. At each temperature, however, swimming speed had a tendency to saturate at high flagellar rotation rate. That is, the cell with a faster-rotating flagellum did not always swim faster. To analyze the bacterial motion, we proposed a model in which the torque characteristics of the flagellar motor were considered. The model could be analytically solved, and it qualitatively explained the experimental results. The discrepancy between the experimental and the calculated ratios of swimming speed to flagellar rotation rate was about 20%. The apparent saturation in swimming speed was considered to be caused by shorter flagella that rotated faster but produced less propelling force. Images FIGURE 1 FIGURE 4 PMID:8580359

Propulsive efficiency of frog swimming with different feet and swimming patterns

PubMed Central

Jizhuang, Fan; Wei, Zhang; Bowen, Yuan; Gangfeng, Liu

2017-01-01

ABSTRACT Aquatic and terrestrial animals have different swimming performances and mechanical efficiencies based on their different swimming methods. To explore propulsion in swimming frogs, this study calculated mechanical efficiencies based on data describing aquatic and terrestrial webbed-foot shapes and swimming patterns. First, a simplified frog model and dynamic equation were established, and hydrodynamic forces on the foot were computed according to computational fluid dynamic calculations. Then, a two-link mechanism was used to stand in for the diverse and complicated hind legs found in different frog species, in order to simplify the input work calculation. Joint torques were derived based on the virtual work principle to compute the efficiency of foot propulsion. Finally, two feet and swimming patterns were combined to compute propulsive efficiency. The aquatic frog demonstrated a propulsive efficiency (43.11%) between those of drag-based and lift-based propulsions, while the terrestrial frog efficiency (29.58%) fell within the range of drag-based propulsion. The results illustrate the main factor of swimming patterns for swimming performance and efficiency. PMID:28302669

The Complex Hydrodynamics of Swimming in the Spanish Dancer

NASA Astrophysics Data System (ADS)

Zhou, Zhuoyu; Mittal, Rajat

2016-11-01

The lack of a vertebra seems to have freed marine gastropods to explore and exploit a stupendous variety of swimming kinematics. In fact, examination of just a few animals in this group reveal locomotory modes ranging from insect-like flapping, to fish-like undulatory swimming, jet propulsion, and rajiform (manta-like) swimming. There are also a number of marine gastropods that have bizarre swimming gaits with no equivalent among fish or marine mammals. In this latter category is the Spanish Dancer (Hexabranchus sanguineus) a sea slug that swims with a complex combination of body undulations and flapping parapodia. While the neurobiology of these animals has been relatively well-studied, less is known about their propulsive mechanism and swimming energetics. In this study, we focus on the hydrodynamics of two distinct swimmers: the Spanish Dancer, and the sea hare Aplysia; the latter adopts a rajiform-like mode of swimming by passing travelling waves along its parapodia. In the present study an immersed boundary method is employed to examine the vortex structures, hydrodynamic forces and energy costs of the swimming in these animals. NSF Grant No. 1246317.

Volumetric PIV of multiple free-swimming maneuvers generated by the KnifeBot: a biomimetic vessel propelled by an undulating fin

NASA Astrophysics Data System (ADS)

Liu, Hanlin; Troolin, Daniel; Hortensius, Ruben; Pothos, Stamatios; Curet, Oscar

2017-11-01

An undulating fin represents a remarkable propulsion model for underwater vehicles due to its high propulsive efficiency and considerable locomotor capabilities. In this work, we used a bio-inspired vessel, the KnifeBot to demonstrate the maneuverability of undulating fin propulsion, including forward-backward swimming, station keeping and vertical swimming. This self-contained robotic system uses an undulating ventral fin as the propulsor and features a slender 3D-printed hull with 16 motors, 2 batteries and electronic boards encapsulated inside. We tested the robot in a water-filled tank and used volumetric particle image velocimetry (V3V PIV) to investigate the three-dimensional flow features and vortex structures generated by the undulating ribbon fin in free-swimming maneuvers. Our results indicate that in the forward swimming, a series of vortex tubes are shed off the fin edge. A streamwise jet at an oblique angle to the fin is generated in association with the vortex tubes propelling the robot forward as well as pitching it up. For the hovering maneuver with inward counter-propagating waves. The streamlines develop vertically downward with the tip vortex shed from the fin edge. This downward jet provides substantial heave force for the robot to swim upward or perform station keeping. Our findings will be useful for understanding the mechanical basis of undulating fin propulsion and facilitate the development of bio-inspired vehicles using undulatory propellers. Office of Naval Research under Award Number N00014-16-1-2505.

Anti-HIV drugs nevirapine and efavirenz affect anxiety-related behavior and cognitive performance in mice.

PubMed

Romão, Pedro R T; Lemos, Joelson C; Moreira, Jeverson; de Chaves, Gisele; Moretti, Morgana; Castro, Adalberto A; Andrade, Vanessa M; Boeck, Carina R; Quevedo, João; Gavioli, Elaine C

2011-01-01

Nevirapine (NVP) and efavirenz (EFV) belong to the class of anti-HIV drugs called non-nucleoside reverse transcriptase inhibitors (NNRTIs), commonly used as part of highly active antiretroviral therapy (HAART). Although the HAART is able to bring down viral load to undetectable levels and restore immune function, their prolonged use causes several adverse effects. It has been demonstrated that both NVP and EFV are able to cross the blood-brain barrier, causing important central nervous system-related side effects. Thus, this study investigated the effects of chronic administration of EFV (10 mg/kg) and NVP (3.3 mg/kg) in mice submitted to two distinct series of experiments, which aimed to evaluate: (1) the emotional behavior (elevated plus-maze, forced swimming, and open-field test) and (2) the cognitive performance (object recognition and inhibitory avoidance test) of mice. Our results demonstrated that EFV, but not NVP, reduced the exploration to open arms in the elevated plus-maze test. Neither NVP nor EFV altered mouse behavior in the forced swimming and open-field tests. Both drugs reduced the recognition index in the object recognition test, but only EFV significantly impaired the aversive memory assessed in the inhibitory avoidance test 24 h after training. In conclusion, our findings point to a genuine anxiogenic-like effect to EFV, since it reduced exploration to open arms of elevated plus-maze test without affecting spontaneous locomotion. Additionally, both drugs impaired recognition memory, while only the treatment with EFV impaired significantly aversive memory.

Efficient swimming of an assembly of rigid spheres at low Reynolds number.

PubMed

Felderhof, B U

2015-08-01

The swimming of an assembly of rigid spheres immersed in a viscous fluid of infinite extent is studied in low-Reynolds-number hydrodynamics. The instantaneous swimming velocity and rate of dissipation are expressed in terms of the time-dependent displacements of sphere centers about their collective motion. For small-amplitude swimming with periodically oscillating displacements, optimization of the mean swimming speed at given mean power leads to an eigenvalue problem involving a velocity matrix and a power matrix. The corresponding optimal stroke permits generalization to large-amplitude motion in a model of spheres with harmonic interactions and corresponding actuating forces. The method allows straightforward calculation of the swimming performance of structures modeled as assemblies of interacting rigid spheres. A model of three collinear spheres with motion along the common axis is studied as an example.

Integration of animal behaviors under stresses with different time courses

PubMed Central

Zheng, Lun; Zheng, Xigeng

2014-01-01

We used animal models of “forced swim stress” and “chronic unpredictable stress”, and tried to reveal whether a passive coping style of high flotation behavior in forced swim stress predicts anhedonia behavior after chronic unpredictable stress, and whether the dopamine system regulates floating and anhedonia behaviors. Our results confirmed that depression-prone rats use “floating behavior” as a coping strategy in forced swim stress and more readily suffer from anhedonia during chronic unpredictable stress. Intraperitoneal injection or nucleus accumbens microinjection of the dopamine 2/3 receptor subtype agonist ropinirole reduced floating behaviors in depression-prone animals, but increased sucrose preference in rats showing anhedonia. These data indicate that floating behavior is a defensive mode that is preferred by susceptible individuals under conditions of acute stress. Simultaneously, these animals more readily experienced anhedonia under long-term stress; that is, they were more readily affected by depression. Our results suggest that dopamine 2/3 receptor subtypes in the nucleus accumbens play an important role in floating behaviors and anhedonia. PMID:25317159

Dynamic states of swimming bacteria in a nematic liquid crystal cell with homeotropic alignment

DOE PAGES

Zhou, Shuang; Tovkach, Oleh; Golovaty, Dmitry; ...

2017-05-17

Flagellated bacteria such as Escherichia coli and Bacillus subtilis exhibit effective mechanisms for swimming in fluids and exploring the surrounding environment. In isotropic fluids such as water, the bacteria change swimming direction through the run-and-tumble process. Lyotropic chromonic liquid crystals (LCLCs) have been introduced recently as an anisotropic environment in which the direction of preferred orientation, the director, guides the bacterial trajectories. In this work, we describe the behavior of bacteria B. subtilis in a homeotropic LCLC geometry, in which the director is perpendicular to the bounding plates of a shallow cell. We demonstrate that the bacteria are capable ofmore » overcoming the stabilizing elastic forces of the LCLC and swim perpendicularly to the imposed director (and parallel to the bounding plates). The effect is explained by a finite surface anchoring of the director at the bacterial body; the role of surface anchoring is analyzed by numerical simulations of a rod realigning in an otherwise uniform director field. Shear flows produced by a swimming bacterium cause director distortions around its body, as evidenced both by experiments and numerical simulations. These distortions contribute to a repulsive force that keeps the swimming bacterium at a distance of a few micrometers away from the bounding plates. The homeotropic alignment of the director imposes two different scenarios of bacterial tumbling: one with an 180° reversal of the horizontal velocity and the other with the realignment of the bacterium by two consecutive 90° turns. Finally, in the second case, the angle between the bacterial body and the imposed director changes from 90° to 0° and then back to 90°; the new direction of swimming does not correlate with the previous swimming direction.« less

Dynamic states of swimming bacteria in a nematic liquid crystal cell with homeotropic alignment

NASA Astrophysics Data System (ADS)

Zhou, Shuang; Tovkach, Oleh; Golovaty, Dmitry; Sokolov, Andrey; Aranson, Igor S.; Lavrentovich, Oleg D.

2017-05-01

Flagellated bacteria such as Escherichia coli and Bacillus subtilis exhibit effective mechanisms for swimming in fluids and exploring the surrounding environment. In isotropic fluids such as water, the bacteria change swimming direction through the run-and-tumble process. Lyotropic chromonic liquid crystals (LCLCs) have been introduced recently as an anisotropic environment in which the direction of preferred orientation, the director, guides the bacterial trajectories. In this work, we describe the behavior of bacteria B. subtilis in a homeotropic LCLC geometry, in which the director is perpendicular to the bounding plates of a shallow cell. We demonstrate that the bacteria are capable of overcoming the stabilizing elastic forces of the LCLC and swim perpendicularly to the imposed director (and parallel to the bounding plates). The effect is explained by a finite surface anchoring of the director at the bacterial body; the role of surface anchoring is analyzed by numerical simulations of a rod realigning in an otherwise uniform director field. Shear flows produced by a swimming bacterium cause director distortions around its body, as evidenced both by experiments and numerical simulations. These distortions contribute to a repulsive force that keeps the swimming bacterium at a distance of a few micrometers away from the bounding plates. The homeotropic alignment of the director imposes two different scenarios of bacterial tumbling: one with an 180° reversal of the horizontal velocity and the other with the realignment of the bacterium by two consecutive 90° turns. In the second case, the angle between the bacterial body and the imposed director changes from 90° to 0° and then back to 90° the new direction of swimming does not correlate with the previous swimming direction.

Effectiveness of the Power Dry-Land Training Programmes in Youth Swimmers

PubMed Central

Sadowski, Jerzy; Mastalerz, Andrzej; Gromisz, Wilhelm; NiŸnikowski, Tomasz

2012-01-01

The aim of the study was to evaluate the effects of the dry-land power training on swimming force, swimming performance and strength in youth swimmers. Twenty six male swimmers, free from injuries and training regularly at least 6 times a week, were enrolled in the study and randomly assigned to one of two groups: experimental (n=14, mean age 14.0 ± 0.5 yrs, mean height 1.67±0.08 m and mean body mass 55.71 ±9.55 kg) and control (n=12, mean age 14.1 ± 0.5 yrs, mean height 1.61±0.11 m and mean body mass 49.07 ±8.25 kg). The experimental group took part in a combined swimming and dry-land power training. The control group took part in swimming training only. The training programmes in water included a dominant aerobic work in front crawl. In this research the experimental group tended to present slightly greater improvements in sprint performance. However, the stroke frequency insignificantly decreased (−4.30%, p>0.05) in the experimental group and increased (6.28%, p>0.05) in the control group. The distance per stroke insignificantly increased in the experimental group (5.98%, p>0.05) and insignificantly decreased in the control group (−5.36%, p>0.05). A significant improvement of tethered swimming force for the experimental group (9.64%, p<0.02) was found, whereas the increase was not statistically significant in the control group (2.86%, p>0.05). The main data cannot clearly state that power training allowed an enhancement in swimming performance, although a tendency to improve swimming performance in tethered swimming was noticed. PMID:23486353

Evaluation of the ergogenic potential of noni juice.

PubMed

Ma, De-lu; West, Brett J; Su, Chen X; Gao, Jian-hua; Liu, Tin-zhong; Liu, Yu-Wen

2007-11-01

Morinda citrifolia (noni) fruit juice is an increasingly popular health food with many reported benefits, such as antioxidant and immunomodulatory properties. Traditionally, noni fruit was used by Polynesians to combat fatigue. Also, clinical studies have revealed that noni juice consumption improves quality of life scores related to physical functioning and energy levels. To further evaluate the ergogenic (antifatigue and endurance promoting) potential of noni juice, aged mice were pretreated orally with increasing doses (10, 20 and 40 mL/kg body weight) of Tahitian Noni Juice (TNJ) and then compared with young and aged controls in the forced swim test and rotarod test. The average times of all TNJ dose groups were significantly longer than the aged controls in both the swim test (36% to 45%) and the rotarod test (59% to 128%), and were similar to those of the young controls. This demonstrates not only an improvement in endurance but also in balance and flexibility. These results confirm the reported use of noni juice to combat fatigue, improve endurance and increase overall physical performance. Copyright (c) 2007 John Wiley & Sons, Ltd.

Modeling hydrodynamic self-propulsion with Stokesian Dynamics. Or teaching Stokesian Dynamics to swim

NASA Astrophysics Data System (ADS)

Swan, James W.; Brady, John F.; Moore, Rachel S.; ChE 174

2011-07-01

We develop a general framework for modeling the hydrodynamic self-propulsion (i.e., swimming) of bodies (e.g., microorganisms) at low Reynolds number via Stokesian Dynamics simulations. The swimming body is composed of many spherical particles constrained to form an assembly that deforms via relative motion of its constituent particles. The resistance tensor describing the hydrodynamic interactions among the individual particles maps directly onto that for the assembly. Specifying a particular swimming gait and imposing the condition that the swimming body is force- and torque-free determine the propulsive speed. The body's translational and rotational velocities computed via this methodology are identical in form to that from the classical theory for the swimming of arbitrary bodies at low Reynolds number. We illustrate the generality of the method through simulations of a wide array of swimming bodies: pushers and pullers, spinners, the Taylor/Purcell swimming toroid, Taylor's helical swimmer, Purcell's three-link swimmer, and an amoeba-like body undergoing large-scale deformation. An open source code is a part of the supplementary material and can be used to simulate the swimming of a body with arbitrary geometry and swimming gait.

Floppy swimming: Viscous locomotion of actuated elastica

NASA Astrophysics Data System (ADS)

Lauga, Eric

2007-04-01

Actuating periodically an elastic filament in a viscous liquid generally breaks the constraints of Purcell’s scallop theorem, resulting in the generation of a net propulsive force. This observation suggests a method to design simple swimming devices—which we call “elastic swimmers”—where the actuation mechanism is embedded in a solid body and the resulting swimmer is free to move. In this paper, we study theoretically the kinematics of elastic swimming. After discussing the basic physical picture of the phenomenon and the expected scaling relationships, we derive analytically the elastic swimming velocities in the limit of small actuation amplitude. The emphasis is on the coupling between the two unknowns of the problems—namely the shape of the elastic filament and the swimming kinematics—which have to be solved simultaneously. We then compute the performance of the resulting swimming device and its dependence on geometry. The optimal actuation frequency and body shapes are derived and a discussion of filament shapes and internal torques is presented. Swimming using multiple elastic filaments is discussed, and simple strategies are presented which result in straight swimming trajectories. Finally, we compare the performance of elastic swimming with that of swimming micro-organisms.

Effect of ginsenoside Rg3 on tyrosine hydroxylase and related mechanisms in the forced swimming-induced fatigue rats.

PubMed

Xu, Yuxia; Zhang, Peng; Wang, Chu; Shan, Ye; Wang, Dandan; Qian, Fenglei; Sun, Mengwei; Zhu, Cuiqing

2013-10-28

Ginsenoside Rg3 has shown multiple pharmacological activities and been considered as one of the most promising approaches for fatigue treatment. However, little is known about the cellular and molecular mechanisms of Rg3 on anti-fatigue and the effect of Rg3 on dopaminergic system has not been reported yet. The major aim of this study is to investigate the effect of Rg3 on TH expression and the related biochemical parameters, such as PKAα, ERK1/2, Akt and α-synuclein in brain of fatigue rats. Weight-loaded forced swimming was performed to establish an animal model of fatigue. Rg3 (10mg/kg, 50mg/kg and 100mg/kg) was intragastrically administrated before swimming. The effect of Rg3 on the expression and phosphorylation of TH and TH-related proteins in fatigue rats or in SH-SY5Y cells was assessed with western blotting. HPLC was used to examine the level of DA and DOPAC in the fatigue rats tissues. TH and phosphorylated TH were decreased in different brain regions of which ventral midbrain were less affected in weight-loaded forced swimming rats. Pretreatment with Rg3 significantly suppressed fatigue-induced decrease expression of TH and TH phosphorylation. Also treatment with Rg3 reversed the decrease expression of PKAα as well as the phosphorylation of ERK1/2 and Akt which were induced by weight-loaded forced swimming. Moreover, weight-loaded swimming could induce the increase expression of α-synuclein in hippocampus and midbrain, while suppressed α-synuclein expression in striatum and prefrontal cortex. Furthermore, Rg3 could induce the increase of TH expression and phosphorylation which was accompanied with elevated expression and phosphorylation of related kinase proteins in vitro, while the inhibitors of kinase proteins could suppress these effects of Rg3. In addition, HPLC results showed that Rg3 could reverse the weight-loaded swimming-induced increase of DOPAC/DA ratio. Our data suggest that fatigue can induce the decrease of DA which might partially result from the change of TH expression and phosphorylation, and Rg3 can reverse these fatigue-induced changes. The underling mechanisms may include the activity changes of PKAα, ERK1/2, Akt and α-synuclein. © 2013 Published by Elsevier Ireland Ltd.

Diagnosis and early detection of CNS-SLE in MRL/lpr mice using peptide microarrays.

PubMed

Williams, Stephanie; Stafford, Phillip; Hoffman, Steven A

2014-06-07

An accurate method that can diagnose and predict lupus and its neuropsychiatric manifestations is essential since currently there are no reliable methods. Autoantibodies to a varied panel of antigens in the body are characteristic of lupus. In this study we investigated whether serum autoantibody binding patterns on random-sequence peptide microarrays (immunosignaturing) can be used for diagnosing and predicting the onset of lupus and its central nervous system (CNS) manifestations. We also tested the techniques for identifying potentially pathogenic autoantibodies in CNS-Lupus. We used the well-characterized MRL/lpr lupus animal model in two studies as a first step to develop and evaluate future studies in humans. In study one we identified possible diagnostic peptides for both lupus and altered behavior in the forced swim test. When comparing the results of study one to that of study two (carried out in a similar manner), we further identified potential peptides that may be diagnostic and predictive of both lupus and altered behavior in the forced swim test. We also characterized five potentially pathogenic brain-reactive autoantibodies, as well as suggested possible brain targets. These results indicate that immunosignaturing could predict and diagnose lupus and its CNS manifestations. It can also be used to characterize pathogenic autoantibodies, which may help to better understand the underlying mechanisms of CNS-Lupus.

Possible involvement of ATP-sensitive potassium channels in the antidepressant-like effects of gabapentin in mouse forced swimming test.

PubMed

Ostadhadi, Sattar; Akbarian, Reyhaneh; Norouzi-Javidan, Abbas; Nikoui, Vahid; Zolfaghari, Samira; Chamanara, Mohsen; Dehpour, Ahmad-Reza

2017-07-01

Gabapentin as an anticonvulsant drug also has beneficial effects in treatment of depression. Previously, we showed that acute administration of gabapentin produced an antidepressant-like effect in the mouse forced swimming test (FST) by a mechanism that involves the inhibition of nitric oxide (NO). Considering the involvement of NO in adenosine triphosphate (ATP)-sensitive potassium channels (K ATP ), in the present study we investigated the involvement of K ATP channels in antidepressant-like effect of gabapentin. Gabapentin at different doses (5-10 mg/kg) and fluoxetine (20 mg/kg) were administrated by intraperitoneal route, 60 and 30 min, respectively, before the test. To clarify the probable involvement of K ATP channels, mice were pretreated with K ATP channel inhibitor or opener. Gabapentin at dose 10 mg/kg significantly decreased the immobility behavior of mice similar to fluoxetine (20 mg/kg). Co-administration of subeffective dose (1 mg/kg) of glibenclamide (inhibitor of K ATP channels) with gabapentin (3 mg/kg) showed a synergistic antidepressant-like effect. Also, subeffective dose of cromakalim (opener of K ATP channels, 0.1 mg/kg) inhibited the antidepressant-like effect of gabapentin (10 mg/kg). None of the treatments had any impact on the locomotor movement. Our study, for the first time, revealed that antidepressant-like effect of gabapentin in mice is mediated by blocking the K ATP channels.

Experimental hydrodynamics of swimming in fishes

NASA Astrophysics Data System (ADS)

Tytell, Eric Daniel

2005-11-01

The great diversity of fish body shapes suggests that they have adapted to different selective pressures. For many fishes, the pressures include hydrodynamic demands: swimming efficiently or accelerating rapidly, for instance. However, the hydrodynamic advantages or disadvantages to specific morphologies are poorly understood. In particular, eels have been considered inefficient swimmers, but they migrate long distances without feeding, a task that requires efficient swimming. This dissertation, therefore, begins with an examination of the swimming hydrodynamics of American eels, Anguilla rostrata, at steady swimming speeds from 0.5 to 2 body lengths (L) per second and during accelerations from -1.4 to 1.3 L s -2. The final chapter examines the hydrodynamic effects of body shape directly by describing three-dimensional flow around swimming bluegill sunfish, Lepomis macrochirus. In all chapters, flow is quantified using digital particle image velocimetry, and simultaneous kinematics are measured from high-resolution digital video. The wake behind a swimming eel in the horizontal midline plane is described first. Rather than producing a wake with fluid jets angled backwards, like in fishes such as sunfish, eels have a wake with exclusively lateral jets. The lack of downstream momentum indicates that eels balance the axial forces of thrust and drag evenly over time and over their bodies, and therefore do not change axial fluid momentum. This even balance, present at all steady swimming speeds, is probably due to the relatively uniform body shape of eels. As eels accelerate, thrust exceeds drag, axial momentum increases, and the wake approaches that of other fishes. During steady swimming, though, the lack of axial momentum prevents direct efficiency estimation. The effect of body shape was examined directly by measuring flow in multiple transverse planes along the body of bluegill sunfish swimming at 1.2 L s-1. The dorsal and anal fin, neglected in many previous studies of fish swimming, are shown to produce forces comparable to that of the caudal fin. Additionally, the caudal fin absorbs some of the energy from the vortices these fins shed, possibly augmenting its efficiency. Finally, an updated structure for the three-dimensional vortex wake of a sunfish is proposed.

Ingestion of soy-whey blended protein augments sports performance and ameliorates exercise-induced fatigue in a rat exercise model.

PubMed

Ren, Guangxu; Yi, Suqing; Zhang, Hongru; Wang, Jing

2017-02-22

This study sought to determine the effects of soy-whey blended protein supplementation on sports performance and related biochemical parameters after long-term training. After a week of adaptation, eighteen 6-week-old male Wistar rats were randomly assigned to 3 groups: the standard chow diet plus whey protein (Whey) group, the standard chow diet plus soy-whey blended protein (BP) group and the standard chow diet only (control) group. Each group included 6 rats for the seven-week experiment. Before the experiment, the baseline values of body weight, grasping force and time to exhaustion due to the loaded-swimming test were recorded for each group. During the experimental period, all rats performed the loaded-swimming test until exhaustion five days each week. The results showed that the mean maximum grasping force of the BP group significantly increased between the 5 th and the 7 th week (p < 0.05) compared with the other groups. The ingestion of blended protein for 7 weeks significantly increased the mean time to exhaustion due to swimming by 1.5-fold and 1.2-fold compared with the control and Whey groups, respectively. The plasma levels of leucine, isoleucine and valine were significantly higher at 60 min after the blended protein intervention compared with the Whey and control interventions (p < 0.05). Furthermore, the ingestion of soy-whey blended protein enhanced the activities of lactate dehydrogenase and superoxide dismutase and decreased the levels of malondialdehyde in serum. These results collectively suggest that soy-whey blended protein ingestion with resistance exercise can improve sports performance and ameliorate exercise-induced fatigue in rats.

Depression-related behavioural and neuroendocrine changes in the Spontaneously Diabetic Torii (SDT) fatty rat, an animal model of Type 2 Diabetes Mellitus.

PubMed

Sakimura, Katsuya; Maekawa, Tatsuya; Sasagawa, Kazuo; Ishii, Yukihito; Kume, Shin-Ichi; Ohta, Takeshi

2018-05-14

Depression is one of the most common psychiatric diseases and is commonly comorbid with type 1 or 2 diabetes mellitus (DM). However, the pathophysiology underlying the depressive state in DM remains poorly understood. Animal models are useful tools to investigate the association between depression and DM. In the present study we investigated whether the Spontaneously Diabetic Torii (SDT) fatty rat, a novel animal model of type 2 DM, shows depression-related features. We assessed depression-like behaviour, hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis, and neurotransmitter levels in the brain. Behaviour was evaluated using a forced swimming test, and the HPA axis was evaluated with changes in plasma corticosterone levels after a swimming stress exposure or dexamethasone challenge. In addition, serotonin (5-hydroxytryptamine; 5-HT), noradrenaline, glutamate and γ-aminobutyric acid (GABA) concentrations in the frontal cortex, hippocampus and brain stem were measured. In the forced swimming test, SDT fatty rats exhibited increased duration of immobility compared with control Sprague-Dawley (SD) rats. Moreover, basal corticosterone levels were significantly elevated in SDT fatty compared with control SD rats. However, there were no stress-induced increases or changes in dexamethasone-induced suppression of corticosterone in SDT fatty compared with control SD rats. Furthermore, there were significant changes in 5-HT concentrations in the prefrontal cortex, and in GABA and glutamate concentrations in the hippocampus in SDT fatty compared with controls. The results of the present study suggest that the SDT fatty rat may be an appropriate model for diabetes with comorbid depression associated with neurotransmitter impairments and aberrant basal HPA hyperactivity. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Psychostimulants and forced swim stress interaction: how activation of the hypothalamic-pituitary-adrenal axis and stress-induced hyperglycemia are affected.

PubMed

Gagliano, Humberto; Ortega-Sanchez, Juan Antonio; Nadal, Roser; Armario, Antonio

2017-10-01

We recently reported that simultaneous exposure to amphetamine and various stressors resulted in reduced hypothalamic-pituitary-adrenal (HPA) and glycemic responses to the stressors. Since this is a new and relevant phenomenon, we wanted to further explore this interaction. This study aims (i) to characterize the effect of various doses of amphetamine on the physiological response to a predominantly emotional stressor (forced swim) when the drug was given immediately before stress; (ii) to study if an interaction appears when the drug was given 30 min or 7 days before swim; and (iii) to know whether cocaine causes similar effects when given just before stress. Adult male rats were used and plasma levels of ACTH, corticosterone, and glucose were the outcomes. Amphetamine caused a dose-dependent activation of the HPA axis, but all doses reduced HPA and glycemic responses to swim when given just before the stressor. Importantly, during the post-swim period, the stressor potently inhibited the ACTH response to amphetamine, demonstrating mutual inhibition between the two stimuli. The highest dose of amphetamine also reduced the response to swim when given 30 min before stress, whereas it caused HPA sensitization when given 7 days before. Cocaine also reduced stress-induced HPA activation when given just before swim. The present results demonstrate a negative synergy between psychostimulants (amphetamine and cocaine) and stress regarding HPA and glucose responses when rats were exposed simultaneously to both stimuli. The inhibitory effect of amphetamine is also observed when given shortly before stress, but not some days before.

Inhibitory effects of forced swim stress and corticosterone on the acquisition but not expression of morphine-induced conditioned place preference: involvement of glucocorticoid receptor in the basolateral amygdala.

PubMed

Attarzadeh-Yazdi, Ghassem; Karimi, Sara; Azizi, Pegah; Yazdi-Ravandi, Saeid; Hesam, Soghra; Haghparast, Abbas

2013-09-01

Addiction is a common chronic psychiatric disease which represents a global problem and stress has an important role to increase drug addiction and relapse. In the present study, we investigated the effects of physical stress and exogenous corticosterone on the acquisition and expression of morphine-induced conditioned place preference (CPP). Also, we tried to find out the role of glucocorticoid receptors (GRs) of basolateral amygdala (BLA) in this regard. In the CPP paradigm, conditioning score and locomotion activity were recorded by Ethovision software. Male adult rats received forced swim stress (FSS) as a physical stress or corticosterone (10 mg/kg; ip) as a dominant stress hormone in rodents, 10min before morphine injection (5 mg/kg; sc) during three conditioning days (acquisition) or just prior to CPP test in the post-conditioning day (expression). In FSS procedure, animals were forced to swim for 6 min in cylinder filled with water (24-27 °C). To evaluate the role of glucocorticoid receptors in the BLA, different doses of mifepristone (RU38486) as a GR antagonist were injected into the BLA (0.3, 3 and 30 ng/side) during 3-day conditioning phase before FSS or injection of corticosterone in morphine-CPP paradigm. The results showed that FSS and corticosterone reduce the acquisition but not expression of morphine-induced CPP. Moreover, blockade of GRs in the BLA could diminish the inhibitory effects of FSS or corticosterone on the acquisition of morphine-induced CPP. It seems that stress exerts its effect on reward pathway via glucocorticoid receptors in the BLA. Copyright © 2013 Elsevier B.V. All rights reserved.

Evaluation of acute toxicity, sedative and analgesic effects of Taverniera glabra methanolic extract on mice.

PubMed

Marvi, -; Iqbal, Javeid; Muhammad, Shafi; Ahmad, Mansoor

2016-11-01

Present study was conducted on crude methanolic extract of stem and root of Taverniera glabra. In Pakistan T. glabra is found in the region of Balochistan only. T. glabra has numerous therapeutic uses in traditional medicine and it is also used for the pain relief. Current study was carried out to evaluate acute toxicity, analgesic and CNS depressant activity of the plant. Acute toxicity was carried out by oral administration of the T. glabra extract from 250 to 2000mg/kg oral dose. Analgesic activity was carried out by acetic acid induced writhing test and formalin test. Central Nervous System (CNS) depressant activity was carried out by exploratory activities (open field activity, cage crossing activity, rearing test) and forced swimming test. Oral administration of the methanolic extract of T. glabra was nontoxic at the dose of 1500mg/kg in the acute toxicity test. Exploratory behavior of mice treated with the methanolic extract of T. glabra showed sedative effects (P<0.05) in open field, cage crossing, traction and rearing test, particularly at the dose of 500mg as compared with standard drug Diazepam. In forced swimming test, mobility time was significantly (P<0.05) increased at 500mg/kg oral dose, and results were significant as compared with control. Methanolic extract of T. glabra produced significant (P<0.05) analgesic effects at the dose of 500mg/kg in the acetic acid induced writhing test and the formalin test. In conclusion, results show that the crude methanolic extract of T. glabra possess sedative as well as potent analgesic effects. Present pharmacological studies are the first ever studies conducted on the methanolic extract of T. glabra.

Magnolol abrogates chronic mild stress-induced depressive-like behaviors by inhibiting neuroinflammation and oxidative stress in the prefrontal cortex of mice.

PubMed

Cheng, Jie; Dong, Shuqi; Yi, Litao; Geng, Di; Liu, Qing

2018-06-01

Magnolol, the main constituent of Magnolia officinalis, has been shown to produce antidepressant-like effect in rodents. Growing evidence shows that neuroinflammation, oxidative stress and neuroendocrine contribute to the pathogenesis of major depression. Here, the aim of this present study was to determine whether magnolol affected these systems in mice exposed to chronic mild stress (CMS). The ameliorative effect of magnolol on depressive-like symptoms was investigated through behavioral tests, including the classical sucrose preference and forced swimming tests. The behavioral evaluation showed that magnolol reversed the depressive-like deficits both in sucrose preference test and forced swimming test. The elevation of prefrontal cortex pro-inflammatory cytokines such as interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) was decreased by magnolol. Consistently, the microglia activation by CMS was also alleviated by magnolol. In addition, the hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis induced by CMS was attenuated by magnolol. Moreover, the increased lipid peroxidation such as malonaldehyde (MDA) and decreased antioxidant defense enzymes including superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) induced by CMS were also reversed by magnolol. These findings suggest that administration of magnolol could alleviate depressive-like behaviors in CMS mice that are mediated by suppressing neuroinflammation and oxidative stress in the prefrontal cortex. Copyright © 2018 Elsevier B.V. All rights reserved.

Reduced emotional and corticosterone responses to stress in μ-opioid receptor knockout mice

PubMed Central

Ide, Soichiro; Sora, Ichiro; Ikeda, Kazutaka; Minami, Masabumi; Uhl, George R.; Ishihara, Kumatoshi

2014-01-01

The detailed mechanisms of emotional modulation in the nervous system by opioids remain to be elucidated, although the opioid system is well known to play important roles in the mechanisms of analgesia and drug dependence. In the present study, we conducted behavioral tests of anxiety and depression and measured corticosterone concentrations in both male and female μ-opioid receptor knockout (MOP-KO) mice to reveal the involvement of μ-opioid receptors in stress-induced emotional responses. MOP-KO mice entered more and spent more time in the open arms of the elevated plus maze compared with wild-type mice. MOP-KO mice also displayed significantly decreased immobility in a 15 min tail-suspension test compared with wild-type mice. Similarly, MOP-KO mice exhibited significantly decreased immobility on days 2, 3, and 4 in a 6 min forced swim test conducted for 5 consecutive days. The increase in plasma corticosterone concentration induced by tail-suspension, repeated forced swim, or restraint stress was reduced in MOP-KO mice compared with wild-type mice. Corticosterone levels were not different between wild-type and MOP-KO mice before stress exposure. In contrast, although female mice tended to exhibit fewer anxiety-like responses in the tail-suspension test in both genotypes, no significant gender differences were observed in stress-induced emotional responses. These results suggest that MOPs play an important facilitatory role in emotional responses to stress, including anxiety- and depression-like behavior and corticosterone levels. PMID:19596019

Can you really swim? Validation of self and parental reports of swim skill with an inwater swim test among children attending community pools in Washington State.

PubMed

Mercado, Melissa C; Quan, Linda; Bennett, Elizabeth; Gilchrist, Julie; Levy, Benjamin A; Robinson, Candice L; Wendorf, Kristen; Gangan Fife, Maria Aurora; Stevens, Mark R; Lee, Robin

2016-08-01

Drowning is the second leading cause of unintentional injury death among US children. Multiple studies describe decreased drowning risk among children possessing some swim skills. Current surveillance for this protective factor is self/proxy-reported swim skill rather than observed inwater performance; however, children's self-report or parents' proxy report of swim skill has not been validated. This is the first US study to evaluate whether children or parents can validly report a child's swim skill. It also explores which swim skill survey measure(s) correlate with children's inwater swim performance. For this cross-sectional convenience-based sample, pilot study, child/parent dyads (N=482) were recruited at three outdoor public pools in Washington State. Agreement between measures of self-reports and parental-reports of children's swim skill was assessed via paired analyses, and validated by inwater swim test results. Participants were representative of pool's patrons (ie, non-Hispanic White, highly educated, high income). There was agreement in child/parent dyads' reports of the following child swim skill measures: 'ever taken swim lessons', perceived 'good swim skills' and 'comfort in water over head'. Correlation analyses suggest that reported 'good swim skills' was the best survey measure to assess a child's swim skill-best if the parent was the informant (r=0.25-0.47). History of swim lessons was not significantly correlated with passing the swim test. Reported 'good swim skills' was most correlated with observed swim skill. Reporting 'yes' to 'ever taken swim lessons' did not correlate with swim skill. While non-generalisable, findings can help inform future studies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Antidepressant-like effects of erythropoietin: a focus on behavioural and hippocampal processes.

PubMed

Osborn, Meagan; Rustom, Nazneen; Clarke, Melanie; Litteljohn, Darcy; Rudyk, Chris; Anisman, Hymie; Hayley, Shawn

2013-01-01

Depression is a chronic and debilitating condition with a significant degree of relapse and treatment resistance that could stem, at least in part, from disturbances of neuroplasticity. This has led to an increased focus on treatment strategies that target brain derived neurotrophic factor (BDNF), synaptic plasticity and adult neurogenesis. In the current study we aimed to assess whether erythropoietin (EPO) would have antidepressant-like effects given its already established pro-trophic actions. In particular, we assessed whether EPO would diminish the deleterious effects of a social stressor in mice. Indeed, EPO induced anxiolytic and antidepressant-like responses in a forced swim test, open field, elevated-plus maze, and a novelty test, and appeared to blunt some of the negative behavioural effects of a social stressor. Furthermore, EPO promoted adult hippocampal neurogenesis, an important feature of effective antidepressants. Finally, a separate study using the mTOR inhibitor rapamycin revealed that antagonizing this pathway prevented the impact of EPO upon forced swim performance. These data are consistent with previous findings showing that the mTOR pathway and its neurogenic and synaptogenic effects might mediate the behavioral consequences of antidepressant agents. Our findings further highlight EPO as a possible adjunct treatment for affective disorders, as well as other stressor associated disorders of impaired neuroplasticity.

Concomitant administration of fluoxetine and amantadine modulates the activity of peritoneal macrophages of rats subjected to a forced swimming test.

PubMed

Roman, Adam; Rogóz, Zofia; Kubera, Marta; Nawrat, Dominika; Nalepa, Irena

2009-01-01

Recent studies show that administration of a non-competitive NMDA receptor antagonist, amantadine (AMA), potentiates the action of antidepressant drugs. Since antidepressants may modulate functioning of the immune system and activation of a pro-inflammatory response in depressive disorders is frequently reported, the aim of the present study was to examine whether a combined administration of AMA and the antidepressant, fluoxetine (FLU), to rats subsequently subjected to a forced swimming test (FST) modifies the parameters of macrophage activity, directly related to their immunomodulatory functions, i.e., arginase (ARG) activity and synthesis of nitric oxide (NO). We found that 10 mg/kg AMA and 10 mg/kg FLU, ineffective in FST for antidepressant-like activity when administered alone, increased the ARG/NO ratio in macrophages when administered concomitantly. This effect was accompanied by a decrease of cellular adherence. Concurrently, the basal metabolic activity of the cells measured with reduction of resazurin, and intracellular host defense as assessed by a synthesis of superoxide anion, were not affected by such antidepressive treatment. Our data indicate that co-administration of AMA and FLU decreases the pro-inflammatory properties of macrophages and causes a redirection of immune response toward anti-inflammatory activity, as one can anticipate in the case of an effective antidepressive treatment.

Attenuation of acute restraint stress-induced depressive like behavior and hippocampal alterations with protocatechuic acid treatment in mice.

PubMed

Thakare, Vishnu N; Dhakane, Valmik D; Patel, Bhoomika M

2017-04-01

Protocatechuic acid ethyl ester (PCA), a phenolic compound, exhibits neuroprotective effects through improving endogenous antioxidant enzymatic and nonezymatic system. Based on the role of oxidative stress in modulating depressive disorders and the relationship between neuroprotective and antioxidant potential of PCA, we studied if its antidepressant like effect is associated by modulation of cerebral cortex and hippocampal antioxidant alterations. Acute restraint stress (ARS) is known to induce depressive like behavior by neuronal oxidative damage in mice. Swiss albino mice subjected to ARS exhibited an increased immobility time in forced swim test, elevated serum corticosterone and produced oxidative stress dependent alterations in cerebral cortex and hippocampus mainly increased thiobarbituric acid reactive substances and reduced catalase (CAT), superoxide dismutase (SOD) activity. Treatment with PCA was able to prevent stress induced immobility time in forced swim test without altering locomotor activity in mice. Further, PCA treatment attenuated the elevation of serum corticosterone, lipid peroxidation and restored enzymatic antioxidants in cerebral cortex and hippocampus in ARS mice. Altogether, the experimental findings demonstrate the notion that PCA exhibit antidepressant like activity might be related, at least in part, to its capability of modulating antioxidant defense system and oxidative damage induced by ARS in cerebral cortex and hippocampus in mice and thus maintain the pro-/anti-oxidative homeostasis.

Stress-induced anhedonia in mice is associated with deficits in forced swimming and exploration.

PubMed

Strekalova, Tatyana; Spanagel, Rainer; Bartsch, Dusan; Henn, Fritz A; Gass, Peter

2004-11-01

In order to develop a model for a depression-like syndrome in mice, we subjected male C57BL/6 mice to a 4-week-long chronic stress procedure, consisting of rat exposure, restraint stress, and tail suspension. This protocol resulted in a strong decrease in sucrose preference, a putative indicator of anhedonia in rodents. Interestingly, predisposition for stress-induced anhedonia was indicated by submissive behavior in a resident-intruder test. In contrast, most mice with nonsubmissive behavior did not develop a decrease in sucrose preference and were regarded as nonanhedonic. These animals were used as an internal control for stress-induced behavioral features not associated with the anhedonic state, since they were exposed to the same stressors as the anhedonic mice. Using a battery of behavioral tests after termination of the stress procedure, we found that anhedonia, but not chronic stress per se, is associated with key analogues of depressive symptoms, such as increased floating during forced swimming and decreased exploration of novelty. On the other hand, increased anxiety, altered locomotor activity, and loss of body weight were consequences of chronic stress, which occurred independently from anhedonia. Thus, behavioral correlates of stress-induced anhedonia and of chronic stress alone can be separated in the present model.

Protein and lipid oxidative damage in streptozotocin-induced diabetic rats submitted to forced swimming test: the insulin and clonazepam effect.

PubMed

Wayhs, Carlos Alberto Yasin; Manfredini, Vanusa; Sitta, Angela; Deon, Marion; Ribas, Graziela; Vanzin, Camila; Biancini, Giovana; Ferri, Marcelo; Nin, Maurício; Barros, Helena Maria Tannhauser; Vargas, Carmen Regla

2010-09-01

Diabetes may modify central nervous system functions and is associated with moderate cognitive deficits and changes in the brain, a condition that may be referred to as diabetic encephalopathy. The prevalence of depression in diabetic patients is higher than in the general population, and clonazepam is being used to treat this complication. Oxidative stress may play a role in the development of diabetes complications. We investigated oxidative stress parameters in streptozotocin-induced diabetic rats submitted to forced swimming test (STZ) and evaluated the effect of insulin (STZ-INS) and/or clonazepam (STZ-CNZ and STZ-INS-CNZ) acute treatment on these animal model. Oxidative damage to proteins measured as carbonyl content in plasma was significantly increased in STZ group compared to STZ treated groups. Malondialdehyde plasma levels were significantly reduced in STZ-INS and STZ-INS-CNZ groups when compared to STZ rats, being significantly reduced in STZ-INS-CNZ than STZ-INS rats. The activities of the antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase showed no significant differences among all groups of animals. These findings showed that protein and lipid damage occurs in this diabetes/depression animal model and that the associated treatment of insulin and clonazepam is capable to protect against oxidative damage in this experimental model.

Brain effect of insulin and clonazepam in diabetic rats under depressive-like behavior.

PubMed

Wayhs, Carlos Alberto Yasin; Mescka, Caroline Paula; Vanzin, Camila Simioni; Ribas, Graziela Schmitt; Guerreiro, Gilian; Nin, Maurício Schüler; Manfredini, Vanusa; Barros, Helena Maria Tannhauser; Vargas, Carmen Regla

2013-12-01

Diabetes mellitus is characterized by hyperglycemia resulting from defects on insulin secretion, insulin action, or both. It has recently become clear that the central nervous system is not spared from the deleterious effects of diabetes, since diabetic encephalopathy was recognized as a complication of this heterogeneous metabolic disorder. There is a well recognized association between depression and diabetes, once prevalence of depression in diabetic patients is higher than in general population, and clonazepam is being used to treat this complication. Oxidative stress is widely accepted as playing a key mediatory role in the development and progression of diabetes and its complications. In this work we analyzed DNA damage by comet assay and lipid damage in prefrontal cortex, hippocampus and striatum of streptozotocin-induced diabetic rats submitted to the forced swimming test. It was verified that the diabetic group presented DNA and lipid damage in the brain areas evaluated, when compared to the control groups. Additionally, a significant reduction of the DNA and lipid damage in animals treated with insulin and/or clonazepam was observed. These data suggest that the association of these two drugs could protect against DNA and lipid damage in diabetic rats submitted to the forced swimming test, an animal model of depression.

Diabetic encephalopathy-related depression: experimental evidence that insulin and clonazepam restore antioxidant status in rat brain.

PubMed

Wayhs, Carlos Alberto Yasin; Mescka, Caroline Paula; Guerreiro, Gilian; Moraes, Tarsila Barros; Jacques, Carlos Eduardo Diaz; Rosa, Andrea Pereira; Ferri, Marcelo Kneib; Nin, Maurício Schüler; Dutra-Filho, Carlos Severo; Barros, Helena Maria Tannhauser; Vargas, Carmen Regla

2014-12-01

There is increasing evidence suggesting that oxidative stress plays an important role in the development of many chronic and degenerative conditions such as diabetic encephalopathy and depression. Considering that diabetic rats and mice present higher depressive-like behaviour when submitted to the forced swimming test and that treatment with insulin and/or clonazepam is able to reverse the behavioural changes of the diabetic rats, the present work investigated the antioxidant status, specifically total antioxidant reactivity and antioxidant potential of insulin and clonazepam, as well as the effect of this drugs upon protein oxidative damage and reactive species formation in cortex, hippocampus and striatum from diabetic rats submitted to forced swimming test. It was verified that longer immobility time in diabetic rats and insulin plus clonazepam treatment reversed this depressive-like behaviour. Moreover, data obtained in this study allowed to demonstrate through different parameters such as protein carbonyl content, 2'7'-dichlorofluorescein oxidation, catalase, superoxide dismutase, glutathione peroxidase assay, total radical-trapping antioxidant potential and total antioxidant reactivity that there is oxidative stress in cortex, hippocampus and striatum from diabetic rats under depressive-like behaviour and highlight the insulin and/or clonazepam effect in these different brain areas, restoring antioxidant status and protein damage. Copyright © 2014 John Wiley & Sons, Ltd.

Effects of nutritional status on metabolic rate, exercise and recovery in a freshwater fish.

PubMed

Gingerich, Andrew James; Philipp, David P; Suski, Cory D

2010-03-01

The influence of feeding on swimming performance and exercise recovery in fish is poorly understood. Examining swimming behavior and physiological status following periods of feeding and fasting is important because wild fish often face periods of starvation. In the current study, researchers force fed and fasted groups of largemouth bass (Micropterus salmoides) of similar sizes for a period of 16 days. Following this feeding and fasting period, fish were exercised for 60 s and monitored for swimming performance and physiological recovery. Resting metabolic rates were also determined. Fasted fish lost an average of 16 g (nearly 12%) of body mass, while force fed fish maintained body mass. Force fed fish swam 28% further and required nearly 14 s longer to tire during exercise. However, only some physiological conditions differed between feeding groups. Resting muscle glycogen concentrations was twofold greater in force fed fish, at rest and throughout recovery, although it decreased in both feeding treatments following exercise. Liver mass was nearly three times greater in force fed fish, and fasted fish had an average of 65% more cortisol throughout recovery. Similar recovery rates of most physiological responses were observed despite force fed fish having a metabolic rate 75% greater than fasted fish. Results are discussed as they relate to largemouth bass starvation in wild systems and how these physiological differences might be important in an evolutionary context.

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

Gingerich, Andrew J.; Philipp, D. P.; Suski, C. D.

The influence of feeding on swimming performance and exercise recovery in fish is poorly understood. Examining swimming behavior and physiological status following periods of feeding and fasting is important because wild fish often face periods of starvation. In the current study, researchers force fed and fasted groups of largemouth bass (Micropterus salmoides) of similar sizes for a period of 16 days. Following this feeding and fasting period, fish were exercised for 60 s and monitored for swimming performance and physiological recovery. Resting metabolic rates were also determined. Fasted fish lost an average of 16 g (nearly 12%) of body mass,more » while force fed fish maintained body mass. Force fed fish swam 28% further and required nearly 14 s longer to tire during exercise. However, only some physiological conditions differed between feeding groups. Resting muscle glycogen concentrations was twofold greater in force fed fish, at rest and throughout recovery, although it decreased in both feeding treatments following exercise. Liver mass was nearly three times greater in force fed fish, and fasted fish had an average of 65% more cortisol throughout recovery. Similar recovery rates of most physiological responses were observed despite force fed fish having a metabolic rate 75% greater than fasted fish. Results are discussed as they relate to largemouth bass starvation in wild systems and how these physiological differences might be important in an evolutionary context.« less

Relationship between isometric shoulder strength and arms-only swimming power among male collegiate swimmers: study of valid clinical assessment methods.

PubMed

Awatani, Takenori; Morikita, Ikuhiro; Mori, Seigo; Shinohara, Junji; Tatsumi, Yasutaka

2018-04-01

[Purpose] The purpose of the present study was to confirm the relationships between shoulder strength (extensor strength and internal rotator strength) of the abducted position and swimming power during arm-only swimming. [Subjects and Methods] Fourteen healthy male collegiate swimmers participated in the study. Main measures were shoulder strength (strength using torque that was calculated from the upper extremity length and the isometric force of the abducted position) and swimming power. [Results] Internal rotation torque of the dominant side in the abducted external rotated position (r=0.85) was significantly correlated with maximum swimming power. The rate of bilateral difference in extension torque in the maximum abducted position (r=-0.728) was significantly correlated with the swimming velocity-to-swimming power ratio. [Conclusion] The results of this study suggest that internal rotator strength measurement in the abducted external rotated position and extensor strength measurement in the maximum abducted position are valid assessment methods for swimmers.

Three-dimensional flow about penguin wings

NASA Astrophysics Data System (ADS)

Noca, Flavio; Sudki, Bassem; Lauria, Michel

2012-11-01

Penguins, contrary to airborne birds, do not need to compensate for gravity. Yet, the kinematics of their wings is highly three-dimensional and seems exceedingly complex for plain swimming. Is such kinematics the result of an evolutionary optimization or is it just a forced adaptation of an airborne flying apparatus to underwater swimming? Some answers will be provided based on flow dynamics around robotic penguin wings. Updates will also be presented on the development of a novel robotic arm intended to simulate penguin swimming and enable novel propulsion devices.

Prey capture by freely swimming flagellates

NASA Astrophysics Data System (ADS)

Andersen, Anders; Dolger, Julia; Nielsen, Lasse Tor; Kiorboe, Thomas

2017-11-01

Flagellates are unicellular microswimmers that propel themselves using one or several beating flagella. Here, we explore the dependence of swimming kinematics and prey clearance rate on flagellar arrangement and determine optimal flagellar arrangements and essential trade-offs. To describe near-cell flows around freely swimming flagellates we consider a model in which the cell is represented by a no-slip sphere and each flagellum by a point force. For uniflagellates pulled by a single flagellum the model suggests that a long flagellum favors fast swimming, whereas high clearance rate is favored by a very short flagellum. For biflagellates with both a longitudinal and a transversal flagellum we explore the helical swimming kinematics and the prey capture sites. We compare our predictions with observations of swimming kinematics, prey capture, and flows around common marine flagellates. The Centre for Ocean Life is a VKR Centre of Excellence supported by the Villum Foundation.

Flavonoid-rich fraction of the Monodora tenuifolia seed extract attenuates behavioural alterations and oxidative damage in forced-swim stressed rats.

PubMed

Ekeanyanwu, Raphael Chukwuma; Njoku, Obioma Uzoma

2015-03-01

The antidepressant effects of the flavonoid-rich fraction of Monodora tenuifolia seed extract were examined by assessing the extent of attenuation of behavioural alterations and oxidative damage in the rats that were stressed by forced swim test. Compared with the model control group, the altered behavioural parameters were attenuated significantly (P < 0.05) in the group treated with the flavonoid-rich fraction (100 and 200 mg·kg(-1)), comparable to the group treated with the standard drug, fluoxetine (10 mg·kg(-1)). The flavonoid-rich fraction and fluoxetine improved significantly (P < 0.05) the activities of the antioxidant enzymes such as superoxide dismutase and catalase as well as other biochemical parameters such as reduced glutathione, protein, and nitrite in the brain of the stressed rats. These results suggested that the flavonoid-rich fraction of Monodora tenuifolia seed extract exerted the antidepressant-like effects which could be useful in the management of stress induced disease. Copyright © 2015 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

Maternal separation increases later immobility during forced swim in guinea pig pups: evidence for sensitization of a depressive-like state.

PubMed

Hennessy, Michael B; Schreibeis, Amanda D; Schiml, Patricia A; Deak, Terrence

2017-01-01

Early-life stress is thought to increase later vulnerability for developing depressive illness by sensitizing underlying stress-responsive systems. Guinea pig pups separated from their mother and isolated in a novel cage for 3 hr exhibit a sensitized depressive-like behavioral response when separated again the following day as well as weeks later. The behavioral response and its sensitization appear to be mediated by inflammatory factors. To determine if this sensitization is specific to the separation response or if it reflects a broader underlying depressive-like state, guinea pig pups that had either been separated for 3 hr or remained with their mothers were observed in the forced swim test the following 3 days. Earlier separation was found to increase the duration of immobility, a measure sensitive to antidepressant treatment. These results support the use of the guinea pig as a model for examining mechanisms of inflammatory-mediated sensitization of depression following stress in early life. © 2016 Wiley Periodicals, Inc.

[Analysis of the swimming pattern and the velocity of bacteria using video tracking method].

PubMed

Shigematsu, M

1997-04-01

The swimming patterns and the velocities of several flagellated bacteria were measured by a computer assisted video tracking method. The moving path of the individual bacterium revealed that the bacterium frequently changed its swimming direction and velocity. The velocity among bacterial strains varies widely. In low viscous environment. Campylobacter jejuni has characteristic swimming pattern with frequent changes in their swimming direction. As the viscosity increase, C. jejuni increases its velocity at a little higher viscosity of 3 centipoise (cP) and secondly increases at about 40 cP. Different from other flagellated bacteria, the swimming pattern of C. jejuni in these two velocity peaks were changed. C. jejuni exhibited continuously forward moving path in the first peak, but in the second it repeated back and forth swimming pattern. We thus assumed that C. jejuni may use a different swimming mode in high viscous media from the original mode mediated by the propelling force of the flagella. This method is useful for a detail analysis of bacterial movement and moving patterns in different environmental conditions.

Effects of 4-hydroxyisoleucine from Fenugreek Seeds on Depression-like Behavior in Socially Isolated Olfactory Bulbectomized Rats.

PubMed

Kalshetti, Padmaja B; Alluri, Ramesh; Mohan, Vishwaraman; Thakurdesai, Prasad Arvind

2015-10-01

Antidepressant-like effects of (2S, 3R, 4S)-4-hydroxyisoleucine (4-HI), a major amino acid from fenugreek seeds, has been reported in the animal model of acute depression. To evaluate effects of subacute administration of 4-HI in animal model of stress-induced depression namely socially isolated olfactory bulbectomized rats. Bilateral olfactory bulbectomy (OBX) were induced in 30 Sprague-Dawley rats. After recovery period of 14 days, rats were randomized into five groups of 6 rats each and stressed with social isolation (individual housing). The rats were orally treated with either vehicle (OBX-Iso), positive control, fluoxetine (30 mg/kg) or 4-HI (10, 30, 100 mg/kg) once a day from day 14 onward. Separate group of rats with social isolation but without OBX (Sham-Iso) was also maintained. The behavioral depression and anxiety related parameters using open field test (OFT), sucrose intake test, novelty suppressed feeding (NSF) and forced swim test (FST), and neurochemical estimation (brain monoamines viz., serotonin and nor-adrenaline, serotonin turnover, and serum cortisol) were performed. Data was analyzed by either two-way ANOVA (OFT and FST) or one-way ANOVA (sucrose intake test, NSF, and neurochemical estimation) followed by Dunnett's multiple comparisons test. Differences were considered significant at P < 0.05. The significant and dose-dependent protection from behavioral and neurochemical changes were observed in 4-HI co-administrated OBX-Iso rats. 4-HI demonstrated the antidepressant and antianxiety effects in socially isolated stress-induced OBX rats with possible involvement of multiple stress relieving mechanisms. In this study, the subacute pretreatment of 4-HI showed strong and dose-dependent prevention of isolation stress related behavioral and neurochemical responses in olfactory bulbectomized rats. The prevention of hyperactive HPA axis in OBX-Iso stress-induced rats can be envisaged as probable mechanism of antidepressant and antianxiety effects of 4-HI. Effect of 4-hydroxyisoleucine (4-HI) in olfactory bulbectomized and socially isolated (Iso) rats was evaluated4-HI showed significant and dose-dependent antidepressant effects during novelty suppressed feeding (NSF) and forced swim test (FST)4-HI showed significant and dose-dependent antianxiety effects during OFT (open field test) and sucrose intake test4-HI showed protection from OBX-Iso stress-induced brain monoamines, serotonin turnover, and serum cortisol level elevation. Abbreviations used: SSRI: Selective Serotonin Reuptake Inhibitor; 4-HI: (2S, 3R, 4S)-4-hydroxyisoleucine; OBX: Olfactory bulbectomy; CPCSEA: Committee for the Purpose of Control and Supervision of Experiments on Animals; OFT: Open Field Test; NSF: Novelty Suppressed Feeding; FST: Forced Swimming Test; 5HT: 5-Hydroxytryptamine; 5-HIAA: 5-Hydroxyindoleacetic Acid; NA: Nor-adrenaline; and HPA: Hypothalamic-Pituitary Adrenal.

Free swimming organisms: Microgravity as an investigative tool

NASA Technical Reports Server (NTRS)

Kessler, John O.

1989-01-01

On earth, micro-organisms are in the grip of gravitational and viscous forces. These forces, in combination with sensory stimuli, determine the average orientation of the organisms' swimming trajectories relative to the fluid environment. Microgravity provides the opportunity to study the rules which govern the summation or orienting influences and to develop quantitative physical measurements of sensory responses, e.g. the measurement of phototactic orientation tendency in torque units. Also, by reducing or eliminating density anisotropy-driven buoyant convection, it will be possible to study illumination, temperature gradient and concentration gradient-mediated collective dynamics.

Flow-induced attraction of swimming microorganisms by surfaces

NASA Astrophysics Data System (ADS)

Lauga, Eric; Berke, Allison; Turner, Linda; Berg, Howard

2008-03-01

In this talk, we present an experimental and theoretical investigation of the accumulation of swimming cells by nearby surfaces. First, we present results of an experiment aiming at measuring the distribution of smooth-swimming E. coli when moving in a density-matched fluid and between two glass plates; the distribution for the bacteria concentration is found to peak near the glass plates. We then present a physical model for the observed attraction, based on the hydrodynamics interactions between the swimming cells and the walls. We show that such interactions result in a reorientation of the cells in the direction parallel to the surfaces, and an attraction of these (parallel) cells by the nearest wall. Our results are exploited to obtain an estimate of the propulsive force of smooth-swimming E. coli.

Learning and memory in the forced swimming test: effects of antidepressants having varying degrees of anticholinergic activity.

PubMed

Enginar, Nurhan; Yamantürk-Çelik, Pınar; Nurten, Asiye; Güney, Dilvin Berrak

2016-07-01

The antidepressant-induced reduction in immobility time in the forced swimming test may depend on memory impairment due to the drug's anticholinergic efficacy. Therefore, the present study evaluated learning and memory of the immobility response in rats after the pretest and test administrations of antidepressants having potent, comparatively lower, and no anticholinergic activities. Immobility was measured in the test session performed 24 h after the pretest session. Scopolamine and MK-801, which are agents that have memory impairing effects, were used as reference drugs for a better evaluation of the memory processes in the test. The pretest administrations of imipramine (15 and 30 mg/kg), amitriptyline (7.5 and 15 mg/kg), trazodone (10 mg/kg), fluoxetine (10 and 20 mg/kg), and moclobemide (10 and 20 mg/kg) were ineffective, whereas the pretest administrations of scopolamine (0.5 mg/kg) and MK-801 (0.1 mg/kg) decreased immobility time suggesting impaired "learning to be immobile" in the animals. The test administrations of imipramine (30 mg/kg), amitriptyline (15 mg/kg), moclobemide (10 mg/kg), scopolamine (0.5 and 1 mg/kg), and MK-801 (0.1 mg/kg) decreased immobility time, which suggested that the drugs exerted antidepressant activity or the animals did not recall that attempting to escape was futile. The test administrations of trazodone (10 mg/kg) and fluoxetine (10 and 20 mg/kg) produced no effect on immobility time. Even though the false-negative and positive responses made it somewhat difficult to interpret the findings, this study demonstrated that when given before the pretest antidepressants with or without anticholinergic activity seemed to be devoid of impairing the learning process in the test.

Can Blood Gas and Acid-Base Parameters at Maximal 200 Meters Front Crawl Swimming be Different Between Former Competitive and Recreational Swimmers?

PubMed Central

Kapus, Jernej; Usaj, Anton; Strumbelj, Boro; Kapus, Venceslav

2008-01-01

The aim of the present study was to ascertain whether maximal 200 m front crawl swimming strategies and breathing patterns influenced blood gas and acid-base parameters in a manner which gives advantage to former competitive swimmers in comparison with their recreational colleagues. Twelve former competitive male swimmers (the CS group) and nine recreational male swimmers (the RS group) performed a maximal 200 m front crawl swimming with self- selected breathing pattern. Stroke rate (SR) and breathing frequency (BF) were measured during the swimming test. Measures also included blood lactate concentration ([LA]) and parameters of blood acid-base status before and during the first minute after the swimming test. The CS group swam faster then the RS group. Both groups have similar and steady SR throughout the swimming test. This was not matched by similar BF in the CS group but matched it very well in the RS group (r = 0.89). At the beginning of swimming test the CS group had low BF, but they increased it throughout the swimming test. The BF at the RS group remained constant with only mirror variations throughout the swimming test. Such difference in velocity and breathing resulted in maintaining of blood Po2 from hypoxia and Pco2 from hypercapnia. This was similar in both groups. [LA] increased faster in the CS group than in the RS group. On the contrary, the rate of pH decrease remained similar in both groups. The former competitive swimmers showed three possible advantages in comparison to recreational swimmers during maximal 200 m front crawl swimming: a more dynamic and precise regulation of breathing, more powerful bicarbonate buffering system and better synchronization between breathing needs and breathing response during swimming. Key pointsTraining programs for competitive swimmers should promote adaptations to maximal efforts.Those adaptations should include high and maximal intensity swims with controlled breathing frequency (taking breath every fourth, fifth, sixth or eighth stroke cycle for front crawl swimming).Such training will improve breathing regulation in order to impose a better synchronization between breathing needs and breathing response during maximal swimming. PMID:24150142

Omega-3 Fatty Acid Deficient Male Rats Exhibit Abnormal Behavioral Activation in the Forced Swim Test Following Chronic Fluoxetine Treatment: Association with Altered 5-HT1A and Alpha2A Adrenergic Receptor Expression

PubMed Central

Able, Jessica A.; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; McNamara, Robert K.

2014-01-01

Omega-3 fatty acid deficiency during development leads to enduing alterations in central monoamine neurotransmission in rat brain. Here we investigated the effects of omega-3 fatty acid deficiency on behavioral and neurochemical responses to chronic fluoxetine (FLX) treatment. Male rats were fed diets with (CON, n=34) or without (DEF, n=30) the omega-3 fatty acid precursor alpha-linolenic acid (ALA) during peri-adolescent development (P21-P90). A subset of CON (n=14) and DEF (n=12) rats were administered FLX (10 mg/kg/d) through their drinking water for 30 d beginning on P60. The forced swimming test (FST) was initiated on P90, and regional brain mRNA markers of serotonin and noradrenaline neurotransmission were determined. Dietary ALA depletion led to significant reductions in frontal cortex docosahexaenoic acid (DHA, 22:6n-3) composition in DEF (−26%, p=0.0001) and DEF+FLX (−32%, p=0.0001) rats. Plasma FLX and norfluoxetine concentrations did not different between FLX-treated DEF and CON rats. During the 15-min FST pretest, DEF+FLX rats exhibited significantly greater climbing behavior compared with CON+FLX rats. During the 5-min test trial, FLX treatment reduced immobility and increased swimming in CON and DEF rats, and only DEF+FLX rats exhibited significant elevations in climbing behavior. DEF+FLX rats exhibited greater midbrain, and lower frontal cortex, 5-HT1A mRNA expression compared with all groups including CON+FLX rats. DEF+FLX rats also exhibited greater midbrain alpha2A adrenergic receptor mRNA expression which was positively correlated with climbing behavior in the FST. These preclinical data demonstrate that low omega-3 fatty acid status leads to abnormal behavioral and neurochemical responses to chronic FLX treatment in male rats. PMID:24360505

Swimming efficiency of bacterium Escherichia coli

PubMed Central

Chattopadhyay, Suddhashil; Moldovan, Radu; Yeung, Chuck; Wu, X. L.

2006-01-01

We use measurements of swimming bacteria in an optical trap to determine fundamental properties of bacterial propulsion. In particular, we directly measure the force required to hold the bacterium in the optical trap and determine the propulsion matrix, which relates the translational and angular velocity of the flagellum to the torques and forces propelling the bacterium. From the propulsion matrix, dynamical properties such as torques, swimming speed, and power can be obtained by measuring the angular velocity of the motor. We find significant heterogeneities among different individuals even though all bacteria started from a single colony. The propulsive efficiency, defined as the ratio of the propulsive power output to the rotary power input provided by the motors, is found to be ≈2%, which is consistent with the efficiency predicted theoretically for a rigid helical coil. PMID:16954194

Swimming Back and Forth Using Planar Flagellar Propulsion at Low Reynolds Numbers.

PubMed

Khalil, Islam S M; Tabak, Ahmet Fatih; Hamed, Youssef; Mitwally, Mohamed E; Tawakol, Mohamed; Klingner, Anke; Sitti, Metin

2018-02-01

Peritrichously flagellated Escherichia coli swim back and forth by wrapping their flagella together in a helical bundle. However, other monotrichous bacteria cannot swim back and forth with a single flagellum and planar wave propagation. Quantifying this observation, a magnetically driven soft two-tailed microrobot capable of reversing its swimming direction without making a U-turn trajectory or actively modifying the direction of wave propagation is designed and developed. The microrobot contains magnetic microparticles within the polymer matrix of its head and consists of two collinear, unequal, and opposite ultrathin tails. It is driven and steered using a uniform magnetic field along the direction of motion with a sinusoidally varying orthogonal component. Distinct reversal frequencies that enable selective and independent excitation of the first or the second tail of the microrobot based on their tail length ratio are found. While the first tail provides a propulsive force below one of the reversal frequencies, the second is almost passive, and the net propulsive force achieves flagellated motion along one direction. On the other hand, the second tail achieves flagellated propulsion along the opposite direction above the reversal frequency.

Flying fish accelerate at 5 G to leap from the water surface

NASA Astrophysics Data System (ADS)

Yang, Patricia; Phonekeo, Sulisay; Xu, Ke; Chang, Shui-Kai; Hu, David

2013-11-01

Flying fish can both swim underwater and glide in air. Transitioning from swimming to gliding requires penetration of the air-water interface, or breaking the ``surface tension barrier,'' a formidable task for juvenile flying fish measuring 1 to 5 cm in length. In this experimental investigation, we use high-speed videography to characterize the kinematics of juvenile flying fish as they leap from the water surface. During this process, which lasts 0.05 seconds, flying fish achieve body accelerations of 5 times earth's gravity and gliding speeds of 1.3 m/s, an order of magnitude higher than their steady swimming speed. We rationalize this anomalously high speed on the basis of the hydrodynamic and surface tension forces and torques experienced by the fish. Specifically, leaping fish experience skin friction forces only on the submerged part of their body, permitting them to achieve much higher speeds than in steady underwater swimming. We also perform experiments using a towed flying fish mimc to determine optimality of various parameters in this process, including body angle and start position with respect to the water surface.

Quiet swimming at low Reynolds number

NASA Astrophysics Data System (ADS)

Andersen, Anders; Wadhwa, Navish; Kiørboe, Thomas

2015-04-01

The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturbance described by a force quadrupole that decays as one over distance cubed. Motivated by recent experimental results on fluid disturbances due to small aquatic organisms, we demonstrate that a three-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws are valid surprisingly close to the organism. Finally, we discuss point force models as a general framework for hypothesis generation and experimental exploration of fluid mediated predator-prey interactions in the planktonic world.

Quiet swimming at low Reynolds number.

PubMed

Andersen, Anders; Wadhwa, Navish; Kiørboe, Thomas

2015-04-01

The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode that eliminates the stresslet component of the flow and leads to a faster spatial decay of the fluid disturbance described by a force quadrupole that decays as one over distance cubed. Motivated by recent experimental results on fluid disturbances due to small aquatic organisms, we demonstrate that a three-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws are valid surprisingly close to the organism. Finally, we discuss point force models as a general framework for hypothesis generation and experimental exploration of fluid mediated predator-prey interactions in the planktonic world.

A numerical study of the benefits of driving jellyfish bells at their natural frequency.

PubMed

Hoover, Alexander; Miller, Laura

2015-06-07

A current question in swimming and flight is whether or not driving flexible appendages at their resonant frequency results in faster or more efficient locomotion. It has been suggested that jellyfish swim faster when the bell is driven at its resonant frequency. The goal of this study was to determine whether or not driving a jellyfish bell at its resonant frequency results in a significant increase in swimming velocity. To address this question, the immersed boundary method was used to solve the fully coupled fluid structure interaction problem of a flexible bell in a viscous fluid. Free vibration numerical experiments were used to determine the resonant frequency of the jellyfish bell. The jellyfish bells were then driven at frequencies ranging from above and below the resonant frequency. We found that jellyfish do swim fastest for a given amount of applied force when the bells are driven near their resonant frequency. Nonlinear effects were observed for larger deformations, shifting the optimal frequency to higher than the resonant frequency. We also found that the benefit of resonant forcing decreases for lower Reynolds numbers. Published by Elsevier Ltd.

Scaling the Thrust Production and Energetics of Inviscid Intermittent Swimming

NASA Astrophysics Data System (ADS)

Akoz, Emre; Moored, Keith

2015-11-01

Many fish have adopted an intermittent swimming gait sometimes referred as a burst-and-coast behavior. By using this gait, fish have been estimated at reducing their energetic cost of swimming by about 50%. Lighthill proposed that the skin friction drag of an undulating body can be around 400% greater than a rigidly-held coasting body, which may explain the energetic savings of intermittent swimming. Recent studies have confirmed the increase in skin friction drag over an undulating body, however, the increase is on the order of 20-70%. This more modest gain in skin friction drag is not sufficient to lead to the observed energy savings. Motivated by these observations, we investigate the inviscid mechanisms behind intermittent swimming for parameters typical of biology. We see that there is an energy savings at a fixed swimming speed for intermittent swimming as compared to continuous swimming. Then we consider three questions: What is the nature of the inviscid mechanism that leads to the observed energy savings, how do the forces and energetics of intermittent swimming scale with the swimming parameters, and what are the limitations to the benefit? Supported by the Office of Naval Research under Program Director Dr. Bob Brizzola, MURI grant number N00014-14-1-0533.

Antidepressant-like activity of anthocyanidins from Hibiscus rosa-sinensis flowers in tail suspension test and forced swim test

PubMed Central

Shewale, Pallavi B.; Patil, Rupali A.; Hiray, Yogesh A.

2012-01-01

Aim: Flowers of Hibiscus rosa-sinensis Linn (Malvaceae) popularly known as “China-rose flowers” contain flavonoids. Flavonoids have been found to have antidepressant activity. The aim of the present study is to evaluate the antidepressant activity of flavonoids in H. rosa-sinensis flowers with possible involvement of monoamines. Materials and Methods: Anti-depressant activity of methanol extract containing anthocyanins (MHR) (30 and 100 mg/kg) and anthocyanidins (AHR) (30 and 100 mg/ kg) of H. rosa-sinensis flowers were evaluated in mice using behavioral tests such as tail suspension test (TST) and forced swim test (FST). The mechanism of action involved in antidepressant activity was investigated by observing the effect of extract after pre-treatment with low dose haloperidol, prazosin and para-chlorophenylalanine (p-CPA). Results: Present study exhibited significant decrease in immobility time in TST and FST, similar to that of imipramine (10 mg/kg, i.p.) which served as a positive control. The extract significantly attenuated the duration of immobility induced by Haloperidol (50 μg/ kg, i.p., a classical D2-like dopamine receptor antagonist), Prazosin (62.5 μg/kg, i.p., an α1-adrenoceptor antagonist) and p-chlorophenylalanine (100 mg/kg, i.p., × 3 days; an inhibitor of serotonin synthesis) in both TST and FST. Conclusion: It can be concluded that MHR and AHR possess potential antidepressant activity (through dopaminergic, noradrenergic and serotonergic mechanisms) and has therapeutic potential in the treatment of CNS disorders and provides evidence at least at preclinical levels. PMID:23087504

Inhibition of the CRF1 receptor influences the activity of antidepressant drugs in the forced swim test in rats.

PubMed

Wróbel, Andrzej; Serefko, Anna; Szopa, Aleksandra; Rojek, Karol; Poleszak, Ewa; Skalicka-Woźniak, Krystyna; Dudka, Jarosław

2017-08-01

Hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA) and impairment of the central corticotropin-releasing factor (CRF) system are factors in the pathogenesis of depression. Though several antagonists of the CRF 1 receptor were effective in the recognized behavioral tests for antidepressant activity, there is still little information on the potential interactions between CRF 1 receptor inhibitors and conventional antidepressant therapy. The aim of our study was to assess the influence of SN003, a CRF 1 receptor blocker, on the activity of imipramine and fluoxetine in the forced swim test (FST) in rats which presented some signs of depression. The experiments were carried out on female Wistar rats subjected to 14-day subcutaneous corticosterone (CORT) administration (20 mg/kg/day). The antidepressant-like effect was determined by the FST and the CRF levels in the hypothalamus, amygdala, and peripheral blood were measured by a high-sensitivity immunoenzymatic test. SN003 (0.5 mg/kg) potentiated the antidepressant-like effect of imipramine (15 mg/kg) and fluoxetine (7.5 mg/kg). Moreover, the co-administration of the tested agents abolished CORT-induced increase in CRF levels in the examined biological material more profoundly than monotherapy. Our present findings give further evidence that the blockage of CRF action may be useful in the treatment of mood disorders. The concurrent use of well-known antidepressants with CRF 1 receptor antagonists could be beneficial in terms of safety, since it requires lower doses of the applied agents.

Oxidative stress parameters in diabetic rats submitted to forced swimming test: the clonazepam effect.

PubMed

da Silva Haeser, Alexsandro; Sitta, Angela; Barschak, Alethéa Gatto; Deon, Marion; Barden, Amanda Thomas; Schmitt, Graziela Oliveira; Landgraff, Sharon; Gomez, Rosane; Barros, Helena M T; Vargas, Carmen Regla

2007-06-18

Diabetes-associated depression may occur due to changes in the quality of life imposed by treatment, or may be a consequence of the biochemical changes accompanying the disease. We evaluated the oxidative stress from diabetic animals submitted to an experimental model of depression and the effects of clonazepam. Male Wistar rats were induced to diabetes with streptozotocin and submitted to forced swimming test. Clonazepam was administered 24, 5 and 1 h before test. The animals were sacrificed by decapitation, and plasma and erythrocytes were separated, as well as hippocampus, cortex and striatum. Reactive species of thiobarbituric acid (TBARS) and total antioxidant reactivity (TAR) as well as antioxidant enzyme activities catalase (CAT) and superoxide dismutase (SOD) were evaluated. Results showed a significant increase of TBARS and a significant decrease of TAR in plasma from diabetic animals, which was altered by clonazepam. There were no effects of CAT and SOD activities in erythrocytes from tested animals. The results observed in hippocampus showed a significant increase of TBARS from diabetic rats, altered by clonazepam, and no one alteration was verified in TAR. The significant increase of TBARS and the significant decrease of TAR in cortex from diabetic rats were not altered by clonazepam administration. There were no alterations of TBARS and TAR in striatum from tested animals. Besides, clonazepam reverses the immobility in diabetic rats. Considering the action of clonazepam, it is suggested that it could be an alternative therapeutic for depression to diabetic patients, once it could give a protection against free radicals.

Effects of forced swimming stress on thyroid function, pituitary thyroid-stimulating hormone and hypothalamus thyrotropin releasing hormone expression in adrenalectomy Wistar rats.

PubMed

Sun, Qiuyan; Liu, Aihua; Ma, Yanan; Wang, Anyi; Guo, Xinhong; Teng, Weiping; Jiang, Yaqiu

2016-11-01

In order to study the impact that is imposed on the hypothalamic-pituitary-thyroid (HPT) axis of adrenalectomy male Wistar rats by stress caused by swimming, the blood level of triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH), the expression of TSHβ mRNA at the pituitary and thyrotropin releasing hormone (TRH) expression at the paraventricular nucleus (PVN) were measured. A total of 50 male Wistar rats of 6-8 weeks of age and with an average weight of 190-210 grams were randomly divided into the following two groups: The surgical (without adrenal glands) and non-surgical (adrenalectomy) group. These two groups were then divided into the following five groups, according to the time delay of sacrifice following forced swim (10 min, 2 h, 12 h and 24 h) and control (not subjected to swimming) groups. A bilateral adrenalectomy animal model was established. Serum TSH in the blood was measurement by chemiluminescent immunoassay, and cerebrum tissue were excised for the measurement of TRH expression using an immunohistochemistry assay. In addition, pituitaries were excised for the extraction of total RNA. Finally, reverse transcription-quantitative polymerase chain reaction was performed for quantitation of TSHβ. Following swimming, the serum T3, T4 and TSH, the TSHβ mRNA expression levels in the pituitary and the TRH expression in the PVN of the surgical group were gradually increased. In the non-surgical group, no significant differences were observed in the serum T3, T4 and TSH levels compared with the control group. The TSHβ mRNA expression at the pituitary showed a similar result. Furthermore, the TRH expression at PVN was gradually increased and stress from swimming could increase the blood T4, T3 and TSH levels, TSHβ mRNA expression at the pituitary and TRH expression at the PVN in adrenalectomy Wistar rats. Moreover, the index in the surgical group changed significantly compared with the non-surgical group. In conclusion, the results suggest that there is a positive correlation between stress from forced swimming and the variation of the HPT axis.

Numerical investigation of the hydrodynamics of carangiform swimming in the transitional and inertial flow regimes.

PubMed

Borazjani, Iman; Sotiropoulos, Fotis

2008-05-01

We employ numerical simulation to investigate the hydrodynamics of carangiform locomotion as the relative magnitude of viscous and inertial forces, i.e. the Reynolds number (Re), and the tail-beat frequency, i.e. the Strouhal number (St), are systematically varied. The model fish is a three-dimensional (3D) mackerel-like flexible body undulating with prescribed experimental kinematics of carangiform type. Simulations are carried out for three Re spanning the transitional and inertial flow regimes, Re=300 and 4000 (viscous flow), and infinity (inviscid flow). For each Re there is a critical Strouhal number, St*, at which the net mean force becomes zero, making constant-speed self-propulsion possible. St* is a decreasing function of Re and approaches the range of St at which most carangiform swimmers swim in nature (St approximately 0.25) only as Re approaches infinity. The propulsive efficiency at St* is an increasing function of Re while the power required for swimming is decreasing with Re. For all Re, however, the swimming power is shown to be significantly greater than that required to tow the rigid body at the same speed. We also show that the variation of the total drag and its viscous and form components with St depend on the Re. For Re=300, body undulations increase the drag over the rigid body level, while significant drag reduction is observed for Re=4000. This difference is shown to be due to the fact that at sufficiently high Re the drag force variation with St is dominated by its form component variation, which is reduced by undulatory swimming for St>0.2. Finally, our simulations clarify the 3D structure of various wake patterns observed in experiments--single and double row vortices--and suggest that the wake structure depends primarily on the St. Our numerical findings help elucidate the results of previous experiments with live fish, underscore the importance of scale (Re) effects on the hydrodynamic performance of carangiform swimming, and help explain why in nature this mode of swimming is typically preferred by fast swimmers.

Dietary arginine depletion reduces depressive-like responses in male, but not female, mice.

PubMed

Workman, Joanna L; Weber, Michael D; Nelson, Randy J

2011-09-30

Previous behavioral studies have manipulated nitric oxide (NO) production either by pharmacological inhibition of its synthetic enzyme, nitric oxide synthase (NOS), or by deletion of the genes that code for NOS. However manipulation of dietary intake of the NO precursor, L-arginine, has been understudied in regard to behavioral regulation. L-Arginine is a common amino acid present in many mammalian diets and is essential during development. In the brain L-arginine is converted into NO and citrulline by the enzyme, neuronal NOS (nNOS). In Experiment 1, paired mice were fed a diet comprised either of an L-arginine-depleted, L-arginine-supplemented, or standard level of L-arginine during pregnancy. Offspring were continuously fed the same diets and were tested in adulthood in elevated plus maze, forced swim, and resident-intruder aggression tests. L-Arginine depletion reduced depressive-like responses in male, but not female, mice and failed to significantly alter anxiety-like or aggressive behaviors. Arginine depletion throughout life reduced body mass overall and eliminated the sex difference in body mass. Additionally, arginine depletion significantly increased corticosterone concentrations, which negatively correlated with time spent floating. In Experiment 2, adult mice were fed arginine-defined diets two weeks prior to and during behavioral testing, and again tested in the aforementioned tests. Arginine depletion reduced depressive-like responses in the forced swim test, but did not alter behavior in the elevated plus maze or the resident intruder aggression test. Corticosterone concentrations were not altered by arginine diet manipulation in adulthood. These results indicate that arginine depletion throughout development, as well as during a discrete period during adulthood ameliorates depressive-like responses. These results may yield new insights into the etiology and sex differences of depression. Copyright © 2011 Elsevier B.V. All rights reserved.

Flowfield measurements in the wake of a robotic lamprey

PubMed Central

Hultmark, Marcus; Leftwich, Megan

2009-01-01

Experiments are reported on the hydrodynamics of a swimming robotic lamprey under conditions of steady swimming and where the thrust exceeds the drag. The motion of the robot was based on the swimming of live lampreys, which is described by an equation similar to that developed for the American eel by Tytell and Lauder (J Exp Biol 207:1825–1841, 2004). For steady swimming, the wake structure closely resembles that of the American eel, where two pairs of same sign vortices are shed each tail beat cycle, giving the wake a 2P structure. Force estimates suggest that the major part of the thrust is produced at or close to the end of the tail. PMID:19946623

Pharmacological activity of three commercial Hypericum perforatum preparations in mice.

PubMed

Jean, D; Pouligon, M; Henriot, A C

2006-08-01

St John's Wort (Hypericum perforatum) is the main herbal species used to treat depression. The products available on the pharmaceutical and dietary supplement markets are obtained by a variety of preparation processes and their pharmacological effects may differ significantly. The purpose of this study therefore was to investigate the effect of different St John's Wort commercial preparations available on the French market. Only one preparation gave significant results in the forced swimming test.

Pharmaceutical Composition for Improving Physical Working Capacity.

PubMed

Baulin, S I; Rogacheva, S M; Afanaseva, S V; Zabanova, E V; Karagaycheva, Yu V

2015-11-01

For development of a pharmaceutical composition improving physical performance, effects of various drugs and their combinations on forced swimming test performance were studied on laboratory rats. Maximum increase in animal performance was produced by a 3-component composition asparcam+mildronate+metaprote in proportion of 5.0, 10.7, and 14.3 mg/kg, respectively. No changes in blood serum biochemistry and morphological composition of the peripheral blood were detected after single intragastric administration of the composition.

No evidence for a bioenergetic advantage from forced swimming in rainbow trout under a restrictive feeding regime

PubMed Central

Skov, Peter V.; Lund, Ivar; Pargana, Alexandre M.

2015-01-01

Sustained swimming at moderate speeds is considered beneficial in terms of the productive performance of salmonids, but the causative mechanisms have yet to be unequivocally established. In the present study, the effects of moderate exercise on the bioenergetics of rainbow trout were assessed during a 15 week growth experiment, in which fish were reared at three different current speeds: 1 BL s−1, 0.5 BL s−1 and still water (≈ 0 BL s−1). Randomly selected groups of 100 fish were distributed among twelve 600 L tanks and maintained on a restricted diet regime. Specific growth rate (SGR) and feed conversion ratio (FCR) were calculated from weight and length measurements every 3 weeks. Routine metabolic rate (RMR) was measured every hour as rate of oxygen consumption in the tanks, and was positively correlated with swimming speed. Total ammonia nitrogen (TAN) excretion rates showed a tendency to decrease with increasing swimming speeds, yet neither they nor the resulting nitrogen quotients (NQ) indicated that swimming significantly reduced the fraction of dietary protein used to fuel metabolism. Energetic budgets revealed a positive correlation between energy expenditure and the current speed at which fish were reared, fish that were forced to swim and were fed restrictively consequentially had poorer growth and feed utilization. The results show that for rainbow trout, water current can negatively affect growth despite promoting minor positive changes in substrate utilization. We hypothesize that this may be the result of either a limited dietary energy supply from diet restriction being insufficient for both covering the extra costs of swimming and supporting enhanced growth. PMID:25705195

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

Zhou, Shuang; Tovkach, Oleh; Golovaty, Dmitry

Flagellated bacteria such as Escherichia coli and Bacillus subtilis exhibit effective mechanisms for swimming in fluids and exploring the surrounding environment. In isotropic fluids such as water, the bacteria change swimming direction through the run-and-tumble process. Lyotropic chromonic liquid crystals (LCLCs) have been introduced recently as an anisotropic environment in which the direction of preferred orientation, the director, guides the bacterial trajectories. In this work, we describe the behavior of bacteria B. subtilis in a homeotropic LCLC geometry, in which the director is perpendicular to the bounding plates of a shallow cell. We demonstrate that the bacteria are capable ofmore » overcoming the stabilizing elastic forces of the LCLC and swim perpendicularly to the imposed director (and parallel to the bounding plates). The effect is explained by a finite surface anchoring of the director at the bacterial body; the role of surface anchoring is analyzed by numerical simulations of a rod realigning in an otherwise uniform director field. Shear flows produced by a swimming bacterium cause director distortions around its body, as evidenced both by experiments and numerical simulations. These distortions contribute to a repulsive force that keeps the swimming bacterium at a distance of a few micrometers away from the bounding plates. The homeotropic alignment of the director imposes two different scenarios of bacterial tumbling: one with an 180° reversal of the horizontal velocity and the other with the realignment of the bacterium by two consecutive 90° turns. Finally, in the second case, the angle between the bacterial body and the imposed director changes from 90° to 0° and then back to 90°; the new direction of swimming does not correlate with the previous swimming direction.« less

Acute consumption of a caffeinated energy drink enhances aspects of performance in sprint swimmers.

PubMed

Lara, Beatriz; Ruiz-Vicente, Diana; Areces, Francisco; Abián-Vicén, Javier; Salinero, Juan José; Gonzalez-Millán, Cristina; Gallo-Salazar, César; Del Coso, Juan

2015-09-28

This study investigated the effect of a caffeinated energy drink on various aspects of performance in sprint swimmers. In a randomised and counterbalanced order, fourteen male sprint swimmers performed two acute experimental trials after the ingestion of a caffeinated energy drink (3 mg/kg) or after the ingestion of the same energy drink without caffeine (0 mg/kg; placebo). After 60 min of ingestion of the beverages, the swimmers performed a countermovement jump, a maximal handgrip test, a 50 m simulated competition and a 45 s swim at maximal intensity in a swim ergometer. A blood sample was withdrawn 1 min after the completion of the ergometer test. In comparison with the placebo drink, the intake of the caffeinated energy drink increased the height in the countermovement jump (49.4 (SD 5.3) v. 50.9 (SD 5.2) cm, respectively; P<0.05) and maximal force during the handgrip test with the right hand (481 (SD 49) v. 498 (SD 43) N; P<0.05). Furthermore, the caffeinated energy drink reduced the time needed to complete the 50 m simulated swimming competition (27.8 (SD 3.4) v. 27.5 (SD 3.2) s; P<0.05), and it increased peak power (273 (SD 55) v. 303 (SD 49) W; P <0.05) and blood lactate concentration (11.0 (SD 2.0) v. 11.7 (SD 2.1) mM; P<0.05) during the ergometer test. The caffeinated energy drink did not modify the prevalence of insomnia (7 v. 7%), muscle pain (36 v. 36%) or headache (0 v. 7%) during the hours following its ingestion (P>0.05). A caffeinated energy drink increased some aspects of swimming performance in competitive sprinters, whereas the side effects derived from the intake of this beverage were marginal at this dosage.

3D Kinematics and Hydrodynamic Analysis of Freely Swimming Cetacean

NASA Astrophysics Data System (ADS)

Ren, Yan; Sheinberg, Dustin; Liu, Geng; Dong, Haibo; Fish, Frank; Javed, Joveria

2015-11-01

It's widely thought that flexibility and the ability to control flexibility are crucial elements in determining the performance of animal swimming. However, there is a lack of quantification of both span-wise and chord-wise deformation of Cetacean's flukes and associated hydrodynamic performance during actively swimming. To fill this gap, we examined the motion and flexure of both dolphin fluke and orca fluke in steady swimming using a combined experimental and computational approach. It is found that the fluke surface morphing can effectively modulate the flow structures and influence the propulsive performance. Findings from this work are fundamental for understanding key kinematic features of effective Cetacean propulsors, and for quantifying the hydrodynamic force production that naturally occurs during different types of swimming. This work is supported by ONR MURI N00014-14-1-0533 and NSF CBET-1313217.

Free Swimming in Ground Effect

NASA Astrophysics Data System (ADS)

Cochran-Carney, Jackson; Wagenhoffer, Nathan; Zeyghami, Samane; Moored, Keith

2017-11-01

A free-swimming potential flow analysis of unsteady ground effect is conducted for two-dimensional airfoils via a method of images. The foils undergo a pure pitching motion about their leading edge, and the positions of the body in the streamwise and cross-stream directions are determined by the equations of motion of the body. It is shown that the unconstrained swimmer is attracted to a time-averaged position that is mediated by the flow interaction with the ground. The robustness of this fluid-mediated equilibrium position is probed by varying the non-dimensional mass, initial conditions and kinematic parameters of motion. Comparisons to the foil's fixed-motion counterpart are also made to pinpoint the effect that free swimming near the ground has on wake structures and the fluid-mediated forces over time. Optimal swimming regimes for near-boundary swimming are determined by examining asymmetric motions.

Ontogenetic changes in larval swimming and orientation of pre-competent sea urchin Arbacia punctulata in turbulence

PubMed Central

Wheeler, Jeanette D.; Chan, Kit Yu Karen; Anderson, Erik J.; Mullineaux, Lauren S.

2016-01-01

ABSTRACT Many marine organisms have complex life histories, having sessile adults and relying on the planktonic larvae for dispersal. Larvae swim and disperse in a complex fluid environment and the effect of ambient flow on larval behavior could in turn impact their survival and transport. However, to date, most studies on larvae–flow interactions have focused on competent larvae near settlement. We examined the importance of flow on early larval stages by studying how local flow and ontogeny influence swimming behavior in pre-competent larval sea urchins, Arbacia punctulata. We exposed larval urchins to grid-stirred turbulence and recorded their behavior at two stages (4- and 6-armed plutei) in three turbulence regimes. Using particle image velocimetry to quantify and subtract local flow, we tested the hypothesis that larvae respond to turbulence by increasing swimming speed, and that the increase varies with ontogeny. Swimming speed increased with turbulence for both 4- and 6-armed larvae, but their responses differed in terms of vertical swimming velocity. 4-Armed larvae swam most strongly upward in the unforced flow regime, while 6-armed larvae swam most strongly upward in weakly forced flow. Increased turbulence intensity also decreased the relative time that larvae spent in their typical upright orientation. 6-Armed larvae were tilted more frequently in turbulence compared with 4-armed larvae. This observation suggests that as larvae increase in size and add pairs of arms, they are more likely to be passively re-oriented by moving water, rather than being stabilized (by mechanisms associated with increased mass), potentially leading to differential transport. The positive relationship between swimming speed and larval orientation angle suggests that there was also an active response to tilting in turbulence. Our results highlight the importance of turbulence to planktonic larvae, not just during settlement but also in earlier stages through morphology–flow interactions. PMID:27208032

The effects of Taraxacum officinale extracts (TOE) supplementation on physical fatigue in mice.

PubMed

Jinchun, Zhang; Jie, Chen

2011-01-01

The study is to investigate the effect of Taraxacum officinale extracts (TOE) supplementation on physical fatigue based on the forced swimming capacity in mice. Forty Kunming male mice were randomly divided into 4 groups, i.e., normal control (NC) and three doses of TOE treated group (High-dose, Middle-dose and Low-dose). Three TOE treated groups were treated by oral TOE with 10, 30 and 100mg/kg b.w respectively for a period of 42 days. The normal control group was given a corresponding volume of sterile distilled water. After 6 weeks, the forced swimming capacity and blood biochemical parameters in mice were measured, and the result showed that TOE had an anti- physical fatigue effect. It enhanced the maximum swimming capacity of mice, effectively delayed the lowering of glucose in the blood, and prevented the increase in lactate and triglyceride concentrations.

Effect of wearing clothes on oxygen uptake and ratings of perceived exertion while swimming.

PubMed

Choi, S W; Kurokawa, T; Ebisu, Y; Kikkawa, K; Shiokawa, M; Yamasaki, M

2000-07-01

For a comparative study between swimming in swimwear (control-sw) and swimming in clothes (clothes-sw), oxygen uptake (VO2) and ratings of perceived exertion (RPE) were measured. The subjects were six male members of a university swimming team. Three swimming strokes--the breaststroke, the front crawl stroke and the elementary backstroke--were applied. With regards to clothes-sw, swimmers wore T-shirts, sportswear (shirt and pants) over swimwear and running shoes. In both cases of control-sw and clothes-sw, the VO2 was increased exponentially with increased swimming speed. The VO2 of the subjects during the clothed tests did not exceed 1.4 times of that in the case of control-sw at swimming speeds below 0.3 m/s. As swimming speeds increased, VO2 difference in both cases increased. Consequently, VO2 in the clothed tests was equal to 1.5-1.6 times and 1.5-1.8 times of that in the swimwear tests at speeds of 0.5 and 0.7 m/s, respectively. At speeds below 0.6 m/s in clothes-sw, the breaststroke showed lower VO2 than the front crawl stroke, and the elementary backstroke showed higher VO2 than the other two swimming strokes. RPE increased linearly with %peak VO2. In addition, any RPE differences among the three swimming strokes were not shown in the control-sw tests. At an exercise intensity above 60 %peak VO2, clothed swimmers showed slightly higher RPE in the front crawl stroke compared to that in the two other swimming strokes.

Evidence for the involvement of NMDA receptors in the antidepressant-like effect of nicotine in mouse forced swimming and tail suspension tests.

PubMed

Haj-Mirzaian, Arya; Kordjazy, Nastaran; Haj-Mirzaian, Arvin; Ostadhadi, Sattar; Ghasemi, Mehdi; Amiri, Shayan; Faizi, Mehrdad; Dehpour, AhmadReza

2015-10-01

The antidepressant action of acute nicotine administration in clinical and animal studies is well recognized. But the underlying mechanism for this effect has not been carefully discovered. We attempted to evaluate the possible role of N-Methyl-D-aspartate (NMDA) receptors in the antidepressant-like effect of nicotine. After the assessment of locomotor activity in the open-field test, forced swimming test (FST) and tail suspension test (TST) were used to evaluate the antidepressant-like effect of nicotine in mice. We performed intraperitoneal administration of nicotine at different doses and periods before the tests. To assess the possible involvement of NMDA receptors, non-effective doses of NMDA antagonists and an NMDA agonist were obtained and were administered simultaneously with the non-effective and effective doses of nicotine, respectively. Nicotine (0.2 mg/kg, 30 min before FST/TST) significantly reduced the immobility time of mice similar to fluoxetine (20 mg/kg). Nicotine did not affect the locomotor behavior of mice in open-field test. Co-administration of non-effective doses of NMDA receptor antagonists, ketamine (1 or 0.3 mg/kg), MK-801 (0.05 or 0.005 mg/kg), and magnesium sulfate (10 or 5 mg/kg) with nicotine (0.1 or 0.03 mg/kg) had remarkable synergistic antidepressant effect in both FST and TST. Also, non-effective NMDA (75 or 30 mg/kg) reversed the anti-immobility effect of nicotine (0.2 mg/kg) on mouse FST and TST. Our study has for the first time confirmed that the antidepressant-like effect of nicotine on mice is NMDA-mediated, and nicotine presumably exerts this effect by antagonizing the glutamatergic NMDA receptors.

Leishmania amazonensis chemotaxis under glucose gradient studied by the strength and directionality of forces measured with optical tweezers

NASA Astrophysics Data System (ADS)

de Ysasa Pozzo, Liliana; Fontes, Adriana; de Thomaz, André A.; Barbosa, Luiz Carlos; Ayres, Diana Copi; Giorgio, Selma; Cesar, Carlos Lenz

2007-02-01

Chemotaxis is the mechanism microorganisms use to sense the environment surrounding them and to direct their movement towards attractive, or away from the repellent, chemicals. The biochemical sensing is almost the only way for communication between unicellular organisms. Prokaryote and Eukaryote chemotaxis has been mechanically studied mainly by observing the directionality and timing of the microorganisms movements subjected to a chemical gradient, but not through the directionality and strength of the forces it generates. To observe the vector force of microorganisms under a chemical gradient we developed a system composed of two large chambers connected by a tiny duct capable to keep the chemical gradient constant for more than ten hours. We also used the displacements of a microsphere trapped in an Optical Tweezers as the force transducer to measure the direction and the strength of the propulsion forces of flagellum of the microorganism under several gradient conditions. A 9μm diameter microsphere particle was trapped with a Nd:YAG laser and its movement was measured through the light scattered focused on a quadrant detector. We observed the behavior of the protozoa Leishmania amazonensis (eukaryote) under several glucose gradients. This protozoa senses the gradient around it by swimming in circles for three to five times following by tumbling, and not by the typical straight swimming/tumbling of bacteria. Our results also suggest that force direction and strength are also used to control its movement, not only the timing of swimming/tumbling, because we observed a higher force strength clearly directed towards the glucose gradient.

Orally administered whole egg demonstrates antidepressant-like effects in the forced swimming test on rats.

PubMed

Nagasawa, Mao; Otsuka, Tsuyoshi; Ogino, Yumi; Yoshida, Junki; Tomonaga, Shozo; Yasuo, Shinobu; Furuse, Mitsuhiro

2014-08-01

Several studies have reported that vegetarian diets are associated with a higher prevalence of major depression. Therefore, we hypothesised that the consumption of animal products, especially eggs, may have positive effects on mental health, especially on major depression, because a previous study reported that egg consumption produces numerous beneficial effects in humans. The purpose of the present study was to evaluate the effects of chronic whole-egg treatment on depression-like behaviours in Wistar rats, a control strain, and Wistar Kyoto rats, an animal model of depression. In both the rats, either whole-egg solution (5 ml/kg) or distilled water (5 ml/kg) was orally administrated for 35 days. During these periods, the open-field test (OFT) was conducted on the 21st day, and a forced swimming test (FST) was enforced on the 27th and 28th days. On the 36th day, the plasma and brain were collected. Chronic whole-egg treatment did not affect line crossing in the OFT, whereas it reduced the total duration of immobility in the FST on both strains. Furthermore, interestingly, the results indicated the possibility that whole-egg treatment elevated the incorporation of tryptophan into the brain, and the tryptophan concentration in the prefrontal cortex was actually increased by the treatment. This study demonstrated that whole-egg treatment exerts an antidepressant-like effect in the FST. It is suggested that whole egg may be an excellent food for preventing and alleviating the conditions of major depression.

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.

Effect of addition of yohimbine (alpha-2-receptor antagonist) to the antidepressant activity of fluoxetine or venlafaxine in the mouse forced swim test.

PubMed

Dhir, Ashish; Kulkarni, S K

2007-01-01

Studies have suggested that alpha(2)-adrenoceptors strongly affect monoaminergic neurotransmission by enhancing not only noradrenergic but also serotonergic firing rates. With this background in mind, the present study was undertaken to monitor the effect of addition of yohimbine (alpha(2)-adrenoceptor antagonist) to the effect of fluoxetine (selective serotonin reuptake inhibitor) or venlafaxine (dual reuptake inhibitors of both serotonin and norepinephrine) in Porsolt's forced swim test (FST) using male Laca strain mice. The immobility period was recorded in mouse FST during a 6-min period. Different doses of fluoxetine or venlafaxine were administered 30 min before exposing the animals to the test procedure. In the combination study, yohimbine (2 mg/kg i.p.) was administered 15 min before the administration of different doses of fluoxetine or venlafaxine. Fluoxetine (5, 10, 20 and 40 mg/kg) [F = 28.352] or venlafaxine (2, 4, 8 and 16 mg/kg) [F = 17.842] dose-dependently inhibited the immobility period in mice. Addition of yohimbine (2 mg/kg i.p.) potentiated the antidepressant action of fluoxetine or venlafaxine in mouse FST as the animals showed a decrease in the immobility period compared to the fluoxetine or venlafaxine per se group, respectively. The present study not only demonstrated the association of alpha(2)-receptors in the antidepressant effect of fluoxetine or venlafaxine, but also supports its adjuvant therapy with other antidepressant drugs. (c) 2007 S. Karger AG, Basel.

Papaver Rhoeas L. Hydroalcoholic Extract Exacerbates Forced Swimming Test-Induced Depression in Mice.

PubMed

Osanloo, Naser; Najafi-Abedi, Akram; Jafari, Fatemeh; Javid, Farshid; Pirpiran, Mohsen; Memar Jafari, Mohammad-Reza; Mousavi Khosravi, Seyed Ali; Rahimzadeh Behzadi, Mohammad; Ranjbaran, Mina; Sahraei, Hedayat

2016-07-01

Depression is one of the most frequent psychiatric disorders in the world with occurs with higher incidence in women. In the present study, the effect of water-alcoholic extract of Papaver rhoeas L. on forced swimming test (FST) in Swiss-Webster mice were examined. We used Swiss-Webster mice (20-25 g) to execute FST on them. The plant extract (1, 10, 30, and 100 mg/kg) was injected to the animals 30 minutes before each session. Fluoxetine (20 mg/kg) was used as standard antidepressant drug. In another group of animals, 30 minutes after extract administration, blood samples were taken from retro-orbital sinus for corticosterone assay. Yet in third group, the drugs were injected to the animals and 30 minutes later, their activities were tested in an open field apparatus. Our experiments showed that the extract efficiently reduced FST time both in male and female mice dose-dependently. This effect was comparable with fluoxetine. In addition, corticosterone assay indicated that plasma corticosterone in animals which received extract was higher than those amounts in fluoxetine and saline controls. Moreover, the animals did not show any motor activity deficit in all doses of the extract and fluoxetine compared to saline control. The extract of Papaver rhoeas can reduce immobility time which is comparable to the effect of fluoxetine. Also the effect of the extract is contrary to its effects on plasma corticosterone level and or animals' activity.

Aging exacerbates depressive-like behavior in mice in response to activation of the peripheral innate immune system.

PubMed

Godbout, Jonathan P; Moreau, Maïté; Lestage, Jacques; Chen, Jing; Sparkman, Nathan L; O'Connor, Jason; Castanon, Nathalie; Kelley, Keith W; Dantzer, Robert; Johnson, Rodney W

2008-09-01

Exposure to peripheral infections may be permissive to cognitive and behavioral complications in the elderly. We have reported that peripheral stimulation of the innate immune system with lipopolysaccharide (LPS) causes an exaggerated neuroinflammatory response and prolonged sickness behavior in aged BALB/c mice. Because LPS also causes depressive behavior, the purpose of this study was to determine whether aging is associated with an exacerbated depressive-like response. We confirmed that LPS (0.33 mg/kg intraperitoneal) induced a protracted sickness response in aged mice with reductions in locomotor and feeding activities 24 and 48 h postinjection, when young adults had fully recovered. When submitted to the forced swim test 24 h post-LPS, both young adult and aged mice exhibited an increased duration of immobility. However, when submitted to either the forced swim test or the tail suspension test 72 h post-LPS, an increased duration of immobility was evident only in aged mice. This prolonged depressive-like behavior in aged LPS-treated mice was associated with a more pronounced induction of peripheral and brain indoleamine 2,3-dioxygenase and a markedly higher turnover rate of brain serotonin (as measured by the ratio of 5-hydroxy-indoleacetic acid over 5-hydroxy-tryptamine) compared to young adult mice at 24 post-LPS injection. These results provide the first evidence that age-associated reactivity of the brain cytokine system could play a pathophysiological role in the increased prevalence of depression observed in the elderly.

1-Oleoyl Lysophosphatidic Acid: A New Mediator of Emotional Behavior in Rats

PubMed Central

Castilla-Ortega, Estela; Escuredo, Leticia; Bilbao, Ainhoa; Pedraza, Carmen; Orio, Laura; Estivill-Torrús, Guillermo; Santín, Luis J.; de Fonseca, Fernando Rodríguez; Pavón, Francisco Javier

2014-01-01

The role of lysophosphatidic acid (LPA) in the control of emotional behavior remains to be determined. We analyzed the effects of the central administration of 1-oleoyl-LPA (LPA 18∶1) in rats tested for food consumption and anxiety-like and depression-like behaviors. For this purpose, the elevated plus-maze, open field, Y maze, forced swimming and food intake tests were performed. In addition, c-Fos expression in the dorsal periaqueductal gray matter (DPAG) was also determined. The results revealed that the administration of LPA 18∶1 reduced the time in the open arms of the elevated plus-maze and induced hypolocomotion in the open field, suggesting an anxiogenic-like phenotype. Interestingly, these effects were present following LPA 18∶1 infusion under conditions of novelty but not under habituation conditions. In the forced swimming test, the administration of LPA 18∶1 dose-dependently increased depression-like behavior, as evaluated according to immobility time. LPA treatment induced no effects on feeding. However, the immunohistochemical analysis revealed that LPA 18∶1 increased c-Fos expression in the DPAG. The abundant expression of the LPA1 receptor, one of the main targets for LPA 18∶1, was detected in this brain area, which participates in the control of emotional behavior, using immunocytochemistry. These findings indicate that LPA is a relevant transmitter potentially involved in normal and pathological emotional responses, including anxiety and depression. PMID:24409327

Leptin receptor deficiency confers resistance to behavioral effects of fluoxetine and desipramine via separable substrates.

PubMed

Guo, M; Lu, X-Y

2014-12-02

Depression is a complex, heterogeneous mental disorder. Currently available antidepressants are only effective in about one-third to one-half of all patients. The mechanisms underlying antidepressant response and treatment resistance are poorly understood. Recent clinical evidence implicates the involvement of leptin in treatment response to antidepressants. In this study, we determined the functional role of the leptin receptor (LepRb) in behavioral responses to the selective serotonergic antidepressant fluoxetine and the noradrenergic antidepressant desipramine. While acute and chronic treatment with fluoxetine or desipramine in wild-type mice elicited antidepressant-like effects in the forced swim test, mice null for LepRb (db/db) displayed resistance to treatment with either fluoxetine or desipramine. Fluoxetine stimulated phosphorylation of Akt(Thr308) and GSK-3β(Ser9) in the hippocampus and prefrontal cortex (PFC) of wild-type mice but not in db/db mice. Desipramine failed to induce measurable changes in Akt, GSK-3β or ERK1/2 phosphorylation in the hippocampus and PFC, as well as hypothalamus of either genotype of mice. Deletion of LepRb specifically from hippocampal and cortical neurons resulted in fluoxetine insensitivity in the forced swim test and tail suspension test while leaving the response to desipramine intact. These results suggest that functional LepRb is critically involved in regulating the antidepressant-like behavioral effects of both fluoxetine and desipramine. The antidepressant effects of fluoxetine but not desipramine are dependent on the presence of functional LepRb in the hippocampus and cortex.

Vitamin C impacts anxiety-like behavior and stress-induced anorexia relative to social environment in SMP30/GNL knockout mice.

PubMed

Koizumi, Miwako; Kondo, Yoshitaka; Isaka, Ayumi; Ishigami, Akihito; Suzuki, Emiko

2016-12-01

The role of endogenous vitamin C (VC) in emotion and psychiatric measures has long been uncertain. We aimed to investigate how an individual's VC status impacts his or her mental health. Our hypothesis is that body VC levels modulate anxiety, anorexia, and depressive phenotypes under the influence of psychosocial rearing environments and sex. The VC status of senescence marker protein-30/gluconolactonase knockout mice, which lack the ability to synthesize VC, were continuously shifted from adequate (VC+) to depleted (VC-) by providing a water with or without VC. Despite weight loss in both sexes, suppressed feeding was specifically seen in males only during the VC- phase. Anxiety responses in the novelty-suppressed feeding paradigm were worse during the VC-, especially in females. Sensitivity to the forced swim test as determined by the initial latency was significantly shorter in the socially stable animals compared with socially unstable animals during the VC+ condition. The stress coping underlying depressive phenotypes was assessed by immobility duration in a series of forced swim tests. No significant differences were apparent between contrasting VC status. Homeostatic symptoms following stressful behavioral tests consisted of a great loss of appetite during the VC-. It should be noted that anorexia is extremely serious for the females. We conclude that endogenous VC status is critical for determining vulnerability to anxiety and anorexia in a sex-specific manner. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of Withania somnifera on forced swimming test induced immobility in mice and its interaction with various drugs.

PubMed

Shah, P C; Trivedi, N A; Bhatt, J D; Hemavathi, K G

2006-01-01

The objective of the present study was to evaluate the antidepressant action of Withania somnifera (WS) as well as its interaction with the conventional antidepressant drugs and to delineate the possible mechanism of its antidepressant action using forced swimming model in mice. Effect of different doses of WS, fluoxetine and imipramine were studied on forced swimming test induced mean immobility time (MIT). Moreover effect of WS 100 mg/kg, i.p. was observed at different time intervals. Effect produced by combination of sub therapeutic doses of WS with imipramine (2.5 mg/kg, i.p.) as well as fluoxetine (2.5 mg/kg, i.p.) were also observed. Effect of WS (100 mg/kg, i.p.) as well as combination of WS (37.5 mg/kg, i.p.) with either imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.) were observed in mice pretreated with reserpine (2 mg/kg, i.p.) and clonidine (0.15 mg/kg, i.p.). Effects of prazosin (3 mg/kg, i.p.) or haloperidol (0.1 mg/kg, i.p.) pre-treatment were also observed on WS induced decrease in MIT. WS produced dose dependent decrease in MIT. Maximum effect in MIT was observed after 30 min of treatment with WS 100 mg/kg, i.p. Combination of WS (37.5 mg/kg, i.p.) with imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.) also produced significant decrease in the MIT. Clonidine and reserpine induced increase in MIT, was significantly reversed by treatment with WS (100 mg/kg, i.p.) as well as combination of WS (37.5 mg/kg, i.p.) with either imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.). Pre-treatment with prazosin but not haloperidol, significantly antagonized the WS (100 mg/kg, i.p.) induced decrease in MIT. It is concluded that, WS produced significant decrease in MIT in mice which could be mediated partly through a adrenoceptor as well as alteration in the level of central biogenic amines.

Muscle-protective effects of Schisandrae Fructus extracts in old mice after chronic forced exercise.

PubMed

Kim, Ki-Young; Ku, Sae-Kwang; Lee, Ki-Won; Song, Chang-Hyun; An, Won G

2018-02-15

Schisandrae Fructus (SF), the dried fruit of Schisandra chinensis (Turcz.) Baill., is a well-known traditional herb used in Asia for enhancing physical work capacity as well as providing anti-stress and anti-inflammatory effects. Extracts of SF (SFe) have also been reported to increase skeletal muscle mass and inhibit muscle atrophy. We examined whether SFe had muscle-protective effects in old mice after chronic forced exercises, and, if so, relevant mechanisms. Ten-month-old aged male mice were divided into six groups. One group received no forced swimming after oral administration of distilled water (Intact); the other groups received forced swimming after administration of distilled water (SW), oxymetholone (OXY), or SFe at 500, 250 and 125mg/kg (SFe500, SFe250, and SFe125, respectively). Forced swimming was conducted for 2min at 30min after oral administration; the treatment was repeated for 28 days. Muscle thickness, weight, lean proportion, and strength were examined. The sampled muscles were subjected to histopathological and biochemical analyses. Plasma was examined by biochemical analyses. The thicknesses of the calf muscle and the sampled gastrocnemius and soleus, protein proportion and muscle strength increased significantly in the SW group versus Intact, and they were further increased in the SFe and OXY groups versus SW. The forced swimming in the SW group upregulated mRNA expression related to protein synthesis (Akt1, PI3K) and muscle growth (A1R, TRPV4), while it downregulated mRNAs related to protein degradation (atrogin-1, MuRF1) and muscle growth inhibitor (myostatin, SIRT1). The detected upregulation and downregulation were enhanced in the SFe groups. In addition, the SFe administration inhibited lipid peroxidation and reactive oxygen species, and accelerated activities of endogenous anti-oxidants and anti-oxidant enzymes. Plasma biochemistry showed decreases in creatine, creatine kinase and LDH in the SFe groups versus SW, suggesting muscle-protective effects of SFe. In the SFe groups versus SW, histopathological analyses revealed an increase in myofibre diameter, and immunohistochemistry showed increases in myofibres immunoreactive for ATPase and decreases in myofibres for apoptosis markers (caspase-3, PARP) and oxidative stress markers (NT, 4HNE, iNOS). Oral administration of SFe, especially SFe500, enhanced exercise-induced adaptive muscle strengthening in aged mice after forced swimming through anti-apoptotic and anti-oxidant effects, mediated via modulation of gene expression related to muscle synthesis or degradation. These results suggest that SFe may be helpful in improvement various muscle disorders as an adjuvant therapy to exercise-based remedies. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of jellyfish turning using 3D-PTV

NASA Astrophysics Data System (ADS)

Xu, Nicole; Dabiri, John

2017-11-01

Aurelia aurita are oblate, radially symmetric jellyfish that consist of a gelatinous bell and subumbrellar muscle ring, which contracts to provide motive force. Swimming is typically modeled as a purely vertical motion; however, asymmetric activations of swim pacemakers (sensory organs that innervate the muscle at eight locations around the bell margin) result in turning and more complicated swim behaviors. More recent studies have examined flow fields around turning jellyfish, but the input/output relationship between locomotive controls and swim trajectories is unclear. To address this, bell kinematics for both straight swimming and turning are obtained using 3D particle tracking velocimetry (3D-PTV) by injecting biocompatible elastomer tags into the bell, illuminating the tank with ultraviolet light, and tracking the resulting fluorescent particles in a multi-camera setup. By understanding these kinematics in both natural and externally controlled free-swimming animals, we can connect neuromuscular control mechanisms to existing flow measurements of jellyfish turning for applications in designing more energy efficient biohybrid robots and underwater vehicles. NSF GRFP.

The Impact of Immediate Verbal Feedback on the Improvement of Swimming Technique

PubMed Central

Zatoń, Krystyna; Szczepan, Stefan

2014-01-01

The present research attempts to ascertain the impact of immediate verbal feedback (IVF) on modifications of stroke length (SL). In all swimming styles, stroke length is considered an essential kinematic parameter of the swimming cycle. It is important for swimming mechanics and energetics. If SL shortens while the stroke rate (SR) remains unchanged or decreases, the temporal-spatial structure of swimming is considered erroneous. It results in a lower swimming velocity. Our research included 64 subjects, who were divided into two groups: the experimental – E (n=32) and the control – C (n=32) groups. A pretest and a post-test were conducted. The subjects swam the front crawl over the test distance of 25m at Vmax. Only the E group subjects were provided with IVF aiming to increase their SL. All tests were filmed by two cameras (50 samples•s-1). The kinematic parameters of the swimming cycle were analyzed using the SIMI Reality Motion Systems 2D software (SIMI Reality Motion Systems 2D GmbH, Germany). The movement analysis allowed to determine the average horizontal swimming velocity over 15 meters. The repeated measures analysis of variance ANOVA with a post-hoc Tukey range test demonstrated statistically significant (p<0.05) differences between the two groups in terms of SL and swimming velocity. IVF brought about a 6.93% (Simi method) and a 5.09% (Hay method) increase in SL, as well as a 2.92% increase in swimming velocity. PMID:25114741

Behavioral effects of ketamine and toxic interactions with psychostimulants

PubMed Central

Hayase, Tamaki; Yamamoto, Yoshiko; Yamamoto, Keiichi

2006-01-01

Background The anesthetic drug ketamine (KT) has been reported to be an abused drug and fatal cases have been observed in polydrug users. In the present study, considering the possibility of KT-enhanced toxic effects of other drugs, and KT-induced promotion of an overdose without making the subject aware of the danger due to the attenuation of several painful subjective symptoms, the intraperitoneal (i.p.) KT-induced alterations in behaviors and toxic interactions with popular co-abused drugs, the psychostimulants cocaine (COC) and methamphetamine (MA), were examined in ICR mice. Results A single dose of KT caused hyperlocomotion in a low (30 mg/kg, i.p.) dose group, and hypolocomotion followed by hyperlocomotion in a high (100 mg/kg, i.p.) dose group. However, no behavioral alterations derived from enhanced stress-related depression or anxiety were observed in the forced swimming or the elevated plus-maze test. A single non-fatal dose of COC (30 mg/kg, i.p.) or MA (4 mg/kg, i.p.) caused hyperlocomotion, stress-related depression in swimming behaviors in the forced swimming test, and anxiety-related behavioral changes (preference for closed arms) in the elevated plus-maze test. For the COC (30 mg/kg) or MA (4 mg/kg) groups of mice simultaneously co-treated with KT, the psychostimulant-induced hyperlocomotion was suppressed by the high dose KT, and the psychostimulant-induced behavioral alterations in the above tests were reversed by both low and high doses of KT. For the toxic dose COC (70 mg/kg, i.p.)- or MA (15 mg/kg, i.p.)-only group, mortality and severe seizures were observed in some animals. In the toxic dose psychostimulant-KT groups, KT attenuated the severity of seizures dose-dependently. Nevertheless, the mortality rate was significantly increased by co-treatment with the high dose KT. Conclusion Our results demonstrated that, in spite of the absence of stress-related depressive and anxiety-related behavioral alterations following a single dose of KT treatment, and in spite of the KT-induced anticonvulsant effects and attenuation of stress- and anxiety-related behaviors caused by COC or MA, the lethal effects of these psychostimulants were increased by KT. PMID:16542420

The antidepressant effect of an antiulcer pentadecapeptide BPC 157 in Porsolt's test and chronic unpredictable stress in rats. A comparison with antidepressants.

PubMed

Sikiric, P; Separovic, J; Buljat, G; Anic, T; Stancic-Rokotov, D; Mikus, D; Marovic, A; Prkacin, I; Duplancic, B; Zoricic, I; Aralica, G; Lovric-Bencic, M; Ziger, T; Perovic, D; Rotkvic, I; Mise, S; Hanzevacki, M; Hahn, V; Seiwerth, S; Turkovic, B; Grabarevic, Z; Petek, M; Rucman, R

2000-01-01

Various antidepressants have antiulcer activity. Likewise, the models currently used in ulcers and depression disorders research have a considerable degree of similarity. Therefore, the possibility that depression disorders could be effectively influenced by a primary antiulcer agent with a cyto/organoprotective activity, such as the novel stomach pentadecapeptide BPC 157, was investigated in two rat depression assays. First, a forced swimming test (a Porsolt's procedure) was used. As a more severe procedure, chronic unpredictable stress (after 5 d of unpredictable stress protocol, once daily drug application during stress procedure, open field-immobility test assessment at fourth or sixth day of medication) was used. In a forced swimming test, a reduction of the immobility time in BPC 157 (10 microg, 10 ng x kg(-1) i.p.) treated rats corresponds to the activity of the 15 mg or 40 mg (i.p.) of conventional antidepressants, imipramine or nialamide, respectively, given according to the original Porsolt's protocol. In chronic unpredictable stress procedure, particular aggravation of experimental conditions markedly affected the conventional antidepressant activity, whereas BPC 157 effectiveness was continuously present. The effect of daily imipramine (30 mg) medication could be seen only after a more prolonged period, but not after a shorter period (i.e., 4-d protocol). In these conditions, no delay in the effectiveness was noted in BPC 157 medication and a reduction of the immobility of chronically stressed rats was noted after both 4 and 6 d of BPC 157 (10 microg, 10 ng) medication.

Antidepressant-like effects of Perilla frutescens seed oil during a forced swimming test.

PubMed

Lee, Hsiu-Chuan; Ko, Hsiang-Kai; Huang, Brian E T-G; Chu, Yan-Hwa; Huang, Shih-Yi

2014-05-01

Unipolar depressive disorder may become one of the major leading causes of disease burden by 2030 according to the World Health Organization (WHO). Thus, the discovery of antidepressive foods is attractive and could have considerable impacts worldwide. We investigated the antidepressant-like effects of Perilla frutescens seed oil on adult male rats subjected to a forced swimming test (FST). Forty Sprague-Dawley rats were housed and fed various diets, including soybean oil-rich, eicosapentaenoic acid (EPA)-rich, and P. frutescens seed oil-rich diets for 6 weeks. After the dietary intervention, animals were tested using an FST and were sacrificed after the test. We analyzed the fatty acid profiles of red blood cells (RBCs) and the brain prefrontal cortex (PFC). Levels of brain-derived neurotrophic factor (BDNF), serotonin, and dopamine in the PFC were also determined. After the FST, the imipramine, EPA-rich, and P. frutescens seed oil-rich groups showed significant shorter immobility time and longer struggling time than the control group (p < 0.05). Levels of BDNF in the P. frutescens seed oil-rich group and levels of serotonin in the EPA-rich group were significantly (p < 0.05) higher than those of the control group. Moreover, the BDNF concentration in the PFC was significantly positively correlated with the struggling time. However, there were no significant differences in dopamine levels between the intervention groups and the control group. In conclusion, a P. frutescens seed oil-rich diet exhibited antidepressant-like properties through modulation of fatty acid profiles and BDNF expression in the brain during an FST.

Reduction in the latency of action of antidepressants by 17 beta-estradiol in the forced swimming test.

PubMed

Estrada-Camarena, E; Rivera, N M Vega; Berlanga, C; Fernández-Guasti, A

2008-12-01

Antidepressants (ADs) are slow to produce their therapeutic effect. This long latency promotes the development of new strategies to short their onset of action. Previous reports indicated that 17beta-estradiol (E(2)) promotes the antidepressant-like activity of fluoxetine (FLX) and desipramine (DMI) in the forced swimming test (FST). The aim of the present work was to analyze if E(2) reduces the antidepressant-like onset of action of venlafaxine (VLX), FLX, and DMI. Independent groups of ovariectomized female Wistar rats were tested in the FST and in the open field after chronic (1 to 14 days) treatment with VLX (20 mg/kg/day), FLX (1.25 mg/kg/day), or DMI (1.25 mg/kg/day) alone or in combination with a single injection of E(2) (2.5 microg/rat sc, 8 h before FST). VLX, FLX, or DMI by themselves at these doses did not induce changes in the FST at short intervals after their injection (from 1 to 7 days). The addition of E(2) promoted the antidepressant-like effect of VLX and DMI as early as day 1. Such action was also evident after 3, for FLX, and 14 days for both FLX and DMI, but not for VLX. The behavioral actions of these ADs combined with E(2) were not accompanied by increases in general activity in the open-field test. E(2) clearly reduced the latency to the onset of action for these ADs in the FST. These results represent an interesting therapeutic strategy for the treatment of depression in perimenopausal women.

Chronic unpredictable mild stress-induced depressive-like behavior and dysregulation of brain levels of biogenic amines in Drosophila melanogaster.

PubMed

Araujo, Stífani Machado; Poetini, Marcia Rósula; Bortolotto, Vandreza Cardoso; de Freitas Couto, Shanda; Pinheiro, Franciane Cabral; Meichtry, Luana Barreto; de Almeida, Francielli Polet; Santos Musachio, Elize Aparecida; de Paula, Mariane Trindade; Prigol, Marina

2018-05-24

The etiopathogenesis of depression may involve repeated exposure to several unpredictable stressors. This study was conducted to investigate changes induced by chronic unpredictable mild stress (CUMS) and to assess behavioral and neurochemical changes that predict depressive-like behavior in Drosophila melanogaster. Male Drosophila melanogaster flies were exposed to CUMS with several stressors (cold, heat, starvation, and sleep deprivation) in an unpredictable and chronic manner for ten days. At the end of treatment, in vivo behavioral tests (open field, aggression, forced swimming, mating, light/dark box, male fertility evaluation, sucrose preference, weight evaluation) and ex vivo analyses (dopamine and serotonin levels) were performed. Using this CUMS model, we obtained results that contribute to the construction of a depressive model in Drosophila, where we reproduce some behavioral phenotypes corresponding to depressive symptoms, such as immobility in the forced swimming test, less exploration in the light/dark test, changes in mating behavior, changes in the aggressiveness test, reduced sucrose preference, and weight-loss, in addition to a significant reduction in the levels of serotonin and dopamine when compared to the control group. Fluoxetine was used in our study as a positive control to demonstrate that CUMS-induced depressive-like behaviors in flies can be reversed by antidepressants. In conclusion, male Drosophila melanogaster exposed to CUMS display a depressive-like phenotype, and, while this poses some limitations as an animal model for depression, it meets some of the criteria required to be a valid model, such as good face and construct validity. Copyright © 2018. Published by Elsevier B.V.

The effect of GABAmimetics on the duration of immobility in the forced swim test in albino mice.

PubMed

El Zahaf, Najwa Ahmed; Salem Elhwuegi, Abdalla

2014-01-01

Studies regarding the role of gamma aminobutyric acid (GABA) in depression are conflicting. Therefore, it was decided to examine the effect of different drugs that enhance the GABA system on the time of immobility induced by the forced swim test (FST). Adult albino mice were divided into several groups of six animals. Each group received an intraperitoneal injection of either imipramine (10, 20, or 30 mg/kg), diazepam (0.5, 1, or 2 mg/kg), vigabatrin (100, 200, or 300 mg/kg), zolpidem (2.5, 5, or 10 mg/kg), or alprazolam (1, 2.5, or 5 mg/kg). Control groups received the appropriate vehicle. One hour after injection, the duration of immobility was measured for 5 min in the FST. The percentage change in the duration of immobility from the control was calculated for each group. The statistical test of the difference between the treated and the control groups was calculated using unpaired Student's t-test. Imipramine produced a significant dose-dependent decrease in the duration of immobility (78, 74, and 56%, respectively). Different doses of diazepam, vigabatrin, and zolpidem produced a significant increase in the duration of immobility (119, 126, and 128%), (116, 124, and 128%), and (108, 109, and 119%), respectively. The two low doses of alprazolam produced a significant increase (115 and 120%), while the high dose produced a significant decrease in the duration of immobility (74%). Increasing central GABAergic activity by different mechanisms has resulted in a depressant-like activity measured as an increase in the duration of immobility in the FST model of depression.

Swimming endurance of bull trout, lake trout, arctic char, and rainbow trout following challenge with Renibacterium salmoninarum

USGS Publications Warehouse

Jones, D.T.; Moffitt, C.M.

2004-01-01

We tested the swimming endurance of juvenile bull trout Salvelinus confluentus, lake trout S. namaycush, Arctic char S. alpinus, and rainbow trout Oncorhynchus mykiss at 9??C and 15??C to determine whether sublethal infection from a moderate challenge of Renibacterium salmoninarum administered months before testing affected the length of time fish could maintain a swimming speed of 5-6 body lengths per second in an experimental flume. Rainbow trout and Arctic char swam longer in trials than did bull trout or lake trout, regardless of challenge treatment. When we tested fish 14-23 weeks postchallenge, we found no measurable effect of R. salmoninarum on the swimming endurance of the study species except for bull trout, which showed a mixed response. We conducted additional trials with bull trout 5-8 weeks postchallenge to determine whether increasing the challenge dose would affect swimming endurance and hematocrit. In those tests, bull trout with clinical signs of disease and those exposed to the highest challenge doses had significantly reduced swimming endurance compared with unchallenged control fish. Fish hematocrit levels measured at the end of all swimming endurance tests varied among species and between test temperatures, and patterns were not always consistent between challenged and control fish.

Duloxetine and 8-OH-DPAT, but not fluoxetine, reduce depression-like behaviour in an animal model of chronic neuropathic pain.

PubMed

Hu, Bing; Doods, Henri; Treede, Rolf-Detlef; Ceci, Angelo

2016-04-21

The current study assessed whether antidepressant and/or antinociceptive drugs, duloxetine, fluoxetine as well as (±)-8-hydroxy-2-[di-n-propylamino] tetralin (8-OH-DPAT), are able to reverse depression-like behaviour in animals with chronic neuropathic pain. Chronic constriction injury (CCI) of the sciatic nerve in rats was selected as neuropathic pain model. Mechanical hypersensitivity and depression-like behaviour were evaluated 4 weeks after surgery by "electronic algometer" and forced swimming test (FST), which measured the time of immobility, and active behaviours climbing and swimming. The selective noradrenergic and serotonergic uptake blocker duloxetine (20mg/kg) and the selective 5-HT1A agonist 8-OH-DPAT (0.5mg/kg) significantly reversed both mechanical hypersensitivity and depression-like behaviour in CCI animals. Duloxetine significantly reversed depression-like behaviour in CCI rats by increasing the time of climbing and swimming, while 8-OH-DPAT attenuated depression-like behaviour mainly by increasing the time of swimming. However, the selective serotonergic uptake blocker fluoxetine (20mg/kg) failed to attenuate mechanical hypersensitivity and depression-like behaviour, possibly due to confounding pro-nociceptive actions at 5-HT3 receptors. These data suggest to target noradrenergic and 5-HT1A receptors for treatment of chronic pain and its comorbidity depression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Topiramate moderately reduces the motivation to consume alcohol and has a marked antidepressant effect in rats.

PubMed

Hargreaves, Garth A; McGregor, Iain S

2007-11-01

In recent human studies, the anticonvulsant drug topiramate (TPM) has shown efficacy in treating alcohol craving and mood disorders. However, preclinical evidence supporting such effects is surprisingly sparse. Three experiments were conducted here to assess possible anticraving and antidepressant effects of TPM using animal models. In Experiment 1, rats were given 23 weeks ad libitum access to food, water, and either beer (4.44% ethanol v/v) or "near-beer" (a calorie-matched nonalcoholic beer, 0.44% ethanol) in their home cages. They were then restricted to daily 1 hour operant sessions in which they licked for water and either beer or near-beer under a progressive ratio schedule of reinforcement in a lickometer apparatus. The acute effects of TPM on the motivation to consume beer or near-beer were then assessed. The effects of naloxone were also assessed (as a positive control) after TPM testing. In Experiment 2, rats were given 11 weeks of ad libitum home-cage access to food, water, and beer. They then received repeated daily injections of TPM and effects on beer consumption under ad libitum home cage access conditions were monitored. In Experiment 3, the effects of TPM were assessed in the modified Porsolt forced swim test, emergence test, and elevated plus-maze (EPM) using alcohol naïve rats. Topiramate (10, 20, and 40 mg/kg) significantly reduced the motivation to lick for beer, although the maximal effect was moderate in comparison with naloxone (10 mg/kg). However, naloxone, unlike TPM, also reduced responding for near-beer suggesting an alcohol-specific effect of TPM. In Experiment 2, TPM (40 and 80 mg/kg) tended to transiently reduce alcohol consumption in the home cage under ad libitum access but this effect disappeared with repeated administration of the drug. TPM (10 to 80 mg/kg, given twice over 4 hours before test) produced a robust dose-dependent decrease in immobility and increase in active coping strategies in the forced swim test similar to that seen with desipramine (2 x 20 mg/kg). There were modest anxiolytic effects of TPM on the EPM and emergence tests. With acute administration, TPM is moderately effective and relatively selective in reducing the drive to consume alcohol in Wistar rats. This anti-alcohol effect is modest in comparison with naloxone and appears to dissipate under conditions of chronic treatment and ad libitum alcohol access. A marked antidepressant-like effect in the forced swim test and partial anxiolytic effects in other animal models suggests that TPM may be a beneficial treatment for affective disorders. These preliminary results suggest further research is warranted to resolve the mechanisms involved in TPM modulation of both mood and alcohol consumption.

Plyometric Long Jump Training With Progressive Loading Improves Kinetic and Kinematic Swimming Start Parameters.

PubMed

Rebutini, Vanessa Z; Pereira, Gleber; Bohrer, Roberta C D; Ugrinowitsch, Carlos; Rodacki, André L F

2016-09-01

Rebutini, VZ, Pereira, G, Bohrer, RCD, Ugrinowitsch, C, and Rodacki, ALF. Plyometric long jump training with progressive loading improves kinetic and kinematic swimming start parameters. J Strength Cond Res 30(9): 2392-2398, 2016-This study was aimed to determine the effects of a plyometric long jump training program on torque around the lower limb joints and kinetic and kinematics parameters during the swimming jump start. Ten swimmers performed 3 identical assessment sessions, measuring hip and knee muscle extensors during maximal voluntary isometric contraction and kinetic and kinematics parameters during the swimming jump start, at 3 instants: INI (2 weeks before the training program, control period), PRE (2 weeks after INI measurements), and POST (24-48 hours after 9 weeks of training). There were no significant changes from INI to PRE measurements. However, the peak torque and rate of torque development increased significantly from PRE to POST measurements for both hip (47 and 108%) and knee (24 and 41%) joints. There were significant improvements to the horizontal force (7%), impulse (9%), and angle of resultant force (19%). In addition, there were significant improvements to the center of mass displacement (5%), horizontal takeoff velocity (16%), horizontal velocity at water entrance (22%), and peak angle velocity for the knee (15%) and hip joints (16%). Therefore, the plyometric long jump training protocol was effective to enhance torque around the lower limb joints and to control the resultant vector direction, to increase the swimming jump start performance. These findings suggest that coaches should use long jump training instead of vertical jump training to improve swimming start performance.

Swimming of Paramecium in confined channels

NASA Astrophysics Data System (ADS)

Jung, Sunghwan

2012-02-01

Many living organisms in nature have developed a few different swimming modes, presumably derived from hydrodynamic advantage. Paramecium is a ciliated protozoan covered by thousands of cilia with a few nanometers in diameter and tens of micro-meters in length and is able to exhibit both ballistic and meandering motions. First, we characterize ballistic swimming behaviors of ciliated microorganisms in glass capillaries of different diameters and explain the trajectories they trace out. We develop a theoretical model of an undulating sheet with a pressure gradient and discuss how it affects the swimming speed. Secondly, investigation into meandering swimmings within rectangular PDMS channels of dimension smaller than Paramecium length. We find that Paramecium executes a body-bend (an elastic buckling) using the cilia while it meanders. By considering an elastic beam model, we estimate and show the universal profile of forces it exerts on the walls. Finally, we discuss a few other locomotion of Paramecium in other extreme environments like gel.

Effect of three different cultivars of Lepidium meyenii (Maca) on learning and depression in ovariectomized mice

PubMed Central

Rubio, Julio; Caldas, Maria; Dávila, Sonia; Gasco, Manuel; Gonzales, Gustavo F

2006-01-01

Background Lepidium meyenii Walp. (Brassicaceae), known as Maca, is a Peruvian hypocotyl growing exclusively between 4000 and 4500 m altitude in the central Peruvian Andes, particularly in Junin plateau and is used traditionally to enhance fertility. Maca is a cultivated plant and different cultivars are described according to the color of the hypocotyls. Methods The study aimed to elucidate the effect of Yellow, Red and Black Maca on cognitive function and depression in ovariectomized (OVX) mice. In all experiments OVX mice were treated during 21 days and divided in four groups: control group, Yellow Maca, Red Maca and Black Maca. Latent learning was assessed using the water finding task and the antidepressant activity of the three varieties of Maca was evaluated using the forced swimming test. Animals were sacrificed at the end of each treatment and the uterus were excised and weighed. Results Black Maca was the variety that showed the best response in the water finding task, particularly in the trained mice. The three varieties were effective to reduce finding latency in non trained and trained mice (P < 0.05). In the force swimming test, all varieties assessed reduced the time of immobility and increased uterine weight in OVX mice. Conclusion Black Maca appeared to have more beneficial effects on latent learning in OVX mice; meanwhile, all varieties of Maca showed antidepressant activity. PMID:16796734

Carvacrol: from ancient flavoring to neuromodulatory agent.

PubMed

Zotti, Margherita; Colaianna, Marilena; Morgese, Maria Grazia; Tucci, Paolo; Schiavone, Stefania; Avato, Pinarosa; Trabace, Luigia

2013-05-24

Oregano and thyme essential oils are used for therapeutic, aromatic and gastronomic purposes due to their richness in active substances, like carvacrol; however, the effects of the latter on the central nervous system have been poorly investigated. The aim of our study was to define the effects of carvacrol on brain neurochemistry and behavioural outcome in rats. Biogenic amine content in the prefrontal cortex and hippocampus after chronic or acute oral carvacrol administration was measured. Animals were assessed by a forced swimming test. Carvacrol, administered for seven consecutive days (12.5 mg/kg p.o.), was able to increase dopamine and serotonin levels in the prefrontal cortex and hippocampus. When single doses were used (150 and 450 mg/kg p.o.), dopamine content was increased in the prefrontal cortex at both dose levels. On the contrary, a significant dopamine reduction in hippocampus of animals treated with 450 mg/kg of carvacrol was found. Acute carvacrol administration only significantly reduced serotonin content in either the prefrontal cortex or in the hippocampus at the highest dose. Moreover, acute carvacrol was ineffective in producing changes in the forced swimming test. Our data suggest that carvacrol is a brain-active molecule that clearly influences neuronal activity through modulation of neurotransmitters. If regularly ingested in low concentrations, it might determine feelings of well-being and could possibly have positive reinforcer effects.

Association between tryptophan hydroxylase-2 genotype and the antidepressant effect of citalopram and paroxetine on immobility time in the forced swim test in mice.

PubMed

Kulikov, Alexander V; Tikhonova, Maria A; Osipova, Daria V; Kulikov, Victor A; Popova, Nina K

2011-10-01

Tryptophan hydroxylase-2 (TPH2) is the rate limiting enzyme of serotonin synthesis in the brain. The 1473G allele of the C1473G polymorphism in mTPH2 gene is associated with reduced enzyme activity and serotonin synthesis rate in the mouse brain. Here, the influence of the 1473G allele on the antidepressant effect of selective serotonin reuptake inhibitors (SSRIs), citalopram (2.5 or 5.0mg/kg) and paroxetine (5.0 or 10.0mg/kg), in the forced swim test was studied using B6-1473G and B6-1473C congenic mouse lines with the 1473G (decreased TPH2 activity) or 1473C (normal TPH2 activity) alleles, respectively, transferred to the genome of C57BL/6 mouse strain. Paroxetine (5.0 or 10.0mg/kg) and citalopram (2.5 or 5.0mg/kg) decreased immobility time in B6-1473C mice, while both doses of paroxetine and 2.5mg/kg of citaloprame did not alter immobility time in B6-1473G mice. However, 5.0mg/kg of citalopram reduced immobility in B6-1473G mice. The results provided genetic evidence of moderate association between 1473G allele and reduced sensitivity to SSRIs in mice. Copyright © 2011 Elsevier Inc. All rights reserved.

The effects of ifenprodil on the activity of antidepressant drugs in the forced swim test in mice.

PubMed

Poleszak, Ewa; Wośko, Sylwia; Serefko, Anna; Wlaź, Aleksandra; Kasperek, Regina; Dudka, Jarosław; Wróbel, Andrzej; Nowak, Gabriel; Wlaź, Piotr

2014-12-01

According to reports in the literature, more than 30% of depressive patients fail to achieve remission. Therapy with the conventional antidepressant drugs may induce the serious adverse reactions. Moreover, its benefits may be seen at least 2-4 weeks after the first dose. Therefore, the alternative strategies for prevention and treatment of depression are sought. The main aim of our study was to assess the effects of ifenprodil given at a non-active dose (10mg/kg) on the activity of antidepressant agents from diverse pharmacological groups. The antidepressant-like effect was assessed by the forced swim test in mice. Ifenprodil potentiated the antidepressant-like effect of imipramine (15mg/kg) and fluoxetine (5mg/kg) while did not reduce the immobility time of animals which simultaneously received reboxetine (2.5mg/kg) or tianeptine (15mg/kg). The concomitant administration of certain commonly prescribed antidepressant drugs that affect the serotonergic neurotransmission (i.e., typical tricyclic antidepressants and selective serotonin reuptake inhibitors) with a negative modulator selectively binding to the GluN1/N2B subunits of the NMDA receptor complex (i.e., ifenprodil) may induce a more pronounced antidepressant-like effect than monotherapy. However, these findings still need to be confirmed in further experiments. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Fluoxetine, 17-β estradiol or folic acid combined with intra-lateral septal infusions of neuropeptide Y produced antidepressant-like actions in ovariectomized rats forced to swim.

PubMed

Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia

2011-12-01

Folic acid is antidepressant, either alone or combined with several antidepressant drugs. However, the antidepressant-like actions of folic acid combined with intra-lateral septal (LSN) infusions of neuropeptide Y (NPY) in the forced swimming test (FST) have not been tested before. Thus, systemic injections of fluoxetine (20.0mg/kg, P<0.05; s.c.) or 17-β estradiol (10.0 μg/rat, P<0.05; s.c.) or oral administrations of folic acid (50.0 mg/kg, P<0.05; 75.0 mg/kg, P<0.05) or NPY intra-LSN (3.0 μg, P<0.05; 3.5 μg, P<0.05) reduced immobility of ovariectomized Wistar rats. Subthreshold doses of: folic acid (25.0 mg/kg) or 17-β estradiol (5.0 μg/rat, P<0.05) or fluoxetine (15.0 mg/kg, P<0.05; s.c.) combined with subthreshold doses of NPY (2.5 μg/rat, P<0.05; intra-LSN) and these combinations produced antidepressant-like actions; which were canceled by BIBP 3226 (a NPY-Y1 receptor antagonist). It is concluded that folic acid produced antidepressant-like effects probably through the participation of the NPY Y1 receptors found in the lateral septal nuclei. Copyright © 2011 Elsevier Inc. All rights reserved.

Evidences for the agmatine involvement in antidepressant like effect of bupropion in mouse forced swim test.

PubMed

Kotagale, Nandkishor R; Tripathi, Sunil J; Aglawe, Manish M; Chopde, Chandrabhan T; Umekar, Milind J; Taksande, Brijesh G

2013-06-01

Although bupropion has been widely used in the treatment of depression, the precise mechanism of its therapeutic actions is not fully understood. The present study investigated the role of agmatine in an antidepressant like effect of bupropion in mouse forced swim test. The antidepressant like effect of bupropion was potentiated by pretreatment with agmatine (10-20mg/kg, ip) and by the drugs known to increase endogenous agmatine levels in brain viz., l-arginine (40 μg/mouse, icv), an agmatine biosynthetic precursor, ornithine decarboxylase inhibitor, dl-α-difluoromethyl ornithine hydrochloride, DFMO (12.5 μg/mouse, icv), diamine oxidase inhibitor, aminoguanidine (6.5 μg/mouse, icv) and agmatinase inhibitor, arcaine (50 μg/mouse, icv) as well as imidazoline I1 receptor agonists, moxonidine (0.25mg/kg, ip) and clonidine (0.015 mg/kg, ip) and imidazoline I2 receptor agonist, 2-(2-benzofuranyl)-2-imidazoline hydrochloride, 2-BFI (5mg/kg, ip). Conversely, prior administration of I1 receptor antagonist, efaroxan (1mg/kg, ip) and I2 receptor antagonist, idazoxan (0.25mg/kg, ip) blocked the antidepressant like effect of bupropion and its synergistic combination with agmatine. These results demonstrate involvement of agmatine in the antidepressant like effect of bupropion and suggest agmatine and imidazoline receptors as a potential therapeutic target for the treatment of depressive disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

Effect of three different cultivars of Lepidium meyenii (Maca) on learning and depression in ovariectomized mice.

PubMed

Rubio, Julio; Caldas, Maria; Dávila, Sonia; Gasco, Manuel; Gonzales, Gustavo F

2006-06-23

Lepidium meyenii Walp. (Brassicaceae), known as Maca, is a Peruvian hypocotyl growing exclusively between 4000 and 4500 m altitude in the central Peruvian Andes, particularly in Junin plateau and is used traditionally to enhance fertility. Maca is a cultivated plant and different cultivars are described according to the color of the hypocotyls. The study aimed to elucidate the effect of Yellow, Red and Black Maca on cognitive function and depression in ovariectomized (OVX) mice. In all experiments OVX mice were treated during 21 days and divided in four groups: control group, Yellow Maca, Red Maca and Black Maca. Latent learning was assessed using the water finding task and the antidepressant activity of the three varieties of Maca was evaluated using the forced swimming test. Animals were sacrificed at the end of each treatment and the uterus were excised and weighed. Black Maca was the variety that showed the best response in the water finding task, particularly in the trained mice. The three varieties were effective to reduce finding latency in non trained and trained mice (P < 0.05). In the force swimming test, all varieties assessed reduced the time of immobility and increased uterine weight in OVX mice. Black Maca appeared to have more beneficial effects on latent learning in OVX mice; meanwhile, all varieties of Maca showed antidepressant activity.

Role of Prefrontal Cortex Glucocorticoid Receptors in Stress and Emotion

PubMed Central

McKlveen, Jessica M.; Myers, Brent; Flak, Jonathan N.; Bundzikova, Jana; Solomon, Matia B.; Seroogy, Kim B.; Herman, James P.

2013-01-01

Background Stress-related disorders (e.g., depression) are associated with hypothalamic-pituitary-adrenocortical axis dysregulation and prefrontal cortex (PFC) dysfunction, suggesting a functional link between aberrant prefrontal corticosteroid signaling and mood regulation. Methods We used a virally mediated knockdown strategy (short hairpin RNA targeting the glucocorticoid receptor [GR]) to attenuate PFC GR signaling in the rat PFC. Adult male rats received bilateral microinjections of vector control or short hairpin RNA targeting the GR into the prelimbic (n = 44) or infralimbic (n = 52) cortices. Half of the animals from each injection group underwent chronic variable stress, and all were subjected to novel restraint. The first 2 days of chronic variable stress were used to assess depression- and anxiety-like behavior in the forced swim test and open field. Results The GR knockdown confined to the infralimbic PFC caused acute stress hyper-responsiveness, sensitization of stress responses after chronic variable stress, and induced depression-like behavior (increased immobility in the forced swim test). Knockdown of GR in the neighboring prelimbic PFC increased hypothalamic-pituitary-adrenocortical axis responses to acute stress and caused hyper-locomotion in the open field, but did not affect stress sensitization or helplessness behavior. Conclusions The data indicate a marked functional heterogeneity of glucocorticoid action in the PFC and highlight a prominent role for the infralimbic GR in appropriate stress adaptation, emotional control, and mood regulation. PMID:23683655

Long-term effects of controllability or the lack of it on coping abilities and stress resilience in the rat.

PubMed

Lucas, Morgan; Ilin, Yana; Anunu, Rachel; Kehat, Orli; Xu, Lin; Desmedt, Aline; Richter-Levin, Gal

2014-09-01

Findings suggest that stress-induced impaired learning and coping abilities may be attributed more to the psychological nature of the stressor, rather than its physical properties. It has been proposed that establishing controllability over stressors can ameliorate some of its effects on cognition and behavior. Gaining controllability was suggested to be associated with the development of stress resilience. Based on repeated exposure to the two-way shuttle avoidance task, we previously developed and validated a behavioral task that leads to a strict dissociation between gaining controllability (to the level that the associated fear is significantly reduced) and a fearful state of uncontrollability. Employing this protocol, we investigated here the impact of gaining or failing to gain emotional controllability on indices of anxiety and depression and on subsequent abilities to cope with positively or negatively reinforcing learning experiences. In agreement with previous studies, rats exposed to the uncontrollable protocol demonstrated high concentration of sera corticosterone, increased immobility, reduced duration of struggling in the forced swim test and impaired ability to acquire subsequent learning tasks. Achieving emotional controllability resulted in resilience to stress as was indicated by longer duration of struggling in the forced swim test, and enhanced learning abilities. Our prolonged training protocol, with the demonstrated ability of rats to gain emotional controllability, is proposed as a useful tool to study the neurobiological mechanisms of stress resilience.

Involvement of NMDA receptors in the antidepressant-like effect of tramadol in the mouse forced swimming test.

PubMed

Ostadhadi, Sattar; Norouzi-Javidan, Abbas; Chamanara, Mohsen; Akbarian, Reyhaneh; Imran-Khan, Muhammad; Ghasemi, Mehdi; Dehpour, Ahmad-Reza

2017-09-01

Tramadol is an analgesic agent that is mainly used to treat moderate to severe pain. There is evidence that tramadol may have antidepressant property. However, the mechanisms underlying the antidepressant effects of tramadol have not been elucidated yet. Considering that fact that N-methyl-d-aspartate (NMDA) receptor signaling may play an important role in the pathophysiology of depression, the aim of the present study was to investigate the role of NMDA receptor signaling in the possible antidepressant-like effects of tramadol in the mouse forced swimming test (mFST). We found that tramadol exerted antidepressant-like effects at high dose (40mg/kg, intraperitoneally [i.p.]) in the mFST. Co-administration of non-effective doses of NMDA receptor antagonists (ketamine [1mg/kg, i.p.], MK-801 [0.05mg/kg, i.p.], or magnesium sulfate [10mg/kg, i.p.]) with sub-effective dose of tramadol (20mg/kg, i.p.) exerted significant antidepressant-like effects in the mFST. The antidepressant-like effects of tramadol (40mg/kg) was also inhibited by pre-treatment with non-effective dose of the NMDA receptor agonist NMDA (75mg/kg, i.p.). Our data suggest a role for NMDA receptor signaling in the antidepressant-like effects of tramadol in the mFST. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of Ratnaprash for its effect on strength, stamina and fatigue using swim endurance test and biochemical estimation in swiss albino mice

PubMed Central

Gupta, Arun; Kumar, Satyendra; Rajput, Rashmi; Srivastava, Ruchi; Rai, Rajiv K.; Sastry, J. L. N.

2015-01-01

Context: Traditional medicines have been considered as important resources for postponing fatigue, accelerating elimination of fatigue related metabolites and improving physical ability. Rasāyanās or rejuvenative therapies are mentioned as one of the eight clinical specialties in Ayurveda for attaining longevity, healthy life and regulation of bodily balance. Eventhough more detailed studies are needed to confirm the claims of benefits in the light of evidence based research, Ratnaprash, a herbo-mineral rasāyana formulation, is proposed here to be an antifatigue supplement that is good in promoting strength and stamina. Materials and Methods: In the present study, anti fatigue, strength and stamina enhancing properties of Ratnaprash were examined based on swim endurance capacity and the change in biochemical parameters in Swiss Albino mice. Treatment groups were orally administered Ratnaprash at various test doses (500, 1000, 2000 mg/Kg per day), while the control group received distilled water at similar dose volumes. Effect of therapy was evaluated after 28 days of treatment. Results: At the end of study period, the swimming times to exhaustion were longer in the treated groups than in the control group. Plasma lactate levels of treated groups were lower than those of the control group (P < 0.05) while tissue ATP levels were higher. These effects were dose dependent and the strongest effect was seen in groups treated at 1000 mg/Kg. Conclusion: Ratnaprash enhanced the forced swimming capacity of mice and exhibited elevated anti-fatigue activity, reduced blood lactate levels and increased tissue ATP levels in preclinical models in comparison to vehicle control, exhibiting possible role in increasing strength and stamina and contributing anti-fatigue activity. PMID:26600664

Evaluation of Ratnaprash for its effect on strength, stamina and fatigue using swim endurance test and biochemical estimation in swiss albino mice.

PubMed

Gupta, Arun; Kumar, Satyendra; Rajput, Rashmi; Srivastava, Ruchi; Rai, Rajiv K; Sastry, J L N

2015-01-01

Traditional medicines have been considered as important resources for postponing fatigue, accelerating elimination of fatigue related metabolites and improving physical ability. Rasāyanās or rejuvenative therapies are mentioned as one of the eight clinical specialties in Ayurveda for attaining longevity, healthy life and regulation of bodily balance. Eventhough more detailed studies are needed to confirm the claims of benefits in the light of evidence based research, Ratnaprash, a herbo-mineral rasāyana formulation, is proposed here to be an antifatigue supplement that is good in promoting strength and stamina. In the present study, anti fatigue, strength and stamina enhancing properties of Ratnaprash were examined based on swim endurance capacity and the change in biochemical parameters in Swiss Albino mice. Treatment groups were orally administered Ratnaprash at various test doses (500, 1000, 2000 mg/Kg per day), while the control group received distilled water at similar dose volumes. Effect of therapy was evaluated after 28 days of treatment. At the end of study period, the swimming times to exhaustion were longer in the treated groups than in the control group. Plasma lactate levels of treated groups were lower than those of the control group (P < 0.05) while tissue ATP levels were higher. These effects were dose dependent and the strongest effect was seen in groups treated at 1000 mg/Kg. Ratnaprash enhanced the forced swimming capacity of mice and exhibited elevated anti-fatigue activity, reduced blood lactate levels and increased tissue ATP levels in preclinical models in comparison to vehicle control, exhibiting possible role in increasing strength and stamina and contributing anti-fatigue activity.

The Research of the Effect of the Olive Juice on Anxiety and Depression Behavior.

PubMed

Zhang, Jiguo

2015-01-01

In order to evaluate the effect of olive juice on the anxiety and depression behavior, the paper uses olive juice concentrate as experimental material, and uses mice as experimental subjects. Mice are randomly divided into negative, positive, high, medium and low-dose group, administered orally for 7 days. And observe the impact on the mice elevated plus maze test, the opening acts test and forced swim test. The experimental results show that under conditions of the sub-acute administration, olive juice can induce anti-anxiety behavior of mice, but also has the potential to improve depression of mice.

Involvement of nitric oxide-cyclic guanosine monophosphate pathway in the antidepressant-like effect of tropisetron and ondansetron in mice forced swimming test and tail suspension test.

PubMed

Haj-Mirzaian, Arya; Kordjazy, Nastaran; Amiri, Shayan; Haj-Mirzaian, Arvin; Amini-Khoei, Hossien; Ostadhadi, Sattar; Dehpour, AhmadReza

2016-06-05

Antidepressant-like effects of 5-hydroxytryptamine subtype 3 (5-HT3) antagonists including tropisetron and ondansetron have been previously demonstrated in the literature. It was reported that stimulation of 5-HT3 receptors activate the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway, which is involved in regulation of behavioral and emotional functions. In our study, treating animals with tropisetron (5, 10, and 30mg/kg) and ondansetron (0.01 and 0.1µg/kg) significantly decreased the immobility time in forced swimming test (FST) and tail-suspension test (TST). Co-administration of subeffective doses of tropisetron (1mg/kg) and ondansetron (0.001µg/kg) with subeffective dose of l-NAME (10mg/kg, nonselective NO synthase (NOS) inhibitor) and 7-nitroindazole (25mg/kg, neural NOS inhibitor) exerted antidepressant-like effect in FST and TST, while aminoguanidine (50mg/kg, inducible NOS inhibitor) did not enhance the antidepressant-like effect of 5-HT3 antagonists. Besides, l-arginine (750mg/kg, NO precursor) and sildenafil (5mg/kg, phosphodiesterase inhibitor) suppressed the anti-immobility effect of 5-HT3 antagonists. None of the treatments altered the locomotor behavior of mice in open-field test. Also, hippocampal (but not cortical) nitrite level was significantly lower in tropisetron and ondansetron-treated mice compared with saline-injected mice. Also, co-administration of 7-nitroindazole with tropisetron or ondansetron caused a significant decrease in hippocampal nitrite levels. In conclusion, we suggest that antidepressant-like effect of tropisetron and ondansetron are partially mediated by modulation of NO-cGMP pathway. Copyright © 2016. Published by Elsevier B.V.

Extracts of Valeriana officinalis L. s.l. show anxiolytic and antidepressant effects but neither sedative nor myorelaxant properties.

PubMed

Hattesohl, Miguel; Feistel, Björn; Sievers, Hartwig; Lehnfeld, Romanus; Hegger, Mirjam; Winterhoff, Hilke

2008-01-01

Extracts of Valeriana officinalis L. s.l. are used for treating mild sleep disorders and nervous tension. Despite intensive research efforts, the pharmacological actions accounting for the clinical efficacy of valerian remain unclear. Thus, it was the aim of this study to evaluate CNS-related effects of different valerian extracts using behavioral paradigms (mice and rats). Following oral administration two commercially available preparations (extraction solvents: 45% methanol m/m and 70% ethanol v/v), a 35% ethanolic v/v extract and a refined extract derived from it (patented special extract phytofin Valerian 368) were tested for sedative (locomotor activity, ether-induced anaesthesia) and anxiolytic (elevated plus maze) activity. Using the forced swimming and the horizontal wire test the latter two extracts were additionally tested for antidepressant and myorelaxant properties. Up to maximum dosages of 500 or 1000 mg/kg bw none of the valerian extracts displayed sedative effects. Neither spontaneous activity was reduced nor the duration of ether-induced narcosis was prolonged. In contrast, results obtained in the elevated plus maze test revealed a pronounced anxiolytic effect of the 45% methanolic and 35% ethanolic extract as well as of phyotofin Valerian 368 in a dose range of 100-500 mg/kg bw. Additionally and different from its primary extract (35% ethanolic extract) phytofin Valerian 368 showed antidepressant activity in the forced swimming test after subacute treatment. Myorelaxant effects were not observed in dosages up to 1000 mg/kg bw. Due to these findings it is proposed that not sedative but anxiolytic and antidepressant activity, which was elaborated particularly in the special extract phytofin Valerian 368, considerably contribute to the sleep-enhancing properties of valerian.

Evaluation of analgesic, anti-inflammatory, anti-depressant and anti-coagulant properties of Lactuca sativa (CV. Grand Rapids) plant tissues and cell suspension in rats.

PubMed

Ismail, Hammad; Mirza, Bushra

2015-06-27

Lactuca sativa (lettuce) has been traditionally used for relieving pain, inflammation, stomach problems including indigestion and lack of appetite. Moreover, the therapeutic significance of L. sativa includes its anticonvulsant, sedative-hypnotic and antioxidant properties. In the present study, the MC (methanol and chloroform; 1:1) and aqueous extracts of seed and leaf along with cell suspension exudate were prepared. These extracts were explored for their analgesic, anti-inflammatory, antidepressant and anticoagulant effects by hot plate analgesic assay; carrageenan induced hind paw edema test, forced swimming test and capillary method for blood clotting respectively in a rat model. The results were analyzed using one-way Analysis of Variance (ANOVA) followed by Turkey multiple comparison test. Interestingly, the extracts and the cell suspension exudate showed dual inhibition by reducing pain and inflammation. The results indicated that the aqueous extracts of leaf exhibited highest analgesic and anti-inflammatory activities followed by leaf MC, cell suspension exudate, seed aqueous and seed MC extracts. The current findings show that aqueous and MC extracts of seed have the least immobility time in the forced swimming test, which could act as an anti-depressant on the central nervous system. The leaf extracts and cell suspension exudate also expressed moderate anti-depressant activities. In anticoagulant assay, the coagulation time of aspirin (positive control) and MC extract of leaf was comparable, suggesting strong anti-coagulant effect. Additionally, no abnormal behavior or lethality was observed in any animal tested. Taken together, L. sativa can potentially act as a strong herbal drug due to its multiple pharmaceutical effects and is therefore of interest in drug discovery and development of formulations.

NMDA-NO signaling in the dorsal and ventral hippocampus time-dependently modulates the behavioral responses to forced swimming stress.

PubMed

Diniz, Cassiano R A F; Casarotto, Plínio C; Joca, Sâmia R L

2016-07-01

Hodological and genetic differences between dorsal (DH) and ventral (VH) hippocampus may convey distinct behavioral roles. DH is responsible for mediating cognitive process, such as learning and memory, while VH modulates neuroendocrine and emotional-motivational responses to stress. Manipulating glutamatergic NMDA receptors and nitric oxide (NO) systems of the hippocampus induces important changes in behavioral responses to stress. Nevertheless, there is no study concerning functional differences between DH and VH in the modulation of behavioral responses induced by stress models predictive of antidepressant effects. Thus, this study showed that reversible blockade of the DH or VH of animals submitted to the forced swimming test (FST), by using cobalt chloride (calcium-dependent synaptic neurotransmission blocker), was not able to change immobility time. Afterwards, the NMDA-NO system was evaluated in the FST by means of intra-DH or intra-VH administration of NMDA receptor antagonist (AP7), NOS1 and sGC inhibitors (N-PLA and ODQ, respectively). Bilateral intra-DH injections after pretest or before test were able to induce antidepressant-like effects in the FST. On the other hand, bilateral VH administration of AP-7, N-PLA and ODQ induced antidepressant-like effects only when injected before the test. Administration of NO scavenger (C-PTIO) intra-DH, after pretest and before test, or intra-VH before test induced similar results. Increased NOS1 levels was associated to stress exposure in the DH. These results suggest that the glutamatergic-NO system of the DH and VH are both able to modulate behavioral responses in the FST, albeit with differential participation along time after stress exposure. Copyright © 2016 Elsevier B.V. All rights reserved.

Pulmonary function in pubertal synchronized swimmers: 1-year follow-up results and its relation to competitive achievement.

PubMed

Gabrilo, Goran; Peric, Mia; Stipic, Marija

2011-03-01

Pulmonary function (PF) is particularly important in synchronized swimming, considering the characteristics of this sport. However, the sanitizing agents (chlorine) used in pools can have a possible negative influence on the PF parameters. In this study, we observed 24 swimmers (all women, 14 to 16 years of age) and measured their PF and competitive achievement. PF was measured before and after a 1-year period and included standard spirometric variables. Competitive achievement was evidenced during the National Championship. The t-test showed significant increases in body height and weight of the participants and a resulting increase in most of the absolute respiratory flows and pulmonary capacities. Forced vital capacity (FVC) and forced expiratory volume (both in proportion to norm for body height, gender, and age) increased significantly within the study period. FVC significantly predicted the competitive achievement of young swimmers, most probably because artists have to achieve exceptional breath control when upside down underwater. In conclusion, we found no evidence for the eventual negative influence of chlorine and its compounds on the PF of swimmers, and results showed that regular synchronized swim training could improve the PF of young artists.

Effects of 4-hydroxyisoleucine from Fenugreek Seeds on Depression-like Behavior in Socially Isolated Olfactory Bulbectomized Rats

PubMed Central

Kalshetti, Padmaja B.; Alluri, Ramesh; Mohan, Vishwaraman; Thakurdesai, Prasad Arvind

2015-01-01

Context: Antidepressant-like effects of (2S, 3R, 4S)-4-hydroxyisoleucine (4-HI), a major amino acid from fenugreek seeds, has been reported in the animal model of acute depression. Aims: To evaluate effects of subacute administration of 4-HI in animal model of stress-induced depression namely socially isolated olfactory bulbectomized rats. Materials and Methods: Bilateral olfactory bulbectomy (OBX) were induced in 30 Sprague-Dawley rats. After recovery period of 14 days, rats were randomized into five groups of 6 rats each and stressed with social isolation (individual housing). The rats were orally treated with either vehicle (OBX-Iso), positive control, fluoxetine (30 mg/kg) or 4-HI (10, 30, 100 mg/kg) once a day from day 14 onward. Separate group of rats with social isolation but without OBX (Sham-Iso) was also maintained. The behavioral depression and anxiety related parameters using open field test (OFT), sucrose intake test, novelty suppressed feeding (NSF) and forced swim test (FST), and neurochemical estimation (brain monoamines viz., serotonin and nor-adrenaline, serotonin turnover, and serum cortisol) were performed. Statistical Analysis Used: Data was analyzed by either two-way ANOVA (OFT and FST) or one-way ANOVA (sucrose intake test, NSF, and neurochemical estimation) followed by Dunnett's multiple comparisons test. Differences were considered significant at P < 0.05. Results: The significant and dose-dependent protection from behavioral and neurochemical changes were observed in 4-HI co-administrated OBX-Iso rats. Conclusion: 4-HI demonstrated the antidepressant and antianxiety effects in socially isolated stress-induced OBX rats with possible involvement of multiple stress relieving mechanisms. HIGHLIGHTS OF PAPER In this study, the subacute pretreatment of 4-HI showed strong and dose-dependent prevention of isolation stress related behavioral and neurochemical responses in olfactory bulbectomized rats. The prevention of hyperactive HPA axis in OBX-Iso stress-induced rats can be envisaged as probable mechanism of antidepressant and antianxiety effects of 4-HI. SUMMARY Effect of 4-hydroxyisoleucine (4-HI) in olfactory bulbectomized and socially isolated (Iso) rats was evaluated4-HI showed significant and dose-dependent antidepressant effects during novelty suppressed feeding (NSF) and forced swim test (FST)4-HI showed significant and dose-dependent antianxiety effects during OFT (open field test) and sucrose intake test4-HI showed protection from OBX-Iso stress-induced brain monoamines, serotonin turnover, and serum cortisol level elevation. Abbreviations used: SSRI: Selective Serotonin Reuptake Inhibitor; 4-HI: (2S, 3R, 4S)-4-hydroxyisoleucine; OBX: Olfactory bulbectomy; CPCSEA: Committee for the Purpose of Control and Supervision of Experiments on Animals; OFT: Open Field Test; NSF: Novelty Suppressed Feeding; FST: Forced Swimming Test; 5HT: 5-Hydroxytryptamine; 5-HIAA: 5-Hydroxyindoleacetic Acid; NA: Nor-adrenaline; and HPA: Hypothalamic-Pituitary Adrenal. PMID:26929572

Differential involvement of 5-HT(1A) and 5-HT(1B/1D) receptors in human interferon-alpha-induced immobility in the mouse forced swimming test.

PubMed

Zhang, Hongmei; Wang, Wei; Jiang, Zhenzhou; Shang, Jing; Zhang, Luyong

2010-01-01

Although Interferon-alpha (IFN-alpha, CAS 9008-11-1) is a powerful drug in treating several viral infections and certain tumors, a considerable amount of neuropsychiatric side-effects such as depression and anxiety are an unavoidable consequence. Combination with the selective serotonin (5-HT) reuptake inhibitor (SSRI) fluoxetine (CAS 56296-78-7) significantly improved the situation. However, the potential 5-HT(1A) receptor- and 5-HT(1B) receptor-signals involved in the antidepressant effects are still unclear. The effects of 5-HT(1A) receptor- and 5-HT(1B) receptor signals were analyzed by using the mouse forced swimming test (FST), a predictive test of antidepressant-like action. The present results indicated that (1) fluoxetine (administrated intragastrically, 30 mg/kg; not subactive dose: 15 mg/kg) significantly reduced IFN-alpha-induced increase of the immobility time in the forced swimming test; (2) 5-HT(1A) receptor- and 5-HT(1B) receptor ligands alone or in combination had no effects on IFN-alpha-induced increase of the immobility time in the FST; (3) surprisingly, WAY 100635 (5-HT(1A) receptor antagonist, 634908-75-1) and 8-OH-DPAT(5-HT(1A) receptor agonist, CAS 78950-78-4) markedly enhanced the antidepressant effect of fluoxetine at the subactive dose (15 mg/kg, i. g.) on the IFN-alpha-treated mice in the FST. Further investigations showed that fluoxetine combined with WAY 100635 and 8-OH-DPAT failed to produce antidepressant effects in the FST. (4) Co-application of CGS 12066A (5-HT(1B) receptor agonist, CAS 109028-09-3) or GR 127935 (5-HT(1B/1D) receptor antagonist, CAS 148642-42-6) with fluoxetine had no synergistic effects on the IFN-alpha-induced increase of immobility time in FST. (5) Interestingly, co-administration of GR 127935, WAY 100635 and fluoxetine significantly reduced the IFN-alpha-induced increase in immobility time of FST, being more effective than co-administration of WAY 100635 and fluoxetine. All results suggest that (1) compared to the 5-HT(1B) receptor, the 5-HT(1A) receptor signal plays the dominant role in improving the anti-immobility effect of fluoxetine in the IFN-alpha-induced depression; (2) combination of the 5-HT(1A) antagonist with subactive fluoxetine can be helpful in IFN-alpha-induced depression treatment.

On the Hydrodynamics of Anomalocaris Tail Fins.

PubMed

Sheppard, K A; Rival, D E; Caron, J-B

2018-04-25

Anomalocaris canadensis, a soft-bodied stem-group arthropod from the Burgess Shale, is considered the largest predator of the Cambrian period. Thanks to a series of lateral flexible lobes along its dorso-ventrally compressed body, it is generally regarded as an efficient swimmer, well-adapted to its predatory lifestyle. Previous theoretical hydrodynamic simulations have suggested a possible optimum in swimming performance when the lateral lobes performed as a single undulatory lateral fin, comparable to the pectoral fins in skates and rays. However, the role of the unusual fan-like tail of Anomalocaris has not been previously explored. Swimming efficiency and maneuverability deduced from direct hydrodynamic analysis are here studied in a towing tank facility using a three-vane physical model designed as an abstraction of the tail fin. Through direct force measurements, it was found that the model exhibited a region of steady-state lift and drag enhancement at angles of attack greater than 25° when compared to a triangular-shaped reference model. This would suggest that the resultant normal force on the tail fin of Anomalocaris made it well-suited for turning maneuvers, giving it the ability to turn quickly and through small radii of curvature. These results are consistent with an active predatory lifestyle, although detailed kinematic studies integrating the full organism, including the lateral lobes, would be required to test the effect of the tail fin on overall swimming performance. This study also highlights a possible example of evolutionary convergence between the tails of Anomalocaris and birds, which, in both cases, are well-adapted to efficient turning maneuvers.

Harmane induces anxiolysis and antidepressant-like effects in rats.

PubMed

Aricioglu, Feyza; Altunbas, Hale

2003-12-01

A forced swim test (FST) and an elevated plus maze (EPM) were used to determine antidepressant and anxiolytic effects of harmane in rats in comparison with a known antidepressant, imipramine (30 mg/kg i.p.). Harmane (2.5, 5.0, or 10 mg/kg, i.p.), saline, or imipramine were given 30 minutes before the tests. Administration of harmane decreased the time of immobility in the FST dose-dependently and increased the time spent in open arms in the EPM, as compared with the saline group. As an endogenous substance, harmane therefore has anti-anxiety and antidepressant effects.

Butterfly Sprint Swimming Technique, Analysis of Somatic and Spatial-Temporal Coordination Variables

PubMed Central

Stanula, Arkadiusz; Krężałek, Piotr; Ostrowski, Andrzej; Kaca, Marcin; Głąb, Grzegorz

2017-01-01

Abstract The aim of this study was to investigate somatic properties and force production of leg extensor muscles measured in the countermovement jump test (CMJ), as well as to analyse kinematic variables of sprint surface butterfly swimming. Thirty-four male competitive swimmers were recruited with an average age of 19.3 ± 1.83 years. Their average body height (BH) was 183.7 ± 5.93 cm, body fat content 10.8 ± 2.64% and body mass (BM) 78.3 ± 5.0 kg. Length measurements of particular body segments were taken and a counter movement jump (CMJ) as well as an all-out 50 m butterfly speed test were completed. The underwater movements of the swimmers’ bodies were recorded with a digital camera providing side-shots. We registered a significant relationship between body mass (r = 0.46), lean body mass (r = 0.48) and sprint surface butterfly swimming (VSBF). The anaerobic power measured in the CMJ test, total body length (TBL) as well as upper and lower extremity length indices did not influence swimming speed significantly. The temporal entry-kick index (the time ratio between the first kick and arm entry) significantly influenced VSBF (r = -0.45). Similarly, medium power of the coefficient was indicated between a) stroke rate kinematics (SR), b) duration of the first leg kick (LP1), c) air phase duration of arm recovery (Fly-arm), and VSBF (r = 0.40; r = 0.40 and r = 0.41, respectively). The entry-kick temporal index showed that, in the butterfly cycle, an appropriately early executed initial kick when compared to arm entry was associated with a longer arm propulsion phase, which in turn was associated with minimizing resistive gliding phases and enabled relatively longer and less resistive air arm recovery (higher value of the fly-arm index). The higher value of SR kinematic was another important element of the best butterfly results in this study. PMID:29339985

Chemotactic Motility of Sperm in Shear

NASA Astrophysics Data System (ADS)

Guasto, Jeffrey S.; Riffell, Jeffrey A.; Zimmer, Richard K.; Stocker, Roman

2011-11-01

Chemical gradients are utilized by plants and animals in sexual reproduction to guide swimming sperm cells toward the egg. This process (``chemotaxis''), which can greatly increase the success of fertilization, is subject to interference by fluid flow, both in the bodily conduits of internal fertilizers (e.g. mammals) and in the aquatic environment of external fertilizers (e.g. benthic invertebrates). We studied the biomechanics of chemotaxing sea urchin spermatozoa using microfluidic devices, which allow for the precise and independent control of attractant gradients and fluid shear. We captured swimming trajectories and flagellar beat patterns using high-speed video-microscopy, to detect chemotactic responses and measure the effect of fluid forces on swimming. This work will ultimately help us to understand how swimming sperm cells actively navigate natural chemoattractant gradients for successful fertilization.

High post-partum levels of corticosterone given to dams influence postnatal hippocampal cell proliferation and behavior of offspring: A model of post-partum stress and possible depression.

PubMed

Brummelte, Susanne; Pawluski, Jodi L; Galea, Liisa A M

2006-09-01

Post-partum stress and depression (PPD) have a significant effect on child development and behavior. Depression is associated with hypercortisolism in humans, and the fluctuating levels of hormones, including corticosterone, during pregnancy and the post-partum, may contribute to PPD. The present study was developed to investigate the effects of high-level corticosterone (CORT) post-partum in the mother on postnatal neurogenesis and behavior in the offspring. Sprague-Dawley dams were treated with either CORT (40 mg/kg) or sesame oil injections daily for 26 days beginning the day after giving birth. Dams were tested in the forced swim test (FST) and in the open field test (OFT) on days 24-26 post-partum. Results showed that the dams exposed to CORT expressed "depressive-like" behavior compared to controls, with decreased struggling behavior and increased immobility in the FST. To investigate the effects of treatment on hippocampal postnatal cell proliferation and survival in the offspring, males and females from treated dams were injected with BrdU (50 mg/kg) on postnatal day 21 and perfused either 24 h (cell proliferation) or 21 days (cell survival) later. Furthermore, male and female offspring from each litter were tested in adulthood on various behavioral tests, including the forced swim test, open field test, resistance to capture test and elevated plus maze. Intriguingly, male, but not female, offspring of CORT-treated dams exhibited decreased postnatal cell proliferation in the dentate gyrus. Both male and female offspring of CORT-treated dams showed higher resistance to capture and greater locomotor activity as assessed in the open field test. As high levels of CORT may be a characteristic of stress and/or depression, these findings support a model of 'CORT-induced' post-partum stress and possibly depression and demonstrate that the offspring of affected dams can exhibit changes in postnatal neurogenesis and behavior in adulthood.

Unsteady propulsion by an intermittent swimming gait

NASA Astrophysics Data System (ADS)

Akoz, Emre; Moored, Keith W.

2018-01-01

Inviscid computational results are presented on a self-propelled swimmer modeled as a virtual body combined with a two-dimensional hydrofoil pitching intermittently about its leading edge. Lighthill (1971) originally proposed that this burst-and-coast behavior can save fish energy during swimming by taking advantage of the viscous Bone-Lighthill boundary layer thinning mechanism. Here, an additional inviscid Garrick mechanism is discovered that allows swimmers to control the ratio of their added mass thrust-producing forces to their circulatory drag-inducing forces by decreasing their duty cycle, DC, of locomotion. This mechanism can save intermittent swimmers as much as 60% of the energy it takes to swim continuously at the same speed. The inviscid energy savings are shown to increase with increasing amplitude of motion, increase with decreasing Lighthill number, Li, and switch to an energetic cost above continuous swimming for sufficiently low DC. Intermittent swimmers are observed to shed four vortices per cycle that form into groups that are self-similar with the DC. In addition, previous thrust and power scaling laws of continuous self-propelled swimming are further generalized to include intermittent swimming. The key is that by averaging the thrust and power coefficients over only the bursting period then the intermittent problem can be transformed into a continuous one. Furthermore, the intermittent thrust and power scaling relations are extended to predict the mean speed and cost of transport of swimmers. By tuning a few coefficients with a handful of simulations these self-propelled relations can become predictive. In the current study, the mean speed and cost of transport are predicted to within 3% and 18% of their full-scale values by using these relations.

A comparative pharmacological investigation of three samples of 'Guduchi ghrita' for adaptogenic activity against forced swimming induced gastric ulceration and hematological changes in albino rats

PubMed Central

Savrikar, Shriram S.; Dole, Vilas; Ravishankar, B.; Shukla, Vinay J.

2010-01-01

This study was undertaken to investigate the impact of formulation factors and adjuvants on the expression of biological activity of Tinospora cordifolia (Willd.) Miers. The adaptogenic effect of three samples of Guduchi ghrita, prepared using plain ghee (clarified butter) obtained from three different sources was studied in albino rats and compared with expressed juice of stem of Guduchi. The test preparations were evaluated against forced–swimming induced hypothermia, gastric ulceration and changes in the hematological parameters. The test drug given in the form of 'ghrita' produced better effect in comparison to the expressed juice. Among the three 'ghrita' preparations evaluated, only the 'Solapur Guduchi ghrita' (SGG) was found to produce significant inhibition of stress hypothermia and gastric ulceration. The other two preparations 'Nanded Guduchi ghrita' (NGG), and 'Wardha Guduchi ghrita' (WGG) could produce only a marginal effect. In hematological parameters 'Guduchi' juice produced better reversal of the stress-induced changes in comparison to the test 'ghrita' preparations. The present study provides evidence highlighting the importance of formulation factors for the expression of biological activity. PMID:20814518

Hypobaric Hypoxia Induces Depression-like Behavior in Female Sprague-Dawley Rats, but not in Males

PubMed Central

Bogdanova, Olena V.; Olson, Paul R.; Sung, Young-Hoon; D'Anci, Kristen E.; Renshaw, Perry F.

2015-01-01

Abstract Kanekar, Shami, Olena V. Bogdanova, Paul R. Olson, Young-Hoon Sung, Kristen E. D'Anci, and Perry F. Renshaw. Hypobaric hypoxia induces depression-like behavior in female Sprague-Dawley rats, but not males. High Alt Med Biol 16:52–60, 2015—Rates of depression and suicide are higher in people living at altitude, and in those with chronic hypoxic disorders like asthma, chronic obstructive pulmonary disorder (COPD), and smoking. Living at altitude exposes people to hypobaric hypoxia, which can lower rat brain serotonin levels, and impair brain bioenergetics in both humans and rats. We therefore examined the effect of hypobaric hypoxia on depression-like behavior in rats. After a week of housing at simulated altitudes of 20,000 ft, 10,000 ft, or sea level, or at local conditions of 4500 ft (Salt Lake City, UT), Sprague Dawley rats were tested for depression-like behavior in the forced swim test (FST). Time spent swimming, climbing, or immobile, and latency to immobility were measured. Female rats housed at altitude display more depression-like behavior in the FST, with significantly more immobility, less swimming, and lower latency to immobility than those at sea level. In contrast, males in all four altitude groups were similar in their FST behavior. Locomotor behavior in the open field test did not change with altitude, thus validating immobility in the FST as depression-like behavior. Hypobaric hypoxia exposure therefore induces depression-like behavior in female rats, but not in males. PMID:25803141

Antistress and antioxidant effects of virgin coconut oil in vivo.

PubMed

Yeap, Swee Keong; Beh, Boon Kee; Ali, Norlaily Mohd; Yusof, Hamidah Mohd; Ho, Wan Yong; Koh, Soo Peng; Alitheen, Noorjahan Banu; Long, Kamariah

2015-01-01

Virgin coconut oil (VCO) has been consumed worldwide for various health-related reasons and some of its benefits have been scientifically evaluated. Medium-chain fatty acids were found to be a potential antidepressant functional food; however, this effect had not been evaluated in VCO, which is rich in polyphenols and medium-chain fatty acids. The aim of this study was to evaluate the antistress and antioxidant effects of VCO in vivo , using mice with stress-induced injury. The antistress effect of VCO (administered per os , at a dose of 10 ml/kg body weight) was evaluated using the forced swim test and chronic cold restraint stress models. VCO was able to reduce immobility time and restore oxidative stress in mice post-swim test. Furthermore, mice treated with VCO were found to exhibit higher levels of brain antioxidants, lower levels of brain 5-hydroxytryptamine and reduced weight of the adrenal glands. Consequently, the serum cholesterol, triglyceride, glucose and corticosterone levels were also lower in VCO-treated mice. These results suggest the potential value of VCO as an antistress functional oil.

Antistress and antioxidant effects of virgin coconut oil in vivo

PubMed Central

YEAP, SWEE KEONG; BEH, BOON KEE; ALI, NORLAILY MOHD; YUSOF, HAMIDAH MOHD; HO, WAN YONG; KOH, SOO PENG; ALITHEEN, NOORJAHAN BANU; LONG, KAMARIAH

2015-01-01

Virgin coconut oil (VCO) has been consumed worldwide for various health-related reasons and some of its benefits have been scientifically evaluated. Medium-chain fatty acids were found to be a potential antidepressant functional food; however, this effect had not been evaluated in VCO, which is rich in polyphenols and medium-chain fatty acids. The aim of this study was to evaluate the antistress and antioxidant effects of VCO in vivo, using mice with stress-induced injury. The antistress effect of VCO (administered per os, at a dose of 10 ml/kg body weight) was evaluated using the forced swim test and chronic cold restraint stress models. VCO was able to reduce immobility time and restore oxidative stress in mice post-swim test. Furthermore, mice treated with VCO were found to exhibit higher levels of brain antioxidants, lower levels of brain 5-hydroxytryptamine and reduced weight of the adrenal glands. Consequently, the serum cholesterol, triglyceride, glucose and corticosterone levels were also lower in VCO-treated mice. These results suggest the potential value of VCO as an antistress functional oil. PMID:25452773

Despair-associated memory requires a slow-onset CA1 long-term potentiation with unique underlying mechanisms

PubMed Central

Jing, Liang; Duan, Ting-Ting; Tian, Meng; Yuan, Qiang; Tan, Ji-Wei; Zhu, Yong-Yong; Ding, Ze-Yang; Cao, Jun; Yang, Yue-Xiong; Zhang, Xia; Mao, Rong-Rong; Richter-levin, Gal; Zhou, Qi-Xin; Xu, Lin

2015-01-01

The emotion of despair that occurs with uncontrollable stressful event is probably retained by memory, termed despair-associated memory, although little is known about the underlying mechanisms. Here, we report that forced swimming (FS) with no hope to escape, but not hopefully escapable swimming (ES), enhances hippocampal α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)-dependent GluA1 Ser831 phosphorylation (S831-P), induces a slow-onset CA1 long-term potentiation (LTP) in freely moving rats and leads to increased test immobility 24-h later. Before FS application of the antagonists to block S831-P or N-methyl-D-aspartic acid receptor (NMDAR) or glucocorticoid receptor (GR) disrupts LTP and reduces test immobility, to levels similar to those of the ES group. Because these mechanisms are specifically linked with the hopeless of escape from FS, we suggest that despair-associated memory occurs with an endogenous CA1 LTP that is intriguingly mediated by a unique combination of rapid S831-P with NMDAR and GR activation to shape subsequent behavioral despair. PMID:26449319

Effect of swim exercise training on human muscle fiber function

NASA Technical Reports Server (NTRS)

Fitts, R. H.; Costill, D. L.; Gardetto, P. R.

1989-01-01

The effect of swim exercise training on the human muscle fiber function was investigated in swimmers trained in a typical collegiate swim-training program followed by an intensified 10-day training period. The measured parameters included the peak tension (P0), negative log molar Ca(2+) concentration (pCa)-force, and maximal shortening speed (Vmax) of the slow-twitch type I and fast-twitch type II fibers obtained by biopsy from the deltoid muscle. The P0 values were found to be not altered after either the training or the 10-day intensive program. The type I fibers from the trained swimmers showed pCa-force curves shifted to the right, such that higher free Ca(2+) levels were required to elicit a given percent of P0. The training program significantly increased the Vmax in the type I fibers and decreased that of the type II fibers, and the 10-day intensive training produced a further significant decrease of the type II fibers.

Predicting the buoyancy, equilibrium and potential swimming ability of giraffes by computational analysis.

PubMed

Henderson, Donald M; Naish, Darren

2010-07-21

Giraffes (Giraffa camelopardalis) are often stated to be unable to swim, and while few observations supporting this have ever been offered, we sought to test the hypothesis that giraffes exhibited a body shape or density unsuited for locomotion in water. We assessed the floating capability of giraffes by simulating their buoyancy with a three-dimensional mathematical/computational model. A similar model of a horse (Equus caballus) was used as a control, and its floating behaviour replicates the observed orientations of immersed horses. The floating giraffe model has its neck sub-horizontal, and the animal would struggle to keep its head clear of the water surface. Using an isometrically scaled-down giraffe model with a total mass equal to that of the horse, the giraffe's proportionally larger limbs have much higher rotational inertias than do those of horses, and their wetted surface areas are 13.5% greater relative to that of the horse, thus making rapid swimming motions more strenuous. The mean density of the giraffe model (960 gm/l) is also higher than that of the horse (930 gm/l), and closer to that causing negative buoyancy (1000 gm/l). A swimming giraffe - forced into a posture where the neck is sub-horizontal and with a thorax that is pulled downwards by the large fore limbs - would not be able to move the neck and limbs synchronously as giraffes do when moving on land, possibly further hampering the animal's ability to move its limbs effectively underwater. We found that a full-sized, adult giraffe will become buoyant in water deeper than 2.8m. While it is not impossible for giraffes to swim, we speculate that they would perform poorly compared to other mammals and are hence likely to avoid swimming if possible. (c) 2010. Published by Elsevier Ltd. All rights reserved.

Identification of Personality Differences among Various Swimming Ability Groups by Sex. Final Report. CORD Project.

ERIC Educational Resources Information Center

Davis, Michael G.; Stewart, Charles W.

This study investigates 16 personality factors and their relevance to the swimming proficiency of physical education students at Wisconsin State University-River Falls. Two instruments, a swimming skills test and the Cattell Sixteen Personality Factor Questionnaire, were utilized. The major hypotheses tested include: (1) there is no difference…

Neuropharmacological effects of oleamide in male and female mice.

PubMed

Akanmu, Moses A; Adeosun, Samuel O; Ilesanmi, Olapade R

2007-08-22

Oleamide, a fatty acid amide accumulates selectively in the cerebrospinal fluid of sleep deprived cats and rats. Oleamide has been reported to have effects on a wide range of receptors and neurotransmitter systems especially the centrally acting ones for example, dopamine acetylcholine, serotonin, gamma aminobutyric acid (GABA), cannabinoid and vanilloid among others. This suggests a wide range of central nervous system effects of the compound. The effects of intraperitoneal administered oleamide on Novelty-induced behaviours, learning and memory and forced swimming-induced depression were studied. The relative effects of the compound on the male and female mice were also noted. Oleamide dose-dependently reduced (p<0.05) novelty induced rearing, grooming and locomotion. The effects on the all NIBs started within the first 10 min of the test and the peak of the effects was observed during the third 10 min period of the test. Effect of oleamide on short-term working memory was significantly (p<0.05) affected only with the dose of 5mg/kg while the other dose of 10mg/kg had no effect. In the forced swimming test, acute triple intraperitoneal administration of oleamide at 10mg/kg induced a significant reduction in the immobility duration in mice signifying an antidepressant effect. Sex differences in the effects of oleamide (10mg/kg, i.p.) were clearly evident in active behaviours in FST. These results confirm the multiplicity of central nervous system receptors and neurotransmitters that oleamide interacts with hence its numerous and diverse neuropharmacological effects. Most importantly, the present study suggests that oleamide has antidepressant-like property.

Highly palatable food access during adolescence increased anxiety-/depression-like behaviors in male, but not in female, rats.

PubMed

Kim, Jin Young; Kim, Doyun; Park, Kyungpyo; Lee, Jong-Ho; Jahng, Jeong Won

2017-04-11

This study was conducted to examine the sexual dimorphic effects of highly palatable food (HPF) access during adolescence on the neurochemistry and depression-/anxiety-like behaviors of rats. Male and female Sprague-Dawley pups had free access to chocolate cookie rich in fat (HPF) from postnatal day 28 in addition to ad libitum chow, and the control groups received only chow. The food conditions were continued throughout the entire experimental period, and the neurochemical and behavioral measurements were performed during young adulthood. Rats were subjected to the ambulatory activity, elevated plus maze, and forced swim tests. Corticosterone levels during 2 h of restraint stress were analyzed with radioimmunoassay, and ΔFosB and brain-derived neurotrophic factor (BDNF) expression in the nucleus accumbens (NAc) with Western blot analysis. Cookie access did not affect body weight gain and total caloric intake in both sexes; however, it increased retroperitoneal fat depot only in males. The time spent in open arms during elevated plus maze test was decreased and immobility during forced swim test was increased in cookie-fed males, but not in cookie-fed females. Main effect of food condition on the stress-induced corticosterone increase was observed in males, but not in females, and cookie access increased BDNF expression in the NAc only in males. Increased BDNF expression in the NAc and fat depot, in addition to the stress axis dysfunction, may play roles in the pathophysiology of depression- and/or anxiety-like behaviors induced by cookie access.

Social defeat stress induces a depression-like phenotype in adolescent male c57BL/6 mice.

PubMed

Iñiguez, Sergio D; Riggs, Lace M; Nieto, Steven J; Dayrit, Genesis; Zamora, Norma N; Shawhan, Kristi L; Cruz, Bryan; Warren, Brandon L

2014-05-01

Abstract Exposure to stress is highly correlated with the emergence of mood-related illnesses. Because major depressive disorder often emerges in adolescence, we assessed the effects of social defeat stress on responses to depressive-like behaviors in juvenile mice. To do this, postnatal day (PD) 35 male c57BL/6 mice were exposed to 10 days of social defeat stress (PD35-44), while control mice were handled daily. Twenty-four hours after the last episode of defeat (PD45), separate groups of mice were tested in the social interaction, forced swimming, sucrose preference, and elevated plus-maze behavioral assays (n = 7-12 per group). Also, we examined body weight gain across days of social defeat and levels of blood serum corticosterone 40 min after the last episode of defeat stress. Our data indicates that defeated mice exhibited a depressive-like phenotype as inferred from increased social avoidance, increased immobility in the forced swim test, and reduced sucrose preference (a measure of anhedonia), when compared to non-defeated controls. Defeated mice also displayed an anxiogenic-like phenotype when tested on the elevated plus-maze. Lastly, stressed mice displayed lower body weight gain, along with increased blood serum corticosterone levels, when compared to non-stressed controls. Overall, we show that in adolescent male c57BL/6 mice, social defeat stress induces a depression- and anxiety-like phenotype 24 h after the last episode of stress. These data suggest that the social defeat paradigm may be used to examine the etiology of stress-induced mood-related disorders during adolescence.

Social defeat stress induces a depression-like phenotype in adolescent male c57BL/6 mice

PubMed Central

Iñiguez, Sergio D.; Riggs, Lace M.; Nieto, Steven J.; Dayrit, Genesis; Zamora, Norma N.; Shawhan, Kristi L.; Cruz, Bryan; Warren, Brandon L.

2016-01-01

Exposure to stress is highly correlated with the emergence of mood-related illnesses. Because major depressive disorder often emerges in adolescence, we assessed the effects of social defeat stress on responses to depressive-like behaviors in juvenile mice. To do this, postnatal day (PD) 35 male c57BL/6 mice were exposed to 10 days of social defeat stress (PD35–44), while control mice were handled daily. Twenty-four hours after the last episode of defeat (PD45), separate groups of mice were tested in the social interaction, forced swimming, sucrose preference, and elevated plus-maze behavioral assays (n = 7–12 per group). Also, we examined body weight gain across days of social defeat and levels of blood serum corticosterone 40 min after the last episode of defeat stress. Our data indicates that defeated mice exhibited a depressive-like phenotype as inferred from increased social avoidance, increased immobility in the forced swim test, and reduced sucrose preference (a measure of anhedonia), when compared to non-defeated controls. Defeated mice also displayed an anxiogenic-like phenotype when tested on the elevated plus-maze. Lastly, stressed mice displayed lower body weight gain, along with increased blood serum corticosterone levels, when compared to non-stressed controls. Overall, we show that in adolescent male c57BL/6 mice, social defeat stress induces a depression- and anxiety-like phenotype 24 h after the last episode of stress. These data suggest that the social defeat paradigm may be used to examine the etiology of stress-induced mood-related disorders during adolescence. PMID:24689732

Acute administration of fluoxetine normalizes rapid eye movement sleep abnormality, but not depressive behaviors in olfactory bulbectomized rats.

PubMed

Wang, Yi-Qun; Tu, Zhi-Cai; Xu, Xing-Yuan; Li, Rui; Qu, Wei-Min; Urade, Yoshihiro; Huang, Zhi-Li

2012-01-01

In humans, depression is associated with altered rapid eye movement (REM) sleep. However, the exact nature of the relationship between depressive behaviors and sleep abnormalities is debated. In this study, bilateral olfactory bulbectomy (OBX) was carried out to create a model of depression in rats. The sleep-wake profiles were assayed using a cutting-edge sleep bioassay system, and depressive behaviors were evaluated by open field and forced swimming tests. The monoamine content and monoamine metabolite levels in the brain were determined by a HPLC-electrochemical detection system. OBX rats exhibited a significant increase in REM sleep, especially between 15:00 and 18:00 hours during the light period. Acute treatment with fluoxetine (10 mg/kg, i.p.) immediately abolished the OBX-induced increase in REM sleep, but hyperactivity in the open field test and the time spent immobile in the forced swimming test remained unchanged. Neurochemistry studies revealed that acute administration of fluoxetine increased serotonin (5-HT) levels in the hippocampus, thalamus, and midbrain and decreased levels of the 5-HT metabolite 5-hydroxyindoleacetic acid (5-HIAA). The ratio of 5-HIAA to 5-HT decreased in almost all regions of the brain. These results indicate that acute administration of fluoxetine can reduce the increase in REM sleep but does not change the depressive behaviors in OBX rats, suggesting that there was no causality between REM sleep abnormalities and depressive behaviors in OBX rats. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

Sex and age differences in the antidepressant-like effect of fluoxetine in the forced swim test.

PubMed

Fernández-Guasti, Alonso; Olivares-Nazario, Maribel; Reyes, Rebeca; Martínez-Mota, Lucía

2017-01-01

This study compared in males and females of three representative ages: young adults (3-5months old), middle-aged (12-15months old) and senescent (23-25months old) the antidepressant-like effect of fluoxetine (FLX, 5.0 and 10mg/kg) in the forced swim test (FST). Intact (non gonadectomized) rats were evaluated. Young adult females were chosen in proestrus/estrus or in metestrus/diestrus, while middle-aged and senescent females were selected in metestrus/diestrus. Locomotion and motor coordination were also recorded. Under basal conditions (without FLX), young adult and middle-aged females showed less immobility than males. This sex difference disappeared at senescence because males diminished their levels of immobility. Thus, senescent males showed lower immobility than middle-aged and young males. FLX (5 and 10mg/kg) produced similar actions in young females irrespective of their estrous cycle phase, therefore, these subgroups were pooled in a single one. Young adult and middle aged females clearly responded to 5 and 10mg/kg of FLX with a reduction in immobility, while young adult and middle-aged males only did to 10mg/kg. In senescent females 10mg/kg FLX reduced immobility. Remarkably, in senescent males this FLX dose did not produce an antidepressant-like effect. FLX marginally affected locomotion; however, at its highest dose (10mg/kg), and only in senescent males, interfered with motor coordination tested in the rotarod. These data show that sex and aging influence behavioral despair without treatment and after FLX. Copyright © 2016 Elsevier Inc. All rights reserved.

Strain differences in paroxetine-induced reduction of immobility time in the forced swimming test in mice: role of serotonin.

PubMed

Guzzetti, Sara; Calcagno, Eleonora; Canetta, Alessandro; Sacchetti, Giuseppina; Fracasso, Claudia; Caccia, Silvio; Cervo, Luigi; Invernizzi, Roberto W

2008-10-10

We studied the antidepressant-like effect of paroxetine in strains of mice carrying different isoforms of tryptophan hydroxylase-2 (TPH-2), the enzyme responsible for the synthesis of brain serotonin (5-HT). The effect of paroxetine alone and in combination with pharmacological treatments enhancing or lowering 5-HT synthesis or melatonin was assessed in the forced swimming test in mice carrying allelic variants of TPH-2 (1473C in C57BL/6 and 1473G in DBA/2 and BALB/c). Changes in brain 5-hydroxytryptophan (5-HTP) accumulation and melatonin levels were measured by high-performance liquid chromatography. Paroxetine (2.5 and 5 mg/kg) reduced immobility time in C57BL/6J and C57BL/6N mice but had no such effect in DBA/2J, DBA/2N and BALB/c mice, even at 10 mg/kg. Enhancing 5-HT synthesis with tryptophan reinstated the antidepressant-like effect of paroxetine in DBA/2J, DBA/2N and BALB/c mice whereas inhibition of 5-HT synthesis prevented the effect of paroxetine in C57BL/6N mice. The response to paroxetine was not associated with changes in locomotor activity, brain melatonin or brain levels of the drug measured at the end of the behavioral test. These results support the importance of 5-HT synthesis in the response to SSRIs and suggest that melatonin does not contribute to the ability of tryptophan to rescue the antidepressant-like effect of paroxetine.

AMPAkines have novel analgesic properties in rat models of persistent neuropathic and inflammatory pain.

PubMed

Le, Alexander M; Lee, Michelle; Su, Chen; Zou, Anthony; Wang, Jing

2014-11-01

Novel analgesics that do not suppress the respiratory drive are urgently needed. Glutamate signaling through α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors plays important roles in central pain circuits. AMPAkines augment AMPA receptor function and have been shown to stimulate the respiratory drive to oppose opioid-induced hypoventilation. However, their role in chronic pain states remains unknown. The authors studied AMPAkines (CX546 and CX516) in rat spared nerve injury (SNI) model of neuropathic pain and Complete Freund's Adjuvant (CFA) model of inflammatory pain. They measured the effect of AMPAkines on mechanical and cold allodynia. They also evaluated their effect on depressive symptoms of pain using the forced swim test, as time of immobility on this test has been used as a measure for behavioral despair, a feature of depression. The authors found that CX546, compared with dimethyl sulfoxide (DMSO) control, reduced both mechanical and sensory allodynia in SNI (DMSO group, n = 9; CX546 group, n = 11) and CFA models (both DMSO and CX546 groups, n = 9). They found that CX546, compared with control, also reduced depressive symptoms of pain by decreasing immobility on the forced swim test in both SNI (both DMSO and CX546 groups, n = 8) and CFA models (both DMSO and CX546 groups, n = 10). Finally, they found that CX516, compared with control, also reduced mechanical and cold allodynia in the SNI model (both DMSO and CX516 groups, n = 10). AMPAkines alleviate pain hypersensitivity as well as depression-like behavior associated with long-lasting nerve injury and inflammatory insult.

The influence of caffeine on the activity of moclobemide, venlafaxine, bupropion and milnacipran in the forced swim test in mice.

PubMed

Poleszak, Ewa; Szopa, Aleksandra; Wyska, Elżbieta; Wośko, Sylwia; Serefko, Anna; Wlaź, Aleksandra; Pieróg, Mateusz; Wróbel, Andrzej; Wlaź, Piotr

2015-09-01

Worrying data indicate that excessive caffeine intake applies to patients suffering from mental disorders, including depression. It is thus possible to demonstrate the usefulness of caffeine and its derivatives in the treatment of depression. The main goal of the present studywas to evaluate the influence of caffeine (5mg/kg) on the activity of moclobemide (1.5 mg/kg), venlafaxine (1 mg/kg), bupropion (10 mg/kg), and milnacipran (1.25 mg/kg). Moreover, we assessed the influence of caffeine on their serum and brain levels using highperformance liquid chromatography. The experiment was carried out on naïve adult male Albino Swiss mice. Caffeine and tested drugs were administered intraperitoneally. The influence of caffeine on the activity of selected antidepressant drugs was evaluated in forced swim test (FST). Locomotor activity was estimated to verify and exclude false positive/negative results. To assess the influence of caffeine on the levels of studied antidepressant drugs, their concentrations were determined in murine serum and brains using high-performance liquid chromatography. Caffeine potentiated activity of all antidepressants examined in FST and the observed effects were not due to the increase in locomotor activity in the animals. Only in the case of co-administration of caffeine and milnacipran an increased milnacipran concentration in serum was observed without affecting its concentration in the brain. Caffeine potentiates the activity of antidepressant drugs from different chemical groups. The interactions of caffeine with venlafaxine, bupropion and moclobemide occur in pharmacodynamic phase, whereas the interaction of caffeine–milnacipran occurs, at least partially, in pharmacokinetic phase.

Swimming speed alteration of Artemia sp. and Brachionus plicatilis as a sub-lethal behavioural end-point for ecotoxicological surveys.

PubMed

Garaventa, Francesca; Gambardella, Chiara; Di Fino, Alessio; Pittore, Massimiliano; Faimali, Marco

2010-03-01

In this study, we investigated the possibility to improve a new behavioural bioassay (Swimming Speed Alteration test-SSA test) using larvae of marine cyst-forming organisms: e.g. the brine shrimp Artemia sp. and the rotifer Brachionus plicatilis. Swimming speed was investigated as a behavioural end-point for application in ecotoxicology studies. A first experiment to analyse the linear swimming speed of the two organisms was performed to verify the applicability of the video-camera tracking system, here referred to as Swimming Behavioural Recorder (SBR). A second experiment was performed, exposing organisms to different toxic compounds (zinc pyrithione, Macrotrol MT-200, and Eserine). Swimming speed alteration was analyzed together with mortality. The results of the first experiment indicate that SBR is a suitable tool to detect linear swimming speed of the two organisms, since the values have been obtained in accordance with other studies using the same organisms (3.05 mm s(-1) for Artemia sp. and 0.62 mm s(-1) for B. plicatilis). Toxicity test results clearly indicate that swimming speed of Artemia sp. and B. plicatilis is a valid behavioural end-point to detect stress at sub-lethal toxic substance concentrations. Indeed, alterations in swimming speed have been detected at toxic compound concentrations as low as less then 0.1-5% of their LC(50) values. In conclusion, the SSA test with B. plicatilis and Artemia sp. can be a good behavioural integrated output for application in marine ecotoxicology and environmental monitoring programs.

Omega-3 fatty acid deficient male rats exhibit abnormal behavioral activation in the forced swim test following chronic fluoxetine treatment: association with altered 5-HT1A and alpha2A adrenergic receptor expression.

PubMed

Able, Jessica A; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; McNamara, Robert K

2014-03-01

Omega-3 fatty acid deficiency during development leads to enduing alterations in central monoamine neurotransmission in rat brain. Here we investigated the effects of omega-3 fatty acid deficiency on behavioral and neurochemical responses to chronic fluoxetine (FLX) treatment. Male rats were fed diets with (CON, n = 34) or without (DEF, n = 30) the omega-3 fatty acid precursor alpha-linolenic acid (ALA) during peri-adolescent development (P21-P90). A subset of CON (n = 14) and DEF (n = 12) rats were administered FLX (10 mg/kg/d) through their drinking water for 30 d beginning on P60. The forced swimming test (FST) was initiated on P90, and regional brain mRNA markers of serotonin and noradrenaline neurotransmission were determined. Dietary ALA depletion led to significant reductions in frontal cortex docosahexaenoic acid (DHA, 22:6n-3) composition in DEF (-26%, p = 0.0001) and DEF + FLX (-32%, p = 0.0001) rats. Plasma FLX and norfluoxetine concentrations did not different between FLX-treated DEF and CON rats. During the 15-min FST pretest, DEF + FLX rats exhibited significantly greater climbing behavior compared with CON + FLX rats. During the 5-min test trial, FLX treatment reduced immobility and increased swimming in CON and DEF rats, and only DEF + FLX rats exhibited significant elevations in climbing behavior. DEF + FLX rats exhibited greater midbrain, and lower frontal cortex, 5-HT1A mRNA expression compared with all groups including CON + FLX rats. DEF + FLX rats also exhibited greater midbrain alpha2A adrenergic receptor mRNA expression which was positively correlated with climbing behavior in the FST. These preclinical data demonstrate that low omega-3 fatty acid status leads to abnormal behavioral and neurochemical responses to chronic FLX treatment in male rats. Copyright © 2013 Elsevier Ltd. All rights reserved.

Individual differences in circadian locomotor parameters correlate with anxiety- and depression-like behavior.

PubMed

Anyan, Jeffrey; Verwey, Michael; Amir, Shimon

2017-01-01

Disrupted circadian rhythms are a core feature of mood and anxiety disorders. Circadian rhythms are coordinated by a light-entrainable master clock located in the suprachiasmatic nucleus. Animal models of mood and anxiety disorders often exhibit blunted rhythms in locomotor activity and clock gene expression. Interestingly, the changes in circadian rhythms correlate with mood-related behaviours. Although animal models of depression and anxiety exhibit aberrant circadian rhythms in physiology and behavior, it is possible that the methodology being used to induce the behavioral phenotype (e.g., brain lesions, chronic stress, global gene deletion) affect behavior independently of circadian system. This study investigates the relationship between individual differences in circadian locomotor parameters and mood-related behaviors in healthy rats. The circadian phenotype of male Lewis rats was characterized by analyzing wheel running behavior under standard 12h:12h LD conditions, constant dark, constant light, and rate of re-entrainment to a phase advance. Rats were then tested on a battery of behavioral tests: activity box, restricted feeding, elevated plus maze, forced swim test, and fear conditioning. Under 12h:12h LD conditions, percent of daily activity in the light phase and variability in activity onset were associated with longer latency to immobility in the forced swim test. Variability in onset also correlated positively with anxiety-like behavior in the elevated plus maze. Rate of re-entrainment correlated positively with measures of anxiety in the activity box and elevated plus maze. Lastly, we found that free running period under constant dark was associated with anxiety-like behaviors in the activity box and elevated plus maze. Our results provide a previously uncharacterized relationship between circadian locomotor parameters and mood-related behaviors in healthy rats and provide a basis for future examination into circadian clock functioning and mood.