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Sample records for acth stimulation tests

  1. ACTH stimulation test

    MedlinePlus

    ... Groot LJ, de Kretser DM, et al, eds. Endocrinology: Adult and Pediatric . 7th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 102. Chernecky CC, Berger BJ. ACTH stimulation test - diagnostic. In: ... . 13th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap ...

  2. ACTH stimulation test in the captive cheetah (Acinonyx jubatus).

    PubMed

    Köster, L S; Schoeman, J P; Meltzer, D G A

    2007-09-01

    Serum cortisol response was assessed in 8 captive cheetahs, of varying ages, after the intravenous administration of 500 microg of tetracosactide (Synacthen Depot, Novartis, Kempton Park) while maintained under general anaesthesia. In addition, 8 cheetahs were anaesthetised and given an equal volume of saline in order to establish baseline cortisol concentrations at similar stages of anaesthesia. A significant difference in the median cortisol concentration measured over time was found following ACTH administration in the ACTH group (P < 0.001). There was no difference between the median cortisol concentrations in the ACTH group at time-points 120, 150 and 180 min after ACTH stimulation (P = 0.867). Thus it appears appropriate to collect serum 120 to 180 min after tetracosactide administration to assess maximal stimulation of the adrenal in the cheetah. No statistically significant rise was seen in the anaesthetised control group following the injection of saline (P = 0.238).

  3. Repeatability of the ACTH stimulation test as reflected by salivary cortisol response in healthy horses.

    PubMed

    Scheidegger, M D; Gerber, V; Ramseyer, A; Schüpbach-Regula, G; Bruckmaier, R M; van der Kolk, J H

    2016-10-01

    The aim of this study was to further characterize the ACTH stimulation test as reflected by salivary cortisol response and to measure the short- and long-term repeatability of it in healthy horses as a tool to assess the capacity of the adrenal cortex to secrete cortisol. Nineteen healthy horses were subjected to 3 ACTH stimulation tests. Intervals were 2 wk and 5 mo between the first and second and the second and third tests, respectively. A dose of 1-μg/kg BW synthetic ACTH was injected intravenously. Saliva samples were collected at baseline and at 30, 60, 90, 120, 150, and 180 min after administration for cortisol measurements using a competitive enzyme immunoassay. A repeated measures ANOVA was used to compare values within and among horses. Mean ± SD total increase in cortisol concentrations integrated over the entire sampling period was 34.5 ± 11.0 ng/mL. The highest measured concentration at a single time point was 9.7 ± 2.7 ng/mL and was reached after 122 ± 22 min. For the short- and long-term repeatability, intraclass correlation coefficient was 0.90 and 0.33, respectively. The 3 ACTH stimulation tests results differed significantly among (P < 0.00001) but not within (P = 0.538) individual horses. The Freiberger stallions had a higher salivary cortisol baseline concentration and a lower response to ACTH stimulation as compared with Warmblood mares and geldings. The present study confirmed that the administration of ACTH in healthy horses reliably stimulates the salivary secretion of cortisol and shows that the test is repeatable in the short- and long-term. PMID:27565229

  4. Multidrug-Resistant Tuberculosis and Its Association with Adrenal Insufficiency: Assessment with the Low-Dose ACTH Stimulation Test

    PubMed Central

    Rodríguez-Gutiérrez, René; Rendon, Adrian; Barrera-Sánchez, Maximiliano; Carlos-Reyna, Kevin Erick Gabriel; Álvarez-Villalobos, Neri Alejandro; González-Saldivar, Gloria; González-González, José Gerardo

    2016-01-01

    Background. Multidrug-resistant tuberculosis (MDR-TB) is a major public health care concern that affects the life of millions of people around the world. The association of tuberculosis and adrenal insufficiency is well known; however, it is thought to be less prevalent every time. A spike in TB incidence and a lack of evidence of this association in patients with MDR-TB call for reassessment of an illness (adrenal dysfunction) that if not diagnosed could seriously jeopardize patients' health. Objective. To determine the prevalence of adrenocortical insufficiency in patients with MDR-TB using the low-dose (1 μg) ACTH stimulation test at baseline and at 6–12 months of follow-up after antituberculosis treatment and culture conversion. Methods. A total of 48 men or women, aged ≥18 years (HIV-negative patients diagnosed with pulmonary MDR-TB) were included in this prospective observational study. Blood samples for serum cortisol were taken at baseline and 30 and 60 minutes after 1 μg ACTH stimulation at our tertiary level university hospital before and after antituberculosis treatment. Results. Forty-seven percent of subjects had primary MDR-TB; 43.8% had type 2 diabetes; none were HIV-positive. We found at enrollment 2 cases (4.2%) of adrenal insufficiency taking 500 nmol/L as the standard cutoff point value and 4 cases (8.3%) alternatively, using 550 nmol/L. After antituberculosis intensive phase drug-treatment and a negative mycobacterial culture (10.2 ± 3.6 months) adrenocortical function was restored in all cases. Conclusions. In patients with MDR-TB, using the low-dose ACTH stimulation test, a low prevalence of mild adrenal insufficiency was observed. After antituberculosis treatment adrenal function was restored in all cases. Given the increasing and worrying epidemic of MDR-TB these findings have important clinical implications that may help clinicians and patients make better decisions when deciding to test for adrenocortical dysfunction or

  5. Brain sites mediating corticosteroid feedback inhibition of stimulated ACTH secretion

    SciTech Connect

    Jacobson, L.

    1989-01-01

    There is substantial evidence that the brain mediates stress-induced and circadian increases in ACTH secretion and that corticosteroid concentrations which normalize basal plasma ACTH are insufficient to normalize ACTH responses to circadian or stressful stimuli in adrenalectomized rats. To identify brain sites mediating corticosteroid inhibition of stimulated ACTH secretion, two approaches were used. The first compared brain ({sup 14}C)-2-deoxyglucose uptake in rats with differential ACTH responses to stress. Relative to sham-adrenalectomized (SHAM) rats, adrenalectomized rats replaced with low, constant corticosterone levels via a subcutaneous corticosterone pellet (B-PELLET) exhibited elevated and prolonged ACTH responses to a variety of stimuli. Adrenalectomized rate given a circadian corticosterone rhythm via corticosterone in their drinking water exhibited elevated ACTH levels immediately after stress, but unlike B-PELLET rats, terminated stress induced ACTH secretion normally relative to SHAMS. Therefore, the abnormal ACTH responses to stress in B-PELLET rats were due to the lack of both circadian variations and stress-induced increases in corticosterone. Hypoxia was selected as a standardized stimulus for correlating brain ({sup 14}C)-2-deoxyglucose uptake with ACTH secretion. In intact rats, increases in plasma ACTH and decreases in arterial PO{sub 2} correlated with the severity of hypoxia at arterial PCO{sub 2} below 60 mm Hg. Hypoxia PELLET vs. SHAM rats. However, in preliminary experiments, although hypoxia increased brain 2-deoxyglucose uptake in most brain regions, plasma ACTH correlated poorly with 2-deoxyglucose uptake at 12% and 10% O{sub 2}.

  6. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  7. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  8. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  9. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  10. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  11. Stimulation of corticosterone secretion in vitro by brief ACTH exposure

    SciTech Connect

    Keith, L.D.; Tam, B.; Greer, M.A.

    1986-06-01

    The authors examined the relationship between ACTH concentration and exposure duration on stimulation of corticosterone (B) secretion in vitro using perifused enzymatically dispersed rat adrenocortical cells. A modular perifusion apparatus was used that permitted evaluation of 20-24 cell chambers per experimental session. In expt 1,20-1000 pg/ml concentrations of synthetic ACTH-(1-24) were presented to cells for 1 min. In expt 2, 100 pg ACTH-(1-24) was presented to adrenal cells in five dose-duration regimens ranging from 5 pg/min for 20 min to 100 pg/min for 1 min. Perifusal rate was 1 ml/min in all sessions. B was determined by radioimmunoassay. In expt 1 (constant-duration paradigm), 1-min presentation of ACTH-(1-24) produced log-linear dose-response effects across these concentrations. In expt 2 (constant-mass paradigm), identical masses administered in different dose-duration regimens had different steroidogenic efficacies: low-dose long-duration regimens provoked greater total release than high-dose short-duration regimens. Overall, every dose-duration regimen was associated with stimulation of B secretion. These results indicate that 1) very brief exposure to physiological concentrations of ACTH-(1-24) is a significant stimulus for corticosteroid secretion; 2) variations in the dose-duration regimen over the physiological range modifies both the maximum rate of secretion and the duration of secretion, but not the response latency; and 3) ACTH-(1-24) presentation mass is not the sole determinant of B secretion.

  12. Influence of trifluoperazine on ACTH- or angiotensin-stimulated mineralocorticoid and glucocorticoid secretion in man.

    PubMed

    Zofková, I; Hampl, R

    1987-08-01

    During stimulation of adrenocortical secretion the calcium--calmodulin system is activated to a different extent, depending on the secretagogue substance. In the submitted paper the influence of therapeutic doses of the calmodulin inhibitor, trifluoperazine, on aldosterone and cortisol secretion stimulated by ACTH or by activation of endogenous angiotensin by furosemide was investigated in healthy subjects. Trifluoperazine already in amounts of 6 mg/day administered for one week inhibited the "basal" aldosterone secretion assessed in a vertical position (p less than 0.01) and ACTH stimulated secretion (during the 30th minute p less than 0.05). The basal aldosterone secretion assessed in a horizontal position was not affected by trifluoperazine, similarly as it did not affect the secretory response to endogenous angiotensin activated by furosemide, regardless whether a dose of 6 mg or 12 mg/day was used. ACTH stimulated cortisol blood levels were after trifluoperazine insignificantly but constantly lower throughout the test, while they were not altered by trifluoperazine in the furosemide test. The plasma calcium level was not significantly affected by trifluoperazine. It may be concluded that trifluoperazine alters ACTH stimulated mineralocorticoid secretion, while it does not influence angiotensin stimulated secretion. The revealed differences in adrenocortical response to trifluoperazine in vivo cannot be explained merely by a different sensitivity of the calcium-calmodulin system to stimulation by two different secretagogues, but by interaction of some regulatory mechanisms influenced by trifluoperazine with adrenocortical secretion.

  13. Cortisol secretion after adrenocorticotrophin (ACTH) and Dexamethasone tests in healthy female and male dogs

    PubMed Central

    Pessina, Paula; Fernández-Foren, Andrea; Cueto, Enrique; Delucchi, Luis; Castillo, Victor; Meikle, Ana

    2009-01-01

    Background For the conclusive diagnosis of Cushing's Syndrome, a stimulating ACTH test or a low suppressive Dexamethasone test is used. Reports in other species than the dog indicate that plasma cortisol concentration after ACTH administration is affected by gender. We investigated the effect of gender on the cortisol response to ACTH and Dexamethasone tests in dogs. Methods Seven healthy adult Cocker Spaniels (4 females and 3 males) were assigned to a two by two factorial design: 4 dogs (2 females and 2 males) received IV Dexamethasone 0.01 mg/kg, while the other 3 dogs received an IV saline solution (control group). Two weeks later the treatments were reversed. After one month, ACTH was given IV (250 μg/animal) to 4 dogs (2 female and 2 males) while the rest was treated with saline solution (control group). Cortisol concentrations were determined by a direct solid-phase radioimmunoassay and cholesterol and triglycerides by commercial kits. Results and Discussion No effect of treatment was observed in metabolite concentrations, but females presented higher cholesterol concentrations. ACTH-treated dogs showed an increase in cortisol levels in the first hour after sampling until 3 hours post injection. Cortisol concentrations in Dexamethasone-treated dogs decreased one hour post injection and remained low for 3 hours, thereafter cortisol concentrations increased. The increase in cortisol levels from one to two hours post ACTH injection was significantly higher in females than males. In Dexamethasone-treated males cortisol levels decreased one hour post injection up to 3 hours; in females the decrease was more pronounced and prolonged, up to 5 hours post injection. Conclusion We have demonstrated that cortisol response to ACTH and Dexamethasone treatment in dogs differs according to sex. PMID:19686591

  14. CRH stimulation of corticosteroids production in melanocytes is mediated by ACTH.

    PubMed

    Slominski, Andrzej; Zbytek, Blazej; Szczesniewski, Andrzej; Semak, Igor; Kaminski, Jan; Sweatman, Trevor; Wortsman, Jacobo

    2005-04-01

    The response to systemic stress is organized along the hypothalamic-pituitary-adrenal axis (HPA), whereas the response to a peripheral stress (solar radiation) is mediated by epidermal melanocytes (cells of neural crest origin) responsible for the pigmentary reaction. Melanocytes express proopiomelanocortin (POMC), corticotropin-releasing hormone (CRH), and CRH receptor-1 (CRH-R1) and can produce corticosterone. In the present study, incubation of normal epidermal melanocytes with CRH was found to trigger a functional cascade structured hierarchically and arranged along the same algorithm as in the HPA axis: CRH activation of CRH-R1 stimulated cAMP accumulation and increased POMC gene expression and production of ACTH. CRH and ACTH also enhanced production of cortisol and corticosterone, and cortisol production was also stimulated by progesterone. The chemical identity of the cortisol was confirmed by liquid chromatography-mass spectrometry (LC/MS2) with [corrected] mass spectrometry-mass spectrometry analyses. POMC gene silencing abolished the stimulatory effect of CRH on corticosteroid synthesis, indicating that this is indirect and mediated via production of ACTH. Thus the melanocyte response to CRH is highly organized along the same functional hierarchy as the HPA axis. This pattern demonstrates the fractal nature of the response to stress with similar activation sequence at the single-cell and whole body levels. PMID:15572653

  15. Nucleus accumbens deep-brain stimulation efficacy in ACTH-pretreated rats: alterations in mitochondrial function relate to antidepressant-like effects

    PubMed Central

    Kim, Y; McGee, S; Czeczor, J K; Walker, A J; Kale, R P; Kouzani, A Z; Walder, K; Berk, M; Tye, S J

    2016-01-01

    Mitochondrial dysfunction has a critical role in the pathophysiology of mood disorders and treatment response. To investigate this, we established an animal model exhibiting a state of antidepressant treatment resistance in male Wistar rats using 21 days of adrenocorticotropic hormone (ACTH) administration (100 μg per day). First, the effect of ACTH treatment on the efficacy of imipramine (10 mg kg−1) was investigated alongside its effect on the prefrontal cortex (PFC) mitochondrial function. Second, we examined the mood-regulatory actions of chronic (7 day) high-frequency nucleus accumbens (NAc) deep-brain stimulation (DBS; 130 Hz, 100 μA, 90 μS) and concomitant PFC mitochondrial function. Antidepressant-like responses were assessed in the open field test (OFT) and forced swim test (FST) for both conditions. ACTH pretreatment prevented imipramine-mediated improvement in mobility during the FST (P<0.05). NAc DBS effectively improved FST mobility in ACTH-treated animals (P<0.05). No improvement in mobility was observed for sham control animals (P>0.05). Analyses of PFC mitochondrial function revealed that ACTH-treated animals had decreased capacity for adenosine triphosphate production compared with controls. In contrast, ACTH animals following NAc DBS demonstrated greater mitochondrial function relative to controls. Interestingly, a proportion (30%) of the ACTH-treated animals exhibited heightened locomotor activity in the OFT and exaggerated escape behaviors during the FST, together with general hyperactivity in their home-cage settings. More importantly, the induction of this mania-like phenotype was accompanied by overcompensative increased mitochondrial respiration. Manifestation of a DBS-induced mania-like phenotype in imipramine-resistant animals highlights the potential use of this model in elucidating mechanisms of mood dysregulation. PMID:27327257

  16. Nucleus accumbens deep-brain stimulation efficacy in ACTH-pretreated rats: alterations in mitochondrial function relate to antidepressant-like effects.

    PubMed

    Kim, Y; McGee, S; Czeczor, J K; Walker, A J; Kale, R P; Kouzani, A Z; Walder, K; Berk, M; Tye, S J

    2016-01-01

    Mitochondrial dysfunction has a critical role in the pathophysiology of mood disorders and treatment response. To investigate this, we established an animal model exhibiting a state of antidepressant treatment resistance in male Wistar rats using 21 days of adrenocorticotropic hormone (ACTH) administration (100 μg per day). First, the effect of ACTH treatment on the efficacy of imipramine (10 mg kg(-1)) was investigated alongside its effect on the prefrontal cortex (PFC) mitochondrial function. Second, we examined the mood-regulatory actions of chronic (7 day) high-frequency nucleus accumbens (NAc) deep-brain stimulation (DBS; 130 Hz, 100 μA, 90 μS) and concomitant PFC mitochondrial function. Antidepressant-like responses were assessed in the open field test (OFT) and forced swim test (FST) for both conditions. ACTH pretreatment prevented imipramine-mediated improvement in mobility during the FST (P<0.05). NAc DBS effectively improved FST mobility in ACTH-treated animals (P<0.05). No improvement in mobility was observed for sham control animals (P>0.05). Analyses of PFC mitochondrial function revealed that ACTH-treated animals had decreased capacity for adenosine triphosphate production compared with controls. In contrast, ACTH animals following NAc DBS demonstrated greater mitochondrial function relative to controls. Interestingly, a proportion (30%) of the ACTH-treated animals exhibited heightened locomotor activity in the OFT and exaggerated escape behaviors during the FST, together with general hyperactivity in their home-cage settings. More importantly, the induction of this mania-like phenotype was accompanied by overcompensative increased mitochondrial respiration. Manifestation of a DBS-induced mania-like phenotype in imipramine-resistant animals highlights the potential use of this model in elucidating mechanisms of mood dysregulation. PMID:27327257

  17. Endocrine responses of healthy parrots to ACTH and thyroid stimulating hormone.

    PubMed

    Zenoble, R D; Kemppainen, R J; Young, D W; Clubb, S L

    1985-12-01

    Effects of exogenous ACTH on plasma corticosterone and cortisol concentrations and the effects of thyroid stimulating hormone (TSH) on plasma triiodothyronine (T3) and thyroxine (T4) were determined in the following 3 species of parrots: red-lored Amazon (group 1), blue-fronted Amazon (group 2), and African gray (group 3). Each bird was given ACTH (0.125 mg/bird) IM, except for 3 to 4 birds in each group, which were given saline solution (controls). Blood samples were collected before and 90 minutes after ACTH stimulation. In group 1 (n = 12), mean plasma corticosterone concentrations increased significantly (P less than 0.001) from 1.06 microgram/dl (before ACTH) to 4.89 micrograms/dl (after ACTH); mean corticosterone concentrations increased in the control birds from 1.06 microgram/dl to 1.84 microgram/dl; and mean cortisol concentrations increased only slightly from 0.228 microgram/dl to 0.266 microgram/dl. In group 2 (n = 12), mean corticosterone concentrations increased significantly (P less than 0.001) from 2.09 micrograms/dl to 10.58 micrograms/dl; control mean corticosterone concentrations decreased slightly from 2.09 micrograms/dl to 1.77 microgram/dl; and mean cortisol concentrations increased from less than or equal to 0.16 microgram/dl to 0.266 microgram/dl. In group 3 (n = 12), mean plasma corticosterone concentrations increased significantly (P less than or equal to 0.001) from 2.33 micrograms/dl to 4.67 micrograms/dl; mean control plasma corticosterone concentrations decreased from 2.33 micrograms/dl to 1.68 microgram/dl; and plasma corticol concentrations were not detectable. Each bird was given TSH, IM (1 U/bird). Blood samples were collected before and 6 hours after TSH administration. Saline solution was not administered as controls.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Curcumin inhibits ACTH- and angiotensin II-stimulated cortisol secretion and Ca(v)3.2 current.

    PubMed

    Enyeart, Judith A; Liu, Haiyan; Enyeart, John J

    2009-08-01

    Adrenocorticotropic hormone and angiotensin II stimulate cortisol secretion from bovine adrenal zona fasciculata cells by the activation of adenylate cyclase and phospholipase C-coupled receptors. Curcumin (1- 20 muM), a compound found in the spice turmeric, inhibited cortisol secretion stimulated by ACTH, AngII, and 8CPT-cAMP. Curcumin also suppressed ACTH-stimulated increases in mRNAs coding for steroid acute regulatory protein and CYP11a1 steroid hydroxylase. In whole cell patch clamp recordings from AZF cells, curcumin at slightly higher concentrations also inhibited Ca(v)3.2 current. These results identify curcumin as an effective inhibitor of ACTH- and AngII-stimulated cortisol secretion. The inhibition of Ca(v)3.2 current by curcumin may contribute to its suppression of secretion.

  19. CXCL10/CXCR3 signaling mediates inhibitory action by interferon-gamma on CRF-stimulated adrenocorticotropic hormone (ACTH) release.

    PubMed

    Horiguchi, Kotaro; Fujiwara, Ken; Tsukada, Takehiro; Yoshida, Saishu; Higuchi, Masashi; Tateno, Kozue; Hasegawa, Rumi; Takigami, Shu; Ohsako, Shunji; Yashiro, Takashi; Kato, Takako; Kato, Yukio

    2016-05-01

    Secretion of hormones by the anterior pituitary gland can be stimulated or inhibited by paracrine factors that are produced during inflammatory reactions. The inflammation cytokine interferon-gamma (IFN-γ) is known to inhibit corticotropin-releasing factor (CRF)-stimulated adrenocorticotropin (ACTH) release but its signaling mechanism is not yet known. Using rat anterior pituitary, we previously demonstrated that the CXC chemokine ligand 10 (CXCL10), known as interferon-γ (IFN-γ) inducible protein 10 kDa, is expressed in dendritic cell-like S100β protein-positive (DC-like S100β-positive) cells and that its receptor CXCR3 is expressed in ACTH-producing cells. DC-like S100β-positive cells are a subpopulation of folliculo-stellate cells in the anterior pituitary. In the present study, we examine whether CXCL10/CXCR3 signaling between DC-like S100β-positive cells and ACTH-producing cells mediates inhibition of CRF-activated ACTH-release by IFN-γ, using a CXCR3 antagonist in the primary pituitary cell culture. We found that IFN-γ up-regulated Cxcl10 expression via JAK/STAT signaling and proopiomelanocortin (Pomc) expression, while we reconfirmed that IFN-γ inhibits CRF-stimulated ACTH-release. Next, we used a CXCR3 agonist in primary culture to analyze whether CXCL10 induces Pomc-expression and ACTH-release using a CXCR3 agonist in the primary culture. The CXCR3 agonist significantly stimulated Pomc-expression and inhibited CRF-induced ACTH-release, while ACTH-release in the absence of CRF did not change. Thus, the present study leads us to an assumption that CXCL10/CXCR3 signaling mediates inhibition of the CRF-stimulated ACTH-release by IFN-γ. Our findings bring us to an assumption that CXCL10 from DC-like S100β-positive cells acts as a local modulator of ACTH-release during inflammation.

  20. Adrenocortical response to low-dose ACTH test in female patients with rheumatoid arthritis.

    PubMed

    Radikova, Zofia; Rovensky, Jozef; Vlcek, Miroslav; Penesova, Adela; Kerlik, Jana; Vigas, Milan; Imrich, Richard

    2008-12-01

    Alterations in adrenal steroid production have been suggested in females with rheumatoid arthritis (RA). The aim of the present study was to assess adrenocortical function in RA females. We examined 11 female RA patients (RA: age 30 +/- 2 years, BMI 21.0 +/- 0.7 kg/m(2)) and 10 matched healthy controls (C: age 31 +/- 1 years, BMI 21.6 +/- 0.6 kg/m(2)). Low-dose adrenocorticotropic hormone (ACTH) test (i.v. bolus of 1 microg synthetic ACTH) was performed at 10.00 h with blood sampling every 15 min for 90 min. Cortisol, 17-OH-progesterone (17OHP), androstenedione (ASD), and dehydroepiandrosterone (DHEA) were assayed in plasma. Baseline cortisol levels were higher in RA patients (RA: 385 +/- 38 versus C: 229 +/- 28 nmol/L, P= 0.007). In both study groups, ACTH administration increased all the four steroids measured (P < 0.001). Cortisol response to ACTH administration was diminished in RA patients when compared to controls (Delta(max): 284 +/- 24 in RA versus 424 +/- 31 nmol/L in C, P= 0.002). ACTH-induced maximal rise in plasma DHEA was significantly lower in RA patients when compared to controls (Delta(max): 2.59 +/- 0.68 in RA versus 5.57 +/- 1.25 ng/mL in C, P= 0.015). No significant between-groups differences were found in responses of ASD or 17OHP. The molar ratio of ASD:cortisol was significantly lower (P < 0.05) in RA patients at base line, but did not differ during ACTH test. After ACTH bolus, the cortisol:17OHP ratio decreased significantly in the RA group (P < 0.001), whereas there was no change in the control group. The present results show decreased secretion of cortisol and DHEA in RA patients in response to ACTH, suggesting a subtle HPA hypofunction at the adrenocortical level. PMID:19120158

  1. Investigation of the hypothalamo-pituitary-adrenal axis (HPA) by 1 microg ACTH test and metyrapone test in patients with primary fibromyalgia syndrome.

    PubMed

    Calis, M; Gökçe, C; Ates, F; Ulker, S; Izgi, H B; Demir, H; Kirnap, M; Sofuoglu, S; Durak, A C; Tutus, A; Kelestimur, F

    2004-01-01

    Primary fibromyalgia syndrome (PFS) is characterized by widespread chronic pain that affects the musculoskeletal system, fatigue, anxiety, sleep disturbance, headache and postural hypotension. The pathophysiology of PFS is unknown. The hypothalamic-pituitary-adrenal (HPA) axis seems to play an important role in PFS. Both hyperactivity and hypoactivity of the HPA axis have been reported in patients with PFS. In this study we assessed the HPA axis by 1 microg ACTH stimulation test and metyrapone test in 22 patients with PFS and in 15 age-, sex-, and body mass index (BMI)- matched controls. Metyrapone (30 mg/kg) was administered orally at 23:00 h and blood was sampled at 08:30 h the following morning for 11-deoxycortisol. ACTH stimulation test was carried out by using 1 microg (iv) ACTH as a bolus injection after an overnight fast, and blood samples were drawn at 0, 30 and 60 min. Peak cortisol level (659.4 +/- 207.2 nmol/l) was lower in the patients with PFS than peak cortisol level (838.7 +/- 129.6 nmol/l) in the control subjects (p < 0.05). Ten patients (45%) with PFS had peak cortisol responses to 1 microg ACTH test lower than the lowest peak cortisol detected in healthy controls. After metyrapone test 11-deoxycortisol level was 123.7 +/- 26 nmol/l in patients with PFS and 184.2 +/- 17.3 nmol/l in the controls (p < 0.05). Ninety five percent of the patients with PFS had lower 11-deoxycortisol level after metyrapone than the lowest 11-deoxycortisol level after metyrapone detected in healthy controls. We also compared the adrenal size of the patients with that of the healthy subjects and we found that the adrenal size between the groups was similar. This study clearly shows that HPA axis is underactivated in PFS, rather than overactivated. PMID:15053242

  2. Morphological changes in the small intestine of the fetal pig after prenatal stimulation of the sow with ACTH.

    PubMed

    Connell, B J; Bate, L A; Ireland, W; Acorn, R

    1995-04-01

    Twelve pregnant primiparous sows were catheterized on day 102 of gestation and randomly allocated to receive ACTH (days 112-113 of gestation [2d], days 105-parturition [10d]) or saline. At parturition the 3rd, 4th, 6th and 7th piglet born alive were sacrificed either at birth or at 6 h. The later group was fed bovine colostrum through a stomach tube at 30 min, 2 and 4 h of life. Following sacrifice, the small intestine of each piglet was excised, extended and measured. Piglets from sows in the 2d group tended to be heavier with longer small intestines than either the control or 10d groups. When the small intestine length was expressed as a function of body weight, the 10d group had the greatest ratio, suggesting that the pre-parturition maintenance of elevated cortisol levels either enhanced small intestine growth or attenuated overall weight gain. Two types of enterocyte granules were described at the level of the electron microscope: granular and opaque. Opaque granules from piglets born to sows in the 2d treatment group had both a lower volume fraction and were fewer per unit area when compared to those of either the saline or 10d treatments. The process of macromolecule uptake from the intestinal lumen appeared to have been interfered with as a result of an acute prenatal stimulation with ACTH. The above results suggest that in piglets, the level of circulating cortisol differentially controls the processes of IgG absorption, enterocyte replacement and small intestine growth through separate mechanisms. Further, these processes can be manipulated in the prenatal piglet.

  3. Effects of withholding feed on thyrotropin-releasing hormone stimulation test results and effects of combined testing on oral sugar test and thyrotropin-releasing hormone stimulation test results in horses.

    PubMed

    Restifo, Melissa M; Frank, Nicholas; Hermida, Pilar; Sanchez-Londoño, Alfredo

    2016-07-01

    OBJECTIVE To assess effects of withholding feed on thyrotropin-releasing hormone (TRH) stimulation test results used in diagnosis of pituitary pars intermedia dysfunction in horses and determine effects of combined testing on results of the TRH stimulation test and the oral sugar test (OST) used in diagnosis of equine metabolic syndrome. ANIMALS 30 adult horses. PROCEDURES All horses underwent TRH stimulation tests under fed and nonfed conditions, an OST alone, and an OST combined with TRH stimulation testing. For TRH stimulation tests, plasma ACTH concentrations were measured before (baseline) and 10 minutes after (poststimulation) IV TRH administration. For the OST, plasma glucose and insulin concentrations were measured before (baseline) and 60 and 90 minutes after oral corn syrup administration. For combined testing, the TRH stimulation test was initiated immediately after 60-minute posttreatment sample collection for the OST. Results were compared among methods by Wilcoxon matched-pairs, signed rank tests, paired t tests, and Bland-Altman analysis. RESULTS Feeding conditions did not affect median ACTH concentrations when TRH stimulation tests were performed alone. Median baseline ACTH concentration did not differ between TRH stimulation tests performed alone (under fed or nonfed conditions) and those combined with OSTs. Median poststimulation ACTH concentration was significantly lower for combined tests than for solitary TRH stimulation tests. Mean 60-minute plasma glucose concentration was significantly lower for solitary OSTs than for combined tests, but this difference could not be attributed to TRH administration. CONCLUSIONS AND CLINICAL RELEVANCE Combined testing in the manner described impacted ACTH concentrations during TRH stimulation tests and is not recommended at this time. PMID:27347827

  4. ACTH Antagonists.

    PubMed

    Clark, Adrian John; Forfar, Rachel; Hussain, Mashal; Jerman, Jeff; McIver, Ed; Taylor, Debra; Chan, Li

    2016-01-01

    Adrenocorticotropin (ACTH) acts via a highly selective receptor that is a member of the melanocortin receptor subfamily of type 1 G protein-coupled receptors. The ACTH receptor, also known as the melanocortin 2 receptor (MC2R), is unusual in that it is absolutely dependent on a small accessory protein, melanocortin receptor accessory protein (MRAP) for cell surface expression and function. ACTH is the only known naturally occurring agonist for this receptor. This lack of redundancy and high degree of ligand specificity suggests that antagonism of this receptor could provide a useful therapeutic aid and a potential investigational tool. Clinical situations in which this could be useful include (1) Cushing's disease and ectopic ACTH syndrome - especially while preparing for definitive treatment of a causative tumor, or in refractory cases, or (2) congenital adrenal hyperplasia - as an adjunct to glucocorticoid replacement. A case for antagonism in other clinical situations in which there is ACTH excess can also be made. In this article, we will explore the scientific and clinical case for an ACTH antagonist, and will review the evidence for existing and recently described peptides and modified peptides in this role. PMID:27547198

  5. ACTH Antagonists

    PubMed Central

    Clark, Adrian John; Forfar, Rachel; Hussain, Mashal; Jerman, Jeff; McIver, Ed; Taylor, Debra; Chan, Li

    2016-01-01

    Adrenocorticotropin (ACTH) acts via a highly selective receptor that is a member of the melanocortin receptor subfamily of type 1 G protein-coupled receptors. The ACTH receptor, also known as the melanocortin 2 receptor (MC2R), is unusual in that it is absolutely dependent on a small accessory protein, melanocortin receptor accessory protein (MRAP) for cell surface expression and function. ACTH is the only known naturally occurring agonist for this receptor. This lack of redundancy and high degree of ligand specificity suggests that antagonism of this receptor could provide a useful therapeutic aid and a potential investigational tool. Clinical situations in which this could be useful include (1) Cushing’s disease and ectopic ACTH syndrome – especially while preparing for definitive treatment of a causative tumor, or in refractory cases, or (2) congenital adrenal hyperplasia – as an adjunct to glucocorticoid replacement. A case for antagonism in other clinical situations in which there is ACTH excess can also be made. In this article, we will explore the scientific and clinical case for an ACTH antagonist, and will review the evidence for existing and recently described peptides and modified peptides in this role. PMID:27547198

  6. Ovarian localization of 11β-hydroxysteroid dehydrogenase (11βHSD): effects of ACTH stimulation and its relationship with bovine cystic ovarian disease.

    PubMed

    Amweg, A N; Salvetti, N R; Stangaferro, M L; Paredes, A H; Lara, H H; Rodríguez, F M; Ortega, H H

    2013-10-01

    Cystic ovarian disease (COD) is an important cause of infertility in cattle, and ACTH has been involved in regulatory mechanisms related to ovarian function associated with ovulation, steroidogenesis, and luteal function. Here, we examined the localization of 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1) and 11βHSD2 proteins in the ovary of healthy cows and animals with spontaneous and ACTH-induced COD and the in vitro response of the follicular wall exposed to ACTH. After stimulation by ACTH, we documented changes in 11βHSD expression and cortisol secretion by the follicular wall of large antral and follicular cysts. Follicular cysts showed a higher constitutive expression of both enzymes, whereas ACTH induced an increase in 11βHSD1 in tertiary follicles and follicular cysts and a decrease in 11βHSD2 in follicular cysts. Moderate expression of 11βHSD1 was observed by immunohistochemistry in granulosa of control animals, with an increase (P < 0.05) from primary to secondary, tertiary, and atretic follicles. The level of immunostaining in theca interna was lower than that in granulosa. The expression of 11βHSD2 was lower in the granulosa of primary follicles than in that of secondary, tertiary, and atretic follicles and was lower in the theca interna than in the granulosa. In ACTH-induced and spontaneously occurring follicular cysts, differences from controls were observed only in the expression of 11βHSD1 in the granulosa, being higher (P < 0.05) than in tertiary follicles. These findings indicate that follicular cysts may be exposed to high local concentrations of active glucocorticoids and indicate a local role for cortisol in COD pathogenesis and in regulatory mechanisms of ovarian function.

  7. Effects of pramipexole on the duration of immobility during the forced swim test in normal and ACTH-treated rats.

    PubMed

    Kitagawa, Kouhei; Kitamura, Yoshihisa; Miyazaki, Toshiaki; Miyaoka, Junya; Kawasaki, Hiromu; Asanuma, Masato; Sendo, Toshiaki; Gomita, Yutaka

    2009-07-01

    The dopamine D2/D3 receptor agonist pramipexole has clinically been proven to improve depression or treatment-resistant depression. However, the involvement of the dopamine receptor system on the effect of pramipexole on depression remains unclear. We examined the influence of pramipexole on the duration of immobility during the forced swim test in normal and adrenocorticotropic hormone (ACTH)-treated rats and further analyzed the possible role of dopamine receptors in this effect. Additionally, the mechanism by which pramipexole acts in this model was explored specifically in relation to the site of action through the use of microinjections into the intramedial prefrontal cortex and nucleus accumbens. Pramipexole (0.3-1 mg/kg) significantly decreased the duration of immobility in normal and ACTH-treated rats. This effect was blocked by L-741,626, a D2 receptor antagonist, and nafadotride, a D3 receptor antagonist, in normal rats. Furthermore, infusions of pramipexole into the intranucleus accumbens, but not the medial prefrontal cortex, decreased the immobility of normal and ACTH-treated rats during the forced swim test. Taken together, the results of these experiments suggested that pramipexole, administered into the intranucleus accumbens rather than the medial prefrontal cortex, exerted an antidepressant-like effect on ACTH-treated rats via the dopaminergic system. The immobility-decreasing effect of pramipexole may be mediated by dopamine D2 and D3 receptors.

  8. Effects of (+)-8-OH-DPAT on the duration of immobility during the forced swim test and hippocampal cell proliferation in ACTH-treated rats.

    PubMed

    Miyake, Ayaka; Kitamura, Yoshihisa; Miyazaki, Ikuko; Asanuma, Masato; Sendo, Toshiaki

    2014-07-01

    In the present study, we examined the effect of ACTH on the immobilization of rats in the forced swim test and hippocampal cell proliferation after administration of the 5-HT1A receptor agonist, R-(+)-8-hydroxy-2-di-n-propylamino tetralin ((+)-8-OH-DPAT). Chronic treatment with (+)-8-OH-DPAT (0.01-0.1 mg/kg, s.c.) significantly decreased the duration of immobility in saline- and ACTH-treated rats. Chronic administration of ACTH caused a significant decrease in hippocampal cell proliferation. However, (+)-8-OH-DPAT significantly normalized cell proliferation in ACTH-treated rats. We then investigated the effects of (+)-8-OH-DPAT on the expression of brain-derived neurotrophic factor (BDNF) and cyclin D1 (elements of cyclic adenosine monophosphate response element-binding protein (CREB)-BDNF and Wnt signaling pathways, respectively) in the hippocampus of saline- and ACTH-treated rats. ACTH treatment significantly decreased the expression of cyclin D1, while treatment with (+)-8-OH-DPAT normalized the expression of cyclin D1 in ACTH-treated rats. However, the expression of BDNF did not change in either saline- or ACTH-treated rats. These findings suggest that the antidepressant effects of (+)-8-OH-DPAT in treatment-resistant animals may be attributed to an enhancement of hippocampal cell proliferation, at least in part due to an enhancement of cyclin D1 expression.

  9. Parallel stimulation of ACTH, beta-LPH + beta-endorphin and alpha-MSH release by alpha-adrenergic agents in rat anterior pituitary cells in culture.

    PubMed

    Raymond, V; Lépine, J; Giguère, V; Lissitzky, J C; Côté, J; Labrie, F

    1981-06-01

    Characteristics of the alpha-adrenergic stimulation of ACTH, beta-endorphin + beta-LPH and alpha-MSH release were studied in rat anterior pituitary cells in primary culture. Parallel changes of ACTH, beta-endorphin + beta-LPH and alpha-MSh release were found under all stimulatory and inhibitory conditions by natural and synthetic catecholamine agonists and antagonists. (-)Epinephrine and (-)norepinephrine lead to a 8--10-fold stimulation of peptide release at ED50 values of 20 and 90 nM, respectively. The stereoselectivity of the alpha-adrenergic stimulatory action on peptide release is indicated by a 100-fold higher activity of (-)- than (+)norepinephrine while (-)epinephrine is 10 times more potent than the corresponding (+) stereoisomer. The involvement of a typical alpha-adrenergic mechanism in the control of release of ACTH, beta-endorphin and related peptides in rat anterior pituitary gland is indicated by the following order of potency of a series of catecholaminergic agents (ED50 values): (-)epinephrine (20 nM) greater than (-)norepinephrine (90 nm) greater than phenylephrine (400 nM) greater than isoproterenol (6000 nM). The stimulatory effect of (-)epinephrine or phenylephrine is completely reversed by low concentrations of the alpha-adrenergic antagonist phentolamine while the beta-adrenergic antagonist propranolol has no effect up to 10 muM. Beside providing an easily accessible pure population of post-synaptic alpha-adrenergic receptors having potential applications as a model for other less accessible alpha-adrenergic brain systems, the present data suggest the possibility of the direct involvement of a catecholamine in the physiological control of ACTH secretion in the rat anterior pituitary gland.

  10. Comparative analysis of plasma 17-hydroxyprogesterone and cortisol responses to ACTH in patients with various adrenal tumors before and after unilateral adrenalectomy.

    PubMed

    Tóth, M; Rácz, K; Adleff, V; Varga, I; Fütö, L; Jakab, C; Karlinger, K; Kiss, R; Gláz, E

    2000-05-01

    Patients with non-hyperfunctioning adrenal adenomas often have an increased plasma 17-hydroxyprogesterone response to ACTH stimulation. The effects of adrenal surgery on this abnormality have rarely been investigated. One hundred and sixty-one patients with unilateral adrenal tumors (non-hyperfunctioning adenomas, 78; cortisol-producing adenomas, 8; aldosterone-producing adenomas, 37; adrenal cysts, 12; pheochromocytomas, 26) were studied. Patients before and after adrenal surgery as well as 60 healthy subjects underwent an ACTH stimulation test using 2 mg synthetic ACTH(1-24) (Cortrosyn Depot, Organon). Basal and ACTH-stimulated plasma 17-hydroxyprogesterone and cortisol concentrations are reported. Before adrenal surgery, the basal plasma 17-hydroxyprogesterone concentrations were normal in patients with all types of tumors. However, the ACTH-stimulated plasma 17-hydroxyprogesterone levels were abnormally increased in 53% and 31% of patients with non-hyperfunctioning adenomas and aldosterone-producing adenomas, respectively. In addition, a few patients with adrenal cysts and pheochromocytomas also showed an increased ACTH-stimulated 17-hydroxyprogesterone response. After unilateral adrenalectomy, this hormonal abnormality disappeared in most, although not all patients with adrenal tumors. In patients with non-hyperfunctioning adrenal tumors, ACTH-stimulated plasma 17-hydroxyprogesterone and cortisol concentrations significantly correlated with the size of the tumors. These results firmly indicate that the tumoral mass itself may be responsible for the increased plasma 17-hydroxyprogesterone and cortisol responses after ACTH stimulation in patients with non-hyperfunctioning and hyperfunctioning adrenal adenomas. PMID:10882146

  11. CORTICOTROPINS (ACTH)

    PubMed Central

    Li, Choh Hao; Fønss-Bech, Peter; Geschwind, Irving I.; Hayashida, Tetsuo; Hungerford, Gerald F.; Lostroh, Ardis J.; Lyons, William R.; Moon, Henry D.; Reinhardt, William O.; Sideman, Martin

    1957-01-01

    Purified α-corticotropin has been reported to exercise the following biological effects: (a) stimulation of the adrenal glands in normal and hypophysectomized rats, (b) production of blood eosinopenia in hypophysectomized rats, (c) maintenance of muscle glycogen in hypophysectomized rats, (d) inhibition of growth-promoting activity of somatotropin, (e) stimulation of melanocytes in the skin of frogs, (f) mobilization of fat into the liver of fasted mice, (g) stimulation of the accessory sex glands of castrated-hypophysectomized male rats, (h) induction of deciduoma formation in hypophysectomized-oophorectomized rats, and (i) elevation of the total red cell volume in hypophysectomized rats. α-Corticotropin has also been shown for the first time to act in synergism with lactogenic hormone as an essential galactopoietic hormone. The ability of α-corticotropin to elicit biological responses in the absence of the adrenal cortex is discussed. PMID:13416472

  12. [Effects of transcutaneous nerve stimulation on the plasma and CSF concentrations of beta-endorphin and the plasma concentrations of ACTH, cortisol and prolactin in hysterectomized women with postoperative pain].

    PubMed

    Rodríguez, E; Meizoso, M J; Garabal, M; Fernández, M P; Rodríguez-Buján, L; Belmonte, A

    1992-01-01

    Plasmatic and cerebrospinal fluid levels of beta-endorphin and plasmatic concentration of ACTH, cortisol, and prolactin were investigated in 10 healthy volunteers free of pain and in a group of 38 patients who presented moderate or intense postoperative pain. The analgesic technique was transcutaneous neural stimulation. In 28 patients the stimulation was delivered at 40-80 Hz (high frequency) whereas in the remaining 10 patients it was administered in a placebo form. Measurements of hormone concentrations were performed using radioimmunoassay techniques. In patients free of pain hormone analysis was done at once, whereas in patients with pain this analysis was performed before and one hour after transcutaneous neural stimulation. We compared data obtained in control subjects with data collected in patients before and one hour after high frequency and placebo transcutaneous neural stimulation. Levels of beta-endorphin were comparable in patients with and without pain. However, ACTH, cortisol, and prolactin were increased in patients with pain. High frequency stimulation induced greater beta-endorphin levels than placebo neural stimulation and slightly lower concentration of prolactin. There were no significant differences in ACTH and cortisol levels.

  13. Effects of bupropion on the forced swim test and release of dopamine in the nucleus accumbens in ACTH-treated rats.

    PubMed

    Kitamura, Yoshihisa; Yagi, Takahiko; Kitagawa, Kouhei; Shinomiya, Kazuaki; Kawasaki, Hiromu; Asanuma, Masato; Gomita, Yutaka

    2010-08-01

    The dopamine reuptake inhibitor bupropion has clinically been proven to improve depression and treatment-resistant depression. We examined its influence on the duration of immobility during the forced swim test in adrenocorticotropic hormone (ACTH)-treated rats and further analyzed the possible role of dopamine receptors in this effect. Additionally, the mechanism by which bupropion acts in this model was explored specifically in relation to the site of action through the use of microinjections into the medial prefrontal cortex and nucleus accumbens. Bupropion significantly decreased the duration of immobility in normal and ACTH-treated rats. This effect was blocked by D2 and D3 receptor antagonists in normal rats. Furthermore, infusions of bupropion into the nucleus accumbens, but not medial prefrontal cortex, decreased the immobility of normal and ACTH-treated rats during the forced swim test. Bupropion treatment plus repeated ACTH treatment significantly increased the extracellular dopamine concentration. These findings suggest the antidepressant-like effect of bupropion to be related to levels of dopamine in the rat nucleus accumbens.

  14. Effects of smoking on ACTH and cortisol secretion

    SciTech Connect

    Seyler, L.E. Jr.; Fertig, J.; Pomerleau, O.; Hunt, D.; Parker, K.

    1984-01-02

    The relationships among changes in plasma nicotine, ACTH, and cortisol secretion after smoking were investigated. Ten male subjects smoked cigarettes containing 2.87 mg nicotine and 0.48 mg nicotine. No rises in cortisol or ACTH were detected after smoking 0.48 mg nicotine cigarettes. Cortisol rises were significant in 11 of 15 instances after smoking 2.87 mg nicotine cigarattes, but ACTH rose significantly in only 5 of the 11 instances where cortisol increased. Each ACTH rise occurred in a subject who reported nausea and was observed to be pale, sweaty, and tachycardic. Peak plasma nicotine concentrations were not significantly different in sessions when cortisol rose with or without ACTH increases, but cortisol increases were significantly greater in nauseated than in non-nauseated smokers. This data suggest that smoking-induced nausea stimulates cortisol release by stimulating ACTH secretion and that cortisol secretion in non-nauseated smokers may occur through a non-ACTH mechanism.

  15. Growth hormone stimulation test

    MedlinePlus

    Arginine test; Arginine-GHRH test ... of re-inserting the needle each time. The test takes between 2 to 5 hours. The procedure ... eat for 10 to 12 hours before the test. Eating food can change the test results. Some ...

  16. Effects of imipramine and bupropion on the duration of immobility of ACTH-treated rats in the forced swim test: involvement of the expression of 5-HT2A receptor mRNA.

    PubMed

    Kitamura, Yoshihisa; Fujitani, Yoshika; Kitagawa, Kouhei; Miyazaki, Toshiaki; Sagara, Hidenori; Kawasaki, Hiromu; Shibata, Kazuhiko; Sendo, Toshiaki; Gomita, Yutaka

    2008-02-01

    We examined the effect of chronic administration of imipramine and bupropion, monoamine reuptake inhibitors, on the duration of immobility in the forced swim test and serotonin (5-HT)(2A) receptor function in the form of 5-HT(2A) receptor mRNA levels in rats chronically treated with adrenocorticotropic hormone (ACTH). The immobility-decreasing effect of bupropion without imipramine did not influence the chronic ACTH treatment. The effect on the expression of 5-HT(2A) receptor mRNA of chronic ACTH treatment was decreased by bupropion, but not imipramine. These results suggest that bupropion has the effect of reducing immobility time in the forced swim test in the tricyclic antidepressant-resistant depressive model induced by chronic ACTH treatment in rats, and that decreased 5-HT(2A) receptor mRNA levels may be involved in this phenomenon.

  17. ACTH (Adrenocorticotropic Hormone) Test

    MedlinePlus

    ... disease , also called primary adrenal insufficiency: decreased cortisol production due to adrenal gland damage Secondary adrenal insufficiency: decreased cortisol production because of pituitary dysfunction Hypopituitarism : pituitary dysfunction or ...

  18. ACTH blood test

    MedlinePlus

    ... early in the morning. This is important, because cortisol level varies throughout the day. You may also ... results. These medicines include glucocorticoids such as prednisone, hydrocortisone, or dexamethasone.

  19. Role of the ACTH test and estimation of a safe dose for high potency steroids in vitiligo: A prospective randomized study

    PubMed Central

    de la Fuente-García, Alberto; Gómez-Flores, Minerva; Mancillas-Adame, Leonardo; Ocampo-Candiani, Jorge; Welsh-Lozano, Oliverio; Pérez, Jesús Zacarías Villarreal; González-González, José Gerardo; Lavalle-González, Fernando

    2014-01-01

    Background: Topical corticosteroids are used as first line of therapy for vitiligo, although side effects such as adrenal insufficiency are possible. Objectives: To establish the role of ACTH test before, during, and after treatment with high potency topical steroids; to determine if adrenal insufficiency occurs secondary to the use of high potency topical steroids in patients with vitiligo and intact cutaneous barrier; and also to determine response to treatment and side effects. Materials and Methods: Forty-four adults with non-segmental vitiligo affecting 20% or less of the body surface area were included and randomized to receive topical clobetasol propionate 0.05% cream (group 1) or placebo (group 2) for 12 weeks, with a maximum dose of 50 g per week. The placebo group was crossed over after week 6 and started on clobetasol until completion of the study. Serum cortisol levels with the 1 μg ACTH test were determined at baseline and on weeks 6 and 12. Results: No adrenal insufficiency was detected nor statistical significance was achieved when comparing cortisol levels between and within the groups at baseline and weeks 6 and 12. Group 1 had a better response to therapy but with more side effects. Conclusions: Doses of 50 g or less per week of clobetasol during a period of 12 weeks are safe on adult vitiligo patients, although local side effects are possible. Repigmentation rates were incomplete with single steroid therapy, making combined therapy a better option. PMID:24860741

  20. Deep Brain Stimulation Tested for Early Alzheimer's

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_160137.html Deep Brain Stimulation Tested for Early Alzheimer's Although treatment seems ... 2016 THURSDAY, July 28, 2016 (HealthDay News) -- Deep brain stimulation appears safe for people with early Alzheimer's ...

  1. Follicle-stimulating hormone (FSH) blood test

    MedlinePlus

    ... the test done on certain days of your menstrual cycle. ... In women, FSH helps manage the menstrual cycle and stimulates the ovaries to produce eggs. The test is used to help diagnose or evaluate: Menopause Women who have polycystic ovary ...

  2. A Novel Medical Treatment of Cushing's Due to Ectopic ACTH in a Patient With Neurofibromatosis Type 1

    PubMed Central

    Bano, Gul; Mir, Farheen; Beharry, Nigel; Wilson, Philip; Hodgson, Shirley; Schey, Stephen

    2012-01-01

    A 64-year-old male presented with neurofibromatosis 1 and Cushing’s syndrome. Clinically he was over weight, depressed with extensive skin bruising and hypertension. His 24 hours urinary metanephrines, urinary 5HIAA, gut peptides and chromgranin levels were normal. His renal function and renal MRI scan was also normal. His cortisol failed to suppress on overnight dexamethsone suppression test. His low dose dexamethasone suppression with CRH stimulation showed failure of suppression of cortisol to < 50 nmol/L and ACTH was measurable at 10 ng/L on day 3. There was no response of ACTH or cortisol to CRH stimulation. His ACTH precursors were high at 126 pmol/L consistent with defective pro-opiomelanocortin (POMC) processing suggesting an ectopic source of ACTH production. The MRI scan of his pituitary and CT scan of the adrenal glands was normal. His octreotide scan was negative. The source of his ectopic ACTH was most likely a large retroperitoneal plexiform neurofibroma seen on CT abdomen that had undergone malignant peripheral nerve sheath tumour transformation on histology. He was a poor surgical risk for tumour debulking procedure. In view of the available literature and role of c-kit signalling in neurofibromatosis, he was treated with Imitinib. Four months after the treatment his Cushings had resolved on biochemical testing. After a year his plexiform neurofibroma has not increased in size. To our knowledge, this is the first case of NF1 associated with clinical and biochemical features of Cushing’s secondary to ectopic ACTH due to MPNST in a plexiform neurofibroma and its resolution on treatment with imatinib. PMID:23853621

  3. A Novel Medical Treatment of Cushing's Due to Ectopic ACTH in a Patient With Neurofibromatosis Type 1.

    PubMed

    Bano, Gul; Mir, Farheen; Beharry, Nigel; Wilson, Philip; Hodgson, Shirley; Schey, Stephen

    2013-01-01

    A 64-year-old male presented with neurofibromatosis 1 and Cushing's syndrome. Clinically he was over weight, depressed with extensive skin bruising and hypertension. His 24 hours urinary metanephrines, urinary 5HIAA, gut peptides and chromgranin levels were normal. His renal function and renal MRI scan was also normal. His cortisol failed to suppress on overnight dexamethsone suppression test. His low dose dexamethasone suppression with CRH stimulation showed failure of suppression of cortisol to < 50 nmol/L and ACTH was measurable at 10 ng/L on day 3. There was no response of ACTH or cortisol to CRH stimulation. His ACTH precursors were high at 126 pmol/L consistent with defective pro-opiomelanocortin (POMC) processing suggesting an ectopic source of ACTH production. The MRI scan of his pituitary and CT scan of the adrenal glands was normal. His octreotide scan was negative. The source of his ectopic ACTH was most likely a large retroperitoneal plexiform neurofibroma seen on CT abdomen that had undergone malignant peripheral nerve sheath tumour transformation on histology. He was a poor surgical risk for tumour debulking procedure. In view of the available literature and role of c-kit signalling in neurofibromatosis, he was treated with Imitinib. Four months after the treatment his Cushings had resolved on biochemical testing. After a year his plexiform neurofibroma has not increased in size. To our knowledge, this is the first case of NF1 associated with clinical and biochemical features of Cushing's secondary to ectopic ACTH due to MPNST in a plexiform neurofibroma and its resolution on treatment with imatinib.

  4. Adrenocorticotropic Hormone Suppresses Gonadotropin-Stimulated Estradiol Release from Zebrafish Ovarian Follicles

    PubMed Central

    Alsop, Derek; Ings, Jennifer S.; Vijayan, Mathilakath M.

    2009-01-01

    While stress is known to impact reproductive performance, the pathways involved are not entirely understood. Corticosteroid effects on the functioning of the hypothalamus-pituitary-gonadal axis are thought to be a key aspect of stress-mediated reproductive dysfunction. A vital component of the stress response is the pituitary secretion of adrenocorticotropic hormone (ACTH), which binds to the melanocortin 2 receptor (MC2R) in the adrenal glands and activates cortisol biosynthesis. We recently reported MC2R mRNA abundance in fish gonads leading to the hypothesis that ACTH may be directly involved in gonadal steroid modulation. Using zebrafish (Danio rerio) ovarian follicles, we tested the hypothesis that acute ACTH stimulation modulates cortisol and estradiol (E2) secretion. ACTH neither affected cortisol nor unstimulated E2 release from ovarian follicles. However, ACTH suppressed human chorionic gonadotropin (hCG)-stimulated E2 secretion in a dose-related manner, with a maximum decrease of 62% observed at 1 I.U. ACTH mL−1. This effect of ACTH on E2 release was not observed in the presence of either 8-bromo-cAMP or forskolin, suggesting that the mechanism(s) involved in steroid attenuation was upstream of adenylyl cyclase activation. Overall, our results suggest that a stress-induced rise in plasma ACTH levels may initiate a rapid down-regulation of acute stimulated E2 biosynthesis in the zebrafish ovary, underscoring a novel physiological role for this pituitary peptide in modulating reproductive activity. PMID:19649243

  5. Causal ACTH-Depot Therapy during Pregnancies following Infertility Treatment.

    PubMed

    Klimek, Rudolf; Klimek, Marek; Gralek, Peter; Jasiczek, Dariusz

    2012-01-01

    The aim of this paper was to confirm the efficacy of adrenocorticotropin depot (ACTH-depot) therapy in pregnancies with threatened miscarriage and preterm delivery through the desired stimulation of the adrenal glands controlled by the rest of organism. The activity of hypothalamic-pituitary-adrenal axis plays a key role in pregnancy. Such naturally stimulated endogenous corticosteroid hormones are free from unwanted side effects of their synthetics analogs. Low level of maternal blood ACTH and insufficient increase of induced by hypothalamic hormones oxytocinases (cystine-β-aminopeptidases) were indication to ACTH-depot therapy (0.5 mg/week) in our consecutive prospective studies. Contrary to antenatal use of synthetic corticosteroids, there are no temporal limits of this therapy, which has to be more often recommended into clinical prevention of fetal morbidity, treatment of premature delivery, and finally elimination of the newborn's mortality caused by the neuroendocrinological gestoses. PMID:22666262

  6. Radioimmunoassay of ACTH in plasma

    PubMed Central

    Berson, Solomon A.; Yalow, Rosalyn S.

    1968-01-01

    Techniques are described in detail for a radioimmunoassay of plasma adrenocorticotropin (ACTH) that is capable of detecting hormone in unextracted normal human plasma at 1:5 dilution under the conditions described. The sensitivity of the assay is at the level of 1 μμg/ml (equivalent to 0.014 mU/100 ml). In normal subjects ACTH concentrations averaged 22 μμg/ml (equivalent to 0.308 mU/100 ml) plasma at 8-10 a.m. In a smaller group the concentrations averaged 9.6 μμg/ml (equivalent to 0.134 mU/100 ml) at 10-11 p.m. Although a circadian rhythm in normal subjects was not always well marked throughout the daytime hours, plasma ACTH usually fell to its lowest value in the late evening. In hospital patients who were not acutely ill, concentrations were infrequently above 100 μμg/ml in the morning and usually fell to significantly lower levels in the late evening. Severely ill hospital patients occasionally exhibited a.m. concentrations above 200 μμg/ml. In a group of subjects showing frequent spiking of plasma 17-OHCS concentrations throughout the day parallel spiking of plasma ACTH as well was generally observed. Metyrapone produced marked increases in plasma ACTH within 24 hr in all cases and generally within 3-6 hr except when started late in the day. Dexamethasone brought about a persistent reduction in plasma ACTH in a patient under continued treatment with metyrapone. Hypoglycemia, electroshock, surgery under general anesthesia, histalog and vasopressin administration were usually followed by significant increases in plasma ACTH concentration. Prior administration of dexamethasone blocked the response to hypoglycemia. Marked elevations in plasma ACTH were observed in patients with adrenal insufficiency off steroid therapy, in Cushing's disease after adrenalectomy even in the presence of persistent hypercortisolemia, and in some untreated patients with Cushing's disease. Umbilical cord blood contained higher plasma ACTH concentrations than maternal blood at

  7. Plasma adrenocorticotropin (ACTH) concentrations and clinical response in horses treated for equine Cushing's disease with cyproheptadine or pergolide.

    PubMed

    Perkins, G A; Lamb, S; Erb, H N; Schanbacher, B; Nydam, D V; Divers, T J

    2002-11-01

    Plasma ACTH levels have been variable in horses with a positive clinical response for therapy for equine Cushing's Disease (ECD). Therefore, our purpose was to determine the value of monitoring plasma adrenocorticotropin (ACTH) levels during treatment of equine Cushing's disease (ECD) with either cyproheptadine (n = 32) or pergolide (n = 10). First, we validated the chemiluminescent ACTH assay (specificity, precision, accuracy, intra-assay and interassay variations) and tested methods of handling the whole blood from the time of collection to when the ACTH was assayed. The sensitivity and specificity of high plasma ACTH levels for detecting ECD was determined in a retrospective study on hospitalised horses (n = 68). Surveys were sent to veterinarians who submitted equine ACTH levels that were high initially and had at least 2 ACTH samples to determine the value of monitoring ACTH levels during therapy of ECD. The ACTH chemiluminescent assay was valid. The ACTH was stable when whole blood was collected and held in plastic tubes for 8 h before separating the plasma. The sensitivity and specificity of plasma ACTH levels for detecting ECD were 84% (n = 19,95% CI 60,97) and 78% (n = 49,95% CI 63,88), respectively. Treated horses generally showed a decrease in plasma ACTH. Plasma ACTH levels may be helpful when monitoring therapy of ECD, although improvement in clinical signs should be considered most important. There were no differences between cyproheptadine and pergolide in terms of improvements in any of the clinical signs.

  8. Anomalous responses to stimulation and suppression tests in Cushing's syndrome due to a calcified adrenal adenoma

    PubMed Central

    Epstein, S.; McLaren, E. H.; Goldin, A. R.

    1973-01-01

    A case of Cushing's syndrome, due to an adrenal adenoma, which responded to dexamethasone with a rise in plasma urinary steroids is described. Further unusual features were radiologically visible calcification and a response to ACTH stimulation. ImagesFig. 1Fig. 2 PMID:4377169

  9. ACTH Regulation of Adrenal SR-B1.

    PubMed

    Shen, Wen-Jun; Azhar, Salman; Kraemer, Fredric B

    2016-01-01

    The adrenal gland is one of the prominent sites for steroid hormone synthesis. Lipoprotein-derived cholesterol esters (CEs) delivered via SR-B1 constitute the dominant source of cholesterol for steroidogenesis, particularly in rodents. Adrenocorticotropic hormone (ACTH) stimulates steroidogenesis through downstream actions on multiple components involved in steroidogenesis. Both acute and chronic ACTH treatments can modulate SR-B1 function, including its transcription, posttranscriptional stability, phosphorylation and dimerization status, as well as the interaction with other protein partners, all of which result in changes in the ability of SR-B1 to mediate HDL-CE uptake and the supply of cholesterol for conversion to steroids. Here, we provide a review of the recent findings on the regulation of adrenal SR-B1 function by ACTH. PMID:27242666

  10. ACTH Regulation of Adrenal SR-B1

    PubMed Central

    Shen, Wen-Jun; Azhar, Salman; Kraemer, Fredric B.

    2016-01-01

    The adrenal gland is one of the prominent sites for steroid hormone synthesis. Lipoprotein-derived cholesterol esters (CEs) delivered via SR-B1 constitute the dominant source of cholesterol for steroidogenesis, particularly in rodents. Adrenocorticotropic hormone (ACTH) stimulates steroidogenesis through downstream actions on multiple components involved in steroidogenesis. Both acute and chronic ACTH treatments can modulate SR-B1 function, including its transcription, posttranscriptional stability, phosphorylation and dimerization status, as well as the interaction with other protein partners, all of which result in changes in the ability of SR-B1 to mediate HDL-CE uptake and the supply of cholesterol for conversion to steroids. Here, we provide a review of the recent findings on the regulation of adrenal SR-B1 function by ACTH. PMID:27242666

  11. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  12. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  13. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  14. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  15. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  16. The significance of ACTH for the process of formation of complex heparin compounds in the blood during immobilization stress

    NASA Technical Reports Server (NTRS)

    Kudryashov, B. A.; Shapiro, F. B.; Lomovskaya, F. B.; Lyapina, L. A.

    1979-01-01

    Adrenocorticotropin (ACTH) was administered to rats at different times following adrenalectomy. Adrenocorticotropin caused a significant increase in the formation of heparin complexes even in the absence of stress factor. When ACTH secretion is blocked, immobilization stress is not accompanied by an increase in the process of complex formation. The effect of ACTH on the formation of heparin complexes was mediated through its stimulation of the adrenal cortex.

  17. Impact of ACTH Signaling on Transcriptional Regulation of Steroidogenic Genes

    PubMed Central

    Ruggiero, Carmen; Lalli, Enzo

    2016-01-01

    The trophic peptide hormone adrenocorticotropic (ACTH) stimulates steroid hormone biosynthesis evoking both a rapid, acute response and a long-term, chronic response, via the activation of cAMP/protein kinase A (PKA) signaling. The acute response is initiated by the mobilization of cholesterol from lipid stores and its delivery to the inner mitochondrial membrane, a process that is mediated by the steroidogenic acute regulatory protein. The chronic response results in the increased coordinated transcription of genes encoding steroidogenic enzymes. ACTH binding to its cognate receptor, melanocortin 2 receptor (MC2R), stimulates adenylyl cyclase, thus inducing cAMP production, PKA activation, and phosphorylation of specific nuclear factors, which bind to target promoters and facilitate coactivator protein recruitment to direct steroidogenic gene transcription. This review provides a general view of the transcriptional control exerted by the ACTH/cAMP system on the expression of genes encoding for steroidogenic enzymes in the adrenal cortex. Special emphasis will be given to the transcription factors required to mediate ACTH-dependent transcription of steroidogenic genes. PMID:27065945

  18. Cushing's syndrome due to ectopic ACTH secretion.

    PubMed

    Cieszyński, Łukasz; Berendt-Obołończyk, Monika; Szulc, Michał; Sworczak, Krzysztof

    2016-01-01

    Cushing's syndrome (CS) is defined as a constellation of clinical signs and symptoms occurring due to hypercortisolism. Cortisol excess may be endogenous or exogenous. The most common cause of CS is glucocorticoid therapy with supraphysiological (higher than in the case of substitution) doses used in various diseases (e.g. autoimmune). One possible CS cause is ectopic (extra-pituitary) ACTH secretion (EAS) by benign or malignant tumours. Since its first description in 1963, EAS aetiology has changed, i.e. as well as small cell lung cancer (SCLC), higher incidence in other malignancies has been reported. Ectopic ACTH secretion symptoms are usually similar to hypercortisolism symptoms due to other causes. A clinical suspicion of CS requires laboratory investigations. There is no single and specific laboratory test for making a CS diagnosis, and therefore multiple dynamic tests should be ordered. A combination of multiple laboratory noninvasive and invasive tests gives 100% sensitivity and 98% specificity for EAS diagnosis. If the EAS is caused by localised malignancy, surgery is the optimal treatment choice. Radical tumour excision may be performed in 40% of patients, and 80% of them are cured of the disease. The authors present an interesting clinical case of EAS, which is always a huge diagnostic challenge for clinicians. (Endokrynol Pol 2016; 67 (4): 458-464). PMID:27387249

  19. Catheterization during adrenal vein sampling for primary aldosteronism: failure to use (1-24) ACTH may increase apparent failure rate.

    PubMed

    Kline, Gregory A; So, Benny; Dias, Valerian C; Harvey, Adrian; Pasieka, Janice L

    2013-07-01

    "Successful" adrenal vein catheterization in primary aldosteronism (PA) is often defined by a ratio of >3:1 of cortisol in the adrenal vein vs the inferior vena cava. Non-use of corticotropin (ACTH) during sampling may increase the apparent failure rate of adrenal vein catheterization due to lower cortisol levels. A retrospective study was performed on all patients with confirmed unilateral PA between June 2005 and August 2011. Adrenal vein sampling (AVS) included simultaneous bilateral baseline samples with repeat sampling 15 minutes after intravenous infusion of 250 μg of Cortrosyn (ACTH-S). Successful catheter placement was judged as adrenal cortisol:IVC cortisol of >3:1, applied to both baseline and ACTH-S samples and lateralization of aldosteronism was judged as normalized aldosterone/cortisol (A/C) ratio >3 times the contralateral A/C ratio. In ACTH-S samples, 94% of right-sided catheterizations were biochemically successful with 100% success on the left. Among baseline samples, only 47% of right- and 44% of left-sided samples met the 3:1 cortisol criteria. However, 95% of apparent "failed" baseline cortisol sets still showed lateralization of A/C ratios that matched the ultimate pathology. Non-ACTH-stimulated samples may be incorrectly judged as failed catheter placement when a 3:1 ratio is used. ACTH-stimulated sampling is the preferred means to confirm catheterization during AVS.

  20. Occult secretion of acth and bilateral adrenalectomy: sometimes the messenger has to be shot.

    PubMed

    Chicharro, Sandra; Lecube, Albert; Mesa, Jordi

    2008-12-01

    Cushing's syndrome due to ectopic adrenocorticotrophic hormone (ACTH) secretion is infrequent, the most frequent cause being bronchial carcinoid; nevertheless, in a considerable proportion of cases (up to 16%), the origin of ACTH secretion is not found. Treatment of Cushing's syndrome due to ectopic ACTH secretion is surgical resection of the tumor. However, surgical excision is not always feasible, either because the tumor has not been located, or because it is unresectable; in these cases the question is when to carry out a bilateral adrenalectomy. We present a case of ACTH-dependent hypercortisolism, in which the ectopic origin of ACTH secretion was established from the results of complementary tests (suppression tests, petrosal sinus sampling, imaging); nevertheless, none of the imaging tests was able to identify the secreting tumor. Consequently, after a reasonable interval, a bilateral adrenalectomy was performed, with good clinical results.

  1. The role of ACTH and glucocorticoids in nonenzymatic fibrinolysis during immobilization stress in animals

    NASA Technical Reports Server (NTRS)

    Kudryashov, B. A.; Shapiro, F. B.; Lomovskaya, E. G.; Lyapina, L. A.

    1980-01-01

    The role of the altered hormonal status of an organism in the activation of the anticoagulative system during stress is investigated. The 30 minute immobilization stress was shown to raise significantly the nonenzymatic fibrinolytic activity of blood in rats. Combined with adrenocorticotropin (ACTH) the effect is still greater. Intravenous administration of 0.2 m1 0.01 percent solution of protamine sulphate prevented the nonenzymatic fibrinolysis induced by the stress. Administration of ACTH after protomine sulphate again raised the fibrinolysis. This suggests that ACTH stimulates the release of heparin.

  2. ACTH and. cap alpha. -melanotropin in central temperature control

    SciTech Connect

    Lipton, J.M.; Glyn, J.R.; Zimmer, J.A.

    1981-11-01

    Adrenocorticotropin (ACTH) and ..cap alpha..-melanotropin (..cap alpha..-MSH) occur in brain tissue known to be important to temperature control. These peptides cause hypothermia if they are injected centrally in sufficient doses, but they do not act on the central set point of temperature control. Instead they appear to inhibit central pathways for heat conservation and production. In addition to their hypothermic capability, these peptides are antipyretic when given centrally in doses that have no effect on normal body temperature. ACTH has previously been associated with fever reduction in both clinical and experimental studies, and it may be that endogenous central ACTH is important for limitation of maximal fever. The hypothermic and antipyretic effects of ACTH do not depend on stimulation of the adrenal cortex because they are also observed in adrenalectomized rabbits. Nor is the antipyretic effect limited to the rabbit inasmuch as a comparable effect has been demonstrated in the squirrel monkey. The two peptides may be involved in central mediation of normal thermoregulation and fever, perhaps limiting the febrile response and other rises in body temperature by acting as neurotransmitters or neuromodulators in central thermoregulatory pathways.

  3. Aberrant expression of glucagon receptors in adrenal glands of a patient with Cushing's syndrome and ACTH-independent macronodular adrenal hyperplasia.

    PubMed

    de Miguel, Valeria; Redal, María Ana; Viale, María Lorena; Kahan, Mariano; Glerean, Mariela; Beskow, Axel; Fainstein Day, Patricia

    2010-01-01

    Adrenocorticotropin (ACTH) independent bilateral macronodular adrenal hyperplasia (AIMAH) is a rare cause of Cushing's syndrome, characterized by bilateral adrenal lesions and excess cortisol production despite ACTH suppression. Cortisol synthesis is produced in response to abnormal activation of G-protein-coupled receptors, such as gastric inhibitory peptide, vasopressin, beta adrenergic agonists, LH/hCG and serotonin receptors. The aim of this study was to analyze the expression of glucagon receptors in adrenal glands from an AIMAH patient. A patient with ACTH-independent Cushing's syndrome and bilateral macronodular adrenal hyperplasia was screened for altered activation of adrenal receptors by physiological (mixed meal) and pharmacological (gonadotrophin releasing hormone, ACTH and glucagon) tests. The results showed abnormally high levels of serum cortisol after stimulation with glucagon. Hypercortisolism was successfully managed with ketoconazole treatment. Interestingly, a 4-month treatment with a somatostatin analogue (octreotide) was also able to reduce cortisol secretion. Finally, Cushing's syndrome was cured after bilateral adrenalectomy. Abnormal mRNA expression for glucagon receptor in the patient's adrenal glands was observed by Real-Time PCR procedure. These results strongly suggest that the mechanism of AIMAH causing Cushing's syndrome in this case involves the illicit activation of adrenal glucagon receptors. This is the first case reported of AIMAH associated with ectopic glucagon receptors.

  4. Effects of cocaine and corticotropin-releasing factor on pulsatile ACTH and cortisol release in ovariectomized rhesus monkeys.

    PubMed

    Sarnyai, Z; Mello, N K; Mendelson, J H; Nguyen, P H; Erös-Sarnyai, M

    1995-09-01

    Cocaine stimulates ACTH secretion by a corticotropin-releasing factor (CRF)-dependent mechanism in male rats, rhesus monkeys, and humans. To determine the generality of this effect, we examined the effects of acute cocaine administration on the pulsatile release of ACTH and cortisol in three ovariectomized (OVX) rhesus monkeys and compared its effects to stimulation with CRF. Venous blood samples were collected at 2-min intervals for 60 min before and after iv administration of cocaine (0.4 and 0.8 mg/kg) and CRF (1.0 and 10 micrograms/kg). Cluster analysis procedures were used to evaluate the pulsatile characteristics of ACTH and cortisol release. After placebo administration, an ACTH pulse frequency of 3 peaks/h was detected. After cocaine administration, plasma cocaine levels peaked at 92 +/- 3.0 and 201 +/- 60 ng/mL within 2 min. However, in contrast to normal intact males, cocaine did not stimulate the pulsatile release of ACTH in OVX females. Cocaine (0.4 mg/kg) decreased ACTH incremental peak height and valley levels compared with pre-cocaine values, and a higher dose of cocaine produced no changes in ACTH release. Bolus injection of a low dose of CRF (1.0 micrograms/kg, iv) significantly increased ACTH incremental peak height (P < 0.05), and a higher dose of CRF (10 micrograms/kg) increased ACTH peak amplitude, percentage increase in peak amplitude, area under the peaks, and incremental peak heights as well as ACTH valley level and nadir (10 micrograms/kg, iv) (P < 0.05). ACTH pulse frequency did not change after CRF or cocaine administration. Pulsatile release of cortisol was 2.7 peaks/h under placebo conditions and did not change after cocaine or CRF administration. Cortisol pulse amplitude was increased after low and high doses of CRF. High doses of CRF (10 micrograms/kg) also increased the mean level of cortisol valleys. In summary, we found that CRF but not cocaine stimulated pulsatile ACTH and cortisol release in OVX rhesus monkeys. The profound ACTH

  5. Aging of the rat adrenocortical cell: response to ACTH and cyclic AMP in vitro.

    PubMed

    Malamed, S; Carsia, R V

    1983-03-01

    To study intrinsic age-related changes in adrenocortical steroid production, cells isolated from rats of different ages (3 to 24 months) were used. Acute (2 hour) corticosterone production in response to stimulation by adrenocorticotrophic hormone (ACTH) and adenosine 3':5'-cyclic monophosphate (cAMP) was measured by radioimmunoassay. With age, adrenocortical cells lose much of their ability to produce corticosterone in the absence or presence of ACTH or cAMP. The loss is progressive from 6 to 24 months of age. Analysis of the data suggests that from 6 to 12 months, an intracellular steroidogenic lesion develops; in addition there may be a loss in ACTH receptors on the plasma membrane. After 12 months these defects increase and are accompanied by a decrease in receptor sensitivity to ACTH.

  6. Corticotropin (ACTH)-reactive immunoglobulins in adolescents in relation to antisocial behavior and stress-induced cortisol response. The TRAILS study.

    PubMed

    Schaefer, Johanna M; Fetissov, Serguei O; Legrand, Romain; Claeyssens, Sophie; Hoekstra, Pieter J; Verhulst, Frank C; Van Oort, Floor V A

    2013-12-01

    Elevated levels of corticotropin (ACTH)-reactive immunoglobulins (ACTH IgG) were found in males with conduct disorder, suggesting their involvement in the biology of antisocial behavior. We first aimed to confirm these findings in a large general population sample of adolescents. Secondly, we studied the association between ACTH IgG levels and hypothalamic-pituitary-adrenal (HPA) axis response to stress. Free and total ACTH IgG levels were measured in sera of 1230 adolescents (15-18 years). HPA axis activity was determined by measuring salivary cortisol before, during, and after a social stress test. Antisocial behavior was assessed using the Antisocial Behavior Questionnaire. ACTH peptide and IgG affinity kinetics for ACTH were assayed in a subsample of 90 adolescents selected for high or low ACTH IgG levels. In boys, higher total ACTH IgG levels were associated with higher antisocial behavior scores (β=1.05, p=0.04), especially at high levels of free ACTH IgG. In girls, antisocial behavior was associated with low free ACTH IgG levels (β=-0.20, p=0.04). Stress-induced cortisol release was associated with free ACTH IgG in boys (βareaunderthecurve=-0.67, p<0.01), and with total ACTH IgG in girls (βrecovery=0.84, p=0.05). The affinity kinetics assay showed that ACTH IgG association rates were lower in both boys and girls with high ACTH IgG levels. These data show that ACTH IgG levels are related to antisocial behavior and HPA axis response to stress in adolescents. The mechanisms behind these associations, including different ACTH binding properties of IgG in subjects with antisocial behavior, deserve further attention.

  7. Calibration and Testing of Sonic Stimulation Technologies

    SciTech Connect

    Roger M. Turpening; Wayne D.Pennington

    2005-03-31

    In conjunction with Baker Atlas Inc. Michigan Technological University devised a system capable of recording the earth motion and pressure due to downhole and surface seismic sources. The essential elements of the system are 1) a borehole test site that will remain constant and is available all the time and for any length of time, 2) a downhole sonde that will itself remain constant and, because of its downhole digitization feature, does not require the wireline or surface recording components to remain constant, and 3) a set of procedures that ensures that the amplitude and frequency parameters of a wide range of sources can be compared with confidence. This system was used to record four seismic sources, three downhole sources and one surface source. A single activation of each of the downhole sources was not seen on time traces above the ambient noise, however, one sweep of the surface source, a small vertical vibrator, was easily seen in a time trace. One of the downhole sources was seen by means of a spike in its spectrum and a second downhole source was clearly seen after correlation and stacking. The surface vibrator produced a peak to peak particle motion signal of approximately 4.5 X 10-5 cm/sec and a peak to peak pressure of approx. 2.5 X 10-7 microPascals at a depth of 1,485 ft. Theoretical advances were made with our partner, Dr. I. Beresnev at Iowa State University. A theory has been developed to account for the behavior of oil ganglia trapped in pore throats, and their ultimate release through the additional incremental pressure associated with sonic stimulation.

  8. CALIBRATION AND TESTING OF SONIC STIMULATION TECHNOLOGIES

    SciTech Connect

    Roger Turpening; Wayne Pennington; Christopher Schmidt; Sean Trisch

    2005-03-01

    In conjunction with Baker Atlas Inc. Michigan Technological University devised a system capable of recording the earth motion and pressure due to downhole and surface seismic sources. The essential elements of the system are (1) a borehole test site that will remain constant and is available all the time and for any length of time, (2) a downhole sonde that will itself remain constant and, because of its downhole digitization feature, does not require the wireline or surface recording components to remain constant, and (3) a set of procedures that ensures that the amplitude and frequency parameters of a wide range of sources can be compared with confidence. This system was used to record four seismic sources, three downhole sources and one surface source. A single activation of each of the downhole sources was not seen on time traces above the ambient noise, however, one sweep of the surface source, a small vertical vibrator, was easily seen in a time trace. One of the downhole sources was seen by means of a spike in its spectrum and a second downhole source was clearly seen after correlation and stacking. The surface vibrator produced a peak to peak particle motion signal of approximately 4.5 x 10{sup -5} cm/sec and a peak to peak pressure of approx. 2.5 x 10{sup -7} microPascals at a depth of 1,485 ft. Theoretical advances were made with our partner, Dr. Igor Beresnev at Iowa State University. A theory has been developed to account for the behavior of oil ganglia trapped in pore throats, and their ultimate release through the additional incremental pressure associated with sonic stimulation.

  9. Testosterone, estradiol, ACTH and musical, spatial and verbal performance.

    PubMed

    Hassler, M; Gupta, D; Wollmann, H

    1992-01-01

    Testosterone, estradiol, and ACTH were determined in blood serum of 26 healthy males aged 19.16 and of 25 healthy females aged 18.77 years on average, and results were correlated with test scores of three spatial tests, a verbal fluency measure, and a test measuring general musical ability. In addition, hemispheric lateralization for verbal material and handedness was assessed. While testosterone and estradiol alone were not significantly related to any of the cognitive or musical tests, testosterone/estradiol ratio was significantly negatively correlated with spatial tests, and ACTH was significantly positively correlated with spatial and musical tests. Correlations were stronger in females than in males. The laterality index was significantly negatively correlated with testosterone in males indicating that right hemisphere involvement in verbal processing was associated with high testosterone levels.

  10. The Potential of ACTH in the Genesis of Primary Aldosteronism.

    PubMed

    Funder, John W

    2016-01-01

    Aldosterone is a homeostatic hormone, rising in volume depletion, sodium deficiency, and potassium loading, in response to angiotensin11 and elevation of plasma potassium. Pathophysiologically, in primary aldosteronism (PA) aldosterone levels are inappropriate for the patient's sodium and potassium status, and thus outside the normal feedback loop. ACTH is equivalent with A11 and [K(+)] in elevating aldosterone: its effects differ from those of the other secretagogues in four ways. First, it is not sustained; second, it raises aldosterone and cortisol secretion with equal potency; third, it is outside the normal feedback loops, reflecting the epithelial action of aldosterone; and finally its possible role in driving inappropriate aldosterone secretion (aka PA) is not widely recognized. Thirty years ago, it was shown that on a fixed sodium intake of 175 meq/day 36 of 100 unselected hypertensives, in whom PA has been excluded on contemporary criteria, had 24 h urinary aldosterone levels above the upper limit of normotensive controls. More recently, the dexamethasone enhanced fludrocortisone suppression test (FDST) showed 29% of unselected hypertensives to have plasma aldosterone concentrations above the upper limit of normotensive controls. In subjects negative for PA on the FDST, 27% were extremely hyper-responsive to ultra-low dose ACTH infusion; the remaining 73% showed minimal aldosterone elevation, as did normotensive controls: all three groups had negligible cortisol responses. On treadmill testing, no differences were found between groups in (minimally altered) ACTH and cortisol levels: hyper-responders to ultra-low ACTH, however, showed a major elevation in PAC. The implications of these studies, when validated, are substantial for PA, in that approximately half of hypertensive patients appear to show inappropriate aldosterone levels for their sodium status. The physiological role(s) of ACTH as an acute aldosterone secretagogue, and the mechanisms whereby

  11. The Potential of ACTH in the Genesis of Primary Aldosteronism

    PubMed Central

    Funder, John W.

    2016-01-01

    Aldosterone is a homeostatic hormone, rising in volume depletion, sodium deficiency, and potassium loading, in response to angiotensin11 and elevation of plasma potassium. Pathophysiologically, in primary aldosteronism (PA) aldosterone levels are inappropriate for the patient’s sodium and potassium status, and thus outside the normal feedback loop. ACTH is equivalent with A11 and [K+] in elevating aldosterone: its effects differ from those of the other secretagogues in four ways. First, it is not sustained; second, it raises aldosterone and cortisol secretion with equal potency; third, it is outside the normal feedback loops, reflecting the epithelial action of aldosterone; and finally its possible role in driving inappropriate aldosterone secretion (aka PA) is not widely recognized. Thirty years ago, it was shown that on a fixed sodium intake of 175 meq/day 36 of 100 unselected hypertensives, in whom PA has been excluded on contemporary criteria, had 24 h urinary aldosterone levels above the upper limit of normotensive controls. More recently, the dexamethasone enhanced fludrocortisone suppression test (FDST) showed 29% of unselected hypertensives to have plasma aldosterone concentrations above the upper limit of normotensive controls. In subjects negative for PA on the FDST, 27% were extremely hyper-responsive to ultra-low dose ACTH infusion; the remaining 73% showed minimal aldosterone elevation, as did normotensive controls: all three groups had negligible cortisol responses. On treadmill testing, no differences were found between groups in (minimally altered) ACTH and cortisol levels: hyper-responders to ultra-low ACTH, however, showed a major elevation in PAC. The implications of these studies, when validated, are substantial for PA, in that approximately half of hypertensive patients appear to show inappropriate aldosterone levels for their sodium status. The physiological role(s) of ACTH as an acute aldosterone secretagogue, and the mechanisms whereby

  12. Interaction between Dax-1 and steroidogenic factor-1 in vivo: increased adrenal responsiveness to ACTH in the absence of Dax-1.

    PubMed

    Babu, Poda Suresh; Bavers, David L; Beuschlein, Felix; Shah, Sonalee; Jeffs, Baxter; Jameson, J Larry; Hammer, Gary D

    2002-02-01

    Two nuclear receptors, dosage-sensitive sex reversal adrenal hypoplasia congenita, critical region on the X chromosome gene-1 (Dax-1) and steroidogenic factor-1 (SF-1), are required for adrenal development and function. In vitro assays suggest that Dax-1 represses SF-1 mediated transcription. In this study, we generated SF-1(+/-): Dax-1(-/Y) mice to examine the role of Dax-1 in SF-1-dependent steroidogenesis in vivo. While the SF-1 expression was impaired in SF-1(+/-) mice, there was no change in Dax-1 expression in SF-1(+/-) mice and no change in SF-1 expression in Dax-1(-/Y) mice. SF-1(+/-) mice had small adrenal glands with adrenal hypoplasia and cellular hypertrophy. The loss of Dax-1 in SF-1(+/-): Dax-1(-/Y) mice reversed the decreased adrenal weight and histological abnormalities observed in SF-1(+/-) mice. SF-1(+/-) mice had elevated ACTH and the lowest corticosterone following restraint stress. In contrast, Dax-1(-/Y) mice had elevated corticosterone and decreased ACTH. Adrenal responsiveness (ACTH/corticosterone) was highest in Dax-1(-/Y) mice, intermediate in WT and SF-1(+/-): Dax-1(-/Y) mice, and lowest in SF-1(+/-) mice. In accordance with these findings, ACTH stimulation testing resulted in the highest levels of corticosterone in the Dax-1(-/Y) mice. Protein levels of P450c21 and the ACTH receptor were increased in Dax-1(-/Y) mice and intermediate in SF-1(+/-): Dax-1(-/Y) mice following chronic food deprivation. These results are consistent with a model in which Dax-1 functions to inhibit SF-1-mediated steroidogenesis in vivo. PMID:11796523

  13. FSH (Follicle-Stimulating Hormone) Test

    MedlinePlus

    ... FSH and LH may be ordered when a boy or girl does not appear to be entering puberty at ... hair Growth of the testicles and penis in boys Beginning of menstruation in girls ^ Back to top What does the test result ...

  14. Ectopic ACTH Production in Carcinoma of the Lung

    PubMed Central

    Gewirtz, George; Yalow, Rosalyn S.

    1974-01-01

    Immunoreactive ACTH was found in almost all tissue extracts of lung carcinoma from patients without clinical evidence of Cushing's syndrome; i.e. 14 of 15 primary tumors, nine of nine metastatic lymph nodes, and four of four metastatic liver nodules contained immunoreactive ACTH. The incidence of ACTH in extracts of other tumor types was much lower. Comparable normal tissues contained no detectable ACTH. Immunoreactive growth hormone, parathyroid hormone, or gastrin was not found in the same carcinoma tissue. The predominant form of ACTH in the tumor extracts was big ACTH. In pituitary extracts little ACTH predominated. 53% of 83 patients with lung carcinoma had afternoon plasma ACTH levels greater than 150 pg/ml; more than 90% of plasmas containing less than 150 pg/ml were obtained from patients who had received radiation therapy or chemotherapy. 31% of 45 patients with chronic obstructive pulmonary disease (COPD), 28% of 25 patients with other severe lung disease, and 6% of 33 controls had elevated values. Big ACTH predominated in the plasma of patients with lung carcinoma or COPD having elevated ACTH levels. Tissue from the lung of a smoking dog with atypical histologic changes contained immunoreactive ACTH, almost exclusively in the big form, while tissue from another smoking dog that was histologically normal contained no ACTH. Thus ACTH may be present even in precancerous lung lesions. These studies suggest that serial plasma ACTH levels may be of value in screening for, and/or management of, patients with carcinoma of the lung. PMID:4360854

  15. Melanocortin receptor agonist ACTH 1-39 protects rat forebrain neurons from apoptotic, excitotoxic and inflammation-related damage.

    PubMed

    Lisak, Robert P; Nedelkoska, Liljana; Bealmear, Beverly; Benjamins, Joyce A

    2015-11-01

    Patients with relapsing-remitting multiple sclerosis (RRMS) are commonly treated with high doses of intravenous corticosteroids (CS). ACTH 1-39, a member of the melanocortin family, stimulates production of CS by the adrenals, but melanocortin receptors are also found in the central nervous system (CNS) and on immune cells. ACTH is produced within the CNS and may have direct protective effects on glia and neurons independent of CS. We previously reported that ACTH 1-39 protected oligodendroglia (OL) and their progenitors (OPC) from a panel of excitotoxic and inflammation-related agents. Neurons are the most vulnerable cells in the CNS. They are terminally differentiated, and sensitive to inflammatory and excitotoxic insults. For potential therapeutic protection of gray matter, it is important to investigate the direct effects of ACTH on neurons. Cultures highly enriched in neurons were isolated from 2-3 day old rat brain. After 4-7 days in culture, the neurons were treated for 24h with selected toxic agents with or without ACTH 1-39. ACTH 1-39 protected neurons from death induced by staurosporine, glutamate, NMDA, AMPA, kainate, quinolinic acid, reactive oxygen species and, to a modest extent, from rapidly released NO, but did not protect against kynurenic acid or slowly released nitric oxide. Our results show that ACTH 1-39 protects neurons in vitro from several apoptotic, excitotoxic and inflammation-related insults.

  16. Loss of sensitivity to ACTH of adrenocortical cells isolated from maturing domestic fowl.

    PubMed

    Carsia, R V; Scanes, C G; Malamed, S

    1985-07-01

    Maturation of domestic fowl corticosteroidogenesis was evaluated using purified adrenocortical cells. Basal corticosterone production decreased steadily from 2 days to 26 weeks after hatching. However, maximally stimulated corticosterone production was not changed. In contrast, the half-maximal steroidogenic concentrations (ED50 values or effective doses for 50% maximal effect) of ACTH analogs increased approximately 40 times by 26 weeks, but the ED50 values of 8-bromo-cyclic AMP and pregnenolone were not changed. This suggests that adrenocortical cell sensitivity to ACTH decreases with maturation of the domestic fowl.

  17. ACTH adenomas transforming their clinical expression: report of 5 cases.

    PubMed

    Zoli, Matteo; Faustini-Fustini, Marco; Mazzatenta, Diego; Marucci, Gianluca; De Carlo, Eugenio; Bacci, Antonella; Pasquini, Ernesto; Lanzino, Giuseppe; Frank, Giorgio

    2015-02-01

    OBJECT Adrenocorticotropic hormone (ACTH) adenomas have been recognized as a more aggressive and invasive subtype of pituitary adenomas. An additional and clinically relevant peculiarity of these tumors is their ability to modify their clinical expression from a silent form to Cushing disease or vice versa. The aim of this study was to review a series of patients with pituitary adenomas and analyze the clinical implications of the transformation of clinical expression in 5 cases that showed this phenomenon. METHODS The authors retrospectively reviewed a series of patients with pituitary adenoma and collected clinical, biohumoral, and neuroradiological data of those who presented with a transformation from silent ACTH adenomas to functioning tumors or vice versa. In all the cases, preoperative assessment consisted of brain MRI, ophthalmological examination, and complete baseline endocrinological investigation. In patients with clinical and/or biochemical findings suspicious for Cushing syndrome, a low-dose dexamethasone suppression test was performed to rule in or out this diagnosis. Endocrinological evaluations were repeated 1 month after surgery, 3 months after surgery, and every 6 months or annually thereafter. Ophthalmological evaluations and brain MRIs were repeated after 3 months and then every 6 or 12 months thereafter. RESULTS Five patients (2 men and 3 women) included in this series had corticotropic tumors that showed transformation from an endocrinologically silent form to manifest Cushing disease and vice versa. The mean age at presentation was 40 years (range 18-51 years). In 3 of these patients, a transformation from silent to functioning ACTH adenoma with manifest Cushing disease occurred. In 1 patient, the authors observed the transition from a functioning to a silent adenoma with spontaneous resolution of hypercortisolism. Another patient's silent adenoma "shifted" to a functioning adenoma and then regressed back to a silent form with spontaneous

  18. Effects of mastoparan upon the late stages of the ACTH secretory pathway of AtT-20 cells.

    PubMed Central

    McFerran, B. W.; Guild, S. B.

    1995-01-01

    1. The mouse AtT-20/D16-16 anterior pituitary tumour cell line was used as a model system for the study of the effects of mastoparan upon the late stages of the adrenocorticotrophin (ACTH) secretory pathway. 2. Mastoparan (10(-8)-10(-5) M), an activator of heterotrimeric guanosine 5'-triphosphate binding proteins (G-proteins), stimulated ACTH secretion from electrically-permeabilized AtT-20 cells in a concentration-dependent manner in the effective absence of calcium ions with a threshold of 10(-6) M. Guanosine 5'-O-(3-thiotriphosphate) (GTP-gamma-S) (10(-8)-10(-4) M) also stimulated ACTH secretion from electrically-permeabilized AtT-20 cells in a concentration-dependent manner in the effective absence of calcium ions with a threshold of 10(-6) M. This GTP-gamma-S-evoked secretion is consistent with previous studies which demonstrated that a G-protein, termed GE, mediates calcium evoked ACTH secretion from AtT-20 cells. GTP-gamma-S-evoked secretion however was not as great as that obtained in response to mastoparan. 3. Both mastoparan (10(-5) M) and GTP-gamma-S (10(-4) M) stimulated ACTH secretion from electrically-permeabilized AtT20 cells in a time-dependent manner. A time of 30 min was adopted as the standard incubation period for the study of both mastoparan and GTP-gamma-S-stimulated ACTH secretion from permeabilized AtT-20 cells. 4. Mastoparan (10(-8)-10(-5) M) stimulated ACTH secretion from permeabilized AtT-20 cells to the same extent in the presence and absence of the protein kinase C (PKC) inhibitor, chelerythrine chloride (10(-5) M).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7582493

  19. The role of ACTH and adrenal glucocorticoids in the salt appetite of wild rabbits (Oryctolagus cuniculus (L)).

    PubMed

    Blaine, E H; Covelli, M D; Denton, D A; Nelson, J F; Shulkes, A A

    1975-10-01

    The selective appetites of wild rabbits for 500 mEq/1 solutions of NaC1, KC1, MgC1(2), and CaC1(2) were studied in intact and adrenalectomized rabbits during daily treatment with either 4 IU long acting ACTH, 1.0 or 2.5 mg cortisol acetate, or 2.5 mg corticosterone. The animals were individually caged and external sodium balances performed. In intact rabbits, cortisol or corticosterone produced a significant stimulation of NaC1 appetite. The response to concurrent dosage of cortisol and corticosterone was less than half of that obtained with ACTH which produced a comparable alteration of blood glucocorticoid levels but a 10-fold increase in NaC1 intake. CaC1(2) intake was increased in intact rabbits by cortisol treatment but not by corticosterone or ACTH. Adrenalectomized rabbits maintained on daily steroid replacement therapy of 0.1 mg deoxycorticosterone acetate and 0.75 mg cortisone acetate showed a normal pattern of electolyte, food, and water intake. Under these conditions ACTH produced a 4-fold increase in NaC1 intake. Further addition of cortisol and corticosterone to steroid replacement therapy produced an increase in NaC1 intake comparable to their effect on normal rabbits. Thereupon supplementation with ACTH resulted in an increase to a level at least as great as that found in ACTH treated, normal rabbits. The effects of ACTH and glucocorticoids on NaC1 appetite were synergistic. Sodium balance showed that increases in NaC1 intake were not the result of the treatment initially producing a body sodium deficit, which was then corrected by increased intake. The results provide further evidence for the hypothesis that NaC1 appetite may be hormonally regulated, and demonstrate that ACTH is capable of stimulating NaC1 intake by a previously unsuspected non-adrenal pathway.

  20. Modified dexamethasone suppression-corticotropin-releasing hormone stimulation test: A pilot study of young healthy volunteers and implications for alcoholism research in adolescents and young adults.

    PubMed

    Sher, Leo; Cooper, Thomas B; Mann, J John; Oquendo, Maria A

    2006-01-01

    The key neuroendocrine component of a response to stress is the hypothalamic-pituitary-adrenocortical (HPA) system. Abnormalities in the HPA system have been implicated in the pathophysiology of psychiatric disorders such as depression, post-traumatic stress disorder, alcoholism and suicide. The dexamethasone suppression test (DST) is the most frequently used test to assess HPA-system function in psychiatric disorders. This neuroendocrine test consists of the administration of a low dose of dexamethasone at 11 pm and the measurement of cortisol levels at one or more time points on the following day. After corticotropin-releasing hormone (CRH) became available for clinical studies, the DST was combined with CRH administration. In this test, patients are pretreated with a single dose of dexamethasone at 11 pm and receive human CRH intravenously at 3 pm the following day. The resulting DST-CRH test proved to be much more sensitive in detecting HPA system alterations than the DST. We have modified the DST-CRH test and used ovine CRH instead of human CRH in a pilot study of a group of young healthy volunteers. Results indicated that it produces results similar to the results obtained with human CRH. This suggests that ovine CRH can be used in psychiatric research. Alcoholism is associated with abnormalities in HPA function. Nonalcoholic subjects with a family history of alcoholism exhibit lower plasma ACTH and beta-endorphin as well as lower ACTH, cortisol, and beta-endorphin responses to psychological stress and CRH stimulation. This suggests that in children of alcoholics, alterations in the mechanisms that regulate HPA axis activity predate the development of alcohol dependence and may be considered inherited traits. Therefore, studies of the HPA system in persons at risk for alcoholism may help understand the neurobiological mechanisms of predisposition to alcoholism.

  1. Motion sickness susceptibility related to ACTH, ADH and TSH

    NASA Technical Reports Server (NTRS)

    Kohl, R. L.; Leach, C.; Homick, J. L.; Larochelle, F. T.

    1983-01-01

    The hypothesis that endogenous levels of certain hormones might be indicative of an individual's susceptibility to stressful motion is tested in a comparison of subjects classified as less prone to motion sickness with those of higher susceptibility. The levels of ACTH and vasopressin measured before exposure to stressful motion were twice as high in the less-suceptible group. No significant differences were noted in the levels of angiotensin, aldosterone, or TSH. The differences between the two groups were greater for a given hormone than for any of the changes induced by exposure to stressful motion.

  2. Reliability of psychophysiological responses across multiple motion sickness stimulation tests

    NASA Technical Reports Server (NTRS)

    Stout, C. S.; Toscano, W. B.; Cowings, P. S.

    1995-01-01

    Although there is general agreement that a high degree of variability exists between subjects in their autonomic nervous system responses to motion sickness stimulation, very little evidence exists that examines the reproducibility of autonomic responses within subjects during motion sickness stimulation. Our objectives were to examine the reliability of autonomic responses and symptom levels across five testing occasions using the (1) final minute of testing, (2) change in autonomic response and the change in symptom level, and (3) strength of the relationship between the change in symptom level and the change in autonomic responses across the entire motion sickness test. The results indicate that, based on the final minute of testing, the autonomic responses of heart rate, blood volume pulse, and respiration rate are moderately stable across multiple tests. Changes in heart rate, blood volume pulse, respiration rate, and symptoms throughout the test duration are less stable across the tests. Finally, autonomic responses and symptom levels are significantly related across the entire motion sickness test.

  3. A case of ACTH-independent bilateral macronodular adrenal hyperplasia and severe congestive heart failure.

    PubMed

    Suri, D; Alonso, M; Weiss, R E

    2006-11-01

    Cortisol secretion in ACTH independent bilateral macronodular adrenal hyperplasia (AIMAH) can be regulated by aberrant adrenal receptors. We describe a patient with Cushing's syndrome (CS) due to AIMAH and concomitant Class IV congestive heart failure (CHF). Clinical testing for the presence of aberrant receptors revealed a pronounced serum cortisol (257%) and aldosterone response (212%) to the administration of ACTH and a partial serum cortisol (35%) and aldosterone (106%) response to upright posture. This suggested the possible presence of aberrant hormone receptors for ACTH [melanocortin 2 receptor (MC2-R)], vasopressin, catecholamines or angiotensin II (AT-II) on the patient's adrenal glands. Adrenal tissue from the patient demonstrated an eight-fold increased expression of MC2-R compared to normal adrenal tissue. This increased expression was consistent with the increase in cortisol and aldosterone seen in response to exogenous ACTH. We propose that the severe CHF resulted in activation of the renin-angiotensin system, with an increased production of AT-II. The elevated circulating levels of AT-II may have led to increased expression of MC2-R on the patient's adrenal glands and increased responsiveness to ACTH. This unusual case of CS may elucidate a heretofore unknown mechanism for the development of AIMAH.

  4. 21 CFR 862.1300 - Follicle-stimulating hormone test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Follicle-stimulating hormone test system. 862.1300... Systems § 862.1300 Follicle-stimulating hormone test system. (a) Identification. A follicle-stimulating hormone test system is a device intended to measure follicle-stimulating hormone (FSH) in plasma,...

  5. 21 CFR 862.1300 - Follicle-stimulating hormone test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Follicle-stimulating hormone test system. 862.1300... Systems § 862.1300 Follicle-stimulating hormone test system. (a) Identification. A follicle-stimulating hormone test system is a device intended to measure follicle-stimulating hormone (FSH) in plasma,...

  6. 21 CFR 862.1300 - Follicle-stimulating hormone test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Follicle-stimulating hormone test system. 862.1300... Systems § 862.1300 Follicle-stimulating hormone test system. (a) Identification. A follicle-stimulating hormone test system is a device intended to measure follicle-stimulating hormone (FSH) in plasma,...

  7. 21 CFR 862.1300 - Follicle-stimulating hormone test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Follicle-stimulating hormone test system. 862.1300... Systems § 862.1300 Follicle-stimulating hormone test system. (a) Identification. A follicle-stimulating hormone test system is a device intended to measure follicle-stimulating hormone (FSH) in plasma,...

  8. 21 CFR 862.1300 - Follicle-stimulating hormone test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Follicle-stimulating hormone test system. 862.1300... Systems § 862.1300 Follicle-stimulating hormone test system. (a) Identification. A follicle-stimulating hormone test system is a device intended to measure follicle-stimulating hormone (FSH) in plasma,...

  9. [Cushing syndrome due to ectopic ACTH secretion].

    PubMed

    Mendonça, B B; Madureira, G; Bloise, W; Albergaria, A; Halpern, A; Liberman, B; Villares, S M; Batista, M C; Avancini, V F; Nitterdorfi, C T

    1989-01-01

    The authors studied 8 patients (4 males and 4 females) with Cushing's syndrome due to ectopic ACTH secretion. Chronological age ranged from 15 to 45 years and duration of the disease ranged from 3 to 48 months. All patients presented typical signs of Cushing's syndrome, blood hypertension, and four of them had hyperpigmentation of the skin. Five patients had fasting hyperglycemia and all patients but one had serum hypokalemia (serum K = 2.2 to 3.9mEq/l). The circadian rhythm of cortisol was absent in all patients and basal cortisol levels were elevated in all patients but one. Basal ACTH levels evaluated in 7 patients were elevated in 6 (29 to 1050 pg/ml-MRC). One patient presented normal depression of urinary 17-OH after two days of dexamethasone and normal increase of urinary 17-OH and serum 11-dexycortisol after methyrapone. Four patients had carcinoid tumor (3 thymic and 1 bronchial), two had pancreatic islets cell tumors, one had bilateral pheochromocytoma and medular carcinoma of the thyroid, and one had oat cell carcinoma of the lung and medular carcinoma of the thyroid. Thoracic X-rays identified the ectopic ACTH secretion tumor in four cases, all confirmed by CT scan. Abdominal CT showed a difuse enlargement of the adrenals in seven cases and bilateral nodules in one case (pheochromocytomas). Six patients died within 3 years of the diagnosis. The authors concluded that clinical and hormonal findings could mislead the findings of ACTH ectopic secretion and Cushing's disease, and suggest that thoracic X-rays and CT scans of the skull, thorax, and abdome should be done in all cases of Cushing's syndrome. PMID:2559451

  10. Testosterone suppression of CRH-stimulated cortisol in men.

    PubMed

    Rubinow, David R; Roca, Catherine A; Schmidt, Peter J; Danaceau, Merry A; Putnam, Karen; Cizza, Giovanni; Chrousos, George; Nieman, Lynnette

    2005-10-01

    Despite observations of age-dependent sexual dimorphisms in hypothalamic-pituitary-adrenal (HPA) axis activity, the role of androgens in the regulation of HPA axis activity in men has not been examined. We assessed this role by performing CRH stimulation tests in 10 men (ages 18-45 years) during gonadal suppression with leuprolide acetate and during testosterone addition to leuprolide. CRH-stimulated cortisol levels as well as peak cortisol and greatest cortisol excursion were significantly lower (p<0.05, 0.005, and 0.01, respectively) during testosterone replacement compared with the induced hypogonadal condition (leuprolide plus placebo); cortisol area under the curve was lower at a trend level (p<0.1). Paradoxically, CRH-stimulated corticotropin (ACTH) was increased significantly during testosterone replacement (p<0.05). The cortisol : ACTH ratio, a measure of adrenal sensitivity, was lower during testosterone replacement (p<0.1). A mixed effects regression model showed that testosterone but not estradiol or CBG significantly contributed to the variance of cortisol. These data demonstrate that testosterone regulates CRH-stimulated HPA axis activity in men, with the divergent effects on ACTH and cortisol suggesting a peripheral (adrenal) locus for the suppressive effects on cortisol. Our results further demonstrate that the enhanced stimulated HPA axis activity previously described in young men compared with young women cannot be ascribed to an activational upregulation of the axis by testosterone.

  11. Stimulants

    MedlinePlus

    Stimulants are drugs that increase your heart rate, breathing rate, and brain function. Some stimulants affect only a specific organ, such as the heart, lungs, brain, or nervous system. Epinephrine is a stimulant. It ...

  12. Involvement of multiple protein kinase C isozymes in the ACTH secretory pathway of AtT-20 cells.

    PubMed Central

    McFerran, B. W.; MacEwan, D. J.; Guild, S. B.

    1995-01-01

    1. The mouse AtT-20/D16-16 anterior pituitary tumour cell line was used as a model system for the study of protein kinase C (PKC)-mediated enhancement of calcium- and guanine nucleotide-evoked adrenocorticotrophin (ACTH) secretion. 2. A profile of the PKC isozymes present in AtT-20 cells was obtained by Western blotting analysis and it was found that AtT-20 cells express the alpha, beta, epsilon and zeta isoforms of PKC. 3. PKC isozymes were activated by the use of substances reported to activate particular isoforms of the enzyme. The effects of these substances were investigated in both intact and electrically-permeabilized cells. Phorbol 12-myristate 13-acetate (PMA, EC50 = 1 +/- 0.05 nM, which activates all isozymes of PKC, except the zeta isozyme), thymeleatoxin (TMX, EC50 = 10 +/- 0.5 nM, which activates the alpha, beta and gamma isozymes) and 12-deoxyphorbol 13-phenylacetate 20-acetate (dPPA, EC50 = 3 +/- 0.5 nM, a beta 1-selective isozyme activator) all stimulated ACTH secretion from intact cells in a concentration-dependent manner. Maximal TMX stimulated ACTH secretion was of a similar degree to that obtained in response to PMA but maximal dPPA-stimulated ACTH secretion was only 60-70% of that obtained in response to PMA or TMX. 4. Calcium stimulated ACTH secretion from electrically-permeabilized cells over the concentration-range of 100 nM to 10 microM. PMA (100 nM), TMX (100 nM) but not dPPA (100 nM) enhanced the amount of ACTH secreted at every concentration of calcium investigated.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 1 PMID:7670732

  13. Acute effects of ACTH on dissociated adrenocortical cells: quantitative changes in mitochondria and lipid droplets.

    PubMed

    Zoller, L C; Malamed, S

    1975-08-01

    To study the role of certain organelles in steroidogenesis, dissociated rat adrenocortical cells were incubated for two hours with ACTH at a concentration that induces a high level of steroid production. Sections of ACTH treated and untreated cells were photographed in the electron microscope, and morphometric analysis was undertaken to assess possible ACTH-induced changes in total cell volume, volume density and numerical denisty of lipid droplets and mitochondria. There was no change in total cell volume. Lipid droplet volume density and numerical density decreased. Mitochondrial volume density did not change, but numerical density increased. The decrease in lipid droplet volume density indicates a rapid depletion of cholesterol for steroid production. This depletion is almost entirely due to the disappearance of lipid droplets, rather than to an overall diminution in their size, as shown by the decrease in lipid droplet numerical density. The mitochondrial data suggest that the adrenocortical cell has an adedquate mitochondrial apparatus to respond to acute ACTH stimulation with increased steroid output without an increase inmitochondrial volume.

  14. ACTH-induced caveolin-1 tyrosine phosphorylation is related to podosome assembly in Y1 adrenal cells.

    PubMed

    Colonna, Cecilia; Podestá, Ernesto J

    2005-04-01

    Y1 adrenocortical cells respond to ACTH with a characteristic rounding-up that facilitates cAMP signaling, critical for transport of cholesterol to the mitochondria and increase in steroid secretion. We here demonstrate that caveolin-1 participates in coupling activation of protein kinase A (PKA) to the control of cell shape. ACTH/8-Br-cAMP induced reorganization of caveolin-1-positive structures in correlation with the cellular rounding-up. Concomitant with this change, there was an increase in the phosphorylation of caveolin-1 (Tyr-14) localized at focal adhesions (FA) with reorganization of FA to rounded, ringlike structures. Colocalization with phalloidin showed that phosphocaveolin is present at the edge of actin filaments and that after ACTH stimulation F-actin dots at the cell periphery become surrounded by phosphocaveolin-1. These observations along with electron microscopy studies revealed these structures as podosomes. Podosome assembly was dependent on both PKA and tyrosine kinase activities because their formation was impaired after treatment with specific inhibitors [myristoylated PKI (mPKI) or PP2, respectively] previous to ACTH/8-Br-cAMP stimulation. These results show for the first time that ACTH induces caveolin-1 phosphorylation and podosome assembly in Y1 cells and support the view that the morphological and functional responses to PKA activation in steroidogenic cells are related to cytoskeleton dynamics.

  15. ACTH-induced caveolin-1 tyrosine phosphorylation is related to podosome assembly in Y1 adrenal cells

    SciTech Connect

    Colonna, Cecilia . E-mail: ccolonna@fmed.uba.ar; Podesta, Ernesto J.

    2005-04-01

    Y1 adrenocortical cells respond to ACTH with a characteristic rounding-up that facilitates cAMP signaling, critical for transport of cholesterol to the mitochondria and increase in steroid secretion. We here demonstrate that caveolin-1 participates in coupling activation of protein kinase A (PKA) to the control of cell shape. ACTH/8-Br-cAMP induced reorganization of caveolin-1-positive structures in correlation with the cellular rounding-up. Concomitant with this change, there was an increase in the phosphorylation of caveolin-1 (Tyr-14) localized at focal adhesions (FA) with reorganization of FA to rounded, ringlike structures. Colocalization with phalloidin showed that phosphocaveolin is present at the edge of actin filaments and that after ACTH stimulation F-actin dots at the cell periphery become surrounded by phosphocaveolin-1. These observations along with electron microscopy studies revealed these structures as podosomes. Podosome assembly was dependent on both PKA and tyrosine kinase activities because their formation was impaired after treatment with specific inhibitors [myristoylated PKI (mPKI) or PP2, respectively] previous to ACTH/8-Br-cAMP stimulation. These results show for the first time that ACTH induces caveolin-1 phosphorylation and podosome assembly in Y1 cells and support the view that the morphological and functional responses to PKA activation in steroidogenic cells are related to cytoskeleton dynamics.

  16. The thyrotropin releasing hormone stimulation test in alcoholism.

    PubMed

    Pienaar, W P; Roberts, M C; Emsley, R A; Aalbers, C; Taljaard, F J

    1995-09-01

    The mechanism for a blunted thyroid stimulating hormone (TSH) response to thyrotropin releasing hormone (TRH) in alcoholics is not known. We performed a combined TRH and gonadoliberin stimulation test on three well-defined groups of nondepressed alcoholic men. Group A comprised patients with acute withdrawal symptoms (n = 28), group B patients abstinent for 5-8 weeks (n = 29) and group C patients who had been abstinent for > 2 years (n = 16). Twenty-two healthy male volunteers were used for comparison. A blunted TSH response to TRH (delta TSH < 5 microU/l) occurred only in groups A (39%) and B (17%). In group A delta TSH showed a significant negative correlation with the severity of withdrawal symptoms and a significant positive correlation with serum magnesium levels. In group B, patients with a family history of alcoholism had significantly lower delta TSH levels than those without such a family history. Groups did not differ with respect to basal and delta prolactin, and TSH responses were not significantly associated with vitamin deficiency, cortisol levels or free thyroid hormone levels. We conclude that TRH stimulation test blunting appears to be related to factors operating in the withdrawal state and improves with continued abstinence. A possible role of genetic factors and serum magnesium needs to be further explored.

  17. Influence of a prenatal stressor on ACTH-induced cortisol secretion in yearling Brahman heifers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to test whether prenatal stress affects postnatal adrenocortical responsiveness to exogenous adrenocorticotropin-releasing hormone (ACTH) in calves of Brahman cows transported for 2-hour periods at 60, 80, 100, 120, and 140 days of gestation. Prenatally stressed yearl...

  18. The cortisol response to ACTH in pigs, heritability and influence of corticosteroid-binding globulin.

    PubMed

    Larzul, C; Terenina, E; Foury, A; Billon, Y; Louveau, I; Merlot, E; Mormede, P

    2015-12-01

    In the search for biological basis of robustness, this study aimed (i) at the determination of the heritability of the cortisol response to ACTH in juvenile pigs, using restricted maximum likelihood methodology applied to a multiple trait animal model, and (ii) at the study of the relationships between basal and stimulated cortisol levels with corticosteroid-binding globulin (CBG), IGF-I and haptoglobin, all important players in glucose metabolism and production traits. At 6 weeks of age, 298 intact male and female piglets from 30 litters (30 dams and 30 boars) were injected with 250 µg ACTH(1-24) (Synacthen). Blood was taken before ACTH injection to measure basal levels of cortisol, glucose, CBG, IGF-I and haptoglobin, and 60 min later to measure stimulated cortisol levels and glucose. Cortisol increased 2.8-fold after ACTH injection, with a high correlation between basal and stimulated levels (phenotypic correlation, r p=0.539; genetic correlation, r g=0.938). Post-ACTH cortisol levels were highly heritable (h 2=0.684) and could therefore be used for genetic selection of animals with a more reactive hypothalamic-pituitary-adrenocortical axis. CBG binding capacity correlated with cortisol levels measured in basal conditions in males only. No correlation was found between CBG binding capacity and post-ACTH cortisol levels. Basal IGF-I concentration was positively correlated with BW at birth and weaning, and showed a high correlation with CBG binding capacity with a strong sexual dimorphism, the correlation being much higher in males than in females. Basal haptoglobin concentrations were negatively correlated with CBG binding capacity and IGF-I concentrations. Complex relationships were also found between circulating glucose levels and these different variables that have been shown to be related to glucose resistance in humans. These data are therefore valuable for the genetic selection of animals to explore the consequences on production and robustness traits, but

  19. The cortisol response to ACTH in pigs, heritability and influence of corticosteroid-binding globulin.

    PubMed

    Larzul, C; Terenina, E; Foury, A; Billon, Y; Louveau, I; Merlot, E; Mormede, P

    2015-12-01

    In the search for biological basis of robustness, this study aimed (i) at the determination of the heritability of the cortisol response to ACTH in juvenile pigs, using restricted maximum likelihood methodology applied to a multiple trait animal model, and (ii) at the study of the relationships between basal and stimulated cortisol levels with corticosteroid-binding globulin (CBG), IGF-I and haptoglobin, all important players in glucose metabolism and production traits. At 6 weeks of age, 298 intact male and female piglets from 30 litters (30 dams and 30 boars) were injected with 250 µg ACTH(1-24) (Synacthen). Blood was taken before ACTH injection to measure basal levels of cortisol, glucose, CBG, IGF-I and haptoglobin, and 60 min later to measure stimulated cortisol levels and glucose. Cortisol increased 2.8-fold after ACTH injection, with a high correlation between basal and stimulated levels (phenotypic correlation, r p=0.539; genetic correlation, r g=0.938). Post-ACTH cortisol levels were highly heritable (h 2=0.684) and could therefore be used for genetic selection of animals with a more reactive hypothalamic-pituitary-adrenocortical axis. CBG binding capacity correlated with cortisol levels measured in basal conditions in males only. No correlation was found between CBG binding capacity and post-ACTH cortisol levels. Basal IGF-I concentration was positively correlated with BW at birth and weaning, and showed a high correlation with CBG binding capacity with a strong sexual dimorphism, the correlation being much higher in males than in females. Basal haptoglobin concentrations were negatively correlated with CBG binding capacity and IGF-I concentrations. Complex relationships were also found between circulating glucose levels and these different variables that have been shown to be related to glucose resistance in humans. These data are therefore valuable for the genetic selection of animals to explore the consequences on production and robustness traits, but

  20. Size reduction of an ACTH-secreting pituitary macroadenoma in Nelson's syndrome by sodium valproate: effect of withdrawal and re-institution of treatment.

    PubMed

    Loli, P; Berselli, M E; Vignati, F; De Grandi, C; Tagliaferri, M

    1988-11-01

    We describe herein the reduction in the size of an ACTH-secreting pituitary macroadenoma in a patient with Nelson's syndrome during chronic administration of sodium valproate, and the changes in tumour volume after withdrawal and re-institution of treatment. The patient had elevated plasma ACTH levels (1123-1255 pmol/l), which increased markedly after CRH stimulation. A first 4-month course of sodium valproate administration (600 mg/day, orally) was started. Plasma ACTH fell to 550-726 pmol/l with persistence of responsiveness to CRH; brain computed tomography showed a clearcut reduction of tumour size. One month after drug withdrawal, the tumour volume appeared unchanged and plasma ACTH values ranged between 374 and 440 pmol/l. One and a half year after drug withdrawal, a brain computed tomography showed re-expansion of the pituitary adenoma with evidence of suprasellar extension, which had never been seen previously. Plasma ACTH ranged between 113 and 199 pmol/l. A second course of sodium valproate was started; after three months, a brain computed tomography documented clearcut reduction of tumour volume from a suprasellar extension to a partially empty pituitary fossa. Plasma ACTH ranged from 396 to 542 pmol/l with persistence of responsiveness to CRH. The present report documents for the first time the reduction of tumour size in a patient with an ACTH-secreting macroadenoma by chronic administration of sodium valproate.

  1. Bilateral and simultaneous venous sampling of inferior petrosal sinuses for ACTH and PRL determination: preoperative localization of ACTH-secreting microadenomas.

    PubMed

    Vignati, F; Berselli, M E; Scialfa, G; Boccardi, E; Loli, P

    1989-04-01

    We report our experience on venous sampling of the inferior petrosal sinuses for basal and CRH-stimulated ACTH and PRL gradients in 8 patients with surgically proven Cushing's disease who had normal preoperative neuroradiological studies. In 7 patients basal plasma ACTH concentrations in the inferior petrosal sinus ipsilateral to the tumor were higher than in the contralateral sinus; the gradients were enhanced by oCRH administration. In one out of two patients who had previously undergone unsuccessful pituitary microsurgery, neither basal nor oCRH-induced ACTH increases led to correct localization of the microadenoma within the pituitary. In 4 out of 7 patients basal serum PRL concentrations in the inferior petrosal sinus ipsilateral to the tumor were higher than in the contralateral; only two out of 4 showed an increase in PRL levels after oCRH injection. Our study confirms that simultaneous and bilateral venous sampling of inferior petrosal sinuses is a valuable means to identify the site of microadenomas in patients with Cushing's disease without neuroradiological evidence of the tumor. This procedure may give misleading results in patients previously operated on. Unilateral or predominant increases of PRL concentration during catheterization of the inferior petrosal sinuses, when present, always lateralize to the side of the corticotroph adenoma, providing a possible additional signal of the presence of the tumor.

  2. Is Prolactin Measurement of Value during Inferior Petrosal Sinus Sampling in Patients with ACTH-dependent Cushing’s Syndrome?

    PubMed Central

    Sharma, S. T.; Nieman, L. K.

    2014-01-01

    Inferior petrosal sinus sampling (IPSS) is considered the gold standard test to distinguish between Cushing’s disease (CD) and ectopic ACTH syndrome (EAS). Anomalous venous drainage, abnormal venous anatomy and lack of expertise can lead to false-negative IPSS results and thereby misclassification of patients with ACTH-dependent Cushing’s syndrome. Prolactin measurement during IPSS can improve diagnostic accuracy and decrease false negative results. A baseline prolactin inferior petrosal sinus to peripheral (IPS/P) ratio (ipsilateral to the dominant post-CRH ACTH IPS/P ratio) of 1.8 or more suggests successful catheterization during IPSS. Prolactin-normalized ACTH IPS/P ratios can then be used to differentiate between a pituitary and ectopic source of ACTH. Values ≤ 0.7 are suggestive of EAS and those ≥ 1.3 are indicative of CD but the implication of values between 0.7 and 1.3 remains unclear and needs further investigation. Larger prospective studies are also needed for further evaluation of the role of contralateral prolactin IPS/P ratios, post-CRH prolactin values and prolactin-adjusted ACTH inter-sinus ratios for tumor localization in CD. PMID:23887034

  3. Lack of ACTH lowering effect of sodium valproate in patients with ACTH hypersecretion.

    PubMed

    Loli, P; Berselli, M E; Frascatani, F; Muratori, F; Tagliaferri, M

    1984-04-01

    The effect of an oral dose of 200 or 400 mg sodium valproate (DPA) on ACTH and cortisol secretion was assessed in 11 patients with Cushing's disease (3 bilaterally adrenalectomized), 3 patients with Nelson's syndrome and 6 patients with Addison's disease. In none of the patients examined DPA induced changes in ACTH (and cortisol) levels appreciably different from the fluctuations recorded after placebo administration. The effect of a long term administration of sodium valproate (600-1000 mg/day) was evaluated in 2 patients with active Cushing's disease and in 1 patient with Nelson's syndrome (3 weeks, 3, 9 months respectively); in the 2 patients with Cushing's disease ACTH and cortisol secretion, 17-hydroxy-corticosteroids (17-OHCS) urinary excretion did not change during DPA treatment. Similarly the cortisol response to hypoglycemia and the 17-OHCS urinary excretion after dexamethasone were not normalized. Long term DPA administration did not induce either clinical or hormonal modifications in the patient with Nelson's syndrome. These findings do not support the possibility that a deficiency of a GABAergic system plays a role in the pathogenesis of ACTH hypersecretion. DPA does not seem to be of therapeutical value in the medical management of Cushing's disease and Nelson's syndrome.

  4. Analysis of the brain ACTH-immunoreactive peptide spectrum in inbred mice

    SciTech Connect

    Fedoseev, Yu.L.; Blednov, Yu.A.; Seredenin, S.B.

    1987-01-01

    Mice of the BALB/c (C) and C57BL/6 (B6) strains, characterized by high and low emotionality respectively in open field tests, have been shown to differ considerably in both the initial level and the time course of changes in the plasma ACTH concentration after exposure to stress in an open field and after administration of a benzodiazepine tranquilizer. The ACTH concentration in the pituitary gland of animals of these lines also differs. The ACTH molecule is known to contain regions with neurotropic activity. It can therefore be postulated that differences in the level of this hormone and the products of its bioconversion in the brain are an essential factor in the mechanisms of formation of the hereditary features of emotional behavior. In this first stage of this investigation, represented in this paper and undertaken to test this hypothesis, spectra of ACTH-immunoreactive peptides were studied in chromatographic fractions of an acid brain extract as well as in the blood plasma of mice belonging to B6 and C lines and their hybrids. The peptides were determined by radioimmunoassay.

  5. Adrenocorticotropin (ACTH) and corticosterone secretion by perifused pituitary and adrenal glands from rodents exposed to 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD).

    PubMed

    Pitt, J A; Buckalew, A R; House, D E; Abbott, B D

    2000-10-26

    Although in utero maternal stress has been shown to have lasting effects on rodent offspring, fetal effects of chemically-induced alterations of the maternal hypothalamic-pituitary-adrenal axis (HPA) have not been well studied. This study examined the effects of in vivo 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure on pituitary-adrenal function in the male rat, pregnant female rat and pregnant female mouse. The secretion of adrenocorticotropin (ACTH) and corticosterone (CORT) in pituitary and adrenal glands, respectively, was assessed in ex vivo perifusion cultures. Male and pregnant female (gestation day 8) Sprague-Dawley rats were gavaged once with 10 microgram/kg TCDD, pregnant female mice once with 24 microgram/kg TCDD, and euthanized 10 days later. Hemi-pituitary (rat) or whole anterior pituitaries (mice) and right adrenal glands from the same animal were quartered, perifused under baseline and stimulated conditions. In both males and pregnant females, TCDD did not affect corticotropin releasing hormone (CRH)-stimulated ACTH secretion. Neither total pituitary ACTH nor plasma ACTH was altered in either sex or species by TCDD treatment. ACTH-stimulated CORT secretion was not affected by TCDD in either sex or species, and adrenal tissue and plasma CORT levels were unchanged in males and pregnant females by TCDD. However, the plasma ACTH:CORT ratio was decreased about 46% in male rats treated with TCDD. Plasma CORT levels were 23-fold higher and plasma ACTH levels were 1.5-fold higher in pregnant females than in male rats. In male versus female rats, adrenal CORT and anterior pituitary ACTH tissue levels were about 7.5- and 1.75-fold higher and ACTH, respectively. Female mouse adrenal tissue CORT was about 4-fold greater than female rat. The reduced plasma ACTH:CORT ratio in the male rat suggests that TCDD disturbs HPA function. Exposure of male rat to a 5-fold higher dose in earlier studies clearly demonstrated effects of TCDD on male rat HPA. The present

  6. GIP-dependent adrenal Cushing's syndrome with incomplete suppression of ACTH.

    PubMed

    Croughs, R J; Zelissen, P M; van Vroonhoven, T J; Hofland, L J; N'Diaye, N; Lacroix, A; de Herder, W W

    2000-02-01

    ACTH-independent Cushing's syndrome may be due to the development of ectopic hormone receptors in adrenal tissue. Thus, in food-dependent Cushing's syndrome the adrenals aberrantly express receptors for gastric inhibitory polypeptide (GIP). We present the case of a 60-year-old woman with food-dependent Cushing's syndrome whose cortisol levels increased after stimulation with CRH. In this patient with Cushing's syndrome the finding of low basal plasma cortisol levels in the late night and early morning as well as a paradoxical rise of plasma cortisol during a 7-h infusion with dexamethasone (carried out without any restriction in food intake), suggested that cortisol production was stimulated at times of food intake. Hourly measurements of plasma cortisol for 48 h revealed prominent meal-related peaks. A plasma cortisol response, elicited by oral glucose administration, could be prevented by octreotide. Plasma ACTH was low or undetectable. CRH administration was followed by a ACTH response from 3 to 16 ng/l and a plasma cortisol response from 230 to 680 nmol/l. Octreotide treatment for nearly five months induced a partial clinical and biochemical remission. Total bilateral adrenalectomy was performed. The left adrenal was grossly enlarged (7 x 5.5 x 4 cm) and the right adrenal was slightly enlarged (6 x 4 x 1.8 cm). Microscopy revealed bilateral nodular hyperplasia. Cell suspensions of adrenal tissue from the patient did respond in a dose-dependent fashion to stimulation with GIP and were very sensitive to stimulation with synthetic ACTH1-24. However, CRH had no significant effect on cortisol production in vitro. Using RT-PCR amplification and cDNA hybridization, GIP receptor was found to be overexpressed in the left and right adrenal tissues from this patient as compared to adrenal tissues from a normal individual or from non GIP-dependent adrenal Cushing's syndrome. There was no evidence of presence of adrenal CRH receptors. Thus, in this patient with food

  7. Muscle transcriptome response to ACTH administration in a free-ranging marine mammal

    PubMed Central

    Champagne, Cory D.; Preeyanon, Likit; Ortiz, Rudy M.; Crocker, Daniel E.

    2015-01-01

    While much of our understanding of stress physiology is derived from biomedical studies, little is known about the downstream molecular consequences of adaptive stress responses in free-living animals. We examined molecular effectors of the stress hormones cortisol and aldosterone in the northern elephant seal, a free-ranging study system in which extreme physiological challenges and cortisol fluctuations are a routine part of life history. We stimulated the neuroendocrine stress axis by administering exogenous adrenocorticotropic hormone (ACTH) and examined the resultant effects by measuring corticosteroid hormones, metabolites, and gene expression before, during, and following administration. ACTH induced an elevation in cortisol, aldosterone, glucose, and fatty acids within 2 h, with complete recovery observed within 24 h of administration. The global transcriptional response of elephant seal muscle tissue to ACTH was evaluated by transcriptomics and involved upregulation of a highly coordinated network of conserved glucocorticoid (GC) target genes predicted to promote metabolic substrate availability without causing deleterious effects seen in laboratory animals. Transcriptional recovery from ACTH was characterized by downregulation of GC target genes and restoration of cell proliferation, metabolism, and tissue maintenance pathways within 24 h. Differentially expressed genes included several adipokines not previously described in muscle, reflecting unique metabolic physiology in fasting-adapted animals. This study represents one of the first transcriptome analyses of cellular responses to hypothalamic-pituitary-adrenal axis stimulation in a free-living marine mammal and suggests that compensatory, tissue-sparing mechanisms may enable marine mammals to maintain cortisol and aldosterone sensitivity while avoiding deleterious long-term consequences of stress. PMID:26038394

  8. Muscle transcriptome response to ACTH administration in a free-ranging marine mammal.

    PubMed

    Khudyakov, Jane I; Champagne, Cory D; Preeyanon, Likit; Ortiz, Rudy M; Crocker, Daniel E

    2015-08-01

    While much of our understanding of stress physiology is derived from biomedical studies, little is known about the downstream molecular consequences of adaptive stress responses in free-living animals. We examined molecular effectors of the stress hormones cortisol and aldosterone in the northern elephant seal, a free-ranging study system in which extreme physiological challenges and cortisol fluctuations are a routine part of life history. We stimulated the neuroendocrine stress axis by administering exogenous adrenocorticotropic hormone (ACTH) and examined the resultant effects by measuring corticosteroid hormones, metabolites, and gene expression before, during, and following administration. ACTH induced an elevation in cortisol, aldosterone, glucose, and fatty acids within 2 h, with complete recovery observed within 24 h of administration. The global transcriptional response of elephant seal muscle tissue to ACTH was evaluated by transcriptomics and involved upregulation of a highly coordinated network of conserved glucocorticoid (GC) target genes predicted to promote metabolic substrate availability without causing deleterious effects seen in laboratory animals. Transcriptional recovery from ACTH was characterized by downregulation of GC target genes and restoration of cell proliferation, metabolism, and tissue maintenance pathways within 24 h. Differentially expressed genes included several adipokines not previously described in muscle, reflecting unique metabolic physiology in fasting-adapted animals. This study represents one of the first transcriptome analyses of cellular responses to hypothalamic-pituitary-adrenal axis stimulation in a free-living marine mammal and suggests that compensatory, tissue-sparing mechanisms may enable marine mammals to maintain cortisol and aldosterone sensitivity while avoiding deleterious long-term consequences of stress. PMID:26038394

  9. Comparisons of synthetic 1-18 ACTH (Organon 2001) and 1-39 ACTH of animal origin in human subjects.

    PubMed

    Danowski, T S; Fisher, E R; Robinson, S M

    The studies in human subjects herein reported provide data on the relative effects of 1-18 ACTH (Organon 2001) and commercial 1-39 ACTH of animal origin on plasma cortisol, serum non-esterified fatty acids, and certain urinary steroids.

  10. Comparisons of synthetic 1-18 ACTH (Organon 2001) and 1-39 ACTH of animal origin in human subjects.

    PubMed

    Danowski, T S; Fisher, E R; Robinson, S M

    1976-01-01

    The studies in human subjects herein reported provide data on the relative effects of 1-18 ACTH (Organon 2001) and commercial 1-39 ACTH of animal origin on plasma cortisol, serum non-esterified fatty acids, and certain urinary steroids.

  11. Evaluation of the attention network test using vibrotactile stimulations.

    PubMed

    Salzer, Yael; Oron-Gilad, Tal; Henik, Avishai

    2015-06-01

    We report a vibrotactile version of the attention network test (ANT)-the tactile ANT (T-ANT). It has been questioned whether attentional components are modality specific or not. The T-ANT explores alertness, orienting, cognitive control, and their relationships, similar to its visual counterpart, in the tactile modality. The unique features of the T-ANT are in utilizing stimuli on a single plane-the torso-and replacing the original imperative flanker task with a tactile Simon task. Subjects wore a waist belt mounted with two vibrotactile stimulators situated on the back and positioned to the right and left of the spinal column. They responded by pressing keys with their right or left hand in reaction to the type of vibrotactile stimulation (pulsed/continuous signal). On a single trial, an alerting tone was followed by a short tactile (informative/noninformative) peripheral cue and an imperative tactile Simon task target. The T-ANT was compared with a variant of the ANT in which the flanker task was replaced with a visual Simon task. Experimental data showed effects of orienting over control only when the peripheral cues were informative. In contrast to the visual task, interactions between alertness and control or alertness and orienting were not found in the tactile task. A possible rationale for these results is discussed. The T-ANT allows examination of attentional processes among patients with tactile attentional deficits and patients with eyesight deficits who cannot take part in visual tasks. Technological advancement would enable implementation of the T-ANT in brain-imaging studies.

  12. Adrenocortical responses to ACTH in neonatal rats: effect of hypoxia from birth on corticosterone, StAR, and PBR.

    PubMed

    Raff, Hershel; Hong, Julie J; Oaks, Martin K; Widmaier, Eric P

    2003-01-01

    The adrenocortical response to hypoxia may be a critical component of the adaptation to this common neonatal stress. Little is known about adrenal function in vivo in hypoxic neonates. The purpose of this study was to evaluate adrenocortical responses to ACTH in suckling rat pups exposed to hypoxia from birth to 5-7 days of age compared with normoxic controls. We also evaluated potential cellular controllers of steroidogenic function in situ. In 7-day-old pups at 0800, hypoxia from birth resulted in increased basal (12.2 +/- 1.4 ng/ml; n = 12) and ACTH-stimulated (94.0 +/- 9.4 ng/ml; n = 14) corticosterone levels compared with normoxic controls (basal = 8.3 +/- 0.5 ng/ml; n = 11; stimulated = 51.3 +/- 3.8 ng/ml; n = 8). This augmentation occurred despite no significant difference in plasma ACTH levels in normoxic vs. hypoxic pups before (85 +/- 4 vs. 78 +/- 8 pg/ml) or after (481 +/- 73 vs. 498 +/- 52 pg/ml) porcine ACTH injection (20 microg/kg). This effect was similar in the afternoon at 6 days of age and even greater at 5 days of age at 0800. The aldosterone response to ACTH was not augmented by exposure to hypoxia from birth. Adrenocortical hypoxia-inducible factor (HIF)-1alpha mRNA was undetectable by RT-PCR. Steroidogenic acute regulatory (StAR) protein in adrenal subcapsules (zona fasciculata/reticularis) was augmented by exposure to hypoxia; this effect was greatest at 5 days of age. Peripheral-type benzodiazepine receptor (PBR) protein was also increased at 6 and 7 days of age in pups exposed to hypoxia from birth. We conclude that hypoxia from birth results in an augmentation of the corticosterone but not aldosterone response to ACTH. This effect appears to be mediated at least in part by an increase in controllers of mitochondrial cholesterol transport (StAR and PBR) and to occur independently of measurable changes in endogenous plasma ACTH. The augmentation of the corticosterone response to acute increases in ACTH in hypoxic pups is likely to be an

  13. Neuroendocrine ACTH-Producing Tumor of the Thymus—Experience with 12 Patients over 25 Years

    PubMed Central

    Neary, Nicola M.; Lopez-Chavez, Ariel; Abel, Brent S.; Boyce, Alison M.; Schaub, Nicholas; Kwong, King; Stratakis, Constantine A.; Moran, Cesar A.; Giaccone, Giuseppe

    2012-01-01

    Context: ACTH-producing neuroendocrine tumor (NET) of the thymus is a rare cause of Cushing's syndrome (CS). The literature consists mainly of isolated case reports. Patients: We studied 12 cases (eight males and four females) diagnosed between 1986 and 2010 with CS and thymic NET who underwent surgical resection. Main Outcome Measures: We measured time from onset of CS to diagnosis of thymic NET, tumor size, histological grade, time to recurrence, and survival and performed a meta-analysis of other published cases of CS associated with thymic NET. Results: Eleven of 12 patients presented with classic features of CS at a median age of 21 yr (range, 7–51). Four were children. The 24-h urine free cortisol was greater than 16-fold of normal, and biochemical testing was consistent with ectopic ACTH production in all 11. Another patient presenting with pulmonary embolus had a thymic mass and was later diagnosed with CS. All patients underwent thymectomy, and nine of 10 tumors exhibited positive ACTH immunochemistry. Median tumor diameter was 5 cm (range, 1–11.5). Six patients recurred 20–28 months after surgery with metastases to mediastinal lymph nodes (n = 5), bone (n = 5), liver (n = 1), parotid gland (n = 1), and breast (n = 1). Four of five patients treated with radiation therapy also received chemotherapy. All recurrent patients received ketoconazole; four later underwent bilateral adrenalectomy. Six recurrent patients died 22–90 months (median, 57) after thymectomy. At last review, six patients were alive 14–90 months (median, 49) after thymectomy. These data are similar to those from the meta-analysis. Conclusions: Thymic ACTH-producing NET is an aggressive disease that should be considered in CS with ectopic ACTH secretion, particularly in younger patients. PMID:22508705

  14. [Evaluation of the accuracy of inferior petrosal sinus sampling in the differential diagnosis of ACTH-dependent Cushing's syndrome].

    PubMed

    Tóth, Miklós; Vajda, Zsolt; Görömbey, Zoltán; Molnár, Ferenc; Major, László; Toke, Judit; Szabolcs, István; Szücs, Nikolette; Kovács, László; Kiss, Róbert; Czirják, Sándor; Füto, László; Gláz, Edit; Góth, Miklós; Rácz, Károly

    2007-05-01

    The differentiation of adrenocorticotropic hormone producing pituitary adenoma (Cushing's disease) from the ectopic ACTH syndrome is always a complex and difficult task, and in rare cases it is not possible to differentiate between the two disorders, even with the use of dynamic endocrine tests and the most advanced imaging techniques. Inferior petrosal sinus sampling (IPSS) with subsequent ACTH measurements became the gold-standard method of the differential diagnostic process. 34 patients with ACTH dependent Cushing's syndrome in whom the source of ACTH secretion couldn't be identified unambiguously with imaging techniques and/or dynamic endocrine tests underwent altogether 41 IPSS between 1999 and 2005. The sensitivity of the method was calculated on the basis of 31 samplings of 25 patients who had definite endocrinological diagnosis confirmed by the recovery from Cushing's syndrome after surgical intervention and/or by histological examinations (22 patients with ACTH-producing pituitary adenoma and 3 patients with ectopic ACTH syndrome). As a result of IPSS, pituitary-dependent Cushing's disease was diagnosed with a baseline central to peripheral ACTH ratio of >2.0 or with a ratio of >3.0 after corticotropin releasing hormone (CRH) administration. IPSS correctly identified ACTH-producing pituitary adenoma in 20 of 28 sampling procedures, with a sensitivity of 71.4%. Three patients had true negative and 8 had false negative results. There was no false positive result. Four of the 8 patients with false negative first sampling had a repeat sampling procedure leading to true positive result in each patient. In patients with Cushing's disease having true positive interventions, the basal and 5 minutes post-CRH ACTH concentrations were diagnostic in 14 and 19 cases, respectively. The sensitivity of IPSS within this series, reported for the first time from Hungary, was lower than it was found in much larger series published in international literature. In addition to

  15. Neonatal isolated ACTH deficiency (IAD): a potentially life-threatening but treatable cause of neonatal cholestasis

    PubMed Central

    Alsaleem, Mahdi; Saadeh, Lina; Misra, Amrit; Madani, Shailender

    2016-01-01

    Isolated ACTH deficiency (IAD) is a rare cause of neonatal cholestasis and hypoglycaemia. This diagnosis has a 20% mortality potential if unrecognised. We describe a case of an infant presenting with cholestatic jaundice and hypoglycaemia. The patient had laboratory findings suggestive of IAD, which was later confirmed with molecular genetic testing. One of the mutations this patient had is a new finding. The patient was started on glucocorticoid replacement therapy after which his bilirubin and glucose levels normalised. PMID:27535729

  16. Role of endotoxin and interleukin-1 in modulating ACTH, LH and sex steroid secretion.

    PubMed

    Rivier, C

    1990-01-01

    We have shown that the endotoxin LPS acted both at the level of the brain and the gonads to stimulate the hypothalamic-pituitary-adrenal, and inhibit the hypothalamic-pituitary-gonadal, axis. Exogenously administered IL-1 mimics most of the effects of LPS on pituitary activity. In addition, antibodies against IL-1 receptors can interfere with LPS-induced ACTH secretion. These results suggest that at least part of the ability of LPS to alter endocrine functions appears to depend upon endogenous interleukin-1.

  17. Surgical management of the ectopic ACTH syndrome.

    PubMed Central

    Davies, C J; Joplin, G F; Welbourn, R B

    1982-01-01

    Most patients with extra-pituitary ACTH-secreting tumors die from carcinoma, but a few can benefit from operation. Of 96 patients with Cushing's syndrome, 11 probably had such tumors. There were three modes of presentation: (1) three had malignant tumors with visceral metastases initially. One (bronchial carcinoid) died without operation. Two with carcinoma (thyroid medullary and islet-cell) underwent adrenalectomy with remission, but died soon. (2) three had apparently benign tumors initially. One (appendicular carcinoid) underwent appendectomy and one (bronchial carcinoid with hilar node metastases) underwent lobectomy. Both had rapid remissions. The third (pheochromocytoma) died after resection of the tumor. (3) five patients had no obvious tumors and underwent adrenalectomy with remission. In one a benign bronchial carcinoid was removed later. Four others remain well, but without localizing signs of tumor. The main biochemical features in all were hypokalemic alkalosis and very high urinary excretion of free cortisol. Seven of the eight patients without visceral metastases are in remission from one to 15 years after operation. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:6287949

  18. Hypokalaemia: common but not always benign. Severe, persistent hypokalaemia secondary to ectopic ACTH from a carcinoid tumour

    PubMed Central

    Mahmood, Muhammad Muzaffar; John, Kurien

    2012-01-01

    Hypokalaemia is a common and often benign observation. There is usually an obvious underlying cause for the anomaly. However, hypokalaemia can very rarely be the sole presentation of a more sinister disease. A high index of suspicion and a systematic approach are therefore required to avoid delays in the management, especially in the context of presentation to a medical team. We present a case of a patient with severe and persistent hypokalaemia due to ectopic adrenocorticotropic hormone (ACTH) secretion secondary to a carcinoid tumour. The case report is followed by a brief discussion on the approach to the management of hypokalaemia and additional tests to confirm ectopic ACTH. PMID:23152181

  19. Role of ACTH and Other Hormones in the Regulation of Aldosterone Production in Primary Aldosteronism.

    PubMed

    El Ghorayeb, Nada; Bourdeau, Isabelle; Lacroix, André

    2016-01-01

    The major physiological regulators of aldosterone production from the adrenal zona glomerulosa are potassium and angiotensin II; other acute regulators include adrenocorticotropic hormone (ACTH) and serotonin. Their interactions with G-protein coupled hormone receptors activate cAMP/PKA pathway thereby regulating intracellular calcium flux and CYP11B2 transcription, which is the specific steroidogenic enzyme of aldosterone synthesis. In primary aldosteronism (PA), the increased production of aldosterone and resultant relative hypervolemia inhibits the renin and angiotensin system; aldosterone secretion is mostly independent from the suppressed renin-angiotensin system, but is not autonomous, as it is regulated by a diversity of other ligands of various eutopic or ectopic receptors, in addition to activation of calcium flux resulting from mutations of various ion channels. Among the abnormalities in various hormone receptors, an overexpression of the melanocortin type 2 receptor (MC2R) could be responsible for aldosterone hypersecretion in aldosteronomas. An exaggerated increase in plasma aldosterone concentration (PAC) is found in patients with PA secondary either to unilateral aldosteronomas or bilateral adrenal hyperplasia (BAH) following acute ACTH administration compared to normal individuals. A diurnal increase in PAC in early morning and its suppression by dexamethasone confirms the increased role of endogenous ACTH as an important aldosterone secretagogue in PA. Screening using a combination of dexamethasone and fludrocortisone test reveals a higher prevalence of PA in hypertensive populations compared to the aldosterone to renin ratio. The variable level of MC2R overexpression in each aldosteronomas or in the adjacent zona glomerulosa hyperplasia may explain the inconsistent results of adrenal vein sampling between basal levels and post ACTH administration in the determination of source of aldosterone excess. In the rare cases of glucocorticoid remediable

  20. Role of ACTH and Other Hormones in the Regulation of Aldosterone Production in Primary Aldosteronism

    PubMed Central

    El Ghorayeb, Nada; Bourdeau, Isabelle; Lacroix, André

    2016-01-01

    The major physiological regulators of aldosterone production from the adrenal zona glomerulosa are potassium and angiotensin II; other acute regulators include adrenocorticotropic hormone (ACTH) and serotonin. Their interactions with G-protein coupled hormone receptors activate cAMP/PKA pathway thereby regulating intracellular calcium flux and CYP11B2 transcription, which is the specific steroidogenic enzyme of aldosterone synthesis. In primary aldosteronism (PA), the increased production of aldosterone and resultant relative hypervolemia inhibits the renin and angiotensin system; aldosterone secretion is mostly independent from the suppressed renin–angiotensin system, but is not autonomous, as it is regulated by a diversity of other ligands of various eutopic or ectopic receptors, in addition to activation of calcium flux resulting from mutations of various ion channels. Among the abnormalities in various hormone receptors, an overexpression of the melanocortin type 2 receptor (MC2R) could be responsible for aldosterone hypersecretion in aldosteronomas. An exaggerated increase in plasma aldosterone concentration (PAC) is found in patients with PA secondary either to unilateral aldosteronomas or bilateral adrenal hyperplasia (BAH) following acute ACTH administration compared to normal individuals. A diurnal increase in PAC in early morning and its suppression by dexamethasone confirms the increased role of endogenous ACTH as an important aldosterone secretagogue in PA. Screening using a combination of dexamethasone and fludrocortisone test reveals a higher prevalence of PA in hypertensive populations compared to the aldosterone to renin ratio. The variable level of MC2R overexpression in each aldosteronomas or in the adjacent zona glomerulosa hyperplasia may explain the inconsistent results of adrenal vein sampling between basal levels and post ACTH administration in the determination of source of aldosterone excess. In the rare cases of glucocorticoid remediable

  1. Effect of adrenocorticotropic hormone (ACTH) and insulin on the phagocytic capacity of Tetrahymena.

    PubMed

    Köhidai, L; Lovas, B; Csaba, G

    1995-06-01

    Adrenocorticotropic hormone (ACTH) and insulin negatively influenced the phagocytic activity of Tetrahymena. The two hormones had diverse effects after 4 hr of treatments on no-test-particle containing, "0-cells". At this time the number of "0 cells" was significantly lower in the ACTH-treated groups, while in the insulin-treated groups there was an increase of "0-cells" compared to the control and to the results of the starting experiment. Considering previous results, when small molecular weight hormones, if did at all, positively influenced phagocytosis in Tetrahymena, the experiments call the attention to the differences caused by the size of the signal molecules. In the light of the literary data on hormone effects to phagocytosis in mammals and men, the similarity of the effects in species being very far from each other in evolution, could be concluded.

  2. Effectiveness of abstinence-based incentives: interaction with intake stimulant test results.

    PubMed

    Stitzer, Maxine L; Petry, Nancy; Peirce, Jessica; Kirby, Kimberly; Killeen, Therese; Roll, John; Hamilton, John; Stabile, Patricia Q; Sterling, Robert; Brown, Chanda; Kolodner, Ken; Li, Rui

    2007-10-01

    Intake urinalysis test result (drug positive vs. negative) has been previously identified as a strong predictor of drug abuse treatment outcome, but there is little information about how this prognostic factor may interact with the type of treatment delivered. The authors used data from a multisite study of abstinence incentives for stimulant abusers enrolled in outpatient counseling treatment (N. M. Petry, J. M. Peirce, et al., 2005) to examine this question. The first study urine was used to stratify participants into stimulant negative (n = 306) versus positive (n = 108) subgroups. Abstinence incentives significantly improved retention in those testing negative but not in those testing positive. Findings suggest that stimulant abusers presenting to treatment with a stimulant-negative urine benefit from abstinence incentives, but alternative treatment approaches are needed for those who test stimulant positive at intake.

  3. Effectiveness of abstinence-based incentives: interaction with intake stimulant test results.

    PubMed

    Stitzer, Maxine L; Petry, Nancy; Peirce, Jessica; Kirby, Kimberly; Killeen, Therese; Roll, John; Hamilton, John; Stabile, Patricia Q; Sterling, Robert; Brown, Chanda; Kolodner, Ken; Li, Rui

    2007-10-01

    Intake urinalysis test result (drug positive vs. negative) has been previously identified as a strong predictor of drug abuse treatment outcome, but there is little information about how this prognostic factor may interact with the type of treatment delivered. The authors used data from a multisite study of abstinence incentives for stimulant abusers enrolled in outpatient counseling treatment (N. M. Petry, J. M. Peirce, et al., 2005) to examine this question. The first study urine was used to stratify participants into stimulant negative (n = 306) versus positive (n = 108) subgroups. Abstinence incentives significantly improved retention in those testing negative but not in those testing positive. Findings suggest that stimulant abusers presenting to treatment with a stimulant-negative urine benefit from abstinence incentives, but alternative treatment approaches are needed for those who test stimulant positive at intake. PMID:17907862

  4. Responses of calves to injections of ACTH and their relationship with growth rate.

    PubMed

    Ramin, A G; Daniel, R C; Fenwick, D C; Verrall, R G

    1995-07-01

    A study was made of the effects of exogenous adrenocorticotropin (ACTH) on the levels of blood components in 109 dairy replacement calves and the statistical correlations between these effects and the growth rates of the calves from birth to six months. Blood samples were taken from a jugular vein before ACTH was injected and then at two, four, six and eight hours afterwards, and analysed for plasma cortisol concentration, total white cell counts, packed cell volume, haemoglobin, plasma glucose, sodium, potassium, magnesium and inorganic phosphorus, erythrocyte sodium, potassium and magnesium, serum ionised calcium and total protein and total plasma calcium concentration. The injection of 1.1 +/- 0.02 iu/kg of ACTH intramuscularly resulted in a peak plasma cortisol concentration after two hours which had not returned to normal after eight hours. It also resulted in leucocytosis, lymphopenia, neutrophilia, eosinopenia and hypophosphataemia; the mean changes were repeatable (P < 0.05) in 49 of the calves tested two months later. The weight gains to six months of age could be predicted from the degree of the changes in several blood constituents. Significant partial regression coefficients were found for the change in glucose concentration (0 to four hours), absolute neutrophil count (0 to two hours), absolute lymphocyte count (0 to four hours) and loge absolute eosinophil count (0 to two hours). The multiple regression sum of squares was highly significant (P < 0.0001), and the multiple coefficient of determination was 0.305. It was concluded that the changes in these blood components after an injection of ACTH might be used to predict the weight gains of dairy replacement calves.

  5. Laboratory Evaluation of EGS Shear Stimulation-Test 001

    DOE Data Explorer

    Bauer, Steve

    2014-07-29

    this is the results of an initial setup-shakedon test in order to develop the plumbing system for this test design. a cylinder of granite with offset holes was jacketed and subjected to confining pressure and low temperature (85C) and pore water pressure. flow through the sample was developed at different test stages.

  6. EXPERIENCE WITH CORTISONE AND ACTH IN A PRIVATE CLINIC

    PubMed Central

    Krupp, Marcus A.; Saier, Milton; Keddie, Frances; Tanner, Ralph; Snell, A. M.

    1951-01-01

    Cortisone and ACTH are valuable agents for treating a large variety of diseases. In appropriate situations they may save life. It may be possible to prevent loss of vision in eye disease or permanent damage to important viscera in generalized disease. With ready access to these agents through the pharmacist, it is important to know that cortisone and ACTH can be used in office practice provided patients are selected carefully and followed frequently and closely. Strict observation of criteria for selection of patients limited the size of the series of patients reported upon, but by the same token the incidence of complications from therapy was exceptionally small. Every physician who elects to employ these potent hormones must become familiar with their physiological effects and with the various methods of exhibiting them. Some of these effects are noted in this paper, but the experiences reviewed here provide an incomplete picture of the wide application of cortisone and ACTH. PMID:14848715

  7. ACTH producing pulmonary carcinoid and pituitary macroadenoma: a fortuitous association?

    PubMed

    Wong, M; Isa, S H Md; Kamaruddin, N A; Khalid, B A K

    2007-06-01

    We report a case of a 45 year-old man who presented initially with a non-functioning pituitary macroadenoma. A routine chest radiography done preoperatively revealed a right lung nodule which was confirmed by computed tomography (CT) of the thorax. Transfrontal hypophysectomy was performed while a conservative approach was taken for the lung nodule. Four years later, he presented acutely with adrenocorticotrophic hormone (ACTH) dependent Cushing's syndrome which resolved following a right lobectomy. Histological examination revealed an atypical carcinoid. To our knowledge, this is the first reported case of an ectopic ACTH secreting pulmonary carcinoid found in association with a non-functioning pituitary macroadenoma.

  8. The effect of ACTH upon faecal glucocorticoid excretion in the koala.

    PubMed

    Davies, Nicole; Gillett, Amber; McAlpine, Clive; Seabrook, Leonie; Baxter, Greg; Lunney, Daniel; Bradley, Adrian

    2013-10-01

    Environmental changes result in physiological responses of organisms, which can adversely affect population dynamics and reduce resistance to disease. These changes are expressed in chronic levels of stress. The measurement of glucocorticoid (GC) concentrations in faeces is a non-invasive method for monitoring stress in wildlife. The metabolism and excretion of steroids differ significantly between species and, as a consequence, non-invasive methods must be physiologically validated for each species. Koalas (Phascolarctos cinereus) are declining in numbers through much of their range. The role of chronic stress in koala populations has not been identified. Prior to the assessment of faecal GC concentrations in wild koala populations, the excretion timing and concentrations of GCs need to be determined. In this study, we assessed a method for identifying and measuring the concentrations of GC metabolites in faecal pellets of captive koalas following ACTH treatment. The results show that an elevation of plasma cortisol concentrations, using sustained release of ACTH, results in elevated concentrations of faecal cortisol/cortisol metabolites. Taking into account the excretion time lag, an increase in faecal cortisol metabolite concentrations corresponds to the release of GCs from the adrenal cortex as early as 36 h before faecal pellet collection. The calculations of steroid partitioning of plasma cortisol showed that the ACTH-stimulated values were significantly different from the control values for the concentrations of free, corticosteroid-binding globulin-bound and albumin-bound cortisol. This study validates the use of faecal cortisol analysis to assess the activity of the hypothalamo-pituitary-adrenocortical axis in freshly collected koala faecal pellets and indicates that the method should be suitable to assess the adrenocortical status of koalas in wild populations.

  9. Miniature wireless recording and stimulation system for rodent behavioural testing

    NASA Astrophysics Data System (ADS)

    Pinnell, R. C.; Dempster, J.; Pratt, J.

    2015-12-01

    Objective. Elucidation of neural activity underpinning rodent behaviour has traditionally been hampered by the use of tethered systems and human involvement. Furthermore the combination of deep-brain stimulation (DBS) and various neural recording modalities can lead to complex and time-consuming laboratory setups. For studies of this type, novel tools are required to drive forward this research. Approach. A miniature wireless system weighing 8.5 g (including battery) was developed for rodent use that combined multichannel DBS and local-field potential (LFP) recordings. Its performance was verified in a working memory task that involved 4-channel fronto-hippocampal LFP recording and bilateral constant-current fimbria-fornix DBS. The system was synchronised with video-tracking for extraction of LFP at discrete task phases, and DBS was activated intermittently at discrete phases of the task. Main results. In addition to having a fast set-up time, the system could reliably transmit continuous LFP at over 8 hours across 3-5 m distances. During the working memory task, LFP pertaining to discrete task phases was extracted and compared with well-known neural correlates of active exploratory behaviour in rodents. DBS could be wirelessly activated/deactivated at any part of the experiment during EEG recording and transmission, allowing for a seamless integration of this modality. Significance. The wireless system combines a small size with a level of robustness and versatility that can greatly simplify rodent behavioural experiments involving EEG recording and DBS. Designed for versatility and simplicity, the small size and low-cost of the system and its receiver allow for enhanced portability, fast experimental setup times, and pave the way for integration with more complex behaviour.

  10. Drug-induced suppression of ACTH secretion does not promote anti-depressive or anxiolytic effects.

    PubMed

    Ramos, Adriana de Toledo; Homem, Karen Silvia de Carvalho; Suchecki, Deborah; Tufik, Sergio; Troncone, Lanfranco Ranieri Paolo

    2014-05-15

    Mammals respond to a real or perceived stress in an integrated physiological and psychological fashion. Psychiatric disorders like major depression and anxiety have been associated to stressful events. In a previous study we demonstrated that the stress-induced ACTH secretion can be robustly inhibited by the concurrent use of CRF1 (CP154,526 - Pfizer) and V1B (SSR149415 - Sanofi-Aventis) non-peptide antagonists. A proof of mechanism was offered by substituting CP154,526 by SSR125543 and obtaining the same results on three stress models: forced swimming, ether vapor inhalation and restraint. SSR125543 effectively blocked only restraint stress-induced ACTH secretion. We then challenged the hypothesis that the concurrent use of both antagonists would have a potent effect on behavioral models of anxiety and depression. Decreasing doses (30-0.1 mg/kg s.c.) of both drugs were tested in three behavioral models: Porsolt forced swimming test, elevated plus maze and social interaction. Results showed that these drugs had no effect on anxiety models (plus maze and social interaction) but significantly reduced immobility time in the forced swimming test, suggesting anti-depressive action in a dose-range from 1 to 30 mg/kg, not different from the reported in the literature referring to one drug or the other. This negates the proposed hypothesis of summation/potentiation of effects as observed in stress-induced ACTH secretion. These results point toward the involvement of extra-hypothalamic sites for the anti-depressive effects. Recent Phase II clinical research on anti-depressive effects of these drugs has failed rising strong criticisms against the predictive value of behavioral tests currently employed. PMID:24569014

  11. Estimating adrenal cortical function in dogs with ACTH.

    PubMed

    Osbaldiston, G W; Greve, T

    1978-07-01

    The peripheral blood response to intramuscular injection of 10 units ACTH in dogs was investigated because no experimental evidence for the standardization of this procedure for clinical use was available. Following the injection of ACTH in sodium chloride solution, neutrophilia, monocytosis, eosinopenia, and lymphopenia occurred. With the exception of eosinopenia, the greatest change in the concentration of each cell type in peripheral blood occurred between 2 and 4 hours post injection. The maximum change in eosinophil numbers occurred between 4 and 6 hours post injection. When all cell types were considered, 4 hours post injection was the most suitable time to measure the cellular response in peripheral blood in dogs which respond to ACTH. The data indicate that change in the ratio of neutrophils to lymphocytes (N/L) prior to and at 2 to 4 hours after ACTH injection in normal dogs was a sensitive index of response and occured sooner than eosinopenia. The extent of change in the N/L ratio was such that accuracy in interpretation could be obtained by counting as few as 40 cells.

  12. Interferon-alpha stimulates the hypothalamic-pituitary-adrenal axis in vivo and in vitro.

    PubMed

    Gisslinger, H; Svoboda, T; Clodi, M; Gilly, B; Ludwig, H; Havelec, L; Luger, A

    1993-03-01

    The successful therapeutic use of interferon-alpha (IFN-alpha) in myeloproliferative disorders offered the possibility to test its acute and long-term effects on the hypothalamic-pituitary-adrenal (HPA) axis in humans. ACTH and cortisol plasma concentrations were measured in 8 patients hourly starting from 4 p.m. through 12 p.m. on three occasions. The first time all patients were studied before initiation of therapy, when the vehicle was injected alone. The patients were studied again on day 1 of IFN-alpha therapy (5 million units) and once more after 3 weeks of therapy. On the control day, plasma concentrations of ACTH and cortisol were in the range expected for this time of day. In contrast, after the first administration of IFN-alpha a significant stimulation of the HPA axis was observed. After 3 weeks of IFN-alpha therapy, no significant stimulation of the HPA axis occurred after administration of IFN-alpha. IFN-alpha-induced adaptive changes in the HPA axis were also indicated by a significantly enhanced ACTH and cortisol response to exogenously administered supramaximal doses of corticotropin-releasing hormone (CRH) when the patients had been on IFN-alpha treatment for 3 weeks. To determine the exact locus of the IFN-alpha action, in vitro experiments were performed using rat hypothalamic organ and primary pituitary and adrenal cell culture systems. Thereby a significant stimulation of hypothalamic CRH secretion and rat adrenal corticosterone production was observed after INF-alpha at concentrations of 5 x 10(-8) M or 10(-7) M respectively. In contrast, no direct IFN-alpha effect on pituitary ACTH secretion could be observed in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. The influence of aspirin on exercise-induced changes in adrenocorticotrophic hormone (ACTH), cortisol and aldosterone (ALD) concentrations.

    PubMed

    Przybyłowski, Jan; Obodyński, Kazimierz; Lewicki, Czesław; Kuźniar, Jerzy; Zaborniak, Stanisław; Drozd, Sławomir; Czarny, Wojciech; Garmulewicz, Maciej

    2003-04-01

    The influence of aspirin (ASA) on the endocrinology system and prostaglandin (PGs) synthesis is not completely clear. The aim of the study was to estimate the influence of ASA on the changes in the concentration of ACTH, cortisol and aldosterone (ALD) induced by physical exercise. This study was conducted on 19 healthy students (age 21-23 years). They were subjected to intensive physical exercise on a cycle ergometer. On the day prior to the experiment, 12 subjects took two 0.5-g doses of ASA in a wafer, and another 0.5 g 3-4 h before the test on the day of the investigation (ASA group). The remaining seven subjects (control group) received placebo. Hematocrit, lactate concentration and concentrations of ACTH, cortisol and ALD were determined before exercise, after exercise, and after 30 min of recovery, in a blood sample taken from a cubital vein. Before exercise, the degree of platelet aggregation in response to arachidonic acid was estimated, in order to confirm the correct allocation to the two groups. Aggregation should only occur in the ASA group. ASA and control groups exercised for 30.3 (3.1) min and 30.2 (1.6) min, respectively. Maximal heart rate and lactate concentration were similar in both groups, as were the basal concentrations of ACTH and cortisol; the ALD concentration seemed lower in the ASA group, but the difference was not significant (p<0.1). In both groups after exercise ACTH, cortisol and ALD concentrations were significantly increased, however when compared to the control group, the increase of ACTH in the ASA group was significantly higher, and ALD increase significantly lower. After recovery there was a significant decrease in ACTH concentration, whereas the concentrations of ALD and cortisol did not change. The concentrations of cortisol in both groups after exercise and recovery were similar. That is most likely because the ACTH concentrations in the ASA and control groups were sufficient for almost maximal cortisol secretion. It is

  14. Sensorimotor cortex ablation induces time-dependent response of ACTH cells in adult rats: behavioral, immunohistomorphometric and hormonal study.

    PubMed

    Lavrnja, Irena; Trifunovic, Svetlana; Ajdzanovic, Vladimir; Pekovic, Sanja; Bjelobaba, Ivana; Stojiljkovic, Mirjana; Milosevic, Verica

    2014-02-10

    Traumatic brain injury (TBI) represents a serious event with far reaching complications, including pituitary dysfunction. Pars distalis corticotropes (ACTH cells), that represent the active module of hypothalamo-pituitary-adrenocortical axis, seem to be affected as well. Since pituitary failure after TBI has been associated with neurobehavioral impairments the aim of this study was to evaluate the effects of TBI on recovery of motor functions, morphology and secretory activity of ACTH cells in the pituitary of adult rats. Wistar male rats, initially exposed to sensorimotor cortex ablation (SCA), were sacrificed at the 2nd, 7th, 14th and 30th days post-surgery (dps). A beam walking test was used to evaluate the recovery of motor functions. Pituitary glands and blood were collected for morphological and hormonal analyses. During the first two weeks post-injury increased recovery of locomotor function was detected, reaching almost the control value at day 30. SCA induces significant increase of pituitary weights compared to their time-matched controls. The volume of ACTH-immunopositive cells was reduced at the 7th dps, while at the 14th dps their volume was enlarged, in comparison to corresponding sham controls. Volume density of ACTH cells was increased only at 14th dps, while at day 30 this increase was insignificant. The plasma level of ACTH transiently increased after the injury. The most pronounced changes were observed at the 7th and 14th dps, and were followed by decrease toward control levels at the 30th dps. Thus, temporal changes in the hypothalamic-pituitary-adrenal axis after traumatic brain injury appear to correlate with the recovery process. PMID:24291385

  15. [The GnRH-TRH double stimulation test before and following surgical removal of uterine leiomyoma].

    PubMed

    Berkholz, A; Rudolf, K; Kunkel, S

    1990-01-01

    In seven patients with uterine leiomyomatosis investigated the function of hypothalamic-pituitary-ovarian axis has been with a GnRH-TRH-double stimulation test. The basal levels of estradiol, progesterone, LH, FSH and PRL as well as the pituitary reaction after the stimulation were determined. Three patients had a tendency to a basal hypergonadotropinemia and four patients to hypoprolactinemia. The pituitary reaction following the stimulation does not show any connection between leiomyoma and secretion pattern of the hypothalamic-pituitary-ovarian axis.

  16. Quantification and characterization of ACTH-related peptides produced by human peripheral blood mononuclear cells

    SciTech Connect

    Pepper, G.M.; Maimon, J.; Schneider, B.S. )

    1991-04-01

    The authors have used a sensitive radioimmunoassay to quantify and characterize PBMC-associated immunoreactive ACTH (ACTH-IR). Mean ACTH content of freshly isolated human PBMCs was 3.8 {plus minus} 0.72 pg (SEM) per 10(6) cells. During 3 days of incubation ACTH-IR in conditioned media of control PBMCs increased significantly, p less than 0.02. Gel filtration chromatography revealed a minor peak of ACTH-IR coeluting with ACTH (1-39) and a major peak coeluting with ACTH (11-24). Treatment with 15 nM CRH did not alter the amount of ACTH-IR secreted or its gel pattern. Synthetic ACTH (11-24), was radioiodinated and was used for binding experiments that demonstrated specific high- and low-affinity binding sites for ACTH (11-24) on a human T cell line. These results add support for a role of ACTH and related peptides in immune regulatory systems and suggest that cell-specific post-translational processing of PBMC may generate an expanding number of biologically active moieties.

  17. Effects of ACTH, epinephrine and Met-enkephalin on brain beta-endorphin-like immunoreactivity, and of ACTH, epinephrine, Met-enkephalin and naloxone on retention, in normal and in protein-malnourished rats.

    PubMed

    Perry, M L; Netto, C A; Izquierdo, I

    1990-01-01

    Rats raised and maintained on a normal-protein diet (25% protein) responded to the ip administration of ACTH-(1-24), epinephrine or Met-enkephalin with a decrease in hypothalamic beta-endorphin-like immunoreactivity, which is attributable to a release of this substance. This effect was not seen in rats raised and maintained on a low-protein diet (8% protein). In the normal animals, the pre-test administration of ACTH, epinephrine or Met-enkephalin and the post-training administration of naloxone enhanced retention-test performance of a step-down inhibitory avoidance task. These behavioral effects were absent in the protein-malnourished rats. Previous studies have shown that the behavioral effect of post-training naloxone is secondary to the release of brain beta-endorphin during training, and that the pre-test effect of the hormones is due to a release of brain beta-endorphin induced by the substances themselves. Since it is not likely that the differences were caused by hyperreactivity to the aversive stimuli employed, the suggested interpretation is that protein-malnourished rats present a dysfunction in the brain beta-endorphin system which renders it unresponsive not only to novel training experiences, but also to the pre-test retrieval enhancing effects of ACTH, epinephrine and Met-enkephalin.

  18. Diurnal ACTH and plasma cortisol variations in healthy dogs and in those with pituitary-dependent Cushing's syndrome before and after treatment with retinoic acid.

    PubMed

    Castillo, V A; Cabrera Blatter, M F; Gómez, N V; Sinatra, V; Gallelli, M F; Ghersevich, M C

    2009-04-01

    Daytime variations in ACTH and plasma cortisol were studied in healthy dogs and in dogs with pituitary-dependent hypercortisolism (PDH), before and after treatment with retinoic acid. In control dogs ACTH showed a higher concentration at 8.00 AM and between 2.00 and 6.00 PM, with the lowest concentration registered at 10.00 AM (p<0.05 vs. 8.00 AM and 2.00 PM and p<0.01 vs. 4.00 PM). Cortisol did not show significant differences. In dogs with PDH, ACTH was lower at 8.00 AM (ACTH: p<0.01 vs. 2.00 and 4.00 PM; and p<0.05 vs. 6.00 PM). The lowest cortisol concentration was registered at 8.00 AM and 8.00 PM and the highest at 4.00 PM (p<0.05 vs. 8.00 AM and p<0.01 vs. 8.00 PM). After treatment, the lowest ACTH concentration was registered at 10.00 AM (p<0.01 vs. 2.00 and 4.00 PM). To conclude, the adrenal is desensitized in PDH possibly showing negative in diagnostic tests.

  19. Expression of melanocortin receptors in human prostate cancer cell lines: MC2R activation by ACTH increases prostate cancer cell proliferation.

    PubMed

    Hafiz, Saly; Dennis, John C; Schwartz, Dean; Judd, Robert; Tao, Ya-Xiong; Khazal, Kamel; Akingbemi, Benson; Mo, Xiu-Lei; Abdel-Mageed, Asim B; Morrison, Edward; Mansour, Mahmoud

    2012-10-01

    The melanocortin receptors (MCRs 1-5) are G protein coupled-receptors (GPCRs) that regulate food intake, inflammation, skin pigmentation, sexual function and steroidogenesis. Their peptide ligands, the melanocortins, are α-, β- and γ-melanocyte-stimulating hormone and adrenocorticotropic hormone (ACTH) all of which are secreted from the anterior pituitary gland under hypothalamic control. MC2R binds ACTH but has no affinity for the other melanocortins and is, thereby, pharmacologically different from MCRs that bind those ligands. Evidence suggests that elevated GPCRs transactivate the androgen receptor (AR), the critical mediator of prostate cell growth, and consequently promote prostate cancer cell proliferation. It may be that reduced central melanocortin signaling is coincidental with reversal of prostate cancer cachexia, but no data are available on the expression of, or the role for, MCRs in prostate cancer. Here, we show that MCR (1-5) mRNAs are expressed in androgen-dependent LNCaP and androgen-independent PC3 and DU-145 human prostate cancer cell lines. Further, MC2R, the specific target of ACTH, is expressed in LNCaP, PC3 and DU-145 cells. Among the several synthetic MCR peptide ligands that we used, only ACTH promoted concentration-dependent cell proliferation in the three cell lines as shown by MTT cell proliferation assay. In LNCaP cells, the effect was additive with testosterone stimulation and was partially blunted with SHU9119, a non-selective MCR antagonist. In the same cells, ACTH induced cAMP production and increased AR nuclear labeling in immunocytochemical assays. Our observations suggest that MC2R is involved in prostate carcinogenesis and that targeting MC2R signaling may provide a novel avenue in prostate carcinoma treatment. PMID:22842514

  20. ACTH and beta-endorphin in transcendental meditation.

    PubMed

    Infante, J R; Peran, F; Martinez, M; Roldan, A; Poyatos, R; Ruiz, C; Samaniego, F; Garrido, F

    1998-06-01

    We have evaluated the effect of Transcendental Meditation (TM) on the hypothalamo-hypophyseal-adrenal axis diurnal rhythms through the determination of hormone levels. Blood samples were taken at 0900 hours. and at 2000 hours. These samples were taken from 18 healthy volunteers who regularly practice TM and from nine healthy non-meditators. Cortisol, beta-endorphin, and adrenocorticotropic hormone (ACTH) were measured at both hours. TM practitioners showed no diurnal rhythm for ACTH and for beta-endorphin (ACTH, pg/mL, mean +/- SE; 13.8+/-1.2 - 12.1+/-1.5/beta-endorphin, pg/mL; 14.4+/-1.5 - 17.2+/-1.9, at 0900 hours and 2000 hours, respectively), in contrast to control subjects, who showed normal diurnal rhythm for these hormones and for cortisol (ACTH, pg/mL; 19.4+/-1.9 - 11.9+/-2.2/beta-endorphin, pg/mL; 25.4+/-1.7 - 17.7+/-1.1/Cortisol, ng/mL; 201.4+/-13.2 - 71.3+/-6.5, at 0900-2000 hours, respectively, p < 0.01 in the three cases). Practitioners of TM with similar anxiety levels to those of the control group showed a different pattern in the daytime secretion of pituitary hormones. TM thus appears to have a significant effect on the neuroendocrine axis. Because cortisol levels had a normal pattern in the TM group, these results may be due to a change in feedback sensitivity caused by this mental technique.

  1. The effect of Hoe-427 (an ACTH sub 4-9 analog) on free-choice ethanol consumption in male and female rats

    SciTech Connect

    Krishnan, S.; Maickel, R.P. )

    1991-01-01

    Ethanol consummatory patterns of individual male and female rats and the effects of Hoe-427 (Ebiratide), and ACTH{sub 4-9} analog, thereon, were studied in a test system using 24 hour, two-bottle free choice consumption between 0.2% saccharin and 10% ethanol in 0.2% saccharin. Single, daily i.p. doses of either ACTH{sub 4-10} or its analog resulted in a significant reduction of daily ethanol consumption with no effects on saccharin consumption. After 4 days of treatment, male rats consistently exhibited a rebound increase in ethanol consumption; this effect was not seen in females. The daily ethanol consummatory patterns of the female animals seemed to exhibit a 4-6 day cyclic rhythymicity, suggesting an interaction with estrous cycles. These results support a role for ACTH{sub 4-10} in the initiation of ethanol consummatory behavior in rats and suggests the existence of sex differences in this phenomenon.

  2. The role of inferior petrosal sinus sampling in ACTH-dependent Cushing's syndrome: review and joint opinion statement by members of the Italian Society for Endocrinology, Italian Society for Neurosurgery, and Italian Society for Neuroradiology.

    PubMed

    Pecori Giraldi, Francesca; Cavallo, Luigi Maria; Tortora, Fabio; Pivonello, Rosario; Colao, Annamaria; Cappabianca, Paolo; Mantero, Franco

    2015-02-01

    In the management of adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome, inferior petrosal sinus sampling (IPSS) provides information for the endocrinologist, the neurosurgeon, and the neuroradiologist. To the endocrinologist who performs the etiological diagnosis, results of IPSS confirm or exclude the diagnosis of Cushing's disease with 80%-100% sensitivity and over 95% specificity. Baseline central-peripheral gradients have suboptimal accuracy, and stimulation with corticotropin-releasing hormone (CRH), possibly desmopressin, has to be performed. The rationale for the use of IPSS in this context depends on other diagnostic means, taking availability of CRH and reliability of dynamic testing and pituitary imaging into account. As regards the other specialists, the neuroradiologist may collate results of IPSS with findings at imaging, while IPSS may prove useful to the neurosurgeon to chart a surgical course. The present review illustrates the current standpoint of these 3 specialists on the role of IPSS. PMID:25639323

  3. The role of inferior petrosal sinus sampling in ACTH-dependent Cushing's syndrome: review and joint opinion statement by members of the Italian Society for Endocrinology, Italian Society for Neurosurgery, and Italian Society for Neuroradiology.

    PubMed

    Pecori Giraldi, Francesca; Cavallo, Luigi Maria; Tortora, Fabio; Pivonello, Rosario; Colao, Annamaria; Cappabianca, Paolo; Mantero, Franco

    2015-02-01

    In the management of adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome, inferior petrosal sinus sampling (IPSS) provides information for the endocrinologist, the neurosurgeon, and the neuroradiologist. To the endocrinologist who performs the etiological diagnosis, results of IPSS confirm or exclude the diagnosis of Cushing's disease with 80%-100% sensitivity and over 95% specificity. Baseline central-peripheral gradients have suboptimal accuracy, and stimulation with corticotropin-releasing hormone (CRH), possibly desmopressin, has to be performed. The rationale for the use of IPSS in this context depends on other diagnostic means, taking availability of CRH and reliability of dynamic testing and pituitary imaging into account. As regards the other specialists, the neuroradiologist may collate results of IPSS with findings at imaging, while IPSS may prove useful to the neurosurgeon to chart a surgical course. The present review illustrates the current standpoint of these 3 specialists on the role of IPSS.

  4. ACTH-like peptides increase pain sensitivity and antagonize opiate analgesia

    NASA Technical Reports Server (NTRS)

    Heybach, J. P.; Vernikos, J.

    1981-01-01

    The role of the pituitary and of ACTH in pain sensitivity was investigated in the rat. Pain sensitivity was assessed by measuring paw-lick and jump latencies in response to being placed on a grid at 55 C. Hypophysectomy reduced pain sensitivity, and this effect was reversed by the intracerebroventricular (ICV) injection of the opiate antagonist naloxone. Similarly, the analgesia produced by a dose of morphine was antagonized by the administration of ACTH or alpha-MSH. The peripheral injection of ACTH or alpha-MSH in normal rats did not increase pain sensitivity. However, ACTH administered ICV increased pain sensivity within 10 min. The results indicate that the pituitary is the source of an endogenous opiate antagonist and hyperalgesic factor and that this factor is ACTH or an ACTH-like peptide. This activity resides in the N-terminal portion of the ACTH molecule since ACTH sub 4-10 is not active in this respect, nor does this activity require a free N-terminal serine since alpha-MSH appears to be almost as potent as the ACTH sub 1-24 peptide. It is concluded that ACTH-like peptides of pituitary origin act as endogenous hyperalgesic and opiate antagonistic factors.

  5. Pre- and postnatally administered ACTH, Organon 2766 and CRF facilitate or inhibit active avoidance task performance in young adult mice.

    PubMed

    Honour, L C; White, M H

    1988-01-01

    This study investigated the effect of learning/memory-related neuropeptides on behavioral task performance in later life. A 1 mg/kg dosage of adrenocorticotropic hormone 4-9, Organon 2766, ACTH/MSH 4-10, ACTH 1-24, CRF, or diluent was subcutaneously injected into either pregnant females or into newborn pups during specific neural developmental windows. Each of the progeny was trained in an active-avoidance task and tested for acquisition on postpartum days 35-37. The mice were then tested for memory task performance and reacquisition on days 42-44 postpartum using the identical experimental paradigm as that used in the training sessions. Prenatal treatment with these memory-related neuropeptides resulted in significant facilitation of learning/memory task performance in male and female mice treated with Organon 2766 (p less than 0.001), and a significant inhibition of learning/memory task performance in males and females treated with ACTH 1-24 (p less than 0.01). Additional sex-specific performance facilitations and inhibitions resulted from the pre- or postnatal administration of the various neuropeptides used in this study. These results suggest that neuropeptides, when available in increased amounts during specific neural developmental windows, can significantly improve or suppress related behavioral performance capability in later life.

  6. Corticotropin (ACTH) regulates alternative RNA splicing in Y1 mouse adrenocortical tumor cells.

    PubMed

    Schimmer, Bernard P; Cordova, Martha

    2015-06-15

    The stimulatory effect of ACTH on gene expression is well documented and is thought to be a major mechanism by which ACTH maintains the functional and structural integrity of the gland. Previously, we showed that ACTH regulates the accumulation of over 1200 transcripts in Y1 adrenal cells, including a cluster with functions in alternative splicing of RNA. On this basis, we postulated that some of the effects of ACTH on the transcription landscape of Y1 cells are mediated by alternative splicing. In this study, we demonstrate that ACTH regulates the alternative splicing of four transcripts - Gnas, Cd151, Dab2 and Tia1. Inasmuch as alternative splicing potentially affects transcripts from more than two-thirds of the mouse genome, we suggest that these findings are representative of a genome-wide effect of ACTH that impacts on the mRNA and protein composition of the adrenal cortex.

  7. Screening test of stimulants in human urine utilizing headspace gas chromatography for field test.

    PubMed

    Tsuchihashi, H; Nakajima, K; Nishikawa, M; Suzuki, S; Oka, Y; Otsuki, K

    1990-03-01

    An accurate and simple screening method of stimulants in human urine using headspace gas chromatography utilizing heat of dissolution of potassium carbonate was developed. A 4.9-g portion of potassium carbonate was put into the vial prior to sending to the field, and a 5-ml aliquot of urine, suspected of containing stimulants and internal standard components was pipetted. After the vial was sealed and shaken by hand, 1 ml of its headspace gas was taken by disposable syringe and injected into the gas chromatograph. A compact gas chromatograph device with flame ionization detector and fused silica capillary column was developed for this experiment. Detection limits of methamphetamine and amphetamine were 1.0 micrograms/ml and 1.5 micrograms/ml, respectively. PMID:2335332

  8. Inhibitory effect of cyproheptadine on ACTH secretion in patients with Addison's disease.

    PubMed

    Loli, P; Frascatani, F; Gelli, D; Maggioni, M; Muratori, F; Ronzoni, M

    1983-01-01

    In 14 patients with Addison's disease plasma levels of ACTH were studied after administration of a single oral dose (16 mg) of cyproheptadine. The drug administration was followed by an inhibition of ACTH release. These results support the view that cyproheptadine may exert an inhibitory effect on ACTH secretion in subjects whose corticosteroid feedback mechanism is normal. We hypothesize that the effect of cyproheptadine might be related to its anti-serotonin or anti-histaminergic action.

  9. Floating light-activated microelectrical stimulators tested in the rat spinal cord

    NASA Astrophysics Data System (ADS)

    Abdo, Ammar; Sahin, Mesut; Freedman, David S.; Cevik, Elif; Spuhler, Philipp S.; Unlu, M. Selim

    2011-10-01

    Microelectrodes of neural stimulation utilize fine wires for electrical connections to driving electronics. Breakage of these wires and the neural tissue response due to their tethering forces are major problems encountered with long-term implantation of microelectrodes. The lifetime of an implant for neural stimulation can be substantially improved if the wire interconnects are eliminated. Thus, we proposed a floating light-activated microelectrical stimulator (FLAMES) for wireless neural stimulation. In this paradigm, a laser beam at near infrared (NIR) wavelengths will be used as a means of energy transfer to the device. In this study, microstimulators of various sizes were fabricated, with two cascaded GaAs p-i-n photodiodes, and tested in the rat spinal cord. A train of NIR pulses (0.2 ms, 50 Hz) was sent through the tissue to wirelessly activate the devices and generate the stimulus current. The forces elicited by intraspinal stimulation were measured from the ipsilateral forelimb with a force transducer. The largest forces were around 1.08 N, a significant level of force for the rat forelimb motor function. These in vivo tests suggest that the FLAMES can be used for intraspinal microstimulation even for the deepest implant locations in the rat spinal cord. The power required to generate a threshold arm movement was investigated as the laser source was moved away from the microstimulator. The results indicate that the photon density does not decrease substantially for horizontal displacements of the source that are in the same order as the beam radius. This gives confidence that the stimulation threshold may not be very sensitive to small displacement of the spinal cord relative to the spine-mounted optical power source.

  10. Floating light-activated microelectrical stimulators tested in the rat spinal cord.

    PubMed

    Abdo, Ammar; Sahin, Mesut; Freedman, David S; Cevik, Elif; Spuhler, Philipp S; Unlu, M Selim

    2011-10-01

    Microelectrodes of neural stimulation utilize fine wires for electrical connections to driving electronics. Breakage of these wires and the neural tissue response due to their tethering forces are major problems encountered with long-term implantation of microelectrodes. The lifetime of an implant for neural stimulation can be substantially improved if the wire interconnects are eliminated. Thus, we proposed a floating light-activated microelectrical stimulator (FLAMES) for wireless neural stimulation. In this paradigm, a laser beam at near infrared (NIR) wavelengths will be used as a means of energy transfer to the device. In this study, microstimulators of various sizes were fabricated, with two cascaded GaAs p-i-n photodiodes, and tested in the rat spinal cord. A train of NIR pulses (0.2 ms, 50 Hz) was sent through the tissue to wirelessly activate the devices and generate the stimulus current. The forces elicited by intraspinal stimulation were measured from the ipsilateral forelimb with a force transducer. The largest forces were around 1.08 N, a significant level of force for the rat forelimb motor function. These in vivo tests suggest that the FLAMES can be used for intraspinal microstimulation even for the deepest implant locations in the rat spinal cord. The power required to generate a threshold arm movement was investigated as the laser source was moved away from the microstimulator. The results indicate that the photon density does not decrease substantially for horizontal displacements of the source that are in the same order as the beam radius. This gives confidence that the stimulation threshold may not be very sensitive to small displacement of the spinal cord relative to the spine-mounted optical power source. PMID:21914931

  11. OVARIAN RESERVE TESTS AND THEIR UTILITY IN PREDICTING RESPONSE TO CONTROLLED OVARIAN STIMULATION IN RHESUS MONKEYS

    PubMed Central

    Wu, Julie M.; Takahashi, Diana L; Ingram, Donald K.; Mattison, Julie A.; Roth, George; Ottinger, Mary Ann; Zelinski, Mary B.

    2010-01-01

    Controlled ovarian stimulation (COS) is an alternative to natural breeding in nonhuman primates; however, these protocols are costly with no guarantee of success. Toward the objective of predicting COS outcome in rhesus monkeys, the current study evaluated three clinically used ovarian reserve tests (ORTs): day 3 (d3) follicle-stimulating hormone (FSH) with d3 inhibin B (INHB), the clomiphene citrate challenge test (CCCT), and the exogenous FSH Ovarian Reserve Test (EFORT). A COS was also performed and response was classified as either successful (COS+) or unsuccessful (COS−) and retrospectively compared to ORT predictions. FSH and INHB were assessed for best hormonal index in conjunction with the aforementioned tests. INHB was consistently more accurate than FSH in all ORTs used. Overall, a modified version of the CCCT using INHB values yielded the best percentage of correct predictions. This is the first report of ORT evaluation in rhesus monkeys and may provide a useful diagnostic test prior to costly follicle stimulations, as well as predicting the onset of menopause. PMID:20336797

  12. Naloxone inhibits and morphine potentiates. The adrenal steroidogenic response to ACTH

    NASA Technical Reports Server (NTRS)

    Heybach, J. P.; Vernikos, J.

    1980-01-01

    The adrenal actions were stereospecific since neither the positve stereoisomer of morphine, nor that of naloxone, had any effect on the adrenal response to exogenous adrenocorticotrophic hormone (ACTH). The administration of human beta endorphin to phyophysectomized rats had no effect on the adrenal corticosterone concentration nor did it alter the response of the adrenal gland to ACTH. These results indicate that morphine can potentiate the action of ACTH on the adrenal by a direct, stereospecific, dose dependent mechanism that is prevented by naloxone pretreatment and which may involve competition for ACTH receptors on the corticosterone secreting cells of the adrenal cortex.

  13. Increased corticosteroid binding capacity of plasma albumin but not of corticosteroid-binding globulin caused by ACTH-induced changes in free fatty acid concentrations in snowshoe hares and rabbits.

    PubMed

    Boonstra, R; Tinnikov, A A

    1998-01-01

    Free fatty acids (FFAs) are rapidly mobilized by ACTH and have been shown to be potent endogenous modulators of steroid-protein interactions. We increased FFA in lagomorphs by ACTH and then separated the transient increase in glucocorticoid binding capacity of plasma into that accounted for by changes in binding to albumin and to corticosteroid-binding globulin (CBG). Sequential injections of dexamethasone and ACTH into both snowshoe hares and laboratory rabbits resulted in the rapid mobilization of FFA only after the ACTH injection. The maximum corticosteroid binding capacity increase paralleled that of the FFA increase in both species. In rabbits, CBG levels remained constant over the duration of the experiment. Corticosterone binding by rabbit albumin increased in a dose-dependent fashion in response to increases in FFA (oleic and linoleic acid) concentrations. Finally, by stimulating FFA release in snowshoe hares with ACTH and separating the increase in corticosteroid binding capacity through selective denaturing of CBG by heat, we determined that the increase in plasma binding capacity was a response to changes in binding by albumin, not CBG. Thus FFA released in response to stressors in lagomorphs may effect short-term increases in steroid binding.

  14. Dexamethasone suppression test

    MedlinePlus

    DST; ACTH suppression test; Cortisol suppression test ... During this test, you will receive dexamethasone. This is a strong man-made (synthetic) glucocorticoid medication. Afterward, your blood is drawn ...

  15. Mapping the ‘Depression Switch’ During Intraoperative Testing of Subcallosal Cingulate Deep Brain Stimulation

    PubMed Central

    Choi, Ki Sueng; Riva-Posse, Patricio; Gross, Robert E.; Mayberg, Helen S.

    2016-01-01

    Importance The clinical utility of monitoring behavioral changes during intraoperative testing of acute subcallosal cingulate deep brain stimulation (DBS) is unknown. Objective To characterize structural connectivity correlates of DBS evoked behavioral effects using probabilistic tractography. Design Categorization of acute behavioral effects was conducted during DBS implantation surgery for treatment-resistant depression in a randomized and blinded testing session. Post-hoc analyses of the structural tractography patterns mediating distinct categories of evoked behavioral effects were defined. Setting Intra-operative testing during DBS surgery for depression at Emory University. Participants 9 adult participants with chronic treatment-resistant depression undergoing DBS surgery. Main Outcomes and Measures Categorization of stimulation-induced transient behavioral effects and delineation of the shared white matter tracts mediating response subtypes. Results Two stereotypical behavior patterns were identified: changes in interoceptive (noted changes in body state) and in exteroceptive awareness (shift in attention from patient to others). Structural connectivity showed that ‘best’ responses had a pattern of connections to bilateral ventromedial frontal cortex (via uncinate fasciculus and forceps minor) and cingulate cortex (via cingulum bundle) while ‘salient’ contacts had only cingulate involvement. Conclusions and Relevance This analysis of acute intraoperative behaviors in SCC DBS, and the subsequent identification of unique connectivity patterns may provide a potential biomarker to guide and optimize surgical implantation and to refine and optimize algorithms for selection of contacts in chronic stimulation PMID:26408865

  16. In vivo and in vitro characterization of antalarmin, a nonpeptide corticotropin-releasing hormone (CRH) receptor antagonist: suppression of pituitary ACTH release and peripheral inflammation.

    PubMed

    Webster, E L; Lewis, D B; Torpy, D J; Zachman, E K; Rice, K C; Chrousos, G P

    1996-12-01

    Corticotropin-releasing hormone (CRH) secreted from the hypothalamus is the major regulator of pituitary ACTH release and consequent glucocorticoid secretion. CRH secreted in the periphery also acts as a proinflammatory modulator. CRH receptors (CRH-R1, R2alpha, R2beta) exhibit a specific tissue distribution. Antalarmin, a novel pyrrolopyrimidine compound, displaced 12SI-oCRH binding in rat pituitary, frontal cortex and cerebellum, but not heart, consistent with antagonism at the CRHR1 receptor. In vivo antalarmnin (20 mg/kg body wt.) significantly inhibited CRH-stimulated ACTH release and carageenin-induced subcutaneous inflammation in rats. Antalarmin, or its analogs, hold therapeutic promise in disorders with putative CRH hypersecretion, such as melancholic depression and inflammatory disorders. PMID:8940412

  17. Transcranial Direct Current Stimulation of Frontal Cortex Decreases Performance on the WAIS-IV Intelligence Test

    PubMed Central

    Sellers, Kristin K.; Mellin, Juliann M.; Lustenberger, Caroline M.; Boyle, Michael R.; Lee, Won Hee; Peterchev, Angel V.; Frohlich, Flavio

    2015-01-01

    Transcranial direct current stimulation (tDCS) modulates excitability of motor cortex. However, there is conflicting evidence about the efficacy of this non-invasive brain stimulation modality to modulate performance on cognitive tasks. Previous work has tested the effect of tDCS on specific facets of cognition and executive processing. However, no randomized, double-blind, sham-controlled study has looked at the effects of tDCS on a comprehensive battery of cognitive processes. The objective of this study was to test if tDCS had an effect on performance on a comprehensive assay of cognitive processes, a standardized intelligence quotient (IQ) test. The study consisted of two substudies and followed a double-blind, between-subjects, sham-controlled design. In total, 41 healthy adult participants completed the Wechsler Adult Intelligence Scale, Fourth Edition (WAIS-IV) as a baseline measure. At least one week later, participants in substudy 1 received either bilateral tDCS (anodes over both F4 and F3, cathode over Cz, 2mA at each anode for 20 minutes) or active sham tDCS (2mA for 40 seconds), and participants in substudy 2 received either right or left tDCS (anode over either F4 or F3, cathode over Cz, 2mA for 20 minutes). In both studies, the WAIS-IV was immediately administered following stimulation to assess for performance differences induced by bilateral and unilateral tDCS. Compared to sham stimulation, right, left, and bilateral tDCS reduced improvement between sessions on Full Scale IQ and the Perceptual Reasoning Index. This demonstration that frontal tDCS selectively degraded improvement on specific metrics of the WAIS-IV raises important questions about the often proposed role of tDCS in cognitive enhancement. PMID:25934490

  18. Uptake and release of adrenal ascorbic acid in the guinea pig after injection of ACTH

    SciTech Connect

    Kipp, D.E.; Rivers, J.M.

    1987-09-01

    The effect of a single injection of ACTH (3 IU/100 g body weight) on the distribution of ascorbic acid (AA) and radiolabeled AA in 20 tissues was studied in adult male guinea pigs consuming 500 mg AA/kg diet. Saline- or ACTH-injected animals were simultaneously injected with (1-/sup 14/C)AA, and killed at 0.5, 1, 2, 4 and 6 h after injection. There was no significant difference between treatments in the weight of any tissue over the 6-h experimental period. As anticipated, the concentration of AA in the adrenals of animals injected with ACTH was 33% of that of animals injected with saline at 4 h. Unexpectedly, the concentration of radiolabeled AA in the adrenals at 0.5 h after ACTH injection was 172% of that after saline injection. The concentration of radiolabeled AA in the adrenal of the saline-injected animals increased slowly over time to reach a level similar to that of ACTH-injected animals by 6 h. There was no effect of ACTH on the level of AA or uptake in any of the other tissues examined. These results demonstrate that a single dose of ACTH markedly influences the retention of AA in the adrenal gland without similarly altering retention of AA in other tissues. Furthermore, ACTH treatment causes both accelerated uptake and release of AA into the adrenals.

  19. Reliability of Autonomic Responses and Malaise Across Multiple Motion Sickness Stimulation Tests

    NASA Technical Reports Server (NTRS)

    Stout, Cynthia S.; Toscano, William B.; Cowings, Patricia S.

    1993-01-01

    There is general agreement that a high degree of variability exists between subjects in their autonomic nervous system responses to motion sickness stimulation. Additionally, a paucity of data exists that examines the variability within an individual across repeated motion sickness tests. Investigators have also examined the relationship of autonomic responses to motion sickness development. These investigations have used analyses at discrete points in time to describe this relationship. This approach fails to address the time course of autonomic responses and malaise development throughout the motion sickness test. Our objectives were to examine the reliability of autonomic responses and malaise using the final minute of the motion sickness test across five testing occasions, to examine the reliability of the change in autonomic responses and the change in malaise across five testing occasions, and to examine the relationship between changes in autonomic responses and changes in malaise level across the entire motion sickness test. Our results indicate that, based on the final minute of testing, the autonomic responses of heart rate, blood volume pulse, and respiration rate are moderately stable across multiple tests. Changes in heart rate, blood volume pulse, respiration rate, and malaise throughout the test duration were less stable across the tests. We attribute this instability to variations in individual susceptibility and the error associated with estimating a measure of autonomic gain.

  20. The skin test antigen stimulated killer (STAK) cell mediating NK like CMC is OKM1 positive and OKT3 negative.

    PubMed Central

    Tartof, D; Curran, J J; Levitt, D; Loken, M R

    1983-01-01

    Recently we demonstrated that candida antigen stimulated natural killer cell like cell-mediated cytolysis (NK like CMC) in peripheral blood mononuclear cells (PBMNC) isolated from normal individuals (Tartof et al., 1980). Utilizing monoclonal antibodies directed against human mononuclear cell subpopulations in conjunction with a fluorescence activated cell sorter (FACS) we determined that, similar to the previously described NK cell, the skin test antigen stimulated killer (STAK) cell is a larger OKM1 positive, OKT3 negative cell. We obtained similar results using two different skin test antigens. Thus, stimulation of NK like CMC in PBMNC by skin test antigens probably represents activation of NK or NK like cells. PMID:6360439

  1. Pharmacodynamics of aqueous leuprolide acetate stimulation testing in girls: correlation between clinical diagnosis and time of peak luteinizing hormone level.

    PubMed

    Chi, Carolyn H; Durham, Eileen; Neely, E Kirk

    2012-10-01

    We assessed the pharmacodynamics of a 3-hour leuprolide stimulation test in 11 girls with precocious puberty to determine an optimal single sampling time. Luteinizing hormone level following leuprolide stimulation was near maximum by 30 minutes in girls with central precocious puberty, whereas it continued to rise slowly in girls with nonprogressive puberty.

  2. The adrenocortical response of greater sage grouse (Centrocercus urophasianus) to capture, ACTH injection, and confinement, as measured in fecal samples

    USGS Publications Warehouse

    Jankowski, M.D.; Wittwer, D.J.; Heisey, D.M.; Franson, J.C.; Hofmeister, E.K.

    2009-01-01

    Investigators of wildlife populations often utilize demographic indicators to understand the relationship between habitat characteristics and population viability. Assessments of corticosterone may enable earlier detection of populations at risk of decline because physiological adjustments to habitat disturbance occur before reproductive diminutions. Noninvasive methods to accomplish these assesments are important in species of concern, such as the greater sage grouse (GRSG). Therefore, we validated a radioimmunoassay that measures immunoreactive corticosterone metabolites (ICM) in fecal samples and used it to characterize the adrenocortical response of 15 GRSG exposed to capture, intravenous injection of 50 IU/kg adrenocorticotrophic hormone (ACTH) or saline, and 22 h of confinement. Those animals injected with ACTH exhibited a more sustained (P = 0.0139) and less variable (P = 0.0012) response than those injected with saline, indicating different levels of adrenocortical activity. We also found that potential field-collection protocols of fecal samples did not alter ICM concentrations: samples held at 4??C for up to 16 h contained similar levels of ICM as those frozen (-20??C) immediately. This study demonstrates a multiphasic adrenocortical response that varied with the level of stimulation and indicates that the assay used to measure this phenomenon is applicable for studies of wild GRSG. ?? 2009 by The University of Chicago. All rights reserved.

  3. The adrenocortical response of greater sage grouse (Centrocercus urophasianus) to capture, ACTH injection, and confinement, as measured in fecal samples.

    PubMed

    Jankowski, M D; Wittwer, D J; Heisey, D M; Franson, J C; Hofmeister, E K

    2009-01-01

    Investigators of wildlife populations often utilize demographic indicators to understand the relationship between habitat characteristics and population viability. Assessments of corticosterone may enable earlier detection of populations at risk of decline because physiological adjustments to habitat disturbance occur before reproductive diminutions. Noninvasive methods to accomplish these assessments are important in species of concern, such as the greater sage grouse (GRSG). Therefore, we validated a radioimmunoassay that measures immunoreactive corticosterone metabolites (ICM) in fecal samples and used it to characterize the adrenocortical response of 15 GRSG exposed to capture, intravenous injection of 50 IU/kg adrenocorticotrophic hormone (ACTH) or saline, and 22 h of confinement. Those animals injected with ACTH exhibited a more sustained (P = 0.0139) and less variable (P = 0.0012) response than those injected with saline, indicating different levels of adrenocortical activity. We also found that potential field-collection protocols of fecal samples did not alter ICM concentrations: samples held at 4 degrees C for up to 16 h contained similar levels of ICM as those frozen (-20 degrees C) immediately. This study demonstrates a multiphasic adrenocortical response that varied with the level of stimulation and indicates that the assay used to measure this phenomenon is applicable for studies of wild GRSG.

  4. The Adrenocortical Response of Greater Sage Grouse (Centrocercus urophasianus) to Capture, ACTH Injection, and Confinement, as Measured in Fecal Samples

    PubMed Central

    Jankowski, M. D.; Wittwer, D. J.; Heisey, D. M.; Franson, J. C.; Hofmeister, E. K.

    2009-01-01

    Investigators of wildlife populations often utilize demographic indicators to understand the relationship between habitat characteristics and population viability. Assessments of corticosterone may enable earlier detection of populations at risk of decline because physiological adjustments to habitat disturbance occur before reproductive diminutions. Noninvasive methods to accomplish these assesments are important in species of concern, such as the greater sage grouse (GRSG). Therefore, we validated a radioimmunoassay that measures immunoreactive corticosterone metabolites (ICM) in fecal samples and used it to characterize the adrenocortical response of 15 GRSG exposed to capture, intravenous injection of 50 IU/kg adrenocorticotrophic hormone (ACTH) or saline, and 22 h of confinement. Those animals injected with ACTH exhibited a more sustained (P = 0.0139) and less variable (P = 0.0012) response than those injected with saline, indicating different levels of adrenocortical activity. We also found that potential field-collection protocols of fecal samples did not alter ICM concentrations: samples held at 4°C for up to 16 h contained similar levels of ICM as those frozen (−20°C) immediately. This study demonstrates a multiphasic adrenocortical response that varied with the level of stimulation and indicates that the assay used to measure this phenomenon is applicable for studies of wild GRSG. PMID:19199814

  5. U-937 Toxicity Testing of Lunar Dust Stimulant (JSC-1A-vf)

    NASA Technical Reports Server (NTRS)

    Bales, Kristyn; Hammond, Dianne; Wallace, William; Jeevarajan, Antony

    2007-01-01

    With NASA planning to extend the human presence to the moon by 2020, the dangers of the lunar environment must be assessed and appropriate countermeasures must be developed. Possible toxic effects of the lunar dust are of particular importance to human health because of the dust's chemical composition, reactivity, and small size. This project focuses on the toxicity of lunar dust stimulant (JSC-1A-vf), in both its active and passive forms, using U-937 human monocyte cells. Simulant was mechanically activated from its passive form by grinding, and its ability to produce hydroxyl radicals was determined. To test for toxicity, active and passivated simulant was diluted in media and applied to the cells for various time periods. Toxicity was then estimated using flow cytometry on the Guava Personal Cell Analysis system. Preliminary results suggest that passivated stimulant is slightly toxic, with an increase in toxicity for activated stimulant. Toxicity results may be affected by cell lysing behavior and quenching of hydroxyl radical production by the cell media.

  6. Novel Air Stimulation MR-Device for Intraoral Quantitative Sensory Cold Testing

    PubMed Central

    Brönnimann, Ben; Meier, Michael L.; Hou, Mei-Yin; Parkinson, Charles; Ettlin, Dominik A.

    2016-01-01

    The advent of neuroimaging in dental research provides exciting opportunities for relating excitation of trigeminal neurons to human somatosensory perceptions. Cold air sensitivity is one of the most frequent causes of dental discomfort or pain. Up to date, devices capable of delivering controlled cold air in an MR-environment are unavailable for quantitative sensory testing. This study therefore aimed at constructing and evaluating a novel MR-compatible, computer-controlled cold air stimulation apparatus (CASA) that produces graded air puffs. CASA consisted of a multi-injector air jet delivery system (AJS), a cold exchanger, a cooling agent, and a stimulus application construction. Its feasibility was tested by performing an fMRI stimulation experiment on a single subject experiencing dentine cold sensitivity. The novel device delivered repetitive, stable air stimuli ranging from room temperature (24.5°C ± 2°C) to −35°C, at flow rates between 5 and 17 liters per minute (l/min). These cold air puffs evoked perceptions similar to natural stimuli. Single-subject fMRI-analysis yielded brain activations typically associated with acute pain processing including thalamus, insular and cingulate cortices, somatosensory, cerebellar, and frontal brain regions. Thus, the novel CASA allowed for controlled, repetitive quantitative sensory testing by using air stimuli at graded temperatures (room temperature down to −35°C) while simultaneously recording brain responses. No MR-compatible stimulation device currently exists that is capable of providing non-contact natural-like stimuli at a wide temperature range to tissues in spatially restricted areas such as the mouth. The physical characteristics of this novel device thus holds promise for advancing the field of trigeminal and spinal somatosensory research, namely with respect to comparing therapeutic interventions for dentine hypersensitivity. PMID:27445771

  7. Test-retest reliability of evoked heat stimulation BOLD fMRI.

    PubMed

    Upadhyay, Jaymin; Lemme, Jordan; Anderson, Julie; Bleakman, David; Large, Thomas; Evelhoch, Jeffrey L; Hargreaves, Richard; Borsook, David; Becerra, Lino

    2015-09-30

    To date, the blood oxygenated-level dependent (BOLD) functional magnetic resonance imaging (fMRI) technique has enabled an objective and deeper understanding of pain processing mechanisms embedded within the human central nervous system (CNS). In order to further comprehend the benefits and limitations of BOLD fMRI in the context of pain as well as the corresponding subjective pain ratings, we evaluated the univariate response, test-retest reliability and confidence intervals (CIs) at the 95% level of both data types collected during evoked stimulation of 40°C (non-noxious), 44°C (mildly noxious) and a subject-specific temperature eliciting a 7/10 pain rating. The test-retest reliability between two scanning sessions was determined by calculating group-level interclass correlation coefficients (ICCs) and at the single-subject level. Across the three stimuli, we initially observed a graded response of increasing magnitude for both VAS (visual analog score) pain ratings and fMRI data. Test-retest reliability was observed to be highest for VAS pain ratings obtained during the 7/10 pain stimulation (ICC=0.938), while ICC values of pain fMRI data for a distribution of CNS structures ranged from 0.5 to 0.859 (p<0.05). Importantly, the upper and lower confidence interval CI bounds reported herein could be utilized in subsequent trials involving healthy volunteers to hypothesize the magnitude of effect required to overcome inherent variability of either VAS pain ratings or BOLD responses evoked during innocuous or noxious thermal stimulation. PMID:26072245

  8. The Role of ACTH and Corticosteroids for Sepsis and Septic Shock: An Update

    PubMed Central

    Annane, Djillali

    2016-01-01

    Sepsis is a common disorder associated with high morbidity and mortality. It is now defined as an abnormal host response to infection, resulting in life-threatening dysfunction of organs. There is evidence from in vitro and in vivo experiments in various animal models and in patients that endotoxin or sepsis may directly and indirectly alter the hypothalamic–pituitary–adrenal response to severe infection. These alterations may include necrosis or hemorrhage or inflammatory mediator-mediated decreased ACTH synthesis, steroidogenesis, cortisol delivery to tissues, clearance from plasma, and decreased sensitivity of tissues to cortisol. Disruption of the hypothalamic–pituitary–adrenal axis may translate in patients with sepsis into cardiovascular and other organ dysfunction, and eventually an increase in the risk of death. Exogenous administration of corticosteroids at moderate dose, i.e., <400 mg of hydrocortisone or equivalent for >96 h, may help reversing sepsis-associated shock and organ dysfunction. Corticosteroids may also shorten the duration of stay in the ICU. Except for increased blood glucose and sodium levels, treatment with corticosteroids was rather well tolerated in the context of clinical trials. The benefit of treatment on survival remains controversial. Based on available randomized controlled trials, the likelihood of survival benefit is greater in septic shock versus sepsis patients, in sepsis with acute respiratory distress syndrome or with community-acquired pneumonia versus patients without these conditions, and in patients with a blunted cortisol response to 250 μg of ACTH test versus those with normal response. PMID:27379022

  9. Unusual visual stimulation in dynamic balance conditions: proposal for a space motion sickness test

    NASA Astrophysics Data System (ADS)

    Séverac, Alexandra; Bessou, Paul; Pagès, Bernard

    1994-08-01

    We previously demonstrated the efficiency of normal vision/unusual vestibular cues conflict to induce motion sickness. In the present study, we investigate whether, inversely, unusual visual information/normal vestibular function conflict also elicited motion sickness. The experiments were again carried out in dynamic balance conditions to increase proprioceptive input. Circular translation of the visual field with diplopia were produced by rotating Fresnel prismatic glasses. The stimulation triggered SMS-like symptoms and dynamic balance disturbance. A positive relationship was found between discomfort and balance disturbance. Unusual visual information should therefore be included in Space Motion Sickness susceptibility testing.

  10. A comparison of pulmonary function tests for postthoracotomy pain using cryoanalgesia and transcutaneous nerve stimulation.

    PubMed

    Rooney, S M; Jain, S; McCormack, P; Bains, M S; Martini, N; Goldiner, P L

    1986-02-01

    The beneficial effects of transcutaneous nerve stimulation (TNS) and cryoanalgesia for post-thoracotomy pain were compared against each other and against a control group through pulmonary function testing in the immediate and delayed postoperative period. Patients receiving cryoanalgesia did not perform well in the first 24 hours after operation. However, by the fifth postoperative day, they did as well as or even better than the TNS patients. Both cryoanalgesia and TNS were significantly effective in the management of postoperative pain as compared with controls. PMID:3484939

  11. Naloxone inhibits and morphine potentiates the adrenal steroidogenic response to ACTH

    NASA Technical Reports Server (NTRS)

    Heybach, J. P.; Vernikos, J.

    1981-01-01

    The administration of morphine to hypophysectomized rats potentiated the steroidogenic response of the adrenal cortex to exogenous adrenocorticotrophic hormone (ACTH) in a dose-dependent fashion. Conversely, the opiate antagonist naloxone inhibited the adrenal response to ACTH. Naloxone pretreatment also antagonized the potentiating effect of morphine on ACTH-induced steroidogenesis in a dose-dependent manner. Neither morphine nor naloxone, administered to hypophysectomized rats, had any direct effect on adrenal steroidogenesis. These adrenal actions were stereospecific since neither the (+)-stereoisomer of morphine, nor that or naloxone, had any effect on the adrenal response to ACTH. The administration of human beta-endorphin to hypophysectomized rats had no effect on the adrenal corticosterone concentration nor did it alter the response of the adrenal gland to ACTH. These results indicate that morphine can potentiate the action of ACTH on the adrenal by a direct, stereospecific, dose-dependent mechanism that is prevented by naloxone pretreatment and which may involve competition for ACTH receptors on the corticosterone-secreting cells of the adrenal cortex.

  12. Effect of ACTH on plasma corticosterone and cortisol in eagles and condors

    USGS Publications Warehouse

    Zenoble, R.D.; Kemppainen, R.J.; Young, D.W.; Carpenter, J.W.

    1985-01-01

    The effect of ACTH on plasma corticosterone and cortisol was determined in 12 eagles (Haliaeetus leucocephalus) and in 6 Andean condors (Vultur gryphus). In all raptors, the concentration of plasma corticosterone was substantially greater than that of cortisol. After ACTH administration, the eagles had a marked increase (P less than 0.001) in plasma corticosterone concentrations, but not in plasma cortisol. Administration of saline solution did not induce increased plasma corticosterone concentrations in the eagles. The condors had a smaller increase (P less than 0.002) in plasma corticosterone concentrations after ACTH administration, as compared with that of the eagles. However, administration of saline solution in 2 condors resulted in an increase in corticosterone similar to the increase after ACTH administration. In the condor, a stress-related release of endogenous ACTH may have an effect similar to that induced by exogenously administered ACTH. Plasma cortisol concentrations did not increase significantly after administration of ACTH or saline solution in either raptor species.

  13. Control of ACTH secretion by excitatory amino acids: functional significance and clinical implications.

    PubMed

    Jezova, Daniela

    2005-12-01

    The involvement of excitatory amino acids in the control of ACTH release is well established. Activation of ionotropic glutamate receptors has a stimulatory effect on ACTH release, while the role of metabotropic receptors is not yet understood in detail. Glutamatergic regulation of ACTH release has a clear significance for the stress response and neuroendocrine functions during development. A dysregulation of the hypothalamic-pituitary-adrenocortical (HPA) axis has been reported in several psychiatric and neurological disorders. So far, only fractional indices on the clinical importance of the interaction between glutamate and ACTH secretion have been obtained in both preclinical and clinical studies. Some antidepressant drugs, such as tianeptine, which were found to modulate ACTH release, appear to interfere with brain glutamatergic system. Changes in ACTH and cortisol release may be of importance for mood stabilizing effects of antiepileptic drugs modulating glutamate release, such as lamotrigine. Brain glutamate and HPA axis interaction seems to be of importance in alcohol and drug abuse. Little information is available on ACTH release in response to glutamate-modulating drugs used in the treatment of schizophrenia and Alzheimer disease. Nevertheless, pharmacological interventions influencing interaction between glutamate and the HPA axis are promising treatment possibilities in psychiatry and neurology.

  14. A rare cause of Cushing's syndrome: an ACTH-secreting phaeochromocytoma

    PubMed Central

    Folkestad, Lars; Andersen, Marianne Skovsager; Nielsen, Anne Lerberg; Glintborg, Dorte

    2014-01-01

    Excess glucocorticoid levels cause Cushing's syndrome (CS) and may be due to pituitary, adrenal or ectopic tumours. Adrenocorticotropic hormone (ACTH) levels are useful in identifying adrenal tumours. In rare cases, ACTH-producing phaeochromocytomas are the cause of CS. We present two cases of ACTH-secreting phaeochromocytoma as the underlying cause of CS. In both cases, female patients presented with the classical clinical signs of CS and an adrenal mass. High ACTH levels raised the suspicion of an ACTH-secreting phaeochromocytoma. The diagnosis was confirmed by urinary catecholamine levels and positive fluorine-18-L-dihydroxyphenylalanine (18F-DOPA) positron emission tomography (PET) CT (Case 1) and fluorodeoxyglucose PET-CT (Case 2). Both patients were treated with an α-blocker prior to surgical intervention. The two cases underline the importance of thorough diagnostic workup in patients with CS. An ACTH-secreting phaeochromocytoma should be checked for in patients with an adrenal mass and elevated ACTH levels. PMID:25297883

  15. The pituitary V3 vasopressin receptor and the corticotroph phenotype in ectopic ACTH syndrome.

    PubMed

    de Keyzer, Y; Lenne, F; Auzan, C; Jégou, S; René, P; Vaudry, H; Kuhn, J M; Luton, J P; Clauser, E; Bertagna, X

    1996-03-01

    Ectopic ACTH secretion occurs in highly differentiated and rather indolent tumors like bronchial carcinoids or, in contrast, in various types of aggressive and poorly differentiated neuroendocrine tumors. We explored this phenomenon using the recently cloned human pituitary V3 vasopressin receptor as an alternate molecular marker of the corticotroph phenotype. Expression of V3 receptor, corticotrophin releasing hormone (CRH) receptor, and proopiomelanocortin (POMC) genes was examined in tumors of pituitary and nonpituitary origin. A comparative RT-PCR approach revealed signals for both V3 receptor and CHR receptor mRNAs in 17 of 18 ACTH-secreting pituitary adenomas, and 6 of 6 normal pituitaries; in six growth hormone- or prolactin-secreting adenomas, a very faint V3 receptor signal was observed in three cases, and CRH receptor signal was undetected in all. Six of eight bronchial carcinoids responsible for the ectopic ACTH syndrome had both POMC and V3 receptor signals as high as those in ACTH-secreting pituitary adenomas; in contrast, no POMC signal and only a very faint V3 receptor signal were detected in six of eight nonsecreting bronchial carcinoids. Northern blot analysis showed V3 receptor mRNA of identical size in ACTH-secreting bronchial carcinoids and pituitary tumors. Other types of nonpituitary tumors responsible for ectopic ACTH syndrome presented much lower levels of both POMC and V3 receptor gene expression than those found in ACTH-secreting bronchial carcinoids. In contrast with the V3 receptor, CRH receptor mRNA was detected in the majority of neuroendocrine tumors irrespective of their POMC status. These results show that expression of the V3 receptor gene participates in the corticotroph phenotype. Its striking association with ACTH-secreting bronchial carcinoids defines a subset of nonpituitary tumors in which ectopic POMC gene expression is but one aspect of a wider process of corticotroph cell differentiation, and opens new possibilities of

  16. The effects of fasting and refeeding on adrenal cortex morphometry and serum concentrations of ACTH and corticosterone in young and old male rats.

    PubMed

    Kmiec, Z; Pokrywka, L; Kotlarz, G; Mysliwski, A

    2006-11-01

    The impairment of homeostatic mechanisms in ageing becomes often apparent upon physiological or pathological stimulation. We have previously shown that fasting and refeeding revealed the existence of age-related changes of carbohydrate and lipid metabolism. Because fuel metabolism is partially controlled by corticosteroids we decided to determine the effects of refeeding on adrenal gland morphometry, ACTH, and corticosterone serum levels in young (5 mo) and (20 mo) old male Wistar rats. Fasting for 48 h did not change serum ACTH and corticosterone in both age groups. ACTH level did not change after 24 h of refeeding in young and old rats. However, in old, but not young animals, refeeding resulted in the decrease of corticosterone serum concentration. The relative weight of adrenal gland (% of body weight) did not change significantly with age (p=0.05). Fasting for 48 h induced in old rats but not in young ones increase of relative adrenal weight, and the volume of the reticular zone. Refeeding reduced adrenal volume, fascicular zone and reticular zone. Refeeding for 24 h decreased the total volume of adrenal gland of old rats due to a decline of the volumes of fascicular and reticular zones. In young rats refeeding reduced the volume of reticular zone. It is concluded that refeeding revealed ageing-dependent decline in the secretion of corticosterone, the key hormone of prolonged stress response.

  17. Spectral F-test power evaluation in the EEG during intermittent photic stimulation.

    PubMed

    de Sá, Antonio Mauricio F L Miranda; Cagy, Mauricio; Lazarev, Vladimir V; Infantosi, Antonio Fernando C

    2006-06-01

    Intermittent photic stimulation (IPS) is an important functional test, which can induce the photic driving in the electroencephalogram (EEG). It is capable of enhancing latent oscillations manifestations not present in the resting EEG. However, for adequate quantitative evaluation of the photic driving, these changes should be assessed on a statistical basis. With this aim, the sampling distribution of spectral F test was investigated. On this basis, confidence limits of the SFT-estimate could be obtained for different practical situations, in which the signal-to-noise ratio and the number of epochs used in the estimation may vary. The technique was applied to the EEG of 10 normal subjects during IPS, and allowed detecting responses not only at the fundamental IPS frequency but also at higher harmonics. It also permitted to assess the strength of the photic driving responses and to compare them in different derivations and in different subjects.

  18. Control of Stress-Induced ACTH Secretion by Vasopressin and CRH: Additional Evidence.

    PubMed

    Ramos, Adriana T; Tufik, Sergio; Troncone, Lanfranco R P

    2016-01-01

    Vasopressin and CRH have complementary roles in the secretion of ACTH following different stress modalities. The concomitant use of V1b and CRF1 receptor antagonists completely inhibits ACTH secretion in response to different stress modalities. The combination of the CRF1 antagonist SSR125543 with the V1b antagonist SSR149415 effectively suppressed plasma ACTH 1.30 h after injection in rats stressed by ether vapor inhalation for 1 min, restraint stress for 1 h or forced swimming for 5 min. The duration of the effect was also studied. The CRF1 antagonist effectively suppressed ACTH secretion in restraint stress, while the V1b antagonist was effective against ether inhalation. Both antagonists were necessary to block the forced swimming stress response. SSR125543 induced a prolonged effect and can be used in a model of prolonged HPA axis blockade. PMID:27221315

  19. The food reaching test: a sensitive test of behavioral improvements by deep brain stimulation in MPTP-treated monkey.

    PubMed

    Asakawa, Tetsuya; Sugiyama, Kenji; Akamine, Souichi; Yokoyama, Chihiro; Shukuri, Miho; Mizuma, Hiroshi; Tsukada, Hideo; Onoe, Hirotaka; Namba, Hiroki

    2012-10-01

    We modified an objective behavioral test, namely the food reaching test (FRT), for quantitative assessment of motor performance improved by deep brain stimulation (DBS) of the subthalamic nucleus (STN) in the Parkinsonian monkeys. The symptomatic features and their severity in 3 monkeys treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were evaluated with a subjective monkey Parkinson's disease rating scale (PDRS). We then performed STN-DBS with the minimum current intensity that stopped the tremor. The time required for the monkeys to pick up all 5 pieces of potato (FRT time) was measured as a major index to evaluate bradykinesia. The success rate was adopted as another index for assessing overall motor impairments. Although both FRT time and PDRS score were similarly improved by STN-DBS, change of FRT time appeared more sensitive than that of PDRS scores. FRT is an easily trained behavioral test with high objectivity and sensitivity that can be applied for assessing motor performance in MPTP-treated monkeys during experiments in a restrained condition such as functional imaging of the brain.

  20. The effect of splanchnic nerve stimulation on adrenocortical activity in conscious calves.

    PubMed Central

    Edwards, A V; Jones, C T

    1987-01-01

    1. Right adrenal and various cardiovascular responses to stimulation of the peripheral end of the right splanchnic nerve have been investigated in the presence and absence of exogenous adrenocorticotrophin, ACTH1-24, (5 ng min-1 kg-1). The adrenal-clamp technique was employed in conscious calves in which the pituitary stalk had been cauterized 3-4 days previously. 2. The I.V. infusion of ACTH1-24 increased mean plasma ACTH concentration by about 1200 pg/ml and mean right adrenal cortisol output by about 500 ng min-1 kg-1. Stimulation of the peripheral end of the right splanchnic nerve at 4 Hz for 10 min produced a further rise in cortisol output, amounting to about 400 ng min-1 kg-1 (P less than 0.01). These changes in output were reflected accurately by changes in peripheral plasma cortisol concentration. 3. Closely similar amounts of adrenaline were released in response to splanchnic nerve stimulation in the presence and absence of exogenous ACTH. In the presence of ACTH the average mean output of noradrenaline (58 +/- 2 ng min-1 kg-1) was significantly less than that of adrenaline (102 +/- 4 ng min-1 kg-1; P less than 0.001), whereas the corresponding values were not significantly different in the absence of ACTH. 4. These results also confirm the fact that the fall in adrenal vascular resistance which occurs during splanchnic nerve stimulation is substantially reduced by ACTH, as is the rise in met5-enkephalin output. 5. It is concluded that the splanchnic innervation is capable of enhancing the secretion of adrenal glucocorticoids in response to ACTH under physiological conditions in the conscious calf. PMID:3040966

  1. Factors to predict positive results of gonadotropin releasing hormone stimulation test in girls with suspected precocious puberty.

    PubMed

    Nam, Hyo-Kyoung; Rhie, Young Jun; Son, Chang Sung; Park, Sang Hee; Lee, Kee-Hyoung

    2012-02-01

    Sometimes, the clinical findings and the results of the gonadotropin-releasing hormone (GnRH) stimulation test are inconsistent in girls with early breast development and bone age advancement. We aimed to investigate the factors predicting positive results of the GnRH stimulation test in girls with suspected central precocious puberty (CPP). We reviewed the records of 574 girls who developed breast budding before the age of 8 yr and underwent the GnRH stimulation test under the age of 9 yr. Positive results of the GnRH stimulated peak luteinizing hormone (LH) level were defined as 5 IU/L and over. Girls with the initial positive results (n = 375) showed accelerated growth, advanced bone age and higher serum basal LH, follicle-stimulating hormone, and estradiol levels, compared to those with the initial negative results (n = 199). Girls with the follow-up positive results (n = 64) showed accelerated growth and advanced bone age, compared to those with the follow-up negative results. In the binary logistic regression, the growth velocity ratio was the most significant predictive factor of positive results. We suggest that the rapid growth velocity is the most useful predictive factor for positive results in the GnRH stimulation test in girls with suspected precocious puberty.

  2. TEST OF DEUTSCH'S DRIVE-DECAY THEORY OF REWARDING SELF-STIMULATION OF THE BRAIN.

    PubMed

    PLISKOFF, S S; HAWKINS, T D

    1963-08-30

    Deutsch's theory of intracranial self-stimulation generates experimental predictions regarding the effects of both free stimulation of the brain and the pre-extinction training procedure on extinction behavior after rewarding stimulation of the brain. The results of one experiment confirmed the prediction regarding free stimulation; the other experiment did not provide the expected result. We concluded that Deutsch's theory, in its present form, is of restricted enerality.

  3. Contribution to the improvement of heritage mural painting non-destructive testing by stimulated infrared thermography

    NASA Astrophysics Data System (ADS)

    Bodnar, Jean-Luc; Mouhoubi, Kamel; Di Pallo, Luigi; Detalle, Vincent; Vallet, Jean-Marc; Duvaut, Thierry

    2013-10-01

    Non-destructive testing of heritage mural paintings by means of stimulated infrared thermography has now become rather efficient [1-14]. However, pigments, which form a pictorial layer, have contrasting radiative properties possibly leading to artifact detection. In this paper, attempts to alleviate this difficulty are presented. Based on the spectroscopic study of different paint layers, one can argue that, in the medium infrared field, this radiative disparity decreases significantly. Then, with similar settings, it can be shown that ceramic radiative sources allow reaching this wavelength band. Finally, on the basis of a study carried out on an academic sample and a partial copy of a fresco from the cathedral of Angers, combining ceramic heat sources with a laboratory SAMMTHIR experimental setup enables to make real headway in terms of defects' detection.

  4. Involuntary language switching in two bilingual patients during the Wada test and intraoperative electrocortical stimulation.

    PubMed

    Kho, Kuan H; Duffau, Hugues; Gatignol, Peggy; Leijten, Frans S S; Ramsey, Nick F; van Rijen, Peter C; Rutten, Geert-Jan M

    2007-04-01

    We present two bilingual patients without language disorders in whom involuntary language switching was induced. The first patient switched from Dutch to English during a left-sided amobarbital (Wada) test. Functional magnetic resonance imaging yielded a predominantly left-sided language distribution similar for both languages. The second patient switched from French to Chinese during intraoperative electrocortical stimulation of the left inferior frontal gyrus. We conclude that the observed language switching in both cases was not likely the result of a selective inhibition of one language, but the result of a temporary disruption of brain areas that are involved in language switching. These data complement the few lesion studies on (involuntary or unintentional) language switching, and add to the functional neuroimaging studies of switching, monitoring, and controlling the language in use.

  5. The usefulness of the leuprolide stimulation test as a diagnostic method of idiopathic central precocious puberty in girls.

    PubMed

    Carretto, F; Salinas-Vert, I; Granada-Yvern, M L; Murillo-Vallés, M; Gómez-Gómez, C; Puig-Domingo, M; Bel, J

    2014-12-01

    Central precocious puberty (CPP) diagnosis is based on clinical evaluation, but hormonal evaluation is crucial. The aim of the study was to evaluate the usefulness of the leuprolide stimulation test for diagnosis of idiopathic CPP. Sixty-one girls, aged 5-8 years, were evaluated retrospectively for premature breast development. According to clinical evolution, 28 had progressive puberty and 33 nonprogressive puberty. All underwent a leuprolide stimulation test. Cutoff points, sensitivity, and specificity for gonadotropins and estradiol were determined by receiver operating characteristic (ROC) curves. Cutoff points for CPP were: baseline LH: > 0.1 mUI/l, FSH: > 2.3 mUI/l, LH/FSH ratio: > 0.23, estradiol: > 12 pg/ml; and stimulated LH: > 5.5 mUI/l, LH/FSH ratio: > 0.24, estradiol: > 79.67 pg/ml. The best diagnostic efficiency for progressive puberty were stimulated LH/FSH ratio (sensitivity: 100%, specificity 94%) followed by stimulated LH (sensitivity: 93%, specificity: 100%). Stimulated LH/FSH ratio and LH resulted in the most useful parameters for the diagnosis of CPP. Stimulated estradiol did not add more information.

  6. ACTH Modulates PTP-PEST Activity and Promotes Its Interaction With Paxillin.

    PubMed

    Gorostizaga, Alejandra Beatriz; Mori Sequeiros Garcia, M Mercedes; Acquier, Andrea B; Lopez-Costa, Juan J; Mendez, Carlos F; Maloberti, Paula M; Paz, Cristina

    2016-09-01

    Adrenocorticotropic hormone (ACTH) treatment has been proven to promote paxillin dephosphorylation and increase soluble protein tyrosine phosphatase (PTP) activity in rat adrenal zona fasciculata (ZF). Also, in-gel PTP assays have shown the activation of a 115-kDa PTP (PTP115) by ACTH. In this context, the current work presents evidence that PTP115 is PTP-PEST, a PTP that recognizes paxillin as substrate. PTP115 was partially purified from rat adrenal ZF and PTP-PEST was detected through Western blot in bioactive samples taken in each purification step. Immunohistochemical and RT-PCR studies revealed PTP-PEST expression in rat ZF and Y1 adrenocortical cells. Moreover, a PTP-PEST siRNA decreased the expression of this phosphatase. PKA phosphorylation of purified PTP115 isolated from non-ACTH-treated rats increased KM and VM . Finally, in-gel PTP assays of immunoprecipitated paxillin from control and ACTH-treated rats suggested a hormone-mediated increase in paxillin-PTP115 interaction, while PTP-PEST and paxillin co-localize in Y1 cells. Taken together, these data demonstrate PTP-PEST expression in adrenal ZF and its regulation by ACTH/PKA and also suggest an ACTH-induced PTP-PEST-paxillin interaction. J. Cell. Biochem. 117: 2170-2181, 2016. © 2016 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc.

  7. Effects of breeding season, testosterone and ACTH on the corticosterone response of free-ranging male fence lizards (Sceloporus undulatus).

    PubMed

    Klukowski, Matthew

    2011-09-01

    An attenuated stress response during the breeding season has been reported for several vertebrate species, but the underlying physiological mechanism has received little attention, particularly in reptiles. Modulation could involve changes in the capacity of the adrenal gland to secrete glucocorticoids in addition to upstream changes in the pituitary or hypothalamus. In this study the magnitude of the corticosterone response to capture and confinement was compared between the breeding and postbreeding season in adult male eastern fence lizards, Sceloporus undulatus. Males were captured in both seasons and subjected to the identical stressor of 4h of confinement. Plasma corticosterone levels in response to confinement were significantly lower in the breeding than the postbreeding season. The effect of testosterone on the stress response was tested by experimentally elevating plasma testosterone levels via silastic implants in free-living males during the postbreeding season. Males with experimentally elevated testosterone exhibited significantly weaker corticosterone responses to 1h of confinement than sham-implanted males. Finally the capacity of the adrenal glands to secrete corticosterone during the breeding season was tested by challenging males with adrenocorticotropin (ACTH) injections. In spite of naturally suppressed corticosterone responses during the breeding season, males nonetheless responded robustly to ACTH. Altogether these results suggest that modulation resides upstream of the adrenal gland, as has been shown in some arctic-breeding avian species, and likely involves seasonal changes in testosterone levels.

  8. Presence of ACTH and beta-endorphin immunoreactive molecules in the freshwater snail Planorbarius corneus (L.) (Gastropoda, Pulmonata) and their possible role in phagocytosis.

    PubMed

    Ottaviani, E; Petraglia, F; Montagnani, G; Cossarizza, A; Monti, D; Franceschi, C

    1990-01-01

    The presence of ACTH and beta-endorphin immunoreactive molecules in the cell-free hemolymph and in the hemocytes of the freshwater snail Planorbarius corneus were demonstrated by immunocytochemistry and RIA tests. Only spreading phagocytic hemocytes were positive, in contrast with other hemocytes devoid of phagocytic activity, i.e., round hemocytes. These data were confirmed by flow cytometry. Another cell type with marked phagocytic activity, i.e., digestive cells of digestive gland, were also positive to anti-ACTH. Corticotropin-releasing factor immunoreactive molecules were found in the cell-free hemolymph and hemocytes, by RIA. Our data suggest that cells with phagocytic activity, the oldest immune response, may represent a suitable model to unravel the tangled web of the common ancestor of the immune and the neuroendocrine systems.

  9. Drilling, completion, stimulation, and testing of Hardy HW{number_sign}1 well, Putnam County, West Virginia. Final report

    SciTech Connect

    Overbey, W.K. Jr.; Carden, R.S.; Locke, C.D.; Salamy, S.P.

    1992-03-01

    This report discusses the detailed field operations in drilling, logging, casing, completing, stimulating and testing the Hardy HW No. l well located in Union District, Putnam County, West Virginia. The project was designed and managed by BDM in cooperation with Cabot Oil and Gas Corporation. The well was spudded on November 29, 1989 and was completed at a total measured depth of 6406 feet on December 29, 1989. The well was drilled on an average azimuth of 335 degrees with a total horizontal displacement of 2618 feet. Approximately 1035 feet of the well had an inclination higher than 86 degrees, while 2212 feet of the well had an inclination greater than 62 degrees. The well was partitioned into five zones for stimulation purposes. Four zones were stimulated during three stimulation operations (Zones 3 and 4 were stimulated together). Zone 1 stimulation was a successful foam frac while the stimulations on Zones 2, 3-4 were Partially successful. Initial gas production rates were 4.5 times greater than the natural production rate. After 21 months, gas produced from the BDM/Cabot well has declined at a rate about one-half that of a conventional vertical well in the area. This horizontal well is projected to produce 475 million cubic feet of gas over a 30-year period.

  10. Drilling, completion, stimulation, and testing of Hardy HW[number sign]1 well, Putnam County, West Virginia

    SciTech Connect

    Overbey, W.K. Jr.; Carden, R.S.; Locke, C.D.; Salamy, S.P.

    1992-03-01

    This report discusses the detailed field operations in drilling, logging, casing, completing, stimulating and testing the Hardy HW No. l well located in Union District, Putnam County, West Virginia. The project was designed and managed by BDM in cooperation with Cabot Oil and Gas Corporation. The well was spudded on November 29, 1989 and was completed at a total measured depth of 6406 feet on December 29, 1989. The well was drilled on an average azimuth of 335 degrees with a total horizontal displacement of 2618 feet. Approximately 1035 feet of the well had an inclination higher than 86 degrees, while 2212 feet of the well had an inclination greater than 62 degrees. The well was partitioned into five zones for stimulation purposes. Four zones were stimulated during three stimulation operations (Zones 3 and 4 were stimulated together). Zone 1 stimulation was a successful foam frac while the stimulations on Zones 2, 3-4 were Partially successful. Initial gas production rates were 4.5 times greater than the natural production rate. After 21 months, gas produced from the BDM/Cabot well has declined at a rate about one-half that of a conventional vertical well in the area. This horizontal well is projected to produce 475 million cubic feet of gas over a 30-year period.

  11. Laser heat stimulation of tiny skin areas adds valuable information to quantitative sensory testing in postherpetic neuralgia.

    PubMed

    Franz, Marcel; Spohn, Dorothee; Ritter, Alexander; Rolke, Roman; Miltner, Wolfgang H R; Weiss, Thomas

    2012-08-01

    Patients suffering from postherpetic neuralgia often complain about hypo- or hypersensation in the affected dermatome. The loss of thermal sensitivity has been demonstrated by quantitative sensory testing as being associated with small-fiber (Aδ- and C-fiber) deafferentation. We aimed to compare laser stimulation (radiant heat) to thermode stimulation (contact heat) with regard to their sensitivity and specificity to detect thermal sensory deficits related to small-fiber dysfunction in postherpetic neuralgia. We contrasted detection rate of laser stimuli with 5 thermal parameters (thresholds of cold/warm detection, cold/heat pain, and sensory limen) of quantitative sensory testing. Sixteen patients diagnosed with unilateral postherpetic neuralgia and 16 age- and gender-matched healthy control subjects were tested. Quantitative sensory testing and laser stimulation of tiny skin areas were performed in the neuralgia-affected skin and in the contralateral homologue of the neuralgia-free body side. Across the 5 thermal parameters of thermode stimulation, only one parameter (warm detection threshold) revealed sensory abnormalities (thermal hypoesthesia to warm stimuli) in the neuralgia-affected skin area of patients but not in the contralateral area, as compared to the control group. In contrast, patients perceived significantly less laser stimuli both in the affected skin and in the contralateral skin compared to controls. Overall, laser stimulation proved more sensitive and specific in detecting thermal sensory abnormalities in the neuralgia-affected skin, as well as in the control skin, than any single thermal parameter of thermode stimulation. Thus, laser stimulation of tiny skin areas might be a useful diagnostic tool for small-fiber dysfunction. PMID:22657400

  12. Usability testing of a monitoring and feedback tool to stimulate physical activity

    PubMed Central

    van der Weegen, Sanne; Verwey, Renée; Tange, Huibert J; Spreeuwenberg, Marieke D; de Witte, Luc P

    2014-01-01

    Introduction A monitoring and feedback tool to stimulate physical activity, consisting of an activity sensor, smartphone application (app), and website for patients and their practice nurses, has been developed: the ‘It’s LiFe!’ tool. In this study the usability of the tool was evaluated by technology experts and end users (people with chronic obstructive pulmonary disease or type 2 diabetes, with ages from 40–70 years), to improve the user interfaces and content of the tool. Patients and methods The study had four phases: 1) a heuristic evaluation with six technology experts; 2) a usability test in a laboratory by five patients; 3) a pilot in real life wherein 20 patients used the tool for 3 months; and 4) a final lab test by five patients. In both lab tests (phases 2 and 4) qualitative data were collected through a thinking-aloud procedure and video recordings, and quantitative data through questions about task complexity, text comprehensiveness, and readability. In addition, the post-study system usability questionnaire (PSSUQ) was completed for the app and the website. In the pilot test (phase 3), all patients were interviewed three times and the Software Usability Measurement Inventory (SUMI) was completed. Results After each phase, improvements were made, mainly to the layout and text. The main improvement was a refresh button for active data synchronization between activity sensor, app, and server, implemented after connectivity problems in the pilot test. The mean score on the PSSUQ for the website improved from 5.6 (standard deviation [SD] 1.3) to 6.5 (SD 0.5), and for the app from 5.4 (SD 1.5) to 6.2 (SD 1.1). Satisfaction in the pilot was not very high according to the SUMI. Discussion The use of laboratory versus real-life tests and expert-based versus user-based tests revealed a wide range of usability issues. The usability of the It’s LiFe! tool improved considerably during the study. PMID:24669188

  13. Efficiency test of filtering methods for the removal of transcranial magnetic stimulation artifacts on human electroencephalography with artificially transcranial magnetic stimulation-corrupted signals

    NASA Astrophysics Data System (ADS)

    Zilber, Nicolas A.; Katayama, Yoshinori; Iramina, Keiji; Erich, Wintermantel

    2010-05-01

    A new approach is proposed to test the efficiency of methods, such as the Kalman filter and the independent component analysis (ICA), when applied to remove the artifacts induced by transcranial magnetic stimulation (TMS) from electroencephalography (EEG). By using EEG recordings corrupted by TMS induction, the shape of the artifacts is approximately described with a model based on an equivalent circuit simulation. These modeled artifacts are subsequently added to other EEG signals—this time not influenced by TMS. The resulting signals prove of interest since we also know their form without the pseudo-TMS artifacts. Therefore, they enable us to use a fit test to compare the signals we obtain after removing the artifacts with the original signals. This efficiency test turned out very useful in comparing the methods between them, as well as in determining the parameters of the filtering that give satisfactory results with the automatic ICA.

  14. [Vascular exploration tests. Importance for the indications and monitoring of epidural medullary neuro-stimulation].

    PubMed

    Boccalon, H

    1992-01-01

    The clinical diagnosis must be enriched by quantifiable parameters when a new therapeutic method must be tested. We analyse the role of vascular explorations for epidural stimulation and limb arteriopathies. Four different fields of investigations can be defined. Accuracy of the diagnosis: The tests are useful to rule out some differential diagnoses of arterial involvement, and to establish the functional severity (stage III). 1--Treadmill test: nonischemic pain is ruled out: the evolution can be followed up. 2--Doppler velocimetry demonstrates the extent of the dominant arterial involvement in cases of associated lesions. 3--Arterial pressure gradients: their presence demonstrates significant lesions and allows detecting the affected levels. Quantification of severity: After detecting the lesions, their impact must be appreciated. From a macrocirculatory point of view, the measurement of pressures and flow rates is more sensitive than the Doppler study. From a microcirculatory point of view, the tcpO2 is very useful. 1--Arterial pressure: measured in the ankle and the first toe. There are three degrees: non-threatening ischemia (pulsatile Doppler, distal pressure exceeding 30 mm Hg), threatening ischemia (non pulsatile Doppler, distal pressure exceeding 30 mm Hg), irreversible ischemia (no more pulse, no more capillary flow). If there are arterial calcifications, the pressure in the toe must be measured. 2--Arterial flow rate: the average flow rate may be preserved in an arteriopathy, while the pulsatile rate is already degraded. Non invasive electromagnetic or nuclear magnetic resonance flowmeters measure the total muscular flow. Laser Doppler shows the cutaneous flow rate. 3--The tcpO2: normally greater than 60 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. A case of salicylazosulfapyridine (Salazopyrin)-induced acute pancreatitis with positive lymphocyte stimulation test (LST).

    PubMed

    Chiba, M; Horie, Y; Ishida, H; Arakawa, H; Masamune, O

    1987-04-01

    A case of acute pancreatitis induced by salicylazosulfapyridine (Salazopyrin, SASP) was reported. A 33-year-old man with ulcerative colitis was given SASP. Five weeks later, P-type serum amylase was found to be elevated. The amylase/creatinine clearance ratio (ACCR) and serum lipase were also elevated. There were neither subjective symptoms nor abnormal ultrasound findings in the pancrease. Lymphocyte stimulation test (LST) to SASP was positive. Asymptomatic pancreatitis by SASP was suspected and SASP administration was halted. Afterwards the abnormal data became normal. Readministration of SASP because of relapse caused an episode of pancreatitis similar to the first occasion. LST was negative before SASP intake and became positive after intake. Desensitization to SASP was unsuccessful. LST was negative before attempting desensitization and became positive when the dosage of SASP increased to 100 mg daily. This is the second case of acute pancreatitis reported to be induced by SASP and this is the first case in which LST to SASP was described. To our knowledge, this is also the first case in which a positive LST was described in drug-induced pancreatitis. This case provides evidence for the role of delayed type hypersensitivity in the etiopathogenesis of SASP allergy and of dose-independent drug-induced pancreatitis. PMID:2885242

  16. Characterization of a novel ACTH inducible cytochrome P-450 from rat adrenal microsomes

    SciTech Connect

    Otto, S.A.; Marcus, C.M.; Jefcoate, C.R. )

    1990-02-26

    In rat adrenal cortex 7,12 dimethylbenz(a)anthracene (DMBA) causes massive necrosis that is dependent of ACTH. This is related to an ACTH inducible adrenal microsomal cytochrome P-450 that catalyzes hydrocarbon metabolism. Rat adrenal microsomes, catalyze the formation of DMBA 3,4 diol a precursor of the bay region reactive electrophile DMBA 3,4 diol 1,2 oxide. Both DMBA metabolism and a 57Kd protein have disappeared from microsomes 30 days after hypophysectomy, but are restored by 14 days treatment with ACTH. Dexamethasone which fully suppresses ACTH only partially suppresses this activity. The 57 Kd protein was partially purified to a single major band in one step from solubilized microsomes by h.p.l.c. chromatography using detergent elution from a novel column that mimics phospholipid membranes. This preparation exhibits a specific content of 2 nm P-450/mg protein and a turnover number of 1,500pm DMBA/nm P-450/minutes. A polyclonal antisera raised against this preparation provides a single western blot corresponding to the 57Kd ACTH sensitive protein. This antibody did not blot microsomal P-450 c21, nor did selected antibodies from known families react with this adrenal P-450 protein, suggesting substantial sequence differences from known P-450's.

  17. The antinociceptive effect of stimulating the retrosplenial cortex in the rat tail-flick test but not in the formalin test involves the rostral anterior cingulate cortex.

    PubMed

    Reis, Gláucia Melo; Fais, Rafael Sobrano; Prado, Wiliam A

    2015-04-01

    The stimulation of the retrosplenial cortex (RSC) is antinociceptive in the rat tail-flick and formalin tests. The rat RSC is caudal to and send projections to the ipsilateral anterior cingulate cortex (ACC), which is also involved in pain processing. This study demonstrated that pre-treating the rostral (rACC), but not the caudal ACC with CoCl2 (1mM), or the rACC ablation increased the duration of the antinociceptive effect evoked by a 15-s period of electrical stimulation (AC, 60Hz, 20μA) of the RSC in the rat tail-flick. Injecting the GABA-A antagonist bicuculline (50ng/0.25μL), but not the GABA-B antagonist phaclofen (300ng/0.25μL) into the rACC also increased the duration of the stimulation-induced antinociception from the RSC. In contrast, the effects of rACC stimulation persisted after the injection of CoCl2 (1mM) into the RSC. The injection of CoCl2 into the rACC did not change the nociceptive behavior of rats during phase 1 of the formalin response but reduced licking response duration during phase 2. This effect was similar in sham or stimulated animals at the RSC. We conclude that the antinociceptive effect of stimulating the RSC in the rat tail-flick test is modulated by the rACC involving GABA-A receptors in this cortex. In contrast, the antinociceptive effect of stimulating the RSC in the formalin test does not involve the rACC.

  18. Ca2+ and K+ channels of normal human adrenal zona fasciculata cells: Properties and modulation by ACTH and AngII

    PubMed Central

    Enyeart, Judith A.

    2013-01-01

    In whole cell patch clamp recordings, we found that normal human adrenal zona fasciculata (AZF) cells express voltage-gated, rapidly inactivating Ca2+ and K+ currents and a noninactivating, leak-type K+ current. Characterization of these currents with respect to voltage-dependent gating and kinetic properties, pharmacology, and modulation by the peptide hormones adrenocorticotropic hormone (ACTH) and AngII, in conjunction with Northern blot analysis, identified these channels as Cav3.2 (encoded by CACNA1H), Kv1.4 (KCNA4), and TREK-1 (KCNK2). In particular, the low voltage–activated, rapidly inactivating and slowly deactivating Ca2+ current (Cav3.2) was potently blocked by Ni2+ with an IC50 of 3 µM. The voltage-gated, rapidly inactivating K+ current (Kv1.4) was robustly expressed in nearly every cell, with a current density of 95.0 ± 7.2 pA/pF (n = 64). The noninactivating, outwardly rectifying K+ current (TREK-1) grew to a stable maximum over a period of minutes when recording at a holding potential of −80 mV. This noninactivating K+ current was markedly activated by cinnamyl 1-3,4-dihydroxy-α-cyanocinnamate (CDC) and arachidonic acid (AA) and inhibited almost completely by forskolin, properties which are specific to TREK-1 among the K2P family of K+ channels. The activation of TREK-1 by AA and inhibition by forskolin were closely linked to membrane hyperpolarization and depolarization, respectively. ACTH and AngII selectively inhibited the noninactivating K+ current in human AZF cells at concentrations that stimulated cortisol secretion. Accordingly, mibefradil and CDC at concentrations that, respectively, blocked Cav3.2 and activated TREK-1, each inhibited both ACTH- and AngII-stimulated cortisol secretion. These results characterize the major Ca2+ and K+ channels expressed by normal human AZF cells and identify TREK-1 as the primary leak-type channel involved in establishing the membrane potential. These findings also suggest a model for cortisol

  19. Ectopic ACTH Production Leading to Diagnosis of Underlying Medullary Thyroid Carcinoma.

    PubMed

    Matheny, Leslee N; Wilson, Jessica R; Baum, Howard B A

    2016-01-01

    Medullary thyroid carcinoma (MTC) has been described as a source of ectopic ACTH secretion in patients with Cushing's syndrome. This is an infrequent association, occurring in less than 1% of MTC cases. Among these, it is even more unusual for an initial diagnosis of hypercortisolism to lead to the discovery of underlying MTC. Here we present a case of a patient with weakness, diarrhea, and hypokalemia who was found first to have Cushing's syndrome and later diagnosed with metastatic MTC. The patient was treated initially with oral agents to control his hypercortisolism, then with an etomidate infusion after experiencing intestinal perforation. He also received vandetanib therapy targeting his underlying malignancy, as this has been shown to reverse clinical signs of Cushing's syndrome in patients with MTC and subsequent ectopic ACTH secretion. Bilateral adrenalectomy was ultimately required. Medullary thyroid carcinoma should be considered in patients presenting with Cushing's syndrome due to ectopic ACTH secretion, and a multimodality treatment approach is often required. PMID:27141514

  20. [ACTH's ectopic secretion in a patient with precedents of Cushing's disease].

    PubMed

    Dal Verme, Agustín; Cejas, Carlos; Margan, Mercedes; Siguelboim, Daniel; Canosa, Victoria; Peralta, Christian

    2015-01-01

    A 54-year-old man, with a history of Cushing's disease diagnosed 32 years earlier, presented with edema, asthenia and general malaise. Abnormal laboratory studies depicted hypokalemia and metabolic alkalosis. A CT scan of the chest revealed a 3×3 cm tumor in the anterior mediastinum. The pathology was consistent with a thymic carcinoid. These findings led to a diagnosis of biochemical Cushing's syndrome secondary to ectopic secretion of ACTH. Thus, this patient suffered twice of Cushing's syndrome. The first instance was the consequence of an ACTH--secreting pituitary adenoma and the second of an ectopic secretion of ACTH. To the best of our knowledge this is the first such case reported in the medical literature.

  1. Synthetic ACTH in High Risk Patients with Idiopathic Membranous Nephropathy: A Prospective, Open Label Cohort Study

    PubMed Central

    van de Logt, Anne-Els; Beerenhout, Charles H.; Brink, Hans S.; van de Kerkhof, Jos J.; Wetzels, Jack F.; Hofstra, Julia M.

    2015-01-01

    New therapeutic agents are warranted in idiopathic membranous nephropathy. Synthetic ACTH may be advantageous with reported remission rates up to 85% and few side effects. We conducted a prospective open label cohort study from 2008 till 2010 (NCT00694863). We prospectively selected patients with idiopathic membranous nephropathy and high risk for progression (defined as βeta-2-microglobulin (β2m) excretion of >500 ng/min). For comparison, we selected matched historical controls treated with cyclophosphamide. The prospectively selected patients received intramuscular injections of synthetic ACTH during 9 months (maximal dose 1 mg twice a week). The primary endpoints concerned the feasibility and incidence of remissions as a primary event. Secondary endpoints included side effects of treatment and the incidence of remissions and relapses at long-term follow-up. Twenty patients (15 men) were included (age 54±14 years, serum creatinine 104 μmol/l [IQR 90–113], urine protein:creatinine ratio 8.7 g/10 mmol creatinine [IQR 4.3–11.1]). Seventeen patients (85%) completed treatment. 97% of injections were administered correctly. Cumulative remission rate was 55% (complete remission in 4 patients, partial remission 7 patients). In a group of historical controls treated with cyclophosphamide and steroids, 19 of 20 patients (95%) developed a remission (complete remission in 13 patients, partial remission in 6 patients) (p<0.01). The main limitation of our study is its small size and the use of a historical control group. We show that treatment with intramuscular injections of synthetic ACTH is feasible. Our data suggest that synthetic ACTH is less effective than cyclophosphamide in inducing a remission in high risk patients with idiopathic membranous nephropathy. The use of synthetic ACTH was also associated with many adverse events. Therefore, we advise against synthetic ACTH as standard treatment in membranous nephropathy. Trial Registration ClinicalTrials.gov NCT

  2. Vasopressin and angiotensin II in reflex regulation of ACTH, glucocorticoids, and renin: effect of water deprivation

    NASA Technical Reports Server (NTRS)

    Brooks, V. L.; Keil, L. C.

    1992-01-01

    Angiotensin II (ANG II) and vasopressin participate in baroreflex regulation of adrenocorticotropic hormone (ACTH), glucocorticoid, and renin secretion. The purpose of this study was to determine whether this participation is enhanced in water-deprived dogs, with chronically elevated plasma ANG II and vasopressin levels, compared with water-replete dogs. The baroreflex was assessed by infusing increasing doses of nitroprusside (0.3, 0.6, 1.5, and 3.0 micrograms.kg-1.min-1) in both groups of animals. To quantitate the participation of ANG II and vasopressin, the dogs were untreated or pretreated with the competitive ANG II antagonist saralasin, a V1-vasopressin antagonist, or combined V1/V2-vasopressin antagonist, either alone or in combination. The findings were as follows. 1) Larger reflex increases in ANG II, vasopressin, and glucocorticoids, but not ACTH, were produced in water-deprived dogs compared with water-replete dogs. 2) ANG II blockade blunted the glucocorticoid and ACTH responses to hypotension in water-deprived dogs, but not water-replete dogs. In contrast, vasopressin blockade reduced the ACTH response only in water-replete dogs. 3) Vasopressin or combined vasopressin and ANG II blockade reduced the plasma level of glucocorticoids related either to the fall in arterial pressure or to the increase in plasma ACTH concentration in water-replete dogs, and this effect was enhanced in water-deprived dogs. 4) In both water-deprived and water-replete animals, saralasin and/or a V1-antagonist increased the renin response to hypotension, but a combined V1/V2-antagonist did not. These results reemphasize the importance of endogenous ANG II and vasopressin in the regulation of ACTH, glucocorticoid, and renin secretion.(ABSTRACT TRUNCATED AT 250 WORDS).

  3. Modulation of adrenocorticotrophin hormone (ACTH)-induced expression of stress-related genes by PUFA in inter-renal cells from European sea bass (Dicentrarchus labrax).

    PubMed

    Montero, Daniel; Terova, Genciana; Rimoldi, Simona; Tort, Lluis; Negrin, Davinia; Zamorano, María Jesús; Izquierdo, Marisol

    2015-01-01

    Dietary fatty acids have been shown to exert a clear effect on the stress response, modulating the release of cortisol. The role of fatty acids on the expression of steroidogenic genes has been described in mammals, but little is known in fish. The effect of different fatty acids on the release of cortisol and expression of stress-related genes of European sea bass (Dicentrarchus labrax) head kidney, induced by a pulse of adenocorticotrophin hormone (ACTH), was studied. Tissue was maintained in superfusion with 60 min of incubation with EPA, DHA, arachidonic acid (ARA), linoleic acid or α-linolenic acid (ALA) during 490 min. Cortisol was measured by RIA. The quantification of stress-related genes transcripts was conducted by One-Step TaqMan real-time RT-PCR. There was an effect of the type of fatty acid on the ACTH-induced release of cortisol, values from ALA treatment being elevated within all of the experimental period. The expression of some steroidogenic genes, such as the steroidogenic acute regulatory protein (StAR) and c-fos, were affected by fatty acids, ALA increasing the expression of StAR after 1 h of ACTH stimulation whereas DHA, ARA and ALA increased the expression of c-fos after 20 min. ARA increased expression of the 11β-hydroxylase gene. Expression of heat shock protein 70 (HSP70) was increased in all the experimental treatments except for ARA. Results corroborate previous studies of the effect of different fatty acids on the release of cortisol in marine fish and demonstrate that those effects are mediated by alteration of the expression of steroidogenic genes.

  4. Test bed with force-measuring crank for static and dynamic investigations on cycling by means of functional electrical stimulation.

    PubMed

    Gföhler, M; Angeli, T; Eberharter, T; Lugner, P; Mayr, W; Hofer, C

    2001-06-01

    Cycling by means of functional electrical stimulation (FES) is an attractive training method for individuals with paraplegia. The physiological benefits of FES are combined with the psychological incentive of independent locomotion. In addition, cycling has the advantage in that the generated muscle forces are converted into drive power with relatively high efficiency compared to other means of locomotion, e.g., walking. For the design of an appropriate cycling device and the development of optimal stimulation patterns, it has to be investigated how the geometry for FES cycling, influenced by individual parameters of the FES-generated drive torques and the magnitude of variations among subjects with paraplegia, can be optimized. This study shows the design of a freely adjustable test bed with additional motor drive which allows static and dynamic measurements of force components and drive torque at the crank. Furthermore, the influence of geometry and various individual parameters on FES pedaling can be tested for each subject individually. A pedal path realized by a three-bar linkage that was optimized according to preliminary simulations further increases leg cycling efficiency. Safety precautions avoid injuries in case of excessive forces, e.g., spasms. Test results illustrate the application of the test bed and measurement routines. A test series with four paraplegic test persons showed that the presented static and dynamic measurement routines allow to provide optimal stimulation patterns for individual paraplegic subjects. While pedaling with these optimal stimulation patterns only negligible negative active drive torques, due to active muscle forces, were applied to the crank and sufficient drive power was generated to power a cycle independently.

  5. Test bed with force-measuring crank for static and dynamic investigations on cycling by means of functional electrical stimulation.

    PubMed

    Gföhler, M; Angeli, T; Eberharter, T; Lugner, P; Mayr, W; Hofer, C

    2001-06-01

    Cycling by means of functional electrical stimulation (FES) is an attractive training method for individuals with paraplegia. The physiological benefits of FES are combined with the psychological incentive of independent locomotion. In addition, cycling has the advantage in that the generated muscle forces are converted into drive power with relatively high efficiency compared to other means of locomotion, e.g., walking. For the design of an appropriate cycling device and the development of optimal stimulation patterns, it has to be investigated how the geometry for FES cycling, influenced by individual parameters of the FES-generated drive torques and the magnitude of variations among subjects with paraplegia, can be optimized. This study shows the design of a freely adjustable test bed with additional motor drive which allows static and dynamic measurements of force components and drive torque at the crank. Furthermore, the influence of geometry and various individual parameters on FES pedaling can be tested for each subject individually. A pedal path realized by a three-bar linkage that was optimized according to preliminary simulations further increases leg cycling efficiency. Safety precautions avoid injuries in case of excessive forces, e.g., spasms. Test results illustrate the application of the test bed and measurement routines. A test series with four paraplegic test persons showed that the presented static and dynamic measurement routines allow to provide optimal stimulation patterns for individual paraplegic subjects. While pedaling with these optimal stimulation patterns only negligible negative active drive torques, due to active muscle forces, were applied to the crank and sufficient drive power was generated to power a cycle independently. PMID:11474970

  6. Effect of low frequency stimulation on impaired spontaneous alternation behavior of kindled rats in Y-maze test.

    PubMed

    Ghafouri, Samireh; Fathollahi, Yaghoub; Javan, Mohammad; Shojaei, Amir; Asgari, Azam; Mirnajafi-Zadeh, Javad

    2016-10-01

    Epileptic seizures are characterized with cognitive disorders. In this study we investigated the effect of electrical low frequency stimulation (LFS), as a potential anticonvulsant agent, on kindled seizure-induced cognitive impairments. Animals were kindled through electrical stimulation of hippocampal CA1 area in a semi-rapid manner (12 stimulations/day). One group of animals received LFS 4 times at 0.5, 6.5, 24 and 30h following the last kindling stimulation. Applied LFS was consisted of 4 packages at 5min intervals. Each package contained 200 monophasic square wave pulses of 0.1ms duration at 1Hz. The Y-maze test was performed in all animals to measure the spontaneous alternation behavior. Kindled animals showed significant impairment in spontaneous alternation behavior compared to the control group. Application of LFS improved the observed impairment in spontaneous alternation behavior in kindled animals, so that there was no significant difference between kindled+LFS and control group. The observed improving effect of LFS was accompanied with a significant increase in calcineurin gene expression within the hippocampal area. Therefore, it may be postulated that application of LFS in kindled animals, which resulted in increment of calcineurin gene expression, can improve the seizure-induced impairment in spontaneous alternation behavior in Y-maze test.

  7. Lower birth weight and attenuated adrenocortical response to ACTH in offspring from sows that orally received cortisol during gestation.

    PubMed

    Kranendonk, Godelieve; Hopster, Hans; Fillerup, Maaike; Ekkel, E Dinand; Mulder, Eduard J H; Wiegant, Victor M; Taverne, Marcel A M

    2006-03-01

    Prenatal stress is known to affect several offspring characteristics, but its effects depend among other factors on the period of gestation in which it is applied. In the present study, oral administration of hydrocortisone-acetate (HCA) was used to elevate cortisol concentrations in pregnant sows to levels also observed after psychological stress. HCA was administered during three different periods of gestation (115 days in pigs): period 1: 21-50 (P1, n = 10), period 2: 51-80 (P2, n = 10) and period 3: 81-110 (P3, n = 10) days after insemination. Control sows (n = 11) received vehicle from 21-110 days after insemination. When P1-, P2- and P3-sows did not receive HCA, they also received vehicle. During gestation, weekly saliva samples were taken from the sows to determine salivary cortisol concentrations. Treatment effects on sow, litter and piglet characteristics were determined. In addition, two female piglets per litter were subjected to an ACTH-challenge test at 6 weeks of age to determine the adrenocortical response to ACTH. Pigs were slaughtered at 6 months of age and slaughter weight, back fat thickness and percentage of lean meat were analysed. During the period of treatment with HCA, salivary cortisol concentrations were increased in P1-, P2- and P3-sows compared to control sows (P < 0.01). The total number of piglets born per litter did not differ among treatment groups (P > 0.30), but pooled HCA-litters had a higher percentage of live born piglets (P < 0.05) and fewer mummies than control litters (P < 0.05). Gestation length did not differ among treatment groups (P = 0.21), but did affect treatment effects on birth weight. Overall, HCA-piglets weighed less at birth, and remained lighter until weaning (P < 0.05). The salivary cortisol concentrations after i.m. injection of ACTH (2.5 IU/kg) were lower in P1- and P3-piglets compared to control piglets. At slaughter, HCA-treatment indirectly decreased lean meat percentage and increased back fat thickness. In

  8. Language function and dysfunction among Chinese- and English-speaking polyglots: cortical stimulation, Wada testing, and clinical studies.

    PubMed

    Rapport, R L; Tan, C T; Whitaker, H A

    1983-03-01

    Language functions in a group of Chinese- and English-speaking polyglots living in a multiracial society have been investigated by several methods: the effects of cortical stimulation on object-naming and reading tasks in patients who required awake craniotomy, lateralization of cerebral dominance for speech by the Wada Test, and the pattern of language loss and recovery following stroke. The data indicate that these polyglots were all left hemisphere dominant for the languages tested: no consistent evidence for increased participation by the right hemisphere for language functions was found. The cortical stimulation experiments provided data most compatible with the "differential localization" model of cerebral localization in bilingualism. The variable which most influenced performance in all of these investigations was which language was used primarily for speaking as well as reading and writing at the time of the study. PMID:6188513

  9. Cortisol and ACTH plasma levels in maternal filicides and violent psychiatric women.

    PubMed

    Spironelli, Chiara; Gradante, Federica; Gradante, Giuseppe; Angrilli, Alessandro

    2013-05-01

    Maternal filicide may be considered the result of significant interactions between increased individual vulnerability and overwhelming environmental stress. The present study examined whether the biological vulnerability to stress and psychotic depression in criminally insane filicidal women was associated with an imbalance of stress-related hormones. Early-morning plasma levels of hormones associated with depression and chronic stress, i.e., thyroid hormones, Cortisol and Adrenocorticotropic hormone (ACTH), were measured in 10 filicidal inpatients recovered in a high-security psychiatric hospital for the criminally insane and 10 matched psychiatric, non-filicidal, criminal mothers with comparable traumatic/abuse records. Filicidal mothers had higher than normative Cortisol levels and significantly higher ACTH levels than both the normative values and plasma levels of non-filicidal women. Levels of thyroid hormones fell within normal ranges, without between-groups differences. In addition, while psychiatric controls had the expected Cortisol-ACTH positive correlation, mothers who killed their children revealed no relationship between the two hormones. HPA in the group of filicide perpetrators was altered despite they had received antidepressant pharmacological treatment. The observed imbalance of hypothalamic-pituitary-adrenal (HPA) axis indicates a possible filicides' reduced sensitivity of the adrenal glands to ACTH, probably due to the pre-hospitalization long-term affective stress which preceded child homicide. The results reveal the existence of large psycho-biological stress-sensitivity in filicides, and careful post-discharge psychiatric follow-up of such women is recommended. PMID:23375405

  10. Phase-Dependent Shifting of the Adrenal Clock by Acute Stress-Induced ACTH.

    PubMed

    Engeland, William C; Yoder, J Marina; Karsten, Carley A; Kofuji, Paulo

    2016-01-01

    The adrenal cortex has a molecular clock that generates circadian rhythms in glucocorticoid production, yet it is unclear how the clock responds to acute stress. We hypothesized that stress-induced ACTH provides a signal that phase shifts the adrenal clock. To assess whether acute stress phase shifts the adrenal clock in vivo in a phase-dependent manner, mPER2:LUC mice on a 12:12-h light:dark cycle underwent restraint stress for 15 min or no stress at zeitgeber time (ZT) 2 (early subjective day) or at ZT16 (early subjective night). Adrenal explants from mice stressed at ZT2 showed mPER2:LUC rhythms that were phase-advanced by ~2 h, whereas adrenals from mice stressed at ZT16 showed rhythms that were phase-delayed by ~2 h. The biphasic response was also observed in mice injected subcutaneously either with saline or with ACTH at ZT2 or ZT16. Blockade of the ACTH response with the glucocorticoid, dexamethasone, prevented restraint stress-induced phase shifts in the mPER2:LUC rhythm both at ZT2 and at ZT16. The finding that acute stress results in a phase-dependent shift in the adrenal mPER2:LUC rhythm that can be blocked by dexamethasone indicates that stress-induced effectors, including ACTH, act to phase shift the adrenal clock rhythm. PMID:27445984

  11. Short-term effects of ACTH on protein synthesis in adrenal cortex cells of young rats.

    PubMed

    Magalhães, M C; Magalhães, M M; Cimbra, A

    1975-11-19

    Two units of ACTH were administered intraperitoneally to young 20 gm-rats which received an intravenous injection of L-leucine-3H thirteen min later. ACTH-injected rats, and control rats which received the isotope alone, were killed at 2-, 10-, 30- and 60-min intervals. Electron microscope autoradiographs in control animals showed strong amino-acid uptake at pulse time (2-min) in the cytoplasm of adrenal zona fasciculata cells. Label was shared between the endoplasmic reticulum (ER) and mitochondria, and a lower but still considerable uptake was seen in nucleoli. At first chase time interval (10-min) cytoplasmic labelling declined, while nuclear and nucleolar labelling increased, both changing little thereafter, and there was a 10-30 min Golgi peak. ACTH administration provoked an overall increase in amino-acid incorporation into cytoplasm, nucleus and nucleolus at pulse time, with no changes in the distribution of the reactions among organelles. Intensification of labelling was most evident over nucleoli, the grain density of which was four-times as high as in controls. The short-term increase in ER and mitochondrial protein synthesis observed after ACTH injections was considered to be consistent with the hypothesis that most newly-formed proteins in these cells may be involved in the regulation of steroidogenesis. The marked increase in nucleolar labelling suggested the presence of proteins involved in RNA synthesis.

  12. Phase-Dependent Shifting of the Adrenal Clock by Acute Stress-Induced ACTH

    PubMed Central

    Engeland, William C.; Yoder, J. Marina; Karsten, Carley A.; Kofuji, Paulo

    2016-01-01

    The adrenal cortex has a molecular clock that generates circadian rhythms in glucocorticoid production, yet it is unclear how the clock responds to acute stress. We hypothesized that stress-induced ACTH provides a signal that phase shifts the adrenal clock. To assess whether acute stress phase shifts the adrenal clock in vivo in a phase-dependent manner, mPER2:LUC mice on a 12:12-h light:dark cycle underwent restraint stress for 15 min or no stress at zeitgeber time (ZT) 2 (early subjective day) or at ZT16 (early subjective night). Adrenal explants from mice stressed at ZT2 showed mPER2:LUC rhythms that were phase-advanced by ~2 h, whereas adrenals from mice stressed at ZT16 showed rhythms that were phase-delayed by ~2 h. The biphasic response was also observed in mice injected subcutaneously either with saline or with ACTH at ZT2 or ZT16. Blockade of the ACTH response with the glucocorticoid, dexamethasone, prevented restraint stress-induced phase shifts in the mPER2:LUC rhythm both at ZT2 and at ZT16. The finding that acute stress results in a phase-dependent shift in the adrenal mPER2:LUC rhythm that can be blocked by dexamethasone indicates that stress-induced effectors, including ACTH, act to phase shift the adrenal clock rhythm. PMID:27445984

  13. Double Stimulation in the Waiting Experiment with Collectives: Testing a Vygotskian Model of the Emergence of Volitional Action.

    PubMed

    Sannino, Annalisa

    2016-03-01

    This study explores what human conduct looks like when research embraces uncertainty and distance itself from the dominant methodological demands of control and predictability. The context is the waiting experiment originally designed in Kurt Lewin's research group, discussed by Vygotsky as an instance among a range of experiments related to his notion of double stimulation. Little attention has been paid to this experiment, despite its great heuristic potential for charting the terrain of uncertainty and agency in experimental settings. Behind the notion of double stimulation lays Vygotsky's distinctive view of human beings' ability to intentionally shape their actions. Accordingly, human beings in situations of uncertainty and cognitive incongruity can rely on artifacts which serve the function of auxiliary motives and which help them undertake volitional actions. A double stimulation model depicting how such actions emerge is tested in a waiting experiment conducted with collectives, in contrast with a previous waiting experiment conducted with individuals. The model, validated in the waiting experiment with individual participants, applies only to a limited extent to the collectives. The analysis shows the extent to which double stimulation takes place in the waiting experiment with collectives, the differences between the two experiments, and what implications can be drawn for an expanded view on experiments.

  14. Double Stimulation in the Waiting Experiment with Collectives: Testing a Vygotskian Model of the Emergence of Volitional Action.

    PubMed

    Sannino, Annalisa

    2016-03-01

    This study explores what human conduct looks like when research embraces uncertainty and distance itself from the dominant methodological demands of control and predictability. The context is the waiting experiment originally designed in Kurt Lewin's research group, discussed by Vygotsky as an instance among a range of experiments related to his notion of double stimulation. Little attention has been paid to this experiment, despite its great heuristic potential for charting the terrain of uncertainty and agency in experimental settings. Behind the notion of double stimulation lays Vygotsky's distinctive view of human beings' ability to intentionally shape their actions. Accordingly, human beings in situations of uncertainty and cognitive incongruity can rely on artifacts which serve the function of auxiliary motives and which help them undertake volitional actions. A double stimulation model depicting how such actions emerge is tested in a waiting experiment conducted with collectives, in contrast with a previous waiting experiment conducted with individuals. The model, validated in the waiting experiment with individual participants, applies only to a limited extent to the collectives. The analysis shows the extent to which double stimulation takes place in the waiting experiment with collectives, the differences between the two experiments, and what implications can be drawn for an expanded view on experiments. PMID:26318436

  15. Reappraisal of bovril as a source of arginine in the arginine stimulation test for growth hormone deficiency.

    PubMed

    Loh, H H; Norlela, S; Nor Azmi, K

    2015-06-01

    The purpose of this case study is to report the use of oral Bovril (a food supplement which contains arginine) as an alternative test for growth hormone stimulation test. We performed oral Bovril test in 3 patients -- one with suspected growth hormone deficiency in whom insulin tolerance test could not be performed (subject A), one sex-matched control (subject B), and one with confirmed growth hormone deficiency (subject C). 14g/m(2) of oral Bovril was mixed with 150ml of warm water and was given to all three subjects. Blood for growth hormone was taken at baseline, and every 30 minutes till 150 minutes after ingestion of oral Bovril. The ingestion of oral Bovril showed a positive response in subjects A and B, with highest growth hormone levels of 28.4mIU/L and 42.0mIU/L respectively at 150 minutes. Subject C had suppressed growth hormone throughout the test. Oral Bovril is readily available and is a safe alternative for standard growth hormone stimulation test. PMID:26248787

  16. Chlorotriazine herbicides and metabolites activate an ACTH-dependent release of corticosterone in male Wistar rats.

    PubMed

    Laws, Susan C; Hotchkiss, Michelle; Ferrell, Janet; Jayaraman, Saro; Mills, Lesley; Modic, Walker; Tinfo, Nicole; Fraites, Melanie; Stoker, Tammy; Cooper, Ralph

    2009-11-01

    Previously, we reported that atrazine (ATR) alters steroidogenesis in male Wistar rats resulting in elevated serum corticosterone (CORT), progesterone, and estrogens. The increase in CORT indicated that this chlorotriazine herbicide may alter the hypothalamic-pituitary-adrenal axis. This study characterizes the temporal changes in adrenocorticotropic hormone (ACTH), CORT, and P4 in male Wistar rats following a single dose of ATR (0, 5, 50, 100, and 200 mg/kg), simazine (SIM; 188 mg/kg), propazine (PRO; 213 mg/kg), or primary metabolites, deisopropylatrazine (DIA; 4, 10, 40, 80, and 160 mg/kg), deethylatrazine (DEA; 173 mg/kg), and diamino-s-chlorotriazine (DACT; 3.37, 33.7, 67.5, and 135 mg/kg). The maximum dose for each chemical was the molar equivalent of ATR (200 mg/kg). Significant increases in plasma ACTH were observed within 15 min, following exposure to ATR, SIM, PRO, DIA, or DEA. Dose-dependent elevations in CORT and progesterone were also observed at 15 and 30 min post-dosing with these compounds indicating an activation of adrenal steroidogenesis. Measurement of the plasma concentrations of the parent compounds and metabolites confirmed that ATR, SIM, and PRO are rapidly metabolized to DACT. Although DACT had only minimal effects on ACTH and steroid release, dosing with this metabolite resulted in plasma DACT concentrations that were 60-fold greater than that observed following an equimolar dose of ATR and eightfold greater than equimolar doses of DIA or DEA, indicating that DACT is not likely the primary inducer of ACTH release. Thus, the rapid release of ACTH and subsequent activation of adrenal steroidogenesis following a single exposure to ATR, SIM, PRO, DIA, or DEA may reflect chlorotriazine-induced changes at the level of the brain and/or pituitary.

  17. Transcranial direct current stimulation (tDCS) of frontal cortex decreases performance on the WAIS-IV intelligence test.

    PubMed

    Sellers, Kristin K; Mellin, Juliann M; Lustenberger, Caroline M; Boyle, Michael R; Lee, Won Hee; Peterchev, Angel V; Fröhlich, Flavio

    2015-09-01

    Transcranial direct current stimulation (tDCS) modulates excitability of motor cortex. However, there is conflicting evidence about the efficacy of this non-invasive brain stimulation modality to modulate performance on cognitive tasks. Previous work has tested the effect of tDCS on specific facets of cognition and executive processing. However, no randomized, double-blind, sham-controlled study has looked at the effects of tDCS on a comprehensive battery of cognitive processes. The objective of this study was to test if tDCS had an effect on performance on a comprehensive assay of cognitive processes, a standardized intelligence quotient (IQ) test. The study consisted of two substudies and followed a double-blind, between-subjects, sham-controlled design. In total, 41 healthy adult participants were included in the final analysis. These participants completed the Wechsler Adult Intelligence Scale, Fourth Edition (WAIS-IV) as a baseline measure. At least one week later, participants in substudy 1 received either bilateral tDCS (anodes over both F4 and F3, cathode over Cz, 2 mA at each anode for 20 min) or active sham tDCS (2 mA for 40 s), and participants in substudy 2 received either right or left tDCS (anode over either F4 or F3, cathode over Cz, 2 mA for 20 min). In both studies, the WAIS-IV was immediately administered following stimulation to assess for performance differences induced by bilateral and unilateral tDCS. Compared to sham stimulation, right, left, and bilateral tDCS reduced improvement between sessions on Full Scale IQ and the Perceptual Reasoning Index. This demonstration that frontal tDCS selectively degraded improvement on specific metrics of the WAIS-IV raises important questions about the often proposed role of tDCS in cognitive enhancement.

  18. Stimulation from Cochlear Implant Electrodes Assists with Recovery from Asymmetric Perceptual Tilt: Evidence from the Subjective Visual Vertical Test.

    PubMed

    Gnanasegaram, Joshua J; Parkes, William J; Cushing, Sharon L; McKnight, Carmen L; Papsin, Blake C; Gordon, Karen A

    2016-01-01

    Vestibular end organ impairment is highly prevalent in children who have sensorineural hearing loss (SNHL) rehabilitated with cochlear implants (CIs). As a result, spatial perception is likely to be impacted in this population. Of particular interest is the perception of visual vertical because it reflects a perceptual tilt in the roll axis and is sensitive to an imbalance in otolith function. The objectives of the present study were thus to identify abnormalities in perception of the vertical plane in children with SNHL and determine whether such abnormalities could be resolved with stimulation from the CI. Participants included 53 children (15.2 ± 4.0 years of age) with SNHL and vestibular loss, confirmed with vestibular evoked myogenic potential (VEMP) testing. Testing protocol was validated in a sample of nine young adults with normal hearing (28.8 ± 7.7 years). Perception of visual vertical was assessed using the static Subjective Visual Vertical (SVV) test performed with and without stimulation in the participants with cochleovestibular loss. Trains of electrical pulses were delivered by an electrode in the left and/or right ear. Asymmetric spatial orientation deficits were found in nearly half of the participants with CIs (24/53 [45%]). The abnormal perception in this cohort was exacerbated by visual tilts in the direction of their deficit. Electric pulse trains delivered using the CI shifted this abnormal perception towards center (i.e., normal; p = 0.007). Importantly, this benefit was realized regardless of which ear was stimulated. These results suggest a role for CI stimulation beyond the auditory system, in particular, for improving vestibular/balance function. PMID:27679562

  19. Stimulation from Cochlear Implant Electrodes Assists with Recovery from Asymmetric Perceptual Tilt: Evidence from the Subjective Visual Vertical Test

    PubMed Central

    Gnanasegaram, Joshua J.; Parkes, William J.; Cushing, Sharon L.; McKnight, Carmen L.; Papsin, Blake C.; Gordon, Karen A.

    2016-01-01

    Vestibular end organ impairment is highly prevalent in children who have sensorineural hearing loss (SNHL) rehabilitated with cochlear implants (CIs). As a result, spatial perception is likely to be impacted in this population. Of particular interest is the perception of visual vertical because it reflects a perceptual tilt in the roll axis and is sensitive to an imbalance in otolith function. The objectives of the present study were thus to identify abnormalities in perception of the vertical plane in children with SNHL and determine whether such abnormalities could be resolved with stimulation from the CI. Participants included 53 children (15.2 ± 4.0 years of age) with SNHL and vestibular loss, confirmed with vestibular evoked myogenic potential (VEMP) testing. Testing protocol was validated in a sample of nine young adults with normal hearing (28.8 ± 7.7 years). Perception of visual vertical was assessed using the static Subjective Visual Vertical (SVV) test performed with and without stimulation in the participants with cochleovestibular loss. Trains of electrical pulses were delivered by an electrode in the left and/or right ear. Asymmetric spatial orientation deficits were found in nearly half of the participants with CIs (24/53 [45%]). The abnormal perception in this cohort was exacerbated by visual tilts in the direction of their deficit. Electric pulse trains delivered using the CI shifted this abnormal perception towards center (i.e., normal; p = 0.007). Importantly, this benefit was realized regardless of which ear was stimulated. These results suggest a role for CI stimulation beyond the auditory system, in particular, for improving vestibular/balance function. PMID:27679562

  20. Transcranial direct current stimulation (tDCS) of frontal cortex decreases performance on the WAIS-IV intelligence test.

    PubMed

    Sellers, Kristin K; Mellin, Juliann M; Lustenberger, Caroline M; Boyle, Michael R; Lee, Won Hee; Peterchev, Angel V; Fröhlich, Flavio

    2015-09-01

    Transcranial direct current stimulation (tDCS) modulates excitability of motor cortex. However, there is conflicting evidence about the efficacy of this non-invasive brain stimulation modality to modulate performance on cognitive tasks. Previous work has tested the effect of tDCS on specific facets of cognition and executive processing. However, no randomized, double-blind, sham-controlled study has looked at the effects of tDCS on a comprehensive battery of cognitive processes. The objective of this study was to test if tDCS had an effect on performance on a comprehensive assay of cognitive processes, a standardized intelligence quotient (IQ) test. The study consisted of two substudies and followed a double-blind, between-subjects, sham-controlled design. In total, 41 healthy adult participants were included in the final analysis. These participants completed the Wechsler Adult Intelligence Scale, Fourth Edition (WAIS-IV) as a baseline measure. At least one week later, participants in substudy 1 received either bilateral tDCS (anodes over both F4 and F3, cathode over Cz, 2 mA at each anode for 20 min) or active sham tDCS (2 mA for 40 s), and participants in substudy 2 received either right or left tDCS (anode over either F4 or F3, cathode over Cz, 2 mA for 20 min). In both studies, the WAIS-IV was immediately administered following stimulation to assess for performance differences induced by bilateral and unilateral tDCS. Compared to sham stimulation, right, left, and bilateral tDCS reduced improvement between sessions on Full Scale IQ and the Perceptual Reasoning Index. This demonstration that frontal tDCS selectively degraded improvement on specific metrics of the WAIS-IV raises important questions about the often proposed role of tDCS in cognitive enhancement. PMID:25934490

  1. Stimulation from Cochlear Implant Electrodes Assists with Recovery from Asymmetric Perceptual Tilt: Evidence from the Subjective Visual Vertical Test

    PubMed Central

    Gnanasegaram, Joshua J.; Parkes, William J.; Cushing, Sharon L.; McKnight, Carmen L.; Papsin, Blake C.; Gordon, Karen A.

    2016-01-01

    Vestibular end organ impairment is highly prevalent in children who have sensorineural hearing loss (SNHL) rehabilitated with cochlear implants (CIs). As a result, spatial perception is likely to be impacted in this population. Of particular interest is the perception of visual vertical because it reflects a perceptual tilt in the roll axis and is sensitive to an imbalance in otolith function. The objectives of the present study were thus to identify abnormalities in perception of the vertical plane in children with SNHL and determine whether such abnormalities could be resolved with stimulation from the CI. Participants included 53 children (15.2 ± 4.0 years of age) with SNHL and vestibular loss, confirmed with vestibular evoked myogenic potential (VEMP) testing. Testing protocol was validated in a sample of nine young adults with normal hearing (28.8 ± 7.7 years). Perception of visual vertical was assessed using the static Subjective Visual Vertical (SVV) test performed with and without stimulation in the participants with cochleovestibular loss. Trains of electrical pulses were delivered by an electrode in the left and/or right ear. Asymmetric spatial orientation deficits were found in nearly half of the participants with CIs (24/53 [45%]). The abnormal perception in this cohort was exacerbated by visual tilts in the direction of their deficit. Electric pulse trains delivered using the CI shifted this abnormal perception towards center (i.e., normal; p = 0.007). Importantly, this benefit was realized regardless of which ear was stimulated. These results suggest a role for CI stimulation beyond the auditory system, in particular, for improving vestibular/balance function.

  2. Testing different paradigms to optimize antidepressant deep brain stimulation in different rat models of depression.

    PubMed

    Rummel, Julia; Voget, Mareike; Hadar, Ravit; Ewing, Samuel; Sohr, Reinhard; Klein, Julia; Sartorius, Alexander; Heinz, Andreas; Mathé, Aleksander A; Vollmayr, Barbara; Winter, Christine

    2016-10-01

    Deep brain stimulation (DBS) of several targets induces beneficial responses in approximately 60% of patients suffering from treatment-resistant depression (TRD). The remaining 40% indicate that these stimulation sites do not bear therapeutic relevance for all TRD patients and consequently DBS-targets should be selected according to individual symptom profiles. We here used two animal models of depression known to have different genetic backgrounds and behavioral responses: the therapy-responsive Flinders sensitive line (FSL) and the therapy-refractory congenitally learned helpless rats (cLH) to study symptom-specific DBS effects i) of different brain sites ii) at different stimulation parameters, and iii) at different expressions of the disease. Sham-stimulation/DBS was applied chronic-intermittently or chronic-continuously to either the ventromedial prefrontal cortex (vmPFC, rodent equivalent to subgenual cingulate), nucleus accumbens (Nacc) or subthalamic nucleus (STN), and effects were studied on different depression-associated behaviors, i.e. anhedonia, immobility/behavioral despair and learned helplessness. Biochemical substrates of behaviorally effective versus ineffective DBS were analyzed using in-vivo microdialysis and post-mortem high-performance liquid chromatography (HPLC). We found that i) vmPFC-DBS outperforms Nacc-DBS, ii) STN-DBS increases depressive states, iii) chronic-continuous DBS does not add benefits compared to chronic-intermittent DBS, iv) DBS-efficacy depends on the disease expression modeled and iv) antidepressant DBS is associated with an increase in serotonin turnover alongside site-specific reductions in serotonin contents. The reported limited effectiveness of vmPFC DBS suggests that future research may consider the specific disease expression, investigation of different DBS-targets and alternative parameter settings.

  3. Testing different paradigms to optimize antidepressant deep brain stimulation in different rat models of depression.

    PubMed

    Rummel, Julia; Voget, Mareike; Hadar, Ravit; Ewing, Samuel; Sohr, Reinhard; Klein, Julia; Sartorius, Alexander; Heinz, Andreas; Mathé, Aleksander A; Vollmayr, Barbara; Winter, Christine

    2016-10-01

    Deep brain stimulation (DBS) of several targets induces beneficial responses in approximately 60% of patients suffering from treatment-resistant depression (TRD). The remaining 40% indicate that these stimulation sites do not bear therapeutic relevance for all TRD patients and consequently DBS-targets should be selected according to individual symptom profiles. We here used two animal models of depression known to have different genetic backgrounds and behavioral responses: the therapy-responsive Flinders sensitive line (FSL) and the therapy-refractory congenitally learned helpless rats (cLH) to study symptom-specific DBS effects i) of different brain sites ii) at different stimulation parameters, and iii) at different expressions of the disease. Sham-stimulation/DBS was applied chronic-intermittently or chronic-continuously to either the ventromedial prefrontal cortex (vmPFC, rodent equivalent to subgenual cingulate), nucleus accumbens (Nacc) or subthalamic nucleus (STN), and effects were studied on different depression-associated behaviors, i.e. anhedonia, immobility/behavioral despair and learned helplessness. Biochemical substrates of behaviorally effective versus ineffective DBS were analyzed using in-vivo microdialysis and post-mortem high-performance liquid chromatography (HPLC). We found that i) vmPFC-DBS outperforms Nacc-DBS, ii) STN-DBS increases depressive states, iii) chronic-continuous DBS does not add benefits compared to chronic-intermittent DBS, iv) DBS-efficacy depends on the disease expression modeled and iv) antidepressant DBS is associated with an increase in serotonin turnover alongside site-specific reductions in serotonin contents. The reported limited effectiveness of vmPFC DBS suggests that future research may consider the specific disease expression, investigation of different DBS-targets and alternative parameter settings. PMID:27367210

  4. Severe hypokalemia, metabolic alkalosis and hypertension in a 54 year old male with ectopic ACTH syndrome: a case report.

    PubMed

    Martínez-Valles, Miguel Angel; Palafox-Cazarez, Asael; Paredes-Avina, Jose Antonio

    2009-01-01

    Ectopic ACTH syndrome is a rare cause of Cushing's syndrome accounting for about 15% of all cases. Small cell lung cancer and bronchial carcinoids account for about half of the cases. Malignant neoplasm has rapid and more aggressive metabolic effects. We report a 54-year-old male patient with phenotypic features of Cushing's syndrome with severe hypokalemia, metabolic alkalosis, hypertension and altered mental status as manifestations of an ACTH-secreting small cell carcinoma from the lung. Ectopic ACTH syndrome should be highly considered in patients with hypertension and severe hypokalemic metabolic alkalosis, especially when a lung mass is discovered. PMID:19829770

  5. Severe hypokalemia, metabolic alkalosis and hypertension in a 54 year old male with ectopic ACTH syndrome: a case report

    PubMed Central

    Palafox-Cazarez, Asael; Paredes-Avina, Jose Antonio

    2009-01-01

    Ectopic ACTH syndrome is a rare cause of Cushing’s syndrome accounting for about 15% of all cases. Small cell lung cancer and bronchial carcinoids account for about half of the cases. Malignant neoplasm has rapid and more aggressive metabolic effects. We report a 54-year-old male patient with phenotypic features of Cushing’s syndrome with severe hypokalemia, metabolic alkalosis, hypertension and altered mental status as manifestations of an ACTH-secreting small cell carcinoma from the lung. Ectopic ACTH syndrome should be highly considered in patients with hypertension and severe hypokalemic metabolic alkalosis, especially when a lung mass is discovered. PMID:19829770

  6. Single-Session CT-Guided Percutaneous Microwave Ablation of Bilateral Adrenal Gland Hyperplasia Due to Ectopic ACTH Syndrome.

    PubMed

    Sarma, Asha; Shyn, Paul B; Vivian, Mark A; Ng, Ju-Mei; Tuncali, Kemal; Lorch, Jorchen H; Zaheer, Sarah N; Gordon, Michael S; Silverman, Stuart G

    2015-10-01

    Bilateral adrenalectomy is currently the only available treatment for adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome (ectopic ACTH syndrome) that is refractory to pharmacologic therapy. We describe two patients with refractory ectopic ACTH syndrome who were treated with CT-guided percutaneous microwave ablation of both hyperplastic adrenal glands in a single session: O ne was not a surgical candidate, and the other had undergone unsuccessful surgery. Following the procedure, both patients achieved substantial decreases in serum cortisol, symptomatic improvement, and decreased anti-hypertensive medication requirements.

  7. Single-Session CT-Guided Percutaneous Microwave Ablation of Bilateral Adrenal Gland Hyperplasia Due to Ectopic ACTH Syndrome

    SciTech Connect

    Sarma, Asha Shyn, Paul B.; Vivian, Mark A.; Ng, Ju-Mei; Tuncali, Kemal; Lorch, Jorchen H.; Zaheer, Sarah N.; Gordon, Michael S.; Silverman, Stuart G.

    2015-10-15

    Bilateral adrenalectomy is currently the only available treatment for adrenocorticotropic hormone (ACTH)-dependent Cushing’s syndrome (ectopic ACTH syndrome) that is refractory to pharmacologic therapy. We describe two patients with refractory ectopic ACTH syndrome who were treated with CT-guided percutaneous microwave ablation of both hyperplastic adrenal glands in a single session: One was not a surgical candidate, and the other had undergone unsuccessful surgery. Following the procedure, both patients achieved substantial decreases in serum cortisol, symptomatic improvement, and decreased anti-hypertensive medication requirements.

  8. Cortisol and ACTH response to oral dexamethasone in obesity and effects of sex, body fat distribution, and dexamethasone concentrations: a dose-response study.

    PubMed

    Pasquali, Renato; Ambrosi, Bruno; Armanini, Decio; Cavagnini, Francesco; Uberti, Ettore Degli; Del Rio, Graziano; de Pergola, Giovanni; Maccario, Mauro; Mantero, Franco; Marugo, Mario; Rotella, Carlo Maria; Vettor, Roberto

    2002-01-01

    There is increasing evidence that the abdominal obesity phenotype may be associated with multiple alterations of the hypothalamic-pituitary-adrenocortical (HPA) axis activity in both sexes. Our hypothesis is that the lack of adequate cortisol suppression after the dexamethasone test may constitute an indirect marker of HPA axis hyperactivity in the presence of the abdominal obesity phenotype. A total of 34 normal-weight (13 men and 21 women) and 87 obese (36 men and 51 women), healthy, nondepressed subjects therefore underwent four different dexamethasone suppression tests randomly performed at varying intervals of at least 1 wk between each test. After a standard overnight 1-mg dexamethasone test, which served as a reference, three other tests were randomly performed at 1-wk intervals by administering 0.0035, 0.0070, and 0.015 mg oral dexamethasone per kilogram of body weight overnight. Blood samples were obtained for cortisol, ACTH, and dexamethasone. Results were analyzed separately in men and women as well as in normal-weight [body mass index (BMI) < or = 25 kg/m(2)] and overweight or obese (BMI > 25 kg/m(2)) subjects. The waist circumference and the waist to hip ratio (WHR) were used as markers of body fat distribution. After the standard 1-mg test, cortisol suppression was greater than 90% in all subjects. However, after each test, obese women had significantly higher values of percent cortisol and percent ACTH suppression than normal-weight women without any difference between obese and normal-weight men. Considering the response to the three variable-dose tests, a clear dose- response pattern (P < 0.001 for trend analysis) in percent cortisol and percent ACTH suppression was found in all subjects. After each test men had significantly higher dexamethasone levels than women, regardless of BMI. However, obese women, but not men, had significantly higher dexamethasone levels after each test than their normal-weight counterpart. Plasma dexamethasone

  9. Reservoir Stimulation Experiments at the Grimsel Test Site: Stress Measurements using Hydraulic fracturing, Hydraulic Tests on Pre-existing Fractures and Overcoring

    NASA Astrophysics Data System (ADS)

    Doetsch, J.; Gischig, V.; Amann, F.; Madonna, C.; Jalali, M.; Valley, B.; Evans, K. F.

    2015-12-01

    A decameter-scale in-situ hydraulic stimulation and circulation experiment has been planned in the Deep Underground rock Laboratory (DUG Lab) at the Grimsel Test Site, Switzerland. The general objective of this experiment is to improve our understanding of the pressure, temperature and stress changes in the rock mass due to hydraulic stimulation. In this context, the main goal is to investigate the effect of hydro-shearing on the local stress variation as well as transient and permanent permeability changes with comprehensive thermo-hydro-mechanical (THM) and acoustic emission monitoring. This experiment is designed such that stimulation processes are recorded in a dataset that is unique in THM coupled processes and induced seismicity research. In preparation to the hydro-shearing experiments, the experimental rock volume has been studied in detail using geological tunnel mapping, optical televiewer in existing boreholes, hydraulic tests, geophysical imaging and review of the extensive literature on experiments at the Grimsel Test Site. The geophysical investigations include reflection and transmission ground penetrating radar (GPR) and seismic measurements between the tunnels to image shear zones and reveal heterogeneity of the rock mass. The orientation and magnitude of the principal stresses of the rock volume and its surroundings has been analyzed using hydraulic fracturing, hydraulic tests on pre-existing fractures and overcoring. The hydraulic fracturing tests for stress measurements were monitored using a 32-channel acoustic emission monitoring system and a regional seismic monitoring network. Here, we present the results of the pre-investigations and stress measurements, and give an outlook for the hydro-shearing experiments planned for spring 2016.

  10. Transcription of (pro)renin mRNA in the rat adrenal cortex, and the effects of ACTH treatment and a low sodium diet.

    PubMed

    Ho, M M; Vinson, G P

    1998-05-01

    Transcription of the (pro)renin gene in the adult rat adrenal gland was studied by non-isotopic in situ hybridization. In glands from control (untreated) animals, transcription was relatively sparse, and occurred mostly in the outer zona fasciculata. Treatment with ACTH increased the apparent signal in both the glomerulosa and in fasciculata zones. A low sodium diet initially enhanced the transcription signal specifically in the glomerulosa, but as the regime was extended from 5 days to more than 2 weeks, the signal was also increased dramatically in the zona reticularis. The results emphasize the potential importance of the intraglandular renin-angiotensin system, particularly under conditions of chronic stimulation. They also suggest that angiotensin II, as well as being the major regulator of the glomerulosa, may also have some role in inner adrenocortical zone functions.

  11. Non-destructive testing of works of art by stimulated infrared thermography

    NASA Astrophysics Data System (ADS)

    Candoré, J. C.; Bodnar, J. L.; Detalle, V.; Grossel, P.

    2012-02-01

    In this work, we present various examples of assistance to the restoration of works of art by stimulated infrared thermography. We show initially that the method allows the detection of delamination located in mural paintings, such as in the "Saint Christophe" of the Campana collection of the Louvre French museum. We show then that it also makes it possible to detect delaminations or galleries of worms in marquetries. We show in a third stage that it provides for the detection of detachment of grayness in stained glasses. We show in a fourth stage that it allows the visualization of shards or metal inserts located in a Greek "panathénaque" amphora of the French National museum of the Ceramics of Sevres. We show finally, that the method permits the detection of a crack located in an ovoid vase of the same French National museum of the Ceramics of Sevres.

  12. Effects of ACTH on corticosteroid and progesterone levels in female baboons depending on the phase of the menstrual cycle

    SciTech Connect

    Todua, T.N.; Goncharov, N.P.; Katsiya, G.V.; Lapin, B.A.; Vorontsov, V.I.

    1986-01-01

    To study the effect of ACTH on the endocrine function of steroid producing glands depending on the level of sex hormones in the body, a comparative study of the dynamics of steroid hormones in the follicular and luteal phases of the menstrual cycle in response to a standard does of ACTH was undertaken in experiments on hamadryad baboons. Concentrations of corticosterone, 11-deoxycortisol, and progesterone were determined in duplicate samples of plasma by radioimmunoassay. It is shown that the sensitivity of the adrenals to a single injection of ACTH is independent of the phase of the menstrual cycle and the inhibitory effects of ACTH on progesterone secretion is exhibited only in the presence of an actively functioning corpus luteus of the ovary.

  13. Comparative stereological studies on the effects of long term CRF and ACTH treatment on the cortex of the suprarenal gland.

    PubMed

    Miśkowiak, B; Kasprzak, A; Malendowicz, L K

    1986-06-01

    The aim of the study was to investigate by means of stereological and biochemical methods the effects of long-term CRF administration on the cortex of the suprarenal gland of adult male rats and to compare these effects with those of ACTH. Both CRF (administered into the lateral ventricle of the brain) and ACTH resulted after 8 days in an increase in weight of the suprarenal gland. Both treatments increased the volume of individual adrenocortical zones and the average volume of adrenocortical cells as well as enhancing the total number of parenchymal cells in the paired glands. There was also no significant difference in those functional parameters studied of the adrenocortical cells of CRF- and ACTH-treated rats. Thus, long term treatment of adult male rats with CRF evoked adrenocortical changes similar to those observed after ACTH administration.

  14. Small-cell Lung Cancer in a Young Adult Nonsmoking Patient with Ectopic Adrenocorticotropin (ACTH) Production.

    PubMed

    Aoki, Masahiko; Fujisaka, Yasuhito; Tokioka, Satoshi; Hirai, Ai; Henmi, Yujiro; Inoue, Yosuke; Narabayashi, Ken; Yamano, Takeshi; Tamura, Yosuke; Egashira, Yutaro; Higuchi, Kazuhide

    2016-01-01

    Cushing's syndrome due to young small-cell lung cancer (SCLC) is recognized as being extremely rare. We herein present the case of a 35-year-old nonsmoking man who presented with thirst and polyuria. Laboratory examinations showed hyperglycemia, hypokalemia and liver enzyme elevation. Imaging examinations revealed the presence of multiple liver tumors and lymph node swelling. The levels of serum neuroendocrine tumor markers were elevated. The patient was diagnosed with SCLC based on the pathological examination of a biopsy specimen from the right supraclavicular lymph node. The physical findings, including proximal myopathy, truncal obesity and pigmentation suggested high levels of glucocorticoids. An immunohistochemical examination of the tumor showed that it was positive for adrenocorticotropin (ACTH). An endocrinological investigation allowed for the definitive diagnosis of SCLC with ectopic ACTH production. PMID:27181543

  15. Effect of deafferentation of the rat tongue on plasma corticosterone, aldosterone, angiotensin and ACTH levels

    SciTech Connect

    Polyntsev, Yu.V.; Serova, O.N.

    1987-09-01

    The effect of deafferentation of the tongue on the plasma level of hormones involved in regulation of the sodium ion level -- aldosterone, corticosterone, ACTH, and angiotensin -- was studied. Plasma hormone levels were determined by radioimmunoassay. The results indicate the important role of orosensory and taste perception in the processes of regulation of the sodium balance in the body. The experiments in this study were conducted on rats.

  16. Medullary nephrocalcinosis and pancreatic calcifications demonstrated by ultrasound and CT in infants after treatment with ACTH

    SciTech Connect

    Rausch, H.P.; Hanefield, F.; Kaufmann, B.J.

    1984-10-01

    Thirteen patients who had undergone prolonged adrenocorticotropic hormone (ACTH) therapy for infantile spasms or encephalopathy were examined with sonography. Nine patients were seen to have appearances characteristic of medullary nephrocalcinosis. Five patients also showed a homogeneously increased echogenicity of the whole pancreas on sonography, and one of these showed increased density on computed tomography. Density measurements were in the range of calcific arterial within the papillae and pancreatic tissue. On abdominal survey radiographs, even in retrospect, no calcifications could be recognized.

  17. Effects of ACTH, capture, and short term confinement on glucocorticoid concentrations in harlequin ducks (Histrionicus histrionicus)

    USGS Publications Warehouse

    Nilsson, P.B.; Hollmén, Tuula E.; Atkinson, S.; Mashburn, K.L.; Tuomi, P.A.; Esler, Daniel; Mulcahy, D.M.; Rizzolo, D.J.

    2008-01-01

    Little is known about baseline concentrations of adrenal hormones and hormonal responses to stress in sea ducks, although significant population declines documented in several species suggest that sea ducks are exposed to increased levels of environmental stress. Such declines have been observed in geographically distinct harlequin duck populations. We performed an adrenocorticotropic hormone (ACTH) challenge to evaluate adrenal function and characterize corticosterone concentrations in captive harlequin ducks and investigated the effects of capture, surgery, and short term confinement on corticosterone concentrations in wild harlequin ducks. Harlequin ducks responded to the ACTH challenge with an average three-fold increase in serum corticosterone concentration approximately 90??min post injection, and a four- to five-fold increase in fecal glucocorticoid concentration 2 to 4??h post injection. Serum corticosterone concentrations in wild harlequin ducks increased within min of capture and elevated levels were found for several hours post capture, indicating that surgery and confinement maintain elevated corticosterone concentrations in this species. Mean corticosterone concentrations in wild harlequin ducks held in temporary captivity were similar to the maximum response levels during the ACTH challenge in captive birds. However, large variation among individuals was observed in responses of wild birds, and we found additional evidence suggesting that corticosterone responses varied between hatch year and after hatch year birds. ?? 2008.

  18. Ectopic ACTH Production Leading to Diagnosis of Underlying Medullary Thyroid Carcinoma

    PubMed Central

    Matheny, Leslee N.; Wilson, Jessica R.; Baum, Howard B. A.

    2016-01-01

    Medullary thyroid carcinoma (MTC) has been described as a source of ectopic ACTH secretion in patients with Cushing’s syndrome. This is an infrequent association, occurring in less than 1% of MTC cases. Among these, it is even more unusual for an initial diagnosis of hypercortisolism to lead to the discovery of underlying MTC. Here we present a case of a patient with weakness, diarrhea, and hypokalemia who was found first to have Cushing’s syndrome and later diagnosed with metastatic MTC. The patient was treated initially with oral agents to control his hypercortisolism, then with an etomidate infusion after experiencing intestinal perforation. He also received vandetanib therapy targeting his underlying malignancy, as this has been shown to reverse clinical signs of Cushing’s syndrome in patients with MTC and subsequent ectopic ACTH secretion. Bilateral adrenalectomy was ultimately required. Medullary thyroid carcinoma should be considered in patients presenting with Cushing’s syndrome due to ectopic ACTH secretion, and a multimodality treatment approach is often required. PMID:27141514

  19. Modified Clonidine Testing for Growth Hormone Stimulation Reveals α2-Adrenoreceptor Sub Sensitivity in Children with Idiopathic Growth Hormone Deficiency

    PubMed Central

    Willaschek, Christian; Meint, Sebastian; Rager, Klaus; Buchhorn, Reiner

    2015-01-01

    Introduction The association between short stature and increased risk of ischemic heart disease has been subject to studies for decades. The recent discussion of cardiovascular risk during growth hormone therapy has given new importance to this question. We have hypothesized that the autonomic system is a crucial element relating to this subject. Methods Heart rate variability calculated from 24-hour electrocardiogram data is providing insight into the regulatory state of the autonomous nervous system and is an approved surrogate parameter for estimating cardiovascular risk. We have calculated heart rate variability during clonidine testing for growth hormone stimulation of 56 children. As clonidine is a well-known effector of the autonomous system, stimulating vagal tone and decreasing sympathetic activity, we compared the autonomous reactions of children with constitutional growth delay (CGD), growth hormone deficiency (GHD) and former small for gestational age (SGA). Results During clonidine testing children with CGD showed the expected α2-adrenoreceptor mediated autonomous response of vagal stimulation for several hours. This vagal reaction was significantly reduced in the SGA group and nearly non- existent in the GHD group. Discussion Children with GHD show a reduced autonomous response to clonidine indicating α2-adrenoreceptor sub sensitivity. This can be found prior to the start of growth hormone treatment. Since reduction of HRV is an approved surrogate parameter, increased cardiovascular risk has to be assumed for patients with GHD. In the SGA group a similar but less severe reduction of the autonomous response to clonidine was found. These findings may enrich the interpretation of the data on growth hormone therapy, which are being collected by the SAGhE study group. PMID:26361394

  20. Role of ACTH in the Interactive/Paracrine Regulation of Adrenal Steroid Secretion in Physiological and Pathophysiological Conditions.

    PubMed

    Lefebvre, Hervé; Thomas, Michaël; Duparc, Céline; Bertherat, Jérôme; Louiset, Estelle

    2016-01-01

    In the normal human adrenal gland, steroid secretion is regulated by a complex network of autocrine/paracrine interactions involving bioactive signals released by endothelial cells, nerve terminals, chromaffin cells, immunocompetent cells, and adrenocortical cells themselves. ACTH can be locally produced by medullary chromaffin cells and is, therefore, a major mediator of the corticomedullary functional interplay. Plasma ACTH also triggers the release of angiogenic and vasoactive agents from adrenocortical cells and adrenal mast cells and, thus, indirectly regulates steroid production through modulation of the adrenal blood flow. Adrenocortical neoplasms associated with steroid hypersecretion exhibit molecular and cellular defects that tend to reinforce the influence of paracrine regulatory loops on corticosteroidogenesis. Especially, ACTH has been found to be abnormally synthesized in bilateral macronodular adrenal hyperplasia responsible for hypercortisolism. In these tissues, ACTH is detected in a subpopulation of adrenocortical cells that express gonadal markers. This observation suggests that ectopic production of ACTH may result from impaired embryogenesis leading to abnormal maturation of the adrenogonadal primordium. Globally, the current literature indicates that ACTH is a major player in the autocrine/paracrine processes occurring in the adrenal gland in both physiological and pathological conditions. PMID:27489549

  1. Physiological stress in captive Greater rheas (Rhea americana): highly sensitive plasma corticosterone response to an ACTH challenge.

    PubMed

    Lèche, Alvina; Busso, Juan M; Hansen, Cristian; Navarro, Joaquín L; Marín, Raúl H; Martella, Mónica B

    2009-06-01

    Up to the present no studies have been conducted either on baseline concentrations of adrenal hormones or on hormonal responses to stress in Greater rhea (Rhea americana) and most ratite species. The aims of this work were to assess the presence of corticosterone in plasma of Greater rhea, to validate a corticosterone (125)I-radioimmunoassay for determining corticosterone levels in plasma samples and to study the activation of the adrenal gland after an adrenocorticotrophic hormone (ACTH) challenge. Six captive Greater rhea juveniles of 10 months of age received an intravenous ACTH injection. Blood samples were taken at 0min (baseline pre-ACTH levels), and post-injection at 15, 30, 60min and at 24 and 48h. The high pressure liquid chromatography (HPLC) analysis of pooled plasma showed that corticosterone is the glucocorticoid found in the plasma of Greater rhea. Biochemical assays of standard validation (e.g., parallelism, exogenous corticosterone recovery) showed that measurements of corticosterone present in the plasma of the Greater rhea provided by commercial corticosterone (125)I-radioimmunoassay were accurate and precise. ACTH challenge induced a more than 40-fold increase in plasma corticosterone at 60min post-ACTH (from 4.0 to 166.5ng/ml, on average). The corticosterone response to ACTH in Greater rhea was higher than is usual in birds, an apparently typical characteristic of ratites.

  2. Role of ACTH in the Interactive/Paracrine Regulation of Adrenal Steroid Secretion in Physiological and Pathophysiological Conditions

    PubMed Central

    Lefebvre, Hervé; Thomas, Michaël; Duparc, Céline; Bertherat, Jérôme; Louiset, Estelle

    2016-01-01

    In the normal human adrenal gland, steroid secretion is regulated by a complex network of autocrine/paracrine interactions involving bioactive signals released by endothelial cells, nerve terminals, chromaffin cells, immunocompetent cells, and adrenocortical cells themselves. ACTH can be locally produced by medullary chromaffin cells and is, therefore, a major mediator of the corticomedullary functional interplay. Plasma ACTH also triggers the release of angiogenic and vasoactive agents from adrenocortical cells and adrenal mast cells and, thus, indirectly regulates steroid production through modulation of the adrenal blood flow. Adrenocortical neoplasms associated with steroid hypersecretion exhibit molecular and cellular defects that tend to reinforce the influence of paracrine regulatory loops on corticosteroidogenesis. Especially, ACTH has been found to be abnormally synthesized in bilateral macronodular adrenal hyperplasia responsible for hypercortisolism. In these tissues, ACTH is detected in a subpopulation of adrenocortical cells that express gonadal markers. This observation suggests that ectopic production of ACTH may result from impaired embryogenesis leading to abnormal maturation of the adrenogonadal primordium. Globally, the current literature indicates that ACTH is a major player in the autocrine/paracrine processes occurring in the adrenal gland in both physiological and pathological conditions. PMID:27489549

  3. Exocrine and endocrine functional reserve in the course of chronic pancreatitis as studied by maximal stimulation tests.

    PubMed

    Cavallini, G; Bovo, P; Zamboni, M; Bosello, O; Filippini, M; Riela, A; Brocco, G; Rossi, L; Pelle, C; Chiavenato, A

    1992-01-01

    Thirty patients suffering from chronic alcoholic pancreatitis (18 calcified) were entered into a study of exocrine and endocrine pancreatic function based on two maximal stimulation tests, namely the secretin-cerulein test and the glucagon test with serum assays of C peptide. The glucagon test was also performed in 19 control subjects. In addition, 10 chronic pancreatitis patients and nine controls were subjected to an oral glucose tolerance test (OGTT) with serum insulin determinations. C peptide basal values were decreased only in patients with severe pancreatic exocrine insufficiency (P less than 0.001), while delta C peptide values were also reduced in patients with moderate exocrine insufficiency (P less than 0.001). Lipase output correlated very well with delta C peptide values (P less than 0.001). While serum insulin levels during OGTT and C peptide basal values showed no significant differences between the chronic pancreatitis and control groups, delta C peptide values were significantly reduced in chronic pancreatitis patients (P less than 0.02). Both endocrine and exocrine function are impaired in chronic pancreatitis, as demonstrated by maximal tests, even in early stages of the disease.

  4. Geothermal fracture stimulation technology. Volume II. High-temperature proppant testing

    SciTech Connect

    Not Available

    1980-07-01

    Data were obtained from a newly built proppant tester, operated at actual geothermal temperatures. The short term test results show that most proppants are temperature sensitive, particularly at the higher closure stresses. Many materials have been tested using a standard short-term test, i.e., fracture-free sand, bauxite, and a resin-coated sand retained good permeability at the high fluid temperatures in brine over a range of closure stresses. The tests were designed to simulate normal closure stress ranges for geothermal wells which are estimated to be from 2000 to 6000 psi. Although the ultra high closure stresses in oil and gas wells need not be considered with present geothermal resources, there is a definite need for chemically inert proppants that will retain high permeability for long time periods in the high temperature formations.

  5. Luteinizing hormone and follicle stimulating hormone-releasing hormone test in patients with hypothalamic-pituitary-gonadal dysfunction.

    PubMed

    Mortimer, C H; Besser, G M; McNeilly, A S; Marshall, J C; Harsoulis, P; Tunbridge, W M; Gomez-Pan, A; Hall, R

    1973-10-13

    A standard intravenous 100 mug luteinizing hormone/follicle stimulating hormone-releasing hormone (LH/FSH-RH) test was used to assess the pituitary gonadotrophin responses in 155 patients with a variety of diseases of the hypothalamic-pituitary-gonadal axis. In all but nine patients there was an increase in circulating levels of either LH or FSH in response to the releasing hormone though 137 (88%) were clinically hypogonadal. It was not possible with this test to distinguish between hypothalamic and pituitary causes of hypogonadotrophic hypogonadism, since a variety of LH and FSH responses emerged within the disease groups. However, primary gonadal failure characteristically resulted in exaggerated gonadotrophin response. The potential therapeutic use of the gonadotrophin releasing decapeptide is suggested in certain patients with hypogonadotrophic hypogonadism.

  6. Effectiveness of Abstinence-Based Incentives: Interaction with Intake Stimulant Test Results

    ERIC Educational Resources Information Center

    Stitzer, Maxine L.; Petry, Nancy; Peirce, Jessica; Kirby, Kimberly; Killeen, Therese; Roll, John; Hamilton, John; Stabile, Patricia Q.; Sterling, Robert; Brown, Chanda; Kolodner, Ken; Li, Rui

    2007-01-01

    Intake urinalysis test result (drug positive vs. negative) has been previously identified as a strong predictor of drug abuse treatment outcome, but there is little information about how this prognostic factor may interact with the type of treatment delivered. The authors used data from a multisite study of abstinence incentives for stimulant…

  7. Stimulating Breadth and Depth of Vocabulary via Repeated Storybook Readings or Tests

    ERIC Educational Resources Information Center

    Damhuis, Carmen M. P.; Segers, Eliane; Verhoeven, Ludo

    2015-01-01

    We investigated effects of listening to single or multiple storybook readings versus testing with and without feedback on children's breadth (i.e., the number of words) and depth (i.e., the quality of word knowledge) of vocabulary learning. Kindergartners (n = 125) were divided into 3 intervention and 1 control conditions. Children in the control…

  8. The prolonged stimulatory effect of ACTH on 11 beta-hydroxylation, and its contribution to the steroidogenic potency of adrenocortical cells.

    PubMed

    Lambert, F; Lammerant, J; Kolanowski, J

    1984-04-01

    The mechanism of the prolonged stimulatory influence of corticotropin (ACTH) on the capacity of adrenocortical cells to produce cortisol in response to ACTH and more specifically the role of 11 beta-hydroxylation, was studied on guinea-pig adrenocortical cells dispersed from control and ACTH-treated animals. As a result of the previous in vivo exposure to ACTH, the net maximal production of glucocorticoids in response to ACTH (by 10(5) cells and 2 h incubation) increased from 660 +/- 33.9 ng (control group) to 1105 +/- 117.9 ng for cells from ACTH-treated animals (P less than 0.001), whereas the apparent affinity of the steroidogenic response remained unchanged. In addition there occurred an increased conversion of exogenous pregnenolone into cortisol by cells from ACTH-treated animals, indicating a prolonged stimulatory influence of ACTH on the post-pregnenolone pathway of cortisol biosynthesis. The activity of 11 beta-hydroxylation step was therefore examined by incubating the adrenocortical cells from control and ACTH-treated animals in the presence of increasing amounts of 11-deoxycortisol. The maximal capacity of 11-deoxycortisol conversion into cortisol was increased as a result of the in vivo exposure to ACTH, averaging 3423 +/- 211 ng cortisol formed from 5 micrograms 11-deoxycortisol by 10(5) cells from ACTH-treated animals vs 2074 +/- 185 ng for cells from control guinea-pigs (P less than 0.001). However, the conversion of lower amounts of 11-deoxycortisol into cortisol, reproducing quantitatively the maximal effect of ACTH on cortisol biosynthesis, was only barely increased in cells from ACTH-treated animals (P greater than 0.05). Therefore it was concluded that ACTH increases in a lasting way not only the overall steroidogenic capacity of adrenocortical cells but also the maximal efficiency of 11 beta-hydroxylation. Since the latter effect cannot account quantitatively for the magnitude of the lasting effect of ACTH on the maximal capacity of

  9. The development of a testosterone stimulation test in the Virginia opossum (Didelphis virginiana) and its use in evaluating deslorelin contraception.

    PubMed

    Johnston, S D; Camacho, F C; Carrillo, L; Guy, N; Govea, J; Martinez, O; Parãs, A; Lisle, A T; D'Occhio, M

    2008-01-01

    The aims of the present study were to examine the variability of testosterone secretion in the Virginia Opossum over a 24 h period and to develop a testosterone stimulation test that would provide an index of the prevailing testosterone biosynthetic capacity of the testes; the latter was used to clinically evaluate the efficacy of a gonadotrophin-releasing hormone agonist contraceptive. Sexually-mature captive opossums (n = 12) located in Africam Safari (Mexico) sampled every 12 h over 24 h consistently showed basal (<0.21 ng mL(-1)) blood testosterone concentrations. Intra-muscular injection of buserelin (2 microg mL(-1)) and human chorionic gonadotrophin (hCG; 1000 IU) resulted in an increase (P < 0.05) of plasma testosterone concentrations with maximal concentrations (3.9 ng mL(-1) and 5.8 ng mL(-1) respectively) occurring 120 min after injection. Plasma testosterone declined relatively rapidly to basal concentrations after 240 min with hCG but remained elevated after the same period of time with buserelin. Male opossums treated with (n = 6) and without (n = 6) a controlled-release deslorelin implant (Suprelorin; 4.7 mg deslorelin) were evaluated over a 10-week period for changes in testosterone secretion (hCG stimulation test) and sperm production (spermatorrhea). At the end of this period, the animals were hemi-castrated and their relative testicular quantitative histology compared. Testosterone concentration decreased over the course of the study in both treated and control animals (P < 0.0001) but there was no apparent effect of deslorelin on testosterone secretion, testicular histology (relative proportions of testicular cell types and seminiferous tubule diameter), or sperm production (presence of sperm in the cauda epididymis or urine).

  10. Effects of Attention Deficit Hyperactivity Disorder and Stimulant Medication on Concussion Symptom Reporting and Computerized Neurocognitive Test Performance.

    PubMed

    Littleton, Ashley C; Schmidt, Julianne D; Register-Mihalik, Johna K; Gioia, Gerard A; Waicus, Kelly M; Mihalik, Jason P; Guskiewicz, Kevin M

    2015-11-01

    Effects of attention deficit hyperactivity disorder (ADHD) and stimulant medications on concussion measures are unclear. The objectives of this study were to (i) examine consistency of performance in an unmedicated ADHD group and a control group on concussion measures, (ii) assess performance differences between the two groups, and (iii) assess the effect of stimulant medication on performance in the ADHD group. College-aged participants (22 ADHD and 22 matched controls) were administered a symptom checklist and a computerized neurocognitive test (CNS Vital Signs, CNSVS) 3 times (1 week apart): Sessions 1 and 2 were unmedicated for all participants; Session 3 was medicated for the ADHD group. The reliability of the measures (intraclass correlation coefficients, ICC2,1) was consistent for both groups. When unmedicated, the ADHD group performed worse than controls on psychomotor speed [F(1,40) = 15.19, p < 0.001], and worse than when medicated on reaction time [F(1,39) = 6.34, p = 0.02]. The ADHD group performed better and comparable with controls when medicated. Clinicians should take medication status into account when interpreting scores. PMID:26310392

  11. Test-retest assessment of cortical activation induced by repetitive transcranial magnetic stimulation with brain atlas-guided optical topography

    NASA Astrophysics Data System (ADS)

    Tian, Fenghua; Kozel, F. Andrew; Yennu, Amarnath; Croarkin, Paul E.; McClintock, Shawn M.; Mapes, Kimberly S.; Husain, Mustafa M.; Liu, Hanli

    2012-11-01

    Repetitive transcranial magnetic stimulation (rTMS) is a technology that stimulates neurons with rapidly changing magnetic pulses with demonstrated therapeutic applications for various neuropsychiatric disorders. Functional near-infrared spectroscopy (fNIRS) is a suitable tool to assess rTMS-evoked brain responses without interference from the magnetic or electric fields generated by the TMS coil. We have previously reported a channel-wise study of combined rTMS/fNIRS on the motor and prefrontal cortices, showing a robust decrease of oxygenated hemoglobin concentration (Δ[HbO2]) at the sites of 1-Hz rTMS and the contralateral brain regions. However, the reliability of this putative clinical tool is unknown. In this study, we develop a rapid optical topography approach to spatially characterize the rTMS-evoked hemodynamic responses on a standard brain atlas. A hemispherical approximation of the brain is employed to convert the three-dimensional topography on the complex brain surface to a two-dimensional topography in the spherical coordinate system. The test-retest reliability of the combined rTMS/fNIRS is assessed using repeated measurements performed two to three days apart. The results demonstrate that the Δ[HbO2] amplitudes have moderate-to-high reliability at the group level; and the spatial patterns of the topographic images have high reproducibility in size and a moderate degree of overlap at the individual level.

  12. Effects of Attention Deficit Hyperactivity Disorder and Stimulant Medication on Concussion Symptom Reporting and Computerized Neurocognitive Test Performance.

    PubMed

    Littleton, Ashley C; Schmidt, Julianne D; Register-Mihalik, Johna K; Gioia, Gerard A; Waicus, Kelly M; Mihalik, Jason P; Guskiewicz, Kevin M

    2015-11-01

    Effects of attention deficit hyperactivity disorder (ADHD) and stimulant medications on concussion measures are unclear. The objectives of this study were to (i) examine consistency of performance in an unmedicated ADHD group and a control group on concussion measures, (ii) assess performance differences between the two groups, and (iii) assess the effect of stimulant medication on performance in the ADHD group. College-aged participants (22 ADHD and 22 matched controls) were administered a symptom checklist and a computerized neurocognitive test (CNS Vital Signs, CNSVS) 3 times (1 week apart): Sessions 1 and 2 were unmedicated for all participants; Session 3 was medicated for the ADHD group. The reliability of the measures (intraclass correlation coefficients, ICC2,1) was consistent for both groups. When unmedicated, the ADHD group performed worse than controls on psychomotor speed [F(1,40) = 15.19, p < 0.001], and worse than when medicated on reaction time [F(1,39) = 6.34, p = 0.02]. The ADHD group performed better and comparable with controls when medicated. Clinicians should take medication status into account when interpreting scores.

  13. Insulin-induced hypoglycemia stimulates corticotropin-releasing factor and arginine vasopressin secretion into hypophysial portal blood of conscious, unrestrained rams.

    PubMed Central

    Caraty, A; Grino, M; Locatelli, A; Guillaume, V; Boudouresque, F; Conte-Devolx, B; Oliver, C

    1990-01-01

    Insulin-induced hypoglycemia (IIH) is a strong stimulator of pituitary ACTH secretion. The mechanisms by which IIH activates the corticotrophs are still controversial. Indeed, in rats the variations of corticotropin-releasing factor (CRF) and arginine vasopressin (AVP) secretion in hypophysial portal blood (HPB) during IIH have been diversely appreciated. This may be due to the stressful conditions required for portal blood collection in rats. We studied the effects of IIH on the secretion of CRF and AVP in HPB and on the release of ACTH and cortisol in peripheral plasma in conscious, unrestrained, castrated rams. After the injection of a low (0.2 IU/kg) or high dose (2 IU/kg) of insulin, ACTH and cortisol levels in peripheral plasma increased in a dose-related manner. After injection of the low dose of insulin, CRF and AVP secretion in HPB were equally stimulated. After injection of the high dose of insulin, CRF secretion was further stimulated, while AVP release was dramatically increased. These results suggest that when the hypoglycemia is moderate, CRF is the main factor triggering ACTH release, and that the increased AVP secretion potentiates the stimulatory effect of CRF. When hypoglycemia is deeper, AVP secretion becomes predominant and may by itself stimulate ACTH release. Images PMID:2161426

  14. Nur77 gene expression levels were involved in different ACTH-secretion autonomy between Cushing's disease and subclinical Cushing's disease.

    PubMed

    Tabuchi, Yukiko; Kitamura, Tetsuhiro; Fukuhara, Atsunori; Mukai, Kosuke; Onodera, Toshiharu; Miyata, Yugo; Hamasaki, Toshimitsu; Oshino, Satoru; Saitoh, Youichi; Morii, Eiichi; Otsuki, Michio; Shimomura, Iichiro

    2016-06-30

    Cushing's disease (CD) and subclinical Cushing's disease (subCD) are both diseases caused by adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas. However, ACTH autonomy in subCD is weaker than in CD and there are no Cushingoid features in subCD. The differences of molecular mechanisms in ACTH autonomy between CD and subCD have not yet been reported. Therefore, we aimed to investigate the differences in molecular mechanisms of ACTH-secretion autonomy between CD and subCD. The study included 23 patients [7 CD, 6 subCD, and 10 non-functioning pituitary tumors (NFTs)] who underwent transsphenoidal surgery at the Osaka University Hospital between December 2009 and October 2013. Using quantitative real-time PCR, various ACTH-related gene expressions in tumor tissues from CD, subCD, and NFT were measured such as pro-opiomelanocortin (POMC), POMC transcription factor (Tpit, Pitx1, NeuroD1, and Nur77), POMC peptide processing enzymes (prohormone convertase: PC1/3 and PC2), and ACTH secretion-related factors (corticotropin-releasing hormone receptor 1: CRHR1 and glucocorticoid receptor α: GRα). Only Nur77 mRNA levels were significantly higher in CD than in subCD. Furthermore, we stained 6 CD and 6 subCD with anti-Nur77 antibody. All tumor samples from CD had Nur77 protein positive cells. On the other hand, Nur77 protein was expressed in only one tumor sample from subCD. This sample showed high expression of Nur77 mRNA. Nur77 is an important to regulate POMC transcription and negative-feedback by glucocorticoids. Nur77 gene expression levels might involve different autonomy of ACTH production between CD and subCD. PMID:27025408

  15. Nur77 gene expression levels were involved in different ACTH-secretion autonomy between Cushing's disease and subclinical Cushing's disease.

    PubMed

    Tabuchi, Yukiko; Kitamura, Tetsuhiro; Fukuhara, Atsunori; Mukai, Kosuke; Onodera, Toshiharu; Miyata, Yugo; Hamasaki, Toshimitsu; Oshino, Satoru; Saitoh, Youichi; Morii, Eiichi; Otsuki, Michio; Shimomura, Iichiro

    2016-06-30

    Cushing's disease (CD) and subclinical Cushing's disease (subCD) are both diseases caused by adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas. However, ACTH autonomy in subCD is weaker than in CD and there are no Cushingoid features in subCD. The differences of molecular mechanisms in ACTH autonomy between CD and subCD have not yet been reported. Therefore, we aimed to investigate the differences in molecular mechanisms of ACTH-secretion autonomy between CD and subCD. The study included 23 patients [7 CD, 6 subCD, and 10 non-functioning pituitary tumors (NFTs)] who underwent transsphenoidal surgery at the Osaka University Hospital between December 2009 and October 2013. Using quantitative real-time PCR, various ACTH-related gene expressions in tumor tissues from CD, subCD, and NFT were measured such as pro-opiomelanocortin (POMC), POMC transcription factor (Tpit, Pitx1, NeuroD1, and Nur77), POMC peptide processing enzymes (prohormone convertase: PC1/3 and PC2), and ACTH secretion-related factors (corticotropin-releasing hormone receptor 1: CRHR1 and glucocorticoid receptor α: GRα). Only Nur77 mRNA levels were significantly higher in CD than in subCD. Furthermore, we stained 6 CD and 6 subCD with anti-Nur77 antibody. All tumor samples from CD had Nur77 protein positive cells. On the other hand, Nur77 protein was expressed in only one tumor sample from subCD. This sample showed high expression of Nur77 mRNA. Nur77 is an important to regulate POMC transcription and negative-feedback by glucocorticoids. Nur77 gene expression levels might involve different autonomy of ACTH production between CD and subCD.

  16. Reference values of serum calcitonin with calcium stimulation tests by electrochemiluminescence immunoassay before/after total thyroidectomy in Japanese patients with thyroid diseases other than medullary thyroid carcinoma.

    PubMed

    Kihara, Minoru; Miyauchi, Akira; Kudo, Takumi; Hirokawa, Mitsuyoshi; Miya, Akihiro

    2016-07-30

    Calcitonin is a very sensitive tumor marker of medullary thyroid carcinoma (MTC). MTC patients usually have very high values of serum calcitonin that can be used to diagnose the disease. To improve the diagnostic sensitivity in family members with small MTCs and to evaluate the postoperative biochemical cure status, a calcium stimulation test is widely used. Serum calcitonin has been measured using several methods, but in Japan, only an electrochemiluminescence immunoassay (ECLIA) is currently performed to determine serum calcitonin. Reference values for the calcium stimulation test using an ECLIA have not been reported. Here we conducted a calcium stimulation tests in 26 patients without MTC before and after total thyroidectomy. Preoperatively, the basal calcitonin values of all patients were within normal limits and increased to a mean of 14.4 pg/mL after calcium stimulation. We transformed the peak values before total thyroidectomy to a logarithmic distribution and calculated the normalized mean ± 1.96× standard deviation; the reference upper limit was thus expressed. In the female patients with non-MTC, the reference upper limit was 67.6 pg/mL. In all patients, the calcium stimulation test results after total thyroidectomy showed undetectable basal and stimulated calcitonin values (<0.5 pg/mL). This is the first study to determine reference values to be used for the calcium stimulation test along with an ECLIA in non-MTC patients. We propose that female patients are regarded as biochemically cured or normal when the stimulated calcitonin values by ECLIA are <67.6 pg/mL before surgery and <0.5 pg/mL after total thyroidectomy. PMID:27097651

  17. Antidepressant actions of lateral habenula deep brain stimulation differentially correlate with CaMKII/GSK3/AMPK signaling locally and in the infralimbic cortex.

    PubMed

    Kim, Yesul; Morath, Brooke; Hu, Chunling; Byrne, Linda K; Sutor, Shari L; Frye, Mark A; Tye, Susannah J

    2016-06-01

    High frequency deep brain stimulation (DBS) of the lateral habenula (LHb) reduces symptoms of depression in severely treatment-resistant individuals. Despite the observed therapeutic effects, the molecular underpinnings of DBS are poorly understood. This study investigated the efficacy of high frequency LHb DBS (130Hz; 200μA; 90μs) in an animal model of tricyclic antidepressant resistance. Further, we reported DBS mediated changes in Ca(2+)/calmodulin-dependent protein kinase (CaMKIIα/β), glycogen synthase kinase 3 (GSK3α/β) and AMP-activated protein kinase (AMPK) both locally and in the infralimbic cortex (IL). Protein expressions were then correlated to immobility time during the forced swim test (FST). Antidepressant actions were quantified via FST. Treatment groups comprised of animals treated with adrenocorticotropic hormone alone (ACTH; 100μg/day, 14days, n=7), ACTH with active DBS (n=7), sham DBS (n=8), surgery only (n=8) or control (n=8). Active DBS significantly reduced immobility in ACTH-treated animals (p<0.05). For this group, western blot results demonstrated phosphorylation status of LHb CaMKIIα/β and GSK3α/β significantly correlated to immobility time in the FST. Concurrently, we observed phosphorylation status of CaMKIIα/β, GSK3α/β, and AMPK in the IL to be negatively correlated with antidepressant actions of DBS. These findings suggest that activity dependent phosphorylation of CaMKIIα/β, and GSK3α/β in the LHb together with the downregulation of CaMKIIα/β, GSK3α/β, and AMPK in the IL, contribute to the antidepressant actions of DBS. PMID:26956153

  18. Negative correlation between peripheral plasma somatostatin levels and GH responses to GH-RH stimulation tests in children.

    PubMed

    Liapi, C; Evain Brion, D; Argente, J; Vaudry, H; Donnadieu, M

    1986-09-01

    On forty-six fasting and resting children, aged 5-17 years, with short stature (below -2 SD) a growth hormone releasing hormone (GH-RH) stimulation test (2 micrograms/kg iv bolus, Sanofi) was performed. Twenty-two children were prepubertal, of which, 13 had a constitutional short stature (CSS), nine an idiopathic growth hormone deficiency (IGHD). Twenty-four subjects were pubertal, at the stage II or III of Tanner. Among them, six had a constitutional short stature (CSS) and 18 an idiopathic delayed puberty (IDP). Blood samples were taken for determination of plasma somatostatin-like immunoreactivity (SLI) in chilled test tubes containing EDTA + aprotinin. Plasma SLI levels were measured after extraction and concentration on C18 Sep Pack columns by radioimmunoassay using an antibody against 1-14 somatostatin. The sensitivity of this assay is around 3 pg/ml. After GH-RH stimulation the peak of GH (mean +/- SEM) was in prepubertal subjects: 25.3 +/- 9.1 micrograms/l in CSS, and 18.6 +/- 10.3 micrograms/l in IGHD. In pubertal subjects GH peaks were 17.6 +/- 8.4 micrograms/l in CSS and 15.6 +/- 3.8 micrograms/l in children with IDP. No significant differences was found between basal plasma SLI levels in the four groups of subjects, being respectively (mean +/- SEM) 11.9 +/- 1.8 pg/ml in prepubertal subjects with CSS, 9.6 +/- 2.6 pg/ml in IGHD, 7.6 +/- 1.7 pg/ml in pubertal children with CSS and 6.6 +/- 1.5 pg/ml in children with IDP.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Diagnostic accuracy of basal TSH determinations based on the intravenous TRH stimulation test: An evaluation of 2570 tests and comparison with the literature

    PubMed Central

    Moncayo, Helga; Dapunt, Otto; Moncayo, Roy

    2007-01-01

    Background Basal TSH levels reflect the metabolic status of thyroid function, however the definition and interpretation of the basal levels of TSH is a matter of controversial debate. The aim of this study was to evaluate basal TSH levels in relation to the physiological response to i.v. TRH stimulation. Methods A series of 2570 women attending a specialized endocrine unit were evaluated. A standardized i.v. TRH stimulation test was carried out by applying 200 μg of TRH. TSH levels were measured both in the basal and the 30 minute blood sample. The normal response to TRH stimulation had been previously determined to be an absolute value lying between 2.5 and 20 mIU/l. Both TSH values were analyzed by cross tabulation. In addition the results were compared to reference values taken from the literature. Results Basal TSH values were within the normal range (0.3 to 3.5 mIU/l) in 91,5% of cases, diminished in 3,8% and elevated in 4.7%. Based on the response to TRH, 82.4% were considered euthyroid, 3.3% were latent hyperthyroid, and 14.3% were latent hypothyroid. Combining the data on basal and stimulated TSH levels, latent hypothyroidism was found in the following proportions for different TSH levels: 5.4% for TSH < 2.0 mIU/l, 30.2% for TSH between 2.0 and 3.0 mIU/l, 65,5% for TSH between 3.0 and 3.50 mIU/l, 87.5% for TSH between 3.5 and 4.0 mIU/l, and 88.2% for TSH between 4 and 5 mIU/l. The use of an upper normal range for TSH of 2.5 mIU/l, as recommended in the literature, misclassified 7.7% of euthyroid cases. Conclusion Our analysis strategy allows us to delineate the predictive value of basal TSH levels in relation to latent hypothyroidism. A grey area can be identified for values between 3.0 and 3.5 mIU/l. PMID:17678551

  20. [Mitral valve prolapse. Atrial stimulation, ajmaline test and "pharmacological denervation" in the evaluation of ventricular repolarization].

    PubMed

    Gil, R; Kaźmierczak, J; Kornacewicz-Jach, Z; Zinka, E

    1992-08-01

    In patients with mitral valve prolapse syndrome (MVP) various electrophysiological abnormalities occur. There are convergent opinions concerning QT distance variability and the influence of autonomic nervous system on ventricular repolarization in this syndrome. In 38 MVP patients (group I) and 24 subjects without this abnormality (group II) ecg was recorded during transvenous right atrial pacing at baseline, after ajmaline administration and after pharmacological autonomic blockade (atropine + propranolol). The following ventricular repolarization parameters were analysed: QTe (distance to the end of T wave), JTe (distance between J point and the end of T wave--so called "pure repolarization"), QTdys (repolarization dispersion) and the corrected QTc.QTe during 90/min right atrial pacing was significantly shorter than QTc in both groups. QTc was abnormally prolonged (above 440 msec) in MVP group. Ajmaline administration prolonged QTe in group II only, whereas autonomic blockade resulted in marked shortening of QTe in MVP group. QTdys was significantly prolonged only after ajmaline administration in group II. Based on above results, the following conclusions are made: 1) Right atrial pacing technique may be used for calculating standardized QT distance, an alternative to corrected QT. 2) Ajmaline test is useless in ventricular repolarization estimations in MVP patients. 3) In MVP patients the influence of adrenergic system on ventricular repolarization at rest appears to be greater than in non-MVP subjects. PMID:1434330

  1. Effects of RXR Agonists on Cell Proliferation/Apoptosis and ACTH Secretion/Pomc Expression

    PubMed Central

    Saito-Hakoda, Akiko; Uruno, Akira; Yokoyama, Atsushi; Shimizu, Kyoko; Parvin, Rehana; Kudo, Masataka; Saito-Ito, Takako; Sato, Ikuko; Kogure, Naotaka; Suzuki, Dai; Shimada, Hiroki; Yoshikawa, Takeo; Fujiwara, Ikuma; Kagechika, Hiroyuki; Iwasaki, Yasumasa; Kure, Shigeo; Ito, Sadayoshi; Sugawara, Akira

    2015-01-01

    Various retinoid X receptor (RXR) agonists have recently been developed, and some of them have shown anti-tumor effects both in vivo and in vitro. However, there has been no report showing the effects of RXR agonists on Cushing’s disease, which is caused by excessive ACTH secretion in a corticotroph tumor of the pituitary gland. Therefore, we examined the effects of synthetic RXR pan-agonists HX630 and PA024 on the proliferation, apoptosis, ACTH secretion, and pro-opiomelanocortin (Pomc) gene expression of murine pituitary corticotroph tumor AtT20 cells. We demonstrated that both RXR agonists induced apoptosis dose-dependently in AtT20 cells, and inhibited their proliferation at their higher doses. Microarray analysis identified a significant gene network associated with caspase 3 induced by high dose HX630. On the other hand, HX630, but not PA024, inhibited Pomc transcription, Pomc mRNA expression, and ACTH secretion dose-dependently. Furthermore, we provide new evidence that HX630 negatively regulates the Pomc promoter activity at the transcriptional level due to the suppression of the transcription factor Nur77 and Nurr1 mRNA expression and the reduction of Nur77/Nurr1 heterodimer recruiting to the Pomc promoter region. We also demonstrated that the HX630-mediated suppression of the Pomc gene expression was exerted via RXRα. Furthermore, HX630 inhibited tumor growth and decreased Pomc mRNA expression in corticotroph tumor cells in female nude mice in vivo. Thus, these results indicate that RXR agonists, especially HX630, could be a new therapeutic candidate for Cushing’s disease. PMID:26714014

  2. Infundibular neurons of the human hypothalamus simultaneously reactive with antisera against endorphins, ACTH, MSH and beta-LPH.

    PubMed

    Bugnon, C; Bloch, B; Lenys, D; Fellmann, D

    1979-06-27

    In man, discrete neurons of the infundibular (arcuate) nucleus contain compounds that can be stained with anti-endorphin (alpha and beta), anti-ACTH, anti-MSH (alpha and beta) and anti-beta-LPH immune sera (I.S.). In the fetus, certain neurons stain with anti-beta-endorphin or anti((17--39)ACTH starting from the 11th week of fetal life. At the ultrastructural level, these neurons contain elementary granules that are immunoreactive with anti-beta-endorphin. In the adult, neurons immunoreactive with anti-beta-endorphin are found in the infundibular nucleus. Their axonal fibers terminate around blood vessels in the neurovascular zone and in the pituitary stalk, or establish contacts with non-immunoreactive perikarya of the infundibular nucleus. These neurons can be stained with anti(17--39)ACTH and anti-beta-endorphin I.S. The most reactive are also stained moderately with anti-alpha-MSH, anti-beta-MSH, anti-beta-LPH, anti-alpha-endorphin, or anti(1--24)ACTH I.S. These results indicate that, in man, compound(s) identical with or immunologically related to endorphins, beta-LPH, ACTH and MSH are secreted by certain hypothalamic neurons. These agents probably originate from a common precursor molecula similar to the so-called pro-opiocortin.

  3. Ectopic Cushing’s syndrome due to retroperitoneal ACTH-producing paragangliomas

    PubMed Central

    Chen, Fan; Wang, Xiangyu; Wang, Yang; Meng, Hui; Hou, Xinguo; Zhu, Yaofeng; Gao, Wei; Jiang, Xuewen; Chen, Shouzhen; Zhang, Zhaocun; Zou, Zhichuan; He, Tianyi; Yang, Yue; Zhu, Kejia; Wang, Yong; Liu, Yaxiao; Cui, Jianfeng; Shi, Benkang; Yin, Gang

    2016-01-01

    Extra-adrenal pheochromocytomas, or paragangliomas, are rare tumours that derive from extra-adrenal chromaffin cells. Cushing’s syndrome (CS) caused by paragangliomas is extremely rare. We report a 53-year-old man with hypertension, diabetes, and symptoms of hypokalemia. Computer tomography (CT) revealed two retroperitoneal masses and bilateral adrenal hyperplasia. Together with the laboratory examinations, ectopic CS caused by multiple paragangliomas was highly suspected. The patient underwent resections of retroperitoneal tumours, left kidney, and left adrenal; postoperative histopathology confirmed two paragangliomas that were both positively stained for adrenocorticotropic hormone (ACTH). He got clinical and biochemical recoveries without any recurrent evidence at the nine-month followup.

  4. Ectopic Cushing’s syndrome due to retroperitoneal ACTH-producing paragangliomas

    PubMed Central

    Chen, Fan; Wang, Xiangyu; Wang, Yang; Meng, Hui; Hou, Xinguo; Zhu, Yaofeng; Gao, Wei; Jiang, Xuewen; Chen, Shouzhen; Zhang, Zhaocun; Zou, Zhichuan; He, Tianyi; Yang, Yue; Zhu, Kejia; Wang, Yong; Liu, Yaxiao; Cui, Jianfeng; Shi, Benkang; Yin, Gang

    2016-01-01

    Extra-adrenal pheochromocytomas, or paragangliomas, are rare tumours that derive from extra-adrenal chromaffin cells. Cushing’s syndrome (CS) caused by paragangliomas is extremely rare. We report a 53-year-old man with hypertension, diabetes, and symptoms of hypokalemia. Computer tomography (CT) revealed two retroperitoneal masses and bilateral adrenal hyperplasia. Together with the laboratory examinations, ectopic CS caused by multiple paragangliomas was highly suspected. The patient underwent resections of retroperitoneal tumours, left kidney, and left adrenal; postoperative histopathology confirmed two paragangliomas that were both positively stained for adrenocorticotropic hormone (ACTH). He got clinical and biochemical recoveries without any recurrent evidence at the nine-month followup. PMID:27695589

  5. ACTH, corticosterone, and beta-endorphin in rat blood plasma after prolonged immobilization stress

    SciTech Connect

    Kiyatkin, E.A.; Amiragova, M.G.; Kushlinskii, N.E.; Polyntsev, Yu. V.

    1986-01-01

    To assess functional relations between changes in ACTH, beta-endorphin (BE), and corticosterone (CS) levels, plasma concentrations of these hormones were studied in rats during the development of prolonged immobilization stress. Plasma hormone concentrations were determined by radioimmunoassay. The results were analyzed by standard statistical methods on a microcomputer. A particular feature about the kit used to determine BE was the presence of 50% cross-reactivity of the antiserum against beta-lipotrophin. To determine CS a highly specific antiserum produced by a laboratory was used.

  6. Elevation of plasma glucose, alanine, and urea levels by mammalian ACTH in the American bullfrog (Rana catesbeiana).

    PubMed

    Rosenthal, E J; deRoos, R

    1985-08-01

    The effects of a single infusion of mammalian ACTH on plasma glucose, alanine, urea, and lactate were determined in the American bullfrog (Rana catesbeiana). The ACTH (10 U/250 g body wt) was administered, and serial blood samples were collected via a nonocclusive cannula chronically placed in the right truncus arteriosus. Plasma metabolite levels were estimated by standard enzymatic techniques. The plasma metabolites declined following the surgery to levels that were relatively stable by postoperative Day 2. The levels did not vary significantly for the remainder of the 3- or 4-day pretreatment period and in the control bullfrogs during the 48-hr experiments. Plasma glucose levels were essentially unchanged from the time-zero levels at 6 hr following ACTH infusion. Plasma glucose levels subsequently increased to levels that were approximately 24% greater than the control levels by 24 hr and then declined to near control levels by 48 hr. Plasma alanine increased to levels that were approximately 60% greater than the control levels by 12 hr after ACTH treatment and returned to essentially the time-zero levels by 24 hr. Plasma urea rose to levels that were approximately 110% greater than the control levels by 45 min after ACTH infusion, but urea returned to essentially the time-zero levels by 1.5 through 3 hr. Plasma urea increased again to levels that were approximately 90% greater than the control levels by 6 hr and returned to essentially the initial levels by 24 hr. Plasma lactate levels were not significantly influenced by ACTH treatment. The results suggest that a function of the bullfrog hypothalamic-pituitary-adrenocortical axis is to regulate gluconeogenesis from alanine, and probably other glucogenic amino acids.

  7. Cushing's storm secondary to a rare case of ectopic ACTH secreting metastatic breast cancer

    PubMed Central

    Bucciarelli, Maura; Lee, Ya-Yu

    2015-01-01

    Summary Ectopic ACTH secretion from breast cancer is extremely rare. We report a case of a 30-year-old woman with a history of breast cancer, who presented with psychosis and paranoid behaviour. CT of the head showed white matter disease consistent with posterior reversible encephalopathy syndrome (PRES). Despite using mifepristone with multiple antihypertensives including lisinopril, spironolactone and metoprolol, she was hypertensive. Transaminitis did not allow mifepristone dose escalation and ketoconazole utilization. Etomidate infusion at a non-sedating dose in the intensive care unit controlled her hypertension and cortisol levels. She was transitioned to metyrapone and spironolactone. She was discharged from the hospital on metyrapone with spironolactone and underwent chemotherapy. She died 9 months later after she rapidly redeveloped Cushing's syndrome and had progressive metastatic breast cancer involving multiple bones, liver and lungs causing respiratory failure. Learning points Cushing's syndrome from ectopic ACTH secreting breast cancer is extremely rare.Cushing's syndrome causing psychosis could be multifactorial including hypercortisolism and PRES.Etomidate at non-sedating doses in intensive care setting can be effective to reduce cortisol production followed by transition to oral metyrapone. PMID:26525183

  8. Secretin stimulation test (image)

    MedlinePlus

    ... pancreas to secrete a fluid with a high concentration of bicarbonate. This fluid neutralizes the acidity from the stomach that is necessary for a number of enzymes to function in the breakdown and absorption of ...

  9. Testing the Role of Dorsal Premotor Cortex in Auditory-Motor Association Learning Using Transcranical Magnetic Stimulation (TMS)

    PubMed Central

    Lega, Carlotta; Stephan, Marianne A.; Zatorre, Robert J.; Penhune, Virginia

    2016-01-01

    Interactions between the auditory and the motor systems are critical in music as well as in other domains, such as speech. The premotor cortex, specifically the dorsal premotor cortex (dPMC), seems to play a key role in auditory-motor integration, and in mapping the association between a sound and the movement used to produce it. In the present studies we tested the causal role of the dPMC in learning and applying auditory-motor associations using 1 Hz repetitive Transcranical Magnetic Stimulation (rTMS). In this paradigm, non-musicians learn a set of auditory-motor associations through melody training in two contexts: first when the sound to key-press mapping was in a conventional sequential order (low to high tones mapped onto keys from left to right), and then when it was in a novel scrambled order. Participant’s ability to match the four pitches to four computer keys was tested before and after the training. In both experiments, the group that received 1 Hz rTMS over the dPMC showed no significant improvement on the pitch-matching task following training, whereas the control group (who received rTMS to visual cortex) did. Moreover, in Experiment 2 where the pitch-key mapping was novel, rTMS over the dPMC also interfered with learning. These findings suggest that rTMS over dPMC disturbs the formation of auditory-motor associations, especially when the association is novel and must be learned rather explicitly. The present results contribute to a better understanding of the role of dPMC in auditory-motor integration, suggesting a critical role of dPMC in learning the link between an action and its associated sound. PMID:27684369

  10. Chromium Isotopic Monitoring of HRC-Stimulated Bio-containment at the 100H Test Site, Hanford, Washington

    NASA Astrophysics Data System (ADS)

    Christensen, J. N.; Brown, S. T.; Brodie, E. L.; Chakraborty, R.; Conrad, M. E.; Long, P. E.; Faybishenko, B.; Hazen, T. C.

    2007-12-01

    Hexavalent Cr (Cr(VI)) groundwater contamination is a common problem in the U.S. associated with industrial activity (e.g. electroplating, tanning, paints, anti-corrosion). In the particular case of the Hanford Site, Washington, chromate was used primarily to inhibit corrosion in nuclear reactor cooling systems. During the active operation of the Hanford Site, disposal of waste water bearing chromate, and accidental releases to the vadose zone resulted in significant groundwater contamination with local concentrations near the Columbia river reaching over 1000 ppb Cr(VI). In an effort to test an effective bio-containment strategy for groundwater Cr(VI), a site was selected between the 100D and 100H reactor areas with modest concentrations (~100 ppb Cr(VI) over the past two decades). A slow-release 13C labeled polylactate amendment (HRCTM, Regenesis, Ltd.) was injected into groundwater within a sandy formation to stimulate bacterial activity in order to produce conditions that promote the reduction of dissolved Cr(VI) to insoluble Cr(III) complexes [1]. Since the injection of HRCTM in August 2004, groundwater Cr(VI) concentration has been locally below 1 ppb, and reducing conditions have been maintained to at least the present time. The isotopic composition of Cr can be fractionated during reduction from Cr(VI) to Cr(III) and so has the potential to be used as a monitor of hexavalent Cr reduction [2, 3]. This would provide a direct signature of Cr(VI) reduction, discernable from simple attenuation by dilution. In order to explore the use of Cr isotopic measurements for evaluating processes of Cr(VI) reduction, we have analyzed a series of samples in space and time for Cr isotopic composition (δ53Cr, permil deviation of sample 53Cr/52Cr from that of SRM970). Groundwater samples came from the HRC injection well, from multiple depths of three down-gradient wells, and from an up-gradient well. Samples from down-gradient wells have Cr that is isotopically fractionated

  11. Subclinical hypothyroidism diagnosed by thyrotropin-releasing hormone stimulation test in infertile women with basal thyroid-stimulating hormone levels of 2.5 to 5.0 mIU/L

    PubMed Central

    Lee, You-Jeong; Kwack, Jae-Young; Ahn, Jun-Woo; Kim, Sung-Hoon; Chae, Hee-Dong; Kang, Byung-Moon

    2014-01-01

    Objective To investigate the prevalence of subclinical hypothyroidism (SH) diagnosed by thyrotropin-releasing hormone (TRH) stimulating test in infertile women with basal thyroid-stimulating hormone (TSH) levels of 2.5 to 5.0 mIU/L. Methods This study was performed in 39 infertile women with ovulatory disorders (group 1) and 27 infertile women with male infertility only (group 2, controls) who had basal serum TSH levels of 2.5 to 5.0 mIU/L and a TRH stimulating test. Serum TSH levels were measured before TRH injection (TSH0) and also measured at 20 minutes (TSH1) and 40 minutes (TSH2) following intravenous injection of 400 µg TRH. Exaggerated TSH response above 30 mIU/L following TRH injection was diagnosed as SH. Group 1 was composed of poor responders (subgroup A), patients with polycystic ovary syndrome (subgroup B) and patients with WHO group II anovulation except poor responder or polycystic ovary syndrome (subgroup C). Results The prevalence of SH was significantly higher in group 1 of 46.2% (18/39) compared with 7.4% (2/27) in group 2 (P=0.001). TSH0, TSH1, and TSH2 levels were significantly higher in group 1 than the corresponding values in group 2 (P<0.001, P<0.001, P<0.001). In group 1, TSH1 and TSH2 levels were significantly lower in subgroup C compared with those in subgroup A and B (P=0.008, P=0.006, respectively). Conclusion TRH stimulation test had better be performed in infertile women with ovulatory disorders who have TSH levels between 2.5 and 5.0 mIU/L for early detection and appropriate treatment of SH. PMID:25469340

  12. Sensitivity of Four Subtests of the Test of Everyday Attention For Children (TEA-Ch) to Stimulant Medication in Children with ADHD

    ERIC Educational Resources Information Center

    Sutcliffe, Paul A.; Bishop, Dorothy V.M.; Houghton, Stephen

    2006-01-01

    Children with attention deficit hyperactivity disorder (ADHD) were examined on four subtests of the Test of Everyday Attention for Children (TEA-Ch) when on and off stimulant medication. Performance was assessed relative to 18 individually age-matched controls. Children with ADHD performed significantly worse on TEA-Ch measures when off compared…

  13. The Use of the Bilingual Aphasia Test for Assessment and Transcranial Direct Current Stimulation to Modulate Language Acquisition in Minimally Verbal Children with Autism

    ERIC Educational Resources Information Center

    Schneider, Harry D.; Hopp, Jenna P.

    2011-01-01

    Minimally verbal children with autism commonly demonstrate language dysfunction, including immature syntax acquisition. We hypothesised that transcranial direct current stimulation (tDCS) should facilitate language acquisition in a cohort (n = 10) of children with immature syntax. We modified the English version of the Bilingual Aphasia Test (BAT)…

  14. [Effect of dalargin on the content of endorphins, leucine-enkephalin ACTH and corticosterone of the blood of stressed rats].

    PubMed

    Bobkov, A I; Polonskiĭ, V M; Vinogradov, V A; Demina, D G; Smagin, V G

    1985-12-01

    Stress caused by acute cysteamine duodenal ulcer was induced in Wistar male rats. All the endogenous opioides under study were involved in the stress-reaction mechanism. Protective dalargin (synthetic enkephalin analogue) administration revealed a tendency towards normalization of endorphin, L-enkephalin and ACTH blood levels.

  15. The effects of stress on plasma ACTH and corticosterone in young and aging pregnant rats and their fetuses

    SciTech Connect

    Erisman, S. ); Carnes, M. Univ. of Wisconsin, Madison ); Takahashi, L.K.; Lent, S.J. )

    1990-01-01

    Compared to younger rats, old rats exhibit prolonged elevations of plasma ACTH and corticosterone (CORT) in response to stress. In addition, CORT crosses the placenta. To investigate whether fetuses of older rats may be exposed to higher concentrations of CORT during development than fetuses of young rats, we compared the effects of stress on hypothalamic-pituitary-adrenal (HPA) axis function in young and aging pregnant rats and their 19-day-old fetuses. The plasma of the mothers and fetuses was assayed for ACTH and CORT by radioimmunoassay. Both young and aging pregnant rats showed a significant increase in plasma ACTH and CORT immediately after exposure to stress. However, aging rats had more prolonged elevation of ACTH and CORT than young rats. This suggests that, like old male rats, aging pregnant rats have an alteration in feedback inhibition of the HPA axis. Prolonged elevation of CORT was also seen in fetuses of aging mothers. These results have important implications concerning the effects of stress during pregnancy at different maternal ages, and for the potential deleterious consequences of prolonged prenatal elevation in stress hormones on the offspring of aging females.

  16. Treadmill exercise training and estradiol increase plasma ACTH and prolactin after novel footshock.

    PubMed

    White-Welkley, J E; Warren, G L; Bunnell, B N; Mougey, E H; Meyerhoff, J L; Dishman, R K

    1996-03-01

    We examined whether rats that were treadmill exercise trained (Tr) or chronically immobilized (CI) had similar responses by the hypothalamic-pituitary-adrenal (HPA) cortical axis to acute stress and whether the HPA responses interacted with the hypothalamic-pituitary-gonadal (HPG) axis. After 6 wk (1 h/day, 6 days/wk) of Tr or CI, plasma concentrations of adrenocorticotropic hormone ([ACTH]), [prolactin], and [corticosterone] were measured after familiar (treadmill running or immobilization) or novel (footshock) stress. Ovariectomized Sprague-Dawley females (n = 72) were implanted with capsules containing estradiol benzoate (E2) and randomly assigned in a 2-group (E2 vs. no E2) x 3 treatment (Tr vs. CI vs. sedentary) x 4 acute stressor [footshock vs. treadmill running (Run) vs. immobilization (Im) vs. no stress] x 3 recovery time (1 vs. 15 vs. 30 min) mixed-model analysis of variance. E2 capsules were removed from one-half of the animals 48 h before the first stressor session. After 10 min of acute stress, blood was drawn from a jugular catheter at 1, 15, and 30 min of recovery. [ACTH] and [prolactin] after footshock were higher in Tr rats with E2 compared with CI and sedentary rats without E2; recovery levels for sedentary animals were higher after Run compared with Im. The elevation in [corticosterone] from minute 1 to 15 of recovery was higher after the familiar Run and Im conditions. Our findings are consistent with an increased responsiveness of the HPA axis to novel footshock after treadmill exercise training that is additionally modulated by the HPG axis.

  17. A case of insulin and ACTH co-secretion by a neuroendocrine tumour

    PubMed Central

    Solomou, S; Khan, R; Propper, D; Berney, D; Druce, M

    2014-01-01

    Summary A 33-year-old male was diagnosed with a metastatic neuroendocrine carcinoma of uncertain primary. He defaulted from follow-up without therapy and some months later developed episodic severe hypoglycaemia, which was found to be associated with inappropriately elevated insulin and C-peptide levels. It was considered likely that the neuroendocrine tumour was the source of the insulin secretion. Diazoxide and somatostatin analogue were used to control hypoglycaemia. Much later in the course of the disease, he developed metabolic derangement, increased skin pigmentation and psychological disturbance, without frankly Cushingoid physical findings. Investigations revealed highly elevated cortisol levels (the levels having previously been normal) with markedly raised ACTH levels, consistent with the co-secretion of ACTH and insulin by the tumour. Treatment with metyrapone improved his psychological state and electrolyte imbalance. Unfortunately, despite several cycles of first-, second- and third-line chemotherapy from the start of the first hormonal presentation onwards, imaging revealed widespread progressive metastatic disease and the patient eventually passed away. This case highlights the importance of keeping in mind the biochemical heterogeneity of endocrine tumours during their treatment. Learning points The clinical presentation of insulin-secreting tumours includes symptoms of neuroglycopaenia and sympathetic overstimulation.Tumour-associated hypoglycaemia can be due to pancreatic insulinomas, and although ectopic hormone production occurs in a number of tumours, ectopic secretion of insulin is rare.A possible switch in the type of hormone produced can occur during the growth and progression of neuroendocrine tumours and, when treating neuroendocrine tumours, it is important to keep in mind their biochemical heterogeneity. PMID:24683485

  18. Cushing's syndrome secondary to ectopic ACTH secretion: The University of Texas MD Anderson Cancer Center Experience

    PubMed Central

    Ejaz, Shamim; Vassilopoulou-Sellin, Rena; Busaidy, Naifa L.; Hu, Mimi I.; Waguespack, Steven G.; Jimenez, Camilo; Ying, Anita K.; Cabanillas, Maria; Abbara, Maher; Habra, Mouhammed Amir

    2011-01-01

    Background Cushing's syndrome (CS) secondary to ectopic ACTH secretion (EAS) has been described in association with a variety of tumors. The current experience with this syndrome is based on a few case series and individual case reports. Limited data are available about the tumors associated with CS-EAS in cancer center setting. This report describes CS-EAS at MD Anderson Cancer Center to further enhance our understanding and management of this syndrome. Methods This is a retrospective review for 43 patients with CS-EAS who were diagnosed between 1979 and 2009 at our institution. Results Different neuroendocrine tumors were associated with CS-EAS. Twenty one patients (48.9%) had tumors located in the chest cavity with bronchial carcinoid and small cell lung cancer representing the two most common causes. The ACTH source remained occult in 4 patients (9.3 %) despite extensive work-up. Clinical presentation was variable and the classical features of CS were not evident in some patients. Death occurred in 27 patients (62.8%) and the median overall survival was 32.2 months. Major morbidities included new onset or worsening hyperglycemia (77%), symptomatic venous thromboembolism (14%) and infections (23%). Conclusions In CS-EAS cases seen at a comprehensive cancer center, tumors originating in the chest cavity were the leading tumors associated with this syndrome. We suspect that CS-EAS is underreported because of the atypical presentation in some cases. Thus, we suggest careful evaluation of patients with neuroendocrine tumors to avoid missing co-existing CS-EAS. PMID:21412758

  19. Ewes With Divergent Cortisol Responses to ACTH Exhibit Functional Differences in the Hypothalamo-Pituitary-Adrenal (HPA) Axis.

    PubMed

    Hewagalamulage, Sakda D; Clarke, Iain J; Rao, Alexandra; Henry, Belinda A

    2016-09-01

    Within any population, the cortisol response to ACTH covers a considerable range. High responders (HRs) exhibit a greater cortisol secretory response to stress or ACTH, compared with individuals classified as low cortisol responders (LRs). We administered ACTH (0.2 μg/kg, iv) to 160 female sheep and selected subpopulations of animals as LR and HR. In the present study, we aimed to characterize the hypothalamo-pituitary-adrenal axis in HR and LR and to identify factors that underlie the differing cortisol responses to ACTH. Hypothalami, pituitaries, and adrenals were collected from nonstressed HR and LR ewes. Expression of genes for CRH, arginine vasopressin (AVP), oxytocin, glucocorticoid receptor, and mineralocorticoid receptor were measured by in situ hybridization in the paraventricular nucleus of the hypothalamus, and proopiomelanocortin (POMC) gene expression was measured in the anterior pituitary. Expression of CRH, AVP, and POMC was higher in HR, with no differences in either glucocorticoid receptor or mineralocorticoid receptor expression. Oxytocin expression was greater in LR. In the adrenal gland, real-time PCR analysis indicated that expression of the ACTH receptor and a range of steroidogenic enzymes was similar in HR and LR. Adrenal weights, the cortex to medulla ratio and adrenal cortisol content were also similar in LR and HR. In conclusion, LR and HR display innate differences in the steady-state expression of CRH, AVP, oxytocin, and POMC, indicating that selection for cortisol responsiveness identifies distinct subpopulations that exhibit innate differences in the gene expression/function of hypothalamo-pituitary-adrenal axis markers. PMID:27414744

  20. Analysis of ACTH-related and CLIP-related peptides partially purified from the pituitary of the Australian lungfish, Neoceratodus forsteri.

    PubMed

    Dores, R M; Adamczyk, D L; Joss, J M

    1990-07-01

    Acid extracts of individual lungfish pituitaries were fractionated by gel filtration on a Sephadex G-75 column and aliquots of column fractions were screened with a heterologous ACTH(1-39) radioimmunoassay (RIA). Two major, incompletely separated, peaks of ACTH-related immunoreactivity were detected. These peaks of ACTH-related material were resolved by reverse-phase high-performance liquid chromatography and were designated Peak A and Peak B. Peak A had a retention time more hydrophilic than synthetic human CLIP [ACTH(18-39)], whereas Peak B had a retention time similar to, but not identical with, human ACTH(1-39). Further analysis indicated that Peak A had an apparent molecular weight of 2.5K and an isoelectric point of 4.3. Based on these characteristics, Peak A would appear to be lungfish CLIP. Peak B had an apparent molecular weight of 4.5K. Based on chromatographic and immunological properties, Peak B would appear to be lungfish ACTH. The detection of these lungfish peptides by heterologous RIA indicates a high degree of primary sequence homology between lungfish and tetrapod ACTH-related polypeptides.

  1. Paraventricular Stimulation with Glutamate Elicits Bradycardia and Pituitary Responses

    NASA Technical Reports Server (NTRS)

    Darlington, Daniel N.; Miyamoto, Michael; Keil, Lanny C.; Dallman, Mary F.

    1989-01-01

    The excitatory neurotransmitter, L-glutamate (0.5 M, pH 7.4), or the organic acid, acetate (0.5 M, pH 7.4), was microinjected (50 nl over 2 min) directly into the paraventricular nuclei (PVN) of pentobarbital sodium-anesthetized rats while arterial blood pressure and heart rate and plasma adrenocorticotropic hormone (ACTH), vasopressin, and oxytocin were measured. Activation of PVN neurons with L-glutamate led to increases in plasma ACTH, vasopressin, and oxytocin and a profound bradycardia (-80 beats/min) with little change in arterial blood pressure. Microinjection of acetate had no effect on the above variables. The decrease in heart rate was shown to be dependent on the concentration of glutamate injected and the volume of injectate. The bradycardia was mediated through the autonomic nervous system because ganglionic blockade (pentolinium tartrate) eliminated the response; atropine and propranolol severely attenuated the bradycardia. The bradycardia was greatest when L-glutamate was microinjected into the caudal PVN. Injections into the rostral PVN or into nuclei surrounding the PVN led to small or nonsignificant decreases in heart rate. Focal electric stimulation (2-50 pA) of the PVN also led to decreases in heart rate and arterial blood pressure. These data suggest that activation of PVN neurons leads to the release of ACTH, vasopressin, and oxytocin from the pituitary and a bradycardia that is mediated by the autonomic nervous system.

  2. ACTH administration during formation of preovulatory follicles impairs steroidogenesis and angiogenesis in association with ovulation failure in lactating cows.

    PubMed

    Biran, D; Braw-Tal, R; Gendelman, M; Lavon, Y; Roth, Z

    2015-10-01

    Ovulation failure, follicular persistence, and formation of follicular cysts are known to impair dairy cow fertility. Although the underlying mechanism is not entirely clear, stress-induced alteration in adrenal hormone secretion can cause these ovarian pathologies. Six synchronized lactating cows were scanned daily by ultrasound, and plasma samples were taken throughout the estrous cycle. Treatment cows (n = 3) were administered with ACTH analog every 12 h from day 15 to day 21 of the cycle to induce formation of follicular cysts. Ovaries were collected at the slaughterhouse on day 23 of the cycle before appearance of follicular pathologies. Control cows (n = 3) were administered placebo, resynchronized, and administered PGF2α on day 6 of the new cycle to induce development of a preovulatory follicle. Follicular fluid was aspirated from the preovulatory follicles of each group to determine their steroid milieu. Slices were taken from the follicular wall for total messenger (m) RNA isolation and semiquantitative reverse transcription polymerase chain reaction (RT-PCR). Administration of ACTH increased (P < 0.02) plasma cortisol concentration and reduced (P < 0.01) milk production. Androstenedione and estradiol concentrations in the follicular fluids were lower (P < 0.05) in ACTH-treated follicles than those in controls. The mRNA expression of luteinizing hormone receptor, 3β-hydroxysteroid dehydrogenase, cytochrome P450 aromatase (P450arom), and cytochrome P450 17α-hydroxylase (P450c17) were lower (P < 0.02) in the ACTH-treated vs control cows. On the other hand, the expression of steroidogenic acute regulatory protein and cytochrome P450 side-chain cleavage did not differ between groups. In addition, mRNA expression of vascular endothelial growth factor (VEGF)120 and VEGF164 was higher (P < 0.01) in control than in ACTH-treated follicles, but that for angiopoietin-1 and 2 did not differ between groups. Findings indicated that ACTH administration throughout

  3. Metabolic effects of cortisol, ACTH, adrenalin and insulin in the marsupial sugar glider, Petaurus breviceps.

    PubMed

    Bradley, A J; Stoddart, D M

    1990-11-01

    The effects of cortisol, ACTH, adrenalin and insulin on indices of carbohydrate, fat and protein metabolism were investigated in the conscious marsupial sugar glider Petaurus breviceps. Short-term i.v. infusion of cortisol at dose rates of 0.02, 0.2 and 1.0 mg/kg per h caused the plasma glucose concentration to rise sharply from the normal range of 3.3-4.4 to 8.1-8.7 mmol/l at the end of the infusion period without significant alteration in plasma free fatty acid (FFA), amino acid or urea concentrations. Infusions of ACTH at dose rates of 0.02, 0.06 and 0.45 IU/kg per h caused a similar rise in plasma glucose concentration; however, this was now accompanied by an elevation in plasma FFA concentration, but again without significant changes in either plasma amino acid or urea concentrations. Infusion of adrenalin at 10 micrograms/kg per h caused an increase in the plasma concentrations of both glucose and FFA. Intravenous injections of 0.15 IU insulin/kg caused a rapid and marked decrease in the plasma glucose concentration within 30 min and an increase in the plasma free cortisol concentration. Associated with this change was a marked rise in the plasma concentration of both FFA and free cortisol. The rise in free cortisol was, however, significantly reduced by infusion of glucose. Pretreatment with five daily i.m. injections of 1 mg cortisol acetate/kg, which produced an increase in plasma free cortisol concentration to near the maximum of the physiological range, caused a marked reduction in insulin sensitivity. Cortisol pretreatment caused an increase in the plasma FFA and amino acid concentrations. Petaurus breviceps is highly sensitive to the metabolic effects of glucocorticoids and is similar in this respect to the brush-tailed possum Trichosurus vulpecula. The interactive effects between insulin and glucocorticoids on carbohydrate, fat and protein metabolism in Petaurus breviceps are similar to those shown by Trichosurus vulpecula and some eutherian mammals

  4. Metabolic effects of cortisol, ACTH, adrenalin and insulin in the marsupial sugar glider, Petaurus breviceps.

    PubMed

    Bradley, A J; Stoddart, D M

    1990-11-01

    The effects of cortisol, ACTH, adrenalin and insulin on indices of carbohydrate, fat and protein metabolism were investigated in the conscious marsupial sugar glider Petaurus breviceps. Short-term i.v. infusion of cortisol at dose rates of 0.02, 0.2 and 1.0 mg/kg per h caused the plasma glucose concentration to rise sharply from the normal range of 3.3-4.4 to 8.1-8.7 mmol/l at the end of the infusion period without significant alteration in plasma free fatty acid (FFA), amino acid or urea concentrations. Infusions of ACTH at dose rates of 0.02, 0.06 and 0.45 IU/kg per h caused a similar rise in plasma glucose concentration; however, this was now accompanied by an elevation in plasma FFA concentration, but again without significant changes in either plasma amino acid or urea concentrations. Infusion of adrenalin at 10 micrograms/kg per h caused an increase in the plasma concentrations of both glucose and FFA. Intravenous injections of 0.15 IU insulin/kg caused a rapid and marked decrease in the plasma glucose concentration within 30 min and an increase in the plasma free cortisol concentration. Associated with this change was a marked rise in the plasma concentration of both FFA and free cortisol. The rise in free cortisol was, however, significantly reduced by infusion of glucose. Pretreatment with five daily i.m. injections of 1 mg cortisol acetate/kg, which produced an increase in plasma free cortisol concentration to near the maximum of the physiological range, caused a marked reduction in insulin sensitivity. Cortisol pretreatment caused an increase in the plasma FFA and amino acid concentrations. Petaurus breviceps is highly sensitive to the metabolic effects of glucocorticoids and is similar in this respect to the brush-tailed possum Trichosurus vulpecula. The interactive effects between insulin and glucocorticoids on carbohydrate, fat and protein metabolism in Petaurus breviceps are similar to those shown by Trichosurus vulpecula and some eutherian mammals

  5. A novel mutation of the adrenocorticotropin receptor (ACTH-R) gene in a family with the syndrome of isolated glucocorticoid deficiency, but no ACTH-R abnormalities in two families with the triple A syndrome

    SciTech Connect

    Tsigos, C.; Arai, K.; Latronico, A.C. ||

    1995-07-01

    Isolated glucocorticoid deficiency (IGD) is an autosomal recessive disorder characterized by primary adrenocortical insufficiency, usually without mineralocorticoid deficiency. Occasionally, the disorder is associated with alacrima and achalasia of the esophagus (triple A syndrome), suggesting potential heterogeneity in its etiology. Mutations in the ACTH receptor gene have been reported in several families with IGD. We have amplified and directly sequenced the entire intronless ACTH receptor gene in 1 other family with IGD and 2 famlies with triple A syndrome. The proband with IGD was a homozygote for an A {r_arrow}G substitution, changing tyrosine 254 to cysteine in the third extracellular loop of the receptor protein, probably interfering with ligand binding. Both of her parents were heterozygotes for this mutation, which was not detected in 100 normal alleles. No mutations were identified in the entire coding area of the ACTH receptor in the 2 families with triple A syndrome, supporting the idea of a developmental or postreceptor defect in this syndrome. 19 refs., 1 fig.

  6. Growth hormone response to a growth hormone-releasing hormone stimulation test in a population-based study following cranial irradiation of childhood brain tumors.

    PubMed

    Schmiegelow, M; Lassen, S; Poulsen, H S; Feldt-Rasmussen, U; Schmiegelow, K; Hertz, H; Müller, J

    2000-01-01

    Children with brain tumors are at high risk of developing growth hormone deficiency (GHD) after cranial irradiation (CI) if the hypothalamus/pituitary (HP) axis falls within the fields of irradiation. The biological effective dose (BED) of irradiation to the HP region was determined, since BED gives a means of expressing the biological effect of various irradiation treatment schedules in a uniform way. Hypothalamic versus pituitary damage as cause of GHD was distinguished in 62 patients by comparing the growth hormone (GH) peak response to an insulin tolerance test (ITT)/arginine stimulation test and the GH response to a growth hormone-releasing hormone (GHRH) stimulation test. Peak GH response to a GHRH test was significantly higher (median 7.3 mU/l; range: 0.5--79.0 mU/l) than that of an ITT/arginine test (median 4.7 mU/l; range: 0.01--75.0 mU/l) (p = 0.017). Peak GH after a GHRH test was significantly inversely correlated to follow-up time (r(s) = -0.46, p < 0.0001) and to BED (R(s) = -0.28, p = 0.03), and both were found to be of significance in a multivariante regression analysis. We speculate that a significant number of patients developed hypothalamic radiation-induced damage to the GHRH secreting neurons, and secondary to this the pituitary gland developed decreased responsiveness to GHRH following CI in childhood.

  7. Blood supply to the brain and. beta. -endorphin and acth levels under the influence of thyrotrophin releasing hormone

    SciTech Connect

    Mirzoyan, R.S.; Ganshina, T.S.; Mirzoyan, R.A.; Ragimov, K.S.

    1985-08-01

    The authors studied beta-endorphin because of its possible mediator role in terms of the cerebrovascular effects of thyrotrophin releasing hormone (TRH), and also because of data in the literature on antagonistic relations between TRH and the endogenous opioid system of the brain. Beta-endorphin was determined by radioimmunoassay; its level was determined after its separation from the beta-lipotrophin fraction. The investigation showed that TRH has a marked depressant effect on cerebrovascular vasoconstrictor refleces. Elevation of the blood ACTH level causes an increase in BP and in the tone of the cerebral vessels. An absence of correlation between the beta-endorphin and ACTH levels in the blood and CSF under the influence of TRH is shown.

  8. Changes in the hormone (ACTH, insulin,epinephrine) content of immune cells in children having acute lymphocytic leukemia (ALL).

    PubMed

    Pállinger, Eva; Kovács, Gábor; Horváth, Zsuzsanna; Müller, Judit; Csaba, György

    2013-12-01

    Immune cells synthesize, store and secrete hormones, the level of which changes in ALL. In previous experiments the level of histamine, serotonin and triiodothyronine (T3)was studied, while at present that of ACTH, insulin and epinephrine, using flow cytometric analysis for the determination of cell subsets and detection of hormone content. The measurements were done in children at the time of diagnosis. ACTH was significantly elevated in each T cell subsets (total T, Th, Tc, activated T), while B and NK cells were not touched. The alterations in the insulin content (decrease in Tc and activated T cells) were uncertain, and NK cells contained significantly less insulin. The disease did not influence the cells' epinephrine content. There is not clear explanation for the importance of changes in the cells' hormone content, however, it is discussed in the text.

  9. The value of prolactin in inferior petrosal sinus sampling with desmopressin stimulation in Cushing's disease.

    PubMed

    Qiao, Xiaona; Ye, Hongying; Zhang, Xiaolong; Zhao, Weiwei; Zhang, Shuo; Lu, Bin; Wang, Xuanchun; Zhang, Zhaoyun; Wu, Xi; He, Min; Zhao, Xiaolong; Li, Shiqi; Zhou, Linuo; Yang, Yehong; Hu, Renming; Li, Yiming

    2015-03-01

    Prolactin may reduce false-negative results in diagnosing Cushing's disease (CD) during inferior petrosal sinus sampling (IPSS). Prolactin normalization could improve the accuracy of IPSS in predicting adenoma lateralization in CD. However, none of the previous studies had involved the use of desmopressin during IPSS. Our objective was to examine the utility of prolactin measurement during IPSS with desmopressin stimulation. We conducted a retrospective analysis of 40 patients (including 31 females) with ACTH-dependent Cushing's syndrome who underwent IPSS between 2010 and 2013. Thirty-eight CD patients were partitioned into true positive (n = 35) and false negative (n = 3). The proportion of improper IPSS venous sampling defined by corresponding IPS:P (inferior petrosal sinus to peripheral) prolactin ratio <1.8 was significantly different between two groups (P = 0.004). Applying a prolactin-normalized ACTH IPS:P ratio >0.8 cutoff could increase the sensitivity of IPSS to 38/38 (100 %). Among the 31 patients with histopathologically proven adenoma localization, correct prediction of adenoma lateralization was obtained in 14/31 (45 %) patients by a peak intersinus ACTH gradient of ≥1.4 in baseline and was not improved by desmopressin stimulation. Left-right intersinus gradients of unilateral prolactin-adjusted ACTH IPS:P ratios could increase the correct prediction of adenoma lateralization to 20/31 (65 %) in baseline and 24/31 (77 %) (P = 0.006) after desmopressin stimulation, respectively. Prolactin is helpful to adjust negative results of IPSS with desmopressin stimulation. It may improve the accuracy in predicting adenoma lateralization in CD as well.

  10. A synthetic stimulant never tested in humans, 1,3-dimethylbutylamine (DMBA), is identified in multiple dietary supplements.

    PubMed

    Cohen, Pieter A; Travis, John C; Venhuis, Bastiaan J

    2015-01-01

    A synthetic stimulant never before studied in humans, 1,3-dimethylbutylamine (DMBA), was suspected of being present in dietary supplements. DMBA is an analogue of the pharmaceutical stimulant, 1,3-dimethylamylamine (DMAA), which was recently banned by the US Food and Drug Administration. We obtained all dietary supplements sold by US distributors that listed an ingredient on the label, such as AMP Citrate, that might be a marketing name for DMBA. Supplements were analyzed for the presence and quantity of DMBA. Fourteen supplements met our inclusion criteria and were analyzed by two separate laboratories using ultra high performance liquid chromatography (UHPLC) - mass spectrometry and a reference standard. The identity of DMBA was confirmed in 12 supplements in the range of 13 to 120 mg DMBA per serving. Following recommendations on the supplement label for maximum daily intake, customers would consume from 26 to 320 mg of DMBA per day. Supplements containing DMBA were marketed to improve athletic performance, increase weight loss and enhance brain function. DMBA has never before been detected in supplements. The stimulant has never been studied in humans; its efficacy and safety are entirely unknown. Regulatory agencies should act expeditiously to warn consumers and remove DMBA from all dietary supplements.

  11. Drilling, completion, stimulation, and testing of BDM/CNGD Well 3997, Lee District, Calhoun County, West Virginia. Final report

    SciTech Connect

    Overbey, W.K. Jr.; Carden, R.S.; Salamy, S.P.; Locke, C.D.; Johnson, H.R.

    1992-03-01

    This report discusses the detailed field operations in drilling, casing, completing, and stimulating the Hunter Bennett No. 3997 well located in Lee District, Calhoun County West Virginia. The project was designed and managed by BDM in cooperation with CNG Development Company. The well was spudded on November 9, 1990, and drilling was completed on December 14, 1990. The well was drilled on an average asmuth of 312 degrees with a total horizontal displacement of 2459 feet. The well was turned to a 90 degree inclination from the vertical over a measured course length of 1216 feet. Approximately 1381 feet of the well had an inclination higher than 86 degrees, while 2179 feet had an inclination greater than 62 degrees. The well was partitioned into five zones for stimulation purposes. Each zone is a little more than 300 feet long. The well was stimulated with nitrogen gas in zones one and two. Early production results are encouraging. The BDM/CNGD horizontal well averaged 147 mcfd of gas over the first week of production and, in week five, began to produce oil at a rate of about 2 bbl/day.

  12. Drilling, completion, stimulation, and testing of BDM/CNGD Well 3997, Lee District, Calhoun County, West Virginia

    SciTech Connect

    Overbey, W.K. Jr.; Carden, R.S.; Salamy, S.P.; Locke, C.D.; Johnson, H.R.

    1992-03-01

    This report discusses the detailed field operations in drilling, casing, completing, and stimulating the Hunter Bennett No. 3997 well located in Lee District, Calhoun County West Virginia. The project was designed and managed by BDM in cooperation with CNG Development Company. The well was spudded on November 9, 1990, and drilling was completed on December 14, 1990. The well was drilled on an average asmuth of 312 degrees with a total horizontal displacement of 2459 feet. The well was turned to a 90 degree inclination from the vertical over a measured course length of 1216 feet. Approximately 1381 feet of the well had an inclination higher than 86 degrees, while 2179 feet had an inclination greater than 62 degrees. The well was partitioned into five zones for stimulation purposes. Each zone is a little more than 300 feet long. The well was stimulated with nitrogen gas in zones one and two. Early production results are encouraging. The BDM/CNGD horizontal well averaged 147 mcfd of gas over the first week of production and, in week five, began to produce oil at a rate of about 2 bbl/day.

  13. An integrated interface for peripheral neural system recording and stimulation: system design, electrical tests and in-vivo results.

    PubMed

    Carboni, Caterina; Bisoni, Lorenzo; Carta, Nicola; Puddu, Roberto; Raspopovic, Stanisa; Navarro, Xavier; Raffo, Luigi; Barbaro, Massimo

    2016-04-01

    The prototype of an electronic bi-directional interface between the Peripheral Nervous System (PNS) and a neuro-controlled hand prosthesis is presented. The system is composed of 2 integrated circuits: a standard CMOS device for neural recording and a HVCMOS device for neural stimulation. The integrated circuits have been realized in 2 different 0.35μ m CMOS processes available from ams. The complete system incorporates 8 channels each including the analog front-end, the A/D conversion, based on a sigma delta architecture and a programmable stimulation module implemented as a 5-bit current DAC; two voltage boosters supply the output stimulation stage with a programmable voltage scalable up to 17V. Successful in-vivo experiments with rats having a TIME electrode implanted in the sciatic nerve were carried out, showing the capability of recording neural signals in the tens of microvolts, with a global noise of 7μ V r m s , and to selectively elicit the tibial and plantar muscles using different active sites of the electrode. PMID:27007860

  14. Metabolic responses to adrenocorticotropic hormone (ACTH) vary with life-history stage in adult male northern elephant seals.

    PubMed

    Ensminger, David C; Somo, Derek A; Houser, Dorian S; Crocker, Daniel E

    2014-08-01

    Strong individual and life-history variation in serum glucocorticoids has been documented in many wildlife species. Less is known about variation in hypothalamic-pituitary-adrenal (HPA) axis responsiveness and its impact on metabolism. We challenged 18 free-ranging adult male northern elephant seals (NES) with an intramuscular injection of slow-release adrenocorticotropic hormone (ACTH) over 3 sample periods: early in the breeding season, after 70+ days of the breeding fast, and during peak molt. Subjects were blood sampled every 30 min for 2h post-injection. Breeding animals were recaptured and sampled at 48 h. In response to the ACTH injection, cortisol increased 4-6-fold in all groups, and remained elevated at 48 h in early breeding subjects. ACTH was a strong secretagogue for aldosterone, causing a 3-8-fold increase in concentration. Cortisol and aldosterone responses did not vary between groups but were correlated within individuals. The ACTH challenge produced elevations in plasma glucose during late breeding and molting, suppressed testosterone and thyroid hormone at 48 h in early breeding, and increased plasma non-esterified fatty acids and ketoacids during molting. These data suggest that sensitivity of the HPA axis is maintained but the metabolic impacts of cortisol and feedback inhibition of the axis vary with life history stage. Strong impacts on testosterone and thyroid hormone suggest the importance of maintaining low cortisol levels during the breeding fast. These data suggest that metabolic adaptations to extended fasting in NES include alterations in tissue responses to hormones that mitigate deleterious impacts of acute or moderately sustained stress responses.

  15. Metabolic responses to adrenocorticotropic hormone (ACTH) vary with life-history stage in adult male northern elephant seals.

    PubMed

    Ensminger, David C; Somo, Derek A; Houser, Dorian S; Crocker, Daniel E

    2014-08-01

    Strong individual and life-history variation in serum glucocorticoids has been documented in many wildlife species. Less is known about variation in hypothalamic-pituitary-adrenal (HPA) axis responsiveness and its impact on metabolism. We challenged 18 free-ranging adult male northern elephant seals (NES) with an intramuscular injection of slow-release adrenocorticotropic hormone (ACTH) over 3 sample periods: early in the breeding season, after 70+ days of the breeding fast, and during peak molt. Subjects were blood sampled every 30 min for 2h post-injection. Breeding animals were recaptured and sampled at 48 h. In response to the ACTH injection, cortisol increased 4-6-fold in all groups, and remained elevated at 48 h in early breeding subjects. ACTH was a strong secretagogue for aldosterone, causing a 3-8-fold increase in concentration. Cortisol and aldosterone responses did not vary between groups but were correlated within individuals. The ACTH challenge produced elevations in plasma glucose during late breeding and molting, suppressed testosterone and thyroid hormone at 48 h in early breeding, and increased plasma non-esterified fatty acids and ketoacids during molting. These data suggest that sensitivity of the HPA axis is maintained but the metabolic impacts of cortisol and feedback inhibition of the axis vary with life history stage. Strong impacts on testosterone and thyroid hormone suggest the importance of maintaining low cortisol levels during the breeding fast. These data suggest that metabolic adaptations to extended fasting in NES include alterations in tissue responses to hormones that mitigate deleterious impacts of acute or moderately sustained stress responses. PMID:24798580

  16. Postovulatory effect of repeated intravenous administration of ACTH on the contractile activity of the oviduct, ova transport and endocrine status of recently ovulated and unrestrained sows.

    PubMed

    Mwanza, A M; Madej, A; Kindahl, H; Lundeheim, N; Einarsson, S

    2000-11-01

    The effect of repeated intravenous administration of ACTH (Synacthen depot) on the contractile activity of the oviduct, ova transport and endocrine status was studied in 11 Swedish crossbred (Landrace x Yorkshire) multiparous sows. In the second estrus after weaning, the ACTH group (Group A, n=6) sows were administered 0.01 mg/kg body weight of ACTH every 6 h commencing 4 to 8 h after ovulation, whereas the control group (Group C, n=5) sows were administered saline solution. Immediately after standing estrus, a Millar pressure transducer was placed about 3 cm into the isthmus via a laparotomy. Blood samples for hormonal analyses and pressure recordings of the oviduct were collected from all sows until slaughter. After slaughter, the genital tract opposite to the side with the transducer was retrieved, and 3 equal isthmic segments and the first third of the uterine horn portion adjacent to the UTJ were flushed separately for ova recovery. Cortisol levels were significantly (P<0.05) elevated after ACTH administration. Progesterone and PGF2alpha metabolite levels were significantly (P<0.05) elevated only after the first ACTH administration. No significant differences (P>0.05) were seen in the mean pressure and frequencies of phasic pressure fluctuations either before or after every ACTH administration between Groups A and C. No significant difference (P>0.05) was seen in the proportion of ova recovered in the different segments between Groups A and C. It can be concluded from the present study that the administration of ACTH (0.01 mg/kg body weight) to sows at 4 to 8 h after ovulation, and after each subsequent ACTH administration, elevates cortisol levels, whereas progesterone and PGF2alpha metabolite levels are elevated only after the first treatment, and that this has no effect on the mean isthmic pressure, the frequency of phasic pressure fluctuations or ova transport. PMID:11192189

  17. Treatment of iatrogenic Cushing's syndrome in dogs with electroacupuncture stimulation of stomach 36.

    PubMed

    Lin, J H; Su, H L; Chang, S H; Shien, Y S; Wu, L S

    1991-01-01

    This study was conducted to evaluate the effectiveness of electroacupuncture (EA) on the recovery of adrenocortical function from Iatrogenic Cushings Syndrome (ICS) in dogs. Experiment I: Selection of the most effective Acupuncture point to treat ICS--Six healthy adult female dogs were treated bilaterally with EA for 15 minutes at loci BL22 + BL23 + BL24, ST36, or a non-locus control point on M. brachialis. Each dog was tested at all three sites in rotation. Blood samples were collected before and 0, 15 and 60 minutes after EA, and the serum cortisol levels were measured by radioimmunoassay. The data showed that EA at ST36 resulted in the highest response of serum cortisol levels among the three treatments. Experiment II: Evaluation of the effectiveness of EA ST36 in the treatment of ICS in dogs--Eight healthy adult female dogs were given prednisolone acetate 2mg/kg/day IM for 3 weeks. They were then randomly divided into ST36 and control groups of 4 dogs each. In the ST36 group, ST36 was treated bilaterally with EA for 30 minutes, 3 times per week, for 3 consecutive weeks. For the control, a non-locus point on M. brachialis was treated bilaterally with the same protocol. After the first week of EA, the serum cortisol levels of the ST36 and control groups were 0.9 +/- 0.1 and 0.5 +/- 0.1 micrograms/dl (P less than 0.005) baseline and 2.5 +/- 0.2 and 1.4 +/- 0.4 micrograms/dl (p less than 0.05) and after ACTH stimulation test, respectively. After the third week of EA treatment, the results were 1.0 +/- 0.1 and 0.6 +/- 0.2 micrograms/dl (p less than 0.05) baseline and 4.0 +/- 0.5 and 1.7 +/- 0.5 micrograms/dl (p less than 0.001) after ACTH stimulation respectively. These data indicated that EA at ST36 could restore the adrenocortical hypofunction resulting from ICS in dogs.

  18. Endocrine and immunological responses to adrenocorticotrophic hormone (ACTH) administration in juvenile harbor seals (Phoca vitulina) during winter and summer.

    PubMed

    Keogh, Mandy J; Atkinson, Shannon

    2015-10-01

    There is increasing interest in measuring endocrine and immune parameters in free-ranging seals and sea lions, but there is a lack of understanding in how an acute stress response, often associated with capture and handling, influences these parameters of interest. The main objective of this study was to assess the impact of a simulated stressor on both endocrine and immune parameters. During two seasons, exogenous adrenocorticotrophic hormone (ACTH) was administered to seven female juvenile harbor seals and the response of several hormones (cortisol, aldosterone, total and free thyroxine and total triiodothyronine) and immunological parameters (total and differential leukocyte counts and peripheral blood mononuclear cells (PBMC) proliferation) were assessed. Cortisol peaked at 165 min (winter 203.1±84.7 ng/ml; summer 205.3±65.7 ng/ml) and remained significantly elevated 240 min after ACTH infusion in both seasons. Aldosterone peaked at 90 min (winter 359.3±249.3 pg/ml; summer 294.1±83.7 pg/ml) and remained elevated 240 min after administration of ACTH in both seasons. An increase in circulating total white blood cells was driven primarily by the increase in neutrophils which occurred simultaneously with a decrease in lymphocytes leading to an overall increase in neutrophil to lymphocyte ratio. These findings demonstrate that a simulated stress response in juvenile harbor seals results in a predictable increase in both cortisol and aldosterone concentrations, and were associated with altered immunological parameters.

  19. Endocrine and immunological responses to adrenocorticotrophic hormone (ACTH) administration in juvenile harbor seals (Phoca vitulina) during winter and summer.

    PubMed

    Keogh, Mandy J; Atkinson, Shannon

    2015-10-01

    There is increasing interest in measuring endocrine and immune parameters in free-ranging seals and sea lions, but there is a lack of understanding in how an acute stress response, often associated with capture and handling, influences these parameters of interest. The main objective of this study was to assess the impact of a simulated stressor on both endocrine and immune parameters. During two seasons, exogenous adrenocorticotrophic hormone (ACTH) was administered to seven female juvenile harbor seals and the response of several hormones (cortisol, aldosterone, total and free thyroxine and total triiodothyronine) and immunological parameters (total and differential leukocyte counts and peripheral blood mononuclear cells (PBMC) proliferation) were assessed. Cortisol peaked at 165 min (winter 203.1±84.7 ng/ml; summer 205.3±65.7 ng/ml) and remained significantly elevated 240 min after ACTH infusion in both seasons. Aldosterone peaked at 90 min (winter 359.3±249.3 pg/ml; summer 294.1±83.7 pg/ml) and remained elevated 240 min after administration of ACTH in both seasons. An increase in circulating total white blood cells was driven primarily by the increase in neutrophils which occurred simultaneously with a decrease in lymphocytes leading to an overall increase in neutrophil to lymphocyte ratio. These findings demonstrate that a simulated stress response in juvenile harbor seals results in a predictable increase in both cortisol and aldosterone concentrations, and were associated with altered immunological parameters. PMID:26086360

  20. Stimulation of adrenal DNA synthesis in cadmium-treated male rats

    SciTech Connect

    Nishiyama, S.; Nakamura, K.

    1984-07-01

    Cadmium chloride (CdCl2) at a dose of 1 mg/kg body wt was injected into male rats of the Wistar strain, weighing 250 g on the average, twice a day (12-hr intervals) for 7 consecutive days. DNA and RNA contents and (/sup 3/H)-thymidine and (/sup 3/H)-uridine incorporation into the acid-insoluble fraction significantly increased in the adrenals of rats treated with Cd for 2 and 7 consecutive days. Adrenal protein content and weight also significantly increased. These results indicate that continued treatment with Cd stimulates DNA and RNA synthesis in the adrenal cortex, which in turn results in the increase of the total protein contents of the adrenal gland and subsequently in the enlargement of the gland. Serum adrenocorticotrophin (ACTH) and insulin levels in Cd-treated rats were not higher than control levels, suggesting that the stimulation of DNA synthesis in the adrenals of Cd-treated rats is due to factor(s) other than serum ACTH and insulin. Treatment with Cd inhibited DNA synthesis in cultured adrenocortical cells at concentrations of 10(-4) to 10(-8) M, suggesting that Cd does not directly stimulate DNA synthesis in the adrenal gland in vivo. Although the adrenal gland became enlarged, the total adrenal corticosterone content decreased significantly. The decrease of total adrenal corticosterone content may be due to the fall in serum ACTH level of Cd-treated rats.

  1. Development of a dual test procedure for DNA typing and methamphetamine detection using a trace amount of stimulant-containing blood.

    PubMed

    Irii, Toshiaki; Maebashi, Kyoko; Fukui, Kenji; Sohma, Ryoko; Matsumoto, Sari; Takasu, Shojiro; Iwadate, Kimiharu

    2016-05-01

    Investigation of drug-related crimes, such as violation of the Stimulant Drug Control Law, requires identifying the used drug (mainly stimulant drugs, methamphetamine hydrochloride) from a drug solution and the DNA type of the drug user from a trace of blood left in the syringe used to inject the drug. In current standard test procedures, DNA typing and methamphetamine detection are performed as independent tests that use two separate portions of a precious sample. The sample can be entirely used up by either analysis. Therefore, we developed a new procedure involving partial lysis of a stimulant-containing blood sample followed by separation of the lysate into a precipitate for DNA typing and a liquid-phase fraction for methamphetamine detection. The method enables these two tests to be run in parallel using a single portion of sample. Samples were prepared by adding methamphetamine hydrochloride water solution to blood. Samples were lysed with Proteinase K in PBS at 56°C for 20min, cooled at -20°C after adding methanol, and then centrifuged at 15,000rpm. Based on the biopolymer-precipitating ability of alcohol, the precipitate was used for DNA typing and the liquid-phase fraction for methamphetamine detection. For DNA typing, the precipitate was dissolved and DNA was extracted, quantified, and subjected to STR analysis using the AmpFℓSTR® Identifiler® Plus PCR Amplification Kit. For methamphetamine detection, the liquid-phase fraction was evaporated with N2 gas after adding 20μL acetic acid and passed through an extraction column; the substances captured in the column were eluted with a solvent, derivatized, and quantitatively detected using gas chromatograph/mass spectrometry. This method was simple and could be completed in approximately 2h. Both DNA typing and methamphetamine detection were possible, which suggests that this method may be valuable for use in criminal investigations. PMID:27161925

  2. Development of a dual test procedure for DNA typing and methamphetamine detection using a trace amount of stimulant-containing blood.

    PubMed

    Irii, Toshiaki; Maebashi, Kyoko; Fukui, Kenji; Sohma, Ryoko; Matsumoto, Sari; Takasu, Shojiro; Iwadate, Kimiharu

    2016-05-01

    Investigation of drug-related crimes, such as violation of the Stimulant Drug Control Law, requires identifying the used drug (mainly stimulant drugs, methamphetamine hydrochloride) from a drug solution and the DNA type of the drug user from a trace of blood left in the syringe used to inject the drug. In current standard test procedures, DNA typing and methamphetamine detection are performed as independent tests that use two separate portions of a precious sample. The sample can be entirely used up by either analysis. Therefore, we developed a new procedure involving partial lysis of a stimulant-containing blood sample followed by separation of the lysate into a precipitate for DNA typing and a liquid-phase fraction for methamphetamine detection. The method enables these two tests to be run in parallel using a single portion of sample. Samples were prepared by adding methamphetamine hydrochloride water solution to blood. Samples were lysed with Proteinase K in PBS at 56°C for 20min, cooled at -20°C after adding methanol, and then centrifuged at 15,000rpm. Based on the biopolymer-precipitating ability of alcohol, the precipitate was used for DNA typing and the liquid-phase fraction for methamphetamine detection. For DNA typing, the precipitate was dissolved and DNA was extracted, quantified, and subjected to STR analysis using the AmpFℓSTR® Identifiler® Plus PCR Amplification Kit. For methamphetamine detection, the liquid-phase fraction was evaporated with N2 gas after adding 20μL acetic acid and passed through an extraction column; the substances captured in the column were eluted with a solvent, derivatized, and quantitatively detected using gas chromatograph/mass spectrometry. This method was simple and could be completed in approximately 2h. Both DNA typing and methamphetamine detection were possible, which suggests that this method may be valuable for use in criminal investigations.

  3. Management of occult adrenocorticotropin-secreting bronchial carcinoids: limits of endocrine testing and imaging techniques.

    PubMed

    Loli, P; Vignati, F; Grossrubatscher, E; Dalino, P; Possa, M; Zurleni, F; Lomuscio, G; Rossetti, O; Ravini, M; Vanzulli, A; Bacchetta, C; Galli, C; Valente, D

    2003-03-01

    The differential diagnosis and the identification of the source of ACTH in occult ectopic Cushing's syndrome due to a bronchial carcinoid still represents a challenge for the endocrinologist. We report our experience in six patients with occult bronchial carcinoid in whom extensive hormonal, imaging, and scintigraphic evaluation was performed. All patients presented with hypercortisolism associated with high plasma ACTH values. The CRH test and high dose dexamethasone suppression test suggested an ectopic source of ACTH in three of six patients. During bilateral inferior petrosal sinus sampling, none of the patients showed a central to peripheral ACTH gradient. At the time of diagnosis, none of the patients had radiological evidence of the ectopic source of ACTH, whereas pentetreotide scintigraphy identified the lesion in two of four patients. Finally, a chest computed tomography scan revealed the presence of a bronchial lesion in all patients, and pentetreotide scintigraphy identified four of six lesions. In all patients a bronchial carcinoid was found and removed. In one patient with scintigraphic evidence of residual disease after two operations, radioguided surgery, using a hand-held gamma probe after iv administration of radiolabeled pentetreotide, was performed; this allowed detection and removal of residual multiple mediastinal lymph node metastases. In conclusion, our data show that there is not a single endocrine test or imaging procedure accurate enough to diagnose and localize occult ectopic ACTH-secreting bronchial carcinoids. Radioguided surgery appears to be promising in the presence of multiple tumor foci and previous incomplete removal of the tumor. PMID:12629081

  4. Management of occult adrenocorticotropin-secreting bronchial carcinoids: limits of endocrine testing and imaging techniques.

    PubMed

    Loli, P; Vignati, F; Grossrubatscher, E; Dalino, P; Possa, M; Zurleni, F; Lomuscio, G; Rossetti, O; Ravini, M; Vanzulli, A; Bacchetta, C; Galli, C; Valente, D

    2003-03-01

    The differential diagnosis and the identification of the source of ACTH in occult ectopic Cushing's syndrome due to a bronchial carcinoid still represents a challenge for the endocrinologist. We report our experience in six patients with occult bronchial carcinoid in whom extensive hormonal, imaging, and scintigraphic evaluation was performed. All patients presented with hypercortisolism associated with high plasma ACTH values. The CRH test and high dose dexamethasone suppression test suggested an ectopic source of ACTH in three of six patients. During bilateral inferior petrosal sinus sampling, none of the patients showed a central to peripheral ACTH gradient. At the time of diagnosis, none of the patients had radiological evidence of the ectopic source of ACTH, whereas pentetreotide scintigraphy identified the lesion in two of four patients. Finally, a chest computed tomography scan revealed the presence of a bronchial lesion in all patients, and pentetreotide scintigraphy identified four of six lesions. In all patients a bronchial carcinoid was found and removed. In one patient with scintigraphic evidence of residual disease after two operations, radioguided surgery, using a hand-held gamma probe after iv administration of radiolabeled pentetreotide, was performed; this allowed detection and removal of residual multiple mediastinal lymph node metastases. In conclusion, our data show that there is not a single endocrine test or imaging procedure accurate enough to diagnose and localize occult ectopic ACTH-secreting bronchial carcinoids. Radioguided surgery appears to be promising in the presence of multiple tumor foci and previous incomplete removal of the tumor.

  5. Test-Retest Reliability of 10 Hz Conditioning Electrical Stimulation Inducing Long-Term Potentiation (LTP)-Like Pain Amplification in Humans

    PubMed Central

    Xia, Weiwei; Mørch, Carsten Dahl; Andersen, Ole Kæseler

    2016-01-01

    Background 10 Hz conditioning electrical stimulation (CES) has been shown to induce long-term potentiation (LTP)-like pain amplification similar to traditional 100 Hz CES in healthy humans. The aim of this study was to assess the test-retest reliability and to estimate sample sizes required for future crossover and parallel study designs. Methods The 10 Hz paradigm (500 rectangular pulses lasting 50 s) was repeated on two separate days with one week interval in twenty volunteers. Perceptual intensities to single electrical stimulation (SES) at the conditioned skin site and to mechanical stimuli (pinprick and light stroking) in immediate vicinity to the conditioned skin site were recorded. Superficial blood flow (SBF) was assessed as indicator of neurogenic inflammation. All outcome measures were assessed with 10 min interval three times before and six times after the CES. The coefficient of variation and intra-class correlation coefficient were calculated within session and between sessions. Sample sizes were estimated for future crossover (Ncr) and parallel (Np) drug testing studies expected to detect a 30% decrease for the individual outcome measure following 10 Hz CES. Results Perceptual intensity ratings to light stroking (Ncr = 2, Np = 33) and pinprick stimulation (491 mN) (Ncr = 6, Np = 54) increased after CES and showed better reliability in crossover than parallel design. The SBF increased after CES, and then declined until reaching a plateau 20 minutes postCES. SBF showed acceptable reliability both in crossover and parallel designs (Ncr = 3, Np = 13). Pain ratings to SES were reliable, but with large estimated sample sizes (Ncr = 634, Np = 11310) due to the minor pain amplification. Conclusions The reliability of 10 Hz CES was acceptable in inducing LTP-like effects in the assessments of superficial blood flow, heterotopic mechanical hyperalgesia, and dysesthesia in terms of sample sizes for future crossover study designs. PMID:27529175

  6. Use of whole blood lymphocyte stimulation test for immunocompetency studies in bald eagles, red-tailed hawks, and great horned owls.

    PubMed

    Redig, P T; Dunnette, J L; Sivanandan, V

    1984-11-01

    Mitogen-induced whole blood lymphocyte stimulation tests for immunocompetency studies in bald eagles (Haliaeetus leucocephalus), red-tailed hawks (Buteo jamaicensis), and great horned owls (Bubo virginianus) were developed. Combinations of incubation times, blood dilutions, concentrations of [3H]thymidine and [125I]2-deoxyuridine, antibiotics, phytohemagglutinin-P, and concanavalin A were tested for their effects on the stimulation index (SI). An antibiotic combination of gentamicin plus amphotericin B yielded low SI with lymphocytes from bald eagles, but not with lymphocytes from great horned owls or red-tailed hawks. Penicillin plus streptomycin caused no such depression of SI. Lymphocytes from all 3 species yielded maximum responses with a 48-hour prelabel and 12- to- 16 hour postlabel incubation period at 41 C and 1:20 blood dilution. Optimal mitogen concentrations for lymphocytes from bald eagles, red-tailed hawks, and great horned owls were 25 micrograms, 10 micrograms, and 10 micrograms of phytohemagglutinin-P/well, respectively, and 2.5 micrograms, 10 micrograms, and 10 micrograms of concanavalin A/well, respectively. Differences in SI were not seen between the 2 radioactive labels. The optimal concentration of the [3H]thymidine label ranged from 0.06 to 0.125 microCi/well. PMID:6524727

  7. Intermittent Theta Burst Over M1 May Increase Peak Power of a Wingate Anaerobic Test and Prevent the Reduction of Voluntary Activation Measured with Transcranial Magnetic Stimulation.

    PubMed

    Giboin, Louis-Solal; Thumm, Patrick; Bertschinger, Raphael; Gruber, Markus

    2016-01-01

    Despite the potential of repetitive transcranial magnetic stimulation (rTMS) to improve performances in patients suffering from motor neuronal afflictions, its effect on motor performance enhancement in healthy subjects during a specific sport task is still unknown. We hypothesized that after an intermittent theta burst (iTBS) treatment, performance during the Wingate Anaerobic Test (WAnT) will increase and supraspinal fatigue following the exercise will be lower in comparison to a control treatment. Ten subjects participated in two randomized experiments consisting of a WAnT 5 min after either an iTBS or a control treatment. We determined voluntary activation (VA) of the right knee extensors with TMS (VATMS) and with peripheral nerve stimulation (VAPNS) of the femoral nerve, before and after the WAnT. T-tests were applied to the WAnT results and a two way within subject ANOVA was applied to VA results. The iTBS treatment increased the peak power and the maximum pedalling cadence and suppressed the reduction of VATMS following the WAnT compared to the control treatment. No behavioral changes related to fatigue (mean power and fatigue index) were observed. These results indicate for the first time that iTBS could be used as a potential intervention to improve anaerobic performance in a sport specific task. PMID:27486391

  8. Intermittent Theta Burst Over M1 May Increase Peak Power of a Wingate Anaerobic Test and Prevent the Reduction of Voluntary Activation Measured with Transcranial Magnetic Stimulation

    PubMed Central

    Giboin, Louis-Solal; Thumm, Patrick; Bertschinger, Raphael; Gruber, Markus

    2016-01-01

    Despite the potential of repetitive transcranial magnetic stimulation (rTMS) to improve performances in patients suffering from motor neuronal afflictions, its effect on motor performance enhancement in healthy subjects during a specific sport task is still unknown. We hypothesized that after an intermittent theta burst (iTBS) treatment, performance during the Wingate Anaerobic Test (WAnT) will increase and supraspinal fatigue following the exercise will be lower in comparison to a control treatment. Ten subjects participated in two randomized experiments consisting of a WAnT 5 min after either an iTBS or a control treatment. We determined voluntary activation (VA) of the right knee extensors with TMS (VATMS) and with peripheral nerve stimulation (VAPNS) of the femoral nerve, before and after the WAnT. T-tests were applied to the WAnT results and a two way within subject ANOVA was applied to VA results. The iTBS treatment increased the peak power and the maximum pedalling cadence and suppressed the reduction of VATMS following the WAnT compared to the control treatment. No behavioral changes related to fatigue (mean power and fatigue index) were observed. These results indicate for the first time that iTBS could be used as a potential intervention to improve anaerobic performance in a sport specific task. PMID:27486391

  9. Increased anxiety induced by listening to unpleasant music during stress exposure is associated with reduced blood pressure and ACTH responses in healthy men.

    PubMed

    Jezova, Daniela; Hlavacova, Natasa; Makatsori, Aikaterini; Duncko, Roman; Loder, Ingrid; Hinghofer-Szalkay, Helmut

    2013-01-01

    The relationship between anxiety and the neuroendocrine response to stress stimuli is still not fully understood. The aim of this study was to evaluate the contribution of an acute increase in state anxiety to neuroendocrine activation under stress conditions. To do so, it was necessary to find a stress condition of the same character and intensity with and without a rise in state anxiety. We decided to examine the effects of listening to music on anxiety and to apply a new methodological approach. A group of 14 healthy volunteers participated in a counterbalanced crossover design study. The stress procedure consisted of mental (Stroop test, mental arithmetic) and physical (handgrip exercise) tasks combined with listening to music played forward (pleasant) or backwards (unpleasant). The results confirmed our hypothesis, namely the condition with listening to unpleasant music was anxiogenic, while the other was not. In case of increased state anxiety, the rise in ACTH concentrations in response to mental challenge and the increase in systolic blood pressure induced by handgrip exercise was reduced compared to the situation with unchanged anxiety. Concentrations of testosterone, oxytocin, vasopressin and aldosterone were slightly increased in response to the stress paradigm accompanied with increased anxiety. In conclusion, the present data demonstrate that an acute increase in state anxiety contributes to neuroendocrine activation under stress conditions. Moreover, the results show that listening to music may both positively and negatively influence the perception of stress and the level of anxiety, which might have functional consequences.

  10. Modification of urinary secretion of 8-hydroxy-2'-deoxyguanosine and serum ACTH concentration following repetitive parabolic flights.

    PubMed

    Nomura, J; Arase, Y; Sugaya, S; Moriya, T; Chen, Z; Takahashi, S; Kita, K; Kikuno, K; Nomura, F; Suzuki, N

    2001-07-01

    It is important to clarify the molecular mechanisms of physiological responses of the human body to changes in gravity. Previous reports demonstrated that gravity-changing stress increases the human urinary concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG). However, it has yet to be clarified whether repetitive parabolic flight modulates the urinary concentration of 8-OHdG after exposure to gravity-changing stress. In the present study, the effects of the number of previous experiences with parabolic flight on urinary excretion of 8-OHdG and concentration of serum ACTH were examined in 12 healthy volunteers.

  11. Metastatic islet cell tumor with ACTH, gastrin, and glucagon secretion. Clinical and pathologic studies with multiple therapies.

    PubMed

    Lokich, J; Bothe, A; O'Hara, C; Federman, M

    1987-06-15

    A patient with metastatic islet cell carcinoma demonstrated multiple clinical syndromes simultaneously with secretion of ACTH, gastrin, glucagon, and serotonin. Hepatic arterial embolization resulted in an initial decrease in all secretory products, which was sustained for glucagon and serotonin. Recrudescence of the Cushings and Zollinger-Ellison syndrome was managed by surgical extirpation of the primary tumor and regional metastases as well as bilateral adrenalectomy. Electron microscopy and immunocytochemistry of the primary tumor and the metastatic lesions revealed the presence of multiple types of granules within single cells and, different patterns of secretory profiles in different tumor sites.

  12. The relationship between luteinizing hormone and estradiol secretion in female precocious puberty: evaluation by sensitive gonadotropin assays and the leuprolide stimulation test.

    PubMed

    Garibaldi, L R; Aceto, T; Weber, C; Pang, S

    1993-04-01

    We used the GnRH agonist (GnRHa) stimulation test (20 micrograms/kg leuprolide sc, followed by 24-h serial sampling) to investigate the relationship between gonadotropin and estradiol (E2) secretion in the early phase of female central precocious puberty (CPP). Girls with CPP and moderately increased (early pubertal) peak E2 concentrations after GnRHa stimulation (136 +/- 11 pmol/L; range, 92-176; group B; n = 7) were compared to girls with CPP and higher (midpubertal) peak E2 responses to GnRHa (mean +/- SE, 590 +/- 63 pmol/L; range, 235-1189; group C; n = 19) and to a group of subjects with no breast development and a prepubertal hypothalamic-pituitary-gonadal axis (peak E2 response to GnRHa, 39 +/- 7 pM/L; range, 18-62; group A; n = 6). Compared to group A subjects, patients in group B had similar (P > 0.2) peak GnRHa-stimulated LH concentrations (B, 4.8 +/- 1 IU/L; A, 2.3 +/- 0.5 IU/L) and peak nocturnal LH (B, 0.81 +/- 0.2; A, 0.25 +/- 0 IU/L), but higher peak GnRHa-stimulated FSH concentrations (B, 26 +/- 7; A, 11 +/- 2 IU/L; P < 0.05) and mean nocturnal FSH (B, 4.2 +/- 1; A, 1.1 +/- 0.3 IU/L; P < 0.05) concentrations. Compared to group B, group C patients had higher (P < 0.001) GnRHa-stimulated peak LH (67 +/- 19 IU/L) and higher (P < 0.05) peak nocturnal LH (9.7 +/- 2.9 IU/L) concentrations, but similar GnRHa-stimulated peak FSH (27 +/- 3 IU/L) and mean nocturnal FSH (3.8 +/- 0.5 IU/L) levels. Group C patients with a ratio of peak GnRHa-stimulated LH to FSH concentrations below or above 1, respectively, had similar peak E2 responses to GnRHa (516 +/- 80 vs. 644 +/- 92 pM/L; P > 0.1). Stepwise regression analysis indicated that the peak LH response to GnRHa (r = 0.76; P < 0.001), but none of the FSH secretory parameters (P > 0.10), affected the E2 response to GnRHa. These data suggest that girls with CPP in the early phase of activation of the hypothalamic-pituitary-gonadal axis are capable of clinically relevant E2 production, which may occur in the face of

  13. Efficacy of sildenafil for Japanese patients with audio-visual sexual stimulation (AVSS) test by the RigiScan Plus.

    PubMed

    Soh, J; Naya, Y; Ushijima, S; Naitoh, Y; Ochiai, A; Mizutani, Y; Kawauchi, A; Miki, T; Fujiwara, T

    2006-01-01

    Sildenafil is most effective in men with mild-to-moderate ED, but not severe ED in Japan. In order to evaluate the efficacy of sildenafil, we conducted the present study using the AVSS test by the RigiScan Plus. The subjects were 56 patients (age: 34-82 years, mean: 60.5 years) with ED. The IIEF5 questionnaire and the AVSS test were conducted before and after administration of sildenafil. The penile rigidity could not be measured in 19 patients. Of these 19, sildenafil was effective in 7 and not effective in 12. The 7 cases in whom sildenafil was effective were all false-negatives. The sensitivity of sildenafil was 84%, and its specificity was 100%. This study suggests that the AVSS test by RigiScan Plus can objectively evaluate the efficacy of sildenafil, and shows potential for predicting that efficacy.

  14. The use of the Bilingual Aphasia Test for assessment and transcranial direct current stimulation to modulate language acquisition in minimally verbal children with autism.

    PubMed

    Schneider, Harry D; Hopp, Jenna P

    2011-06-01

    Minimally verbal children with autism commonly demonstrate language dysfunction, including immature syntax acquisition. We hypothesised that transcranial direct current stimulation (tDCS) should facilitate language acquisition in a cohort (n = 10) of children with immature syntax. We modified the English version of the Bilingual Aphasia Test (BAT) to test only basic canonical subject-verb-object sentences. We tested syntactic accuracy after teaching then testing all vocabulary from the subsequent syntax test to ensure validity of syntactic scoring. We used scaffolding sentences for syntax training. All procedures were performed both before and after tDCS. Results demonstrated a large effect size of the difference between pre-/post-tDCS groups (p < 0.0005, d = 2.78), indicating syntax acquisition. Combining a modified BAT with tDCS constitutes effective modalities for assessment and treatment of immature syntax in children with autism. Future studies should explore the BAT for patients with an inability to use or understand language, in particular bilingual children with autism.

  15. Human chorionic gonadotropin (hCG) fails to stimulate gonocyte differentiation in newborn mouse testes in organ culture.

    PubMed

    Zhou, B; Hutson, J M

    1995-02-01

    The primitive germ cells within the postnatal testis differentiate through several steps to form primary spermatocytes, which are required for postpubertal spermatogenesis. It is postulated that this germ cell development is controlled by the hypothalamic-pituitary-gonadal axis. To study the effect of human chorionic gonadotropin (hCG) on postnatal testicular germ cell differentiation, especially on gonocytes, newborn mouse testes (n = 75) were cultured for 7 days in vitro. The synthetic serum-free medium contained either hCG or exogenous human recombinant müllerian inhibiting substance (MIS) plus transferrin, insulin and retinoic acid (TIRA). Fetal calf serum 10% (FCS) was used for control medium. Thirty-eight newborn mouse testes were cultured with hCG (0.1 to 2.0 IU/ml). The percentages of differentiated type-A spermatogonia were not significantly increased compared with synthetic medium alone (NS, p > 0.05), but were only 5 to 7% (p < 0.001) of that of serum-containing medium. By contrast, normal transformation from gonocytes to type-A spermatogonia occurred in newborn mouse testes (n = 10) cultured with serum-free medium containing exogenous MIS. The percentage of differentiated type-A spermatogonia was approximately 77% (NS, p > 0.05) of those seen in serum-containing medium. These findings demonstrate that the transformation of gonocytes to type-A spermatogonia is regulated by MIS, rather than hCG. As early germ cell transformation is deficient in boys with cryptorchidism, the role of hCG in the treatment of infertility associated with undescended testes should be reevaluated.

  16. Neonatal ACTH administration elicits long-term changes in forebrain monoamine innervation. Subsequent disruptions in hypothalamic-pituitary-adrenal and gonadal function.

    PubMed

    Alves, S E; Akbari, H M; Anderson, G M; Azmitia, E C; McEwen, B C; Strand, F L

    1997-04-24

    The findings from this study demonstrated that the manipulation of the HPA system resulting from ACTH administration during neonatal development produces long-term, differential effects, not only on adrenocortical activity, but also on the activity and integrity of the forebrain monoamine systems. Increased concentrations of the monoamines within the forebrain regions studied at days 7 and 15, suggest a hastened maturation of these neural systems in animals neonatally treated with ACTH. The observed neurochemical alterations in these animals at one year are suggestive of an accelerated aging in the monoamine systems. A further consequence of these disturbances during development is an altered functioning of the HPG axis, as demonstrated by a delayed onset of puberty as previously reported, as well as significantly decreased proestrus plasma estradiol. Although deficits in sexual behavior also existed, it seems probable that these behavioral changes are a manifestation of altered neural systems regulating the ability to cope with a novel stimulus or situation, rather than a disruption of the "feminization" of the brain during sexual differentiation. This is in contrast to the male rat which exhibits permanent deficits in male typical sexual behavior following developmental ACTH treatment. The clinical relevance of these findings may be extensive. Perinatal exposure to events or agents that markedly increase ACTH and the corticosteroids may cause significant immediate and long-term changes in central monoamine functioning. These changes may constitute some of the most deleterious effects of stress exposure in infants and children. The alterations may be especially devastating in individuals with predispositions to stress-sensitive disorders such as anxiety, depression, and Tourette's syndrome. Finally, the use of ACTH in the treatment of infantile spasms may need to be reassessed in light of the possible long-term effects of ACTH on central monoamine functioning.

  17. Imitation, social facilitation, and the effects of ACTH 4-10 on rats' bar-pressing behavior.

    PubMed

    Henning, J M; Zentall, T R

    1981-03-01

    The effects of ACTH 4-10 on rats' imitation learning was examined during the acquisition and extinction of a bar-press response for water reinforcement. Rats were exposed to either a bar-pressing conspecific (OB), an experimentally naive conspecific (ON), or an empty box (OE) during bar-press acquisition. In a factorial design, each rat was then exposed to one of the same three conditions during extinction. An 80 mcg dose of ACTH 4-10 was administered to half of the rats in each group prior to observation. Performance differences during acquisition were generally small, but significant performance differences during extinction were found. Social facilitation was indicated by the finding that rats extinguished in the presence of a conspecific exhibited significantly greater resistance to extinction than rats extinguished in the presence of an empty box. An imitation effect was also found. Rats that observed a bar-pressing conspecific during both acquisition and extinction (group OB-OB) showed significantly greater resistance top extinction than did groups OB-ON, CB-OE, or OE-OE. There were no significant effects of the hormone, however, relative to saline controls. PMID:6263117

  18. Phenotype-Genotype Association Analysis of ACTH-Secreting Pituitary Adenoma and Its Molecular Link to Patient Osteoporosis

    PubMed Central

    Wang, Renzhi; Yang, Yakun; Sheng, Miaomiao; Bu, Dechao; Huang, Fengming; Liu, Xiaohai; Zhou, Cuiqi; Dai, Congxin; Sun, Bowen; Zhu, Jindong; Qiao, Yi; Yao, Yong; Zhu, Huijuan; Lu, Lin; Pan, Hui; Feng, Ming; Deng, Kan; Xing, Bing; Lian, Wei; Zhao, Yi; Jiang, Chengyu

    2016-01-01

    Adrenocorticotrophin (ACTH)-secreting pituitary adenoma, also known as Cushing disease (CD), is rare and causes metabolic syndrome, cardiovascular disease and osteoporosis due to hypercortisolism. However, the molecular pathogenesis of CD is still unclear because of a lack of human cell lines and animal models. Here, we study 106 clinical characteristics and gene expression changes from 118 patients, the largest cohort of CD in a single-center. RNA deep sequencing is used to examine genotypic changes in nine paired female ACTH-secreting pituitary adenomas and adjacent nontumorous pituitary tissues (ANPT). We develop a novel analysis linking disease clinical characteristics and whole transcriptomic changes, using Pearson Correlation Coefficient to discover a molecular network mechanism. We report that osteoporosis is distinguished from the phenotype and genotype analysis. A cluster of genes involved in osteoporosis is identified using Pearson correlation coefficient analysis. Most of the genes are reported in the bone related literature, confirming the feasibility of phenotype-genotype association analysis, which could be used in the analysis of almost all diseases. Secreted phosphoprotein 1 (SPP1), collagen type I α 1 chain (COL1A1), 5′-nucleotidase ecto (NT5E), HtrA serine peptidase 1 (HTRA1) and angiopoietin 1 (ANGPT1) and their signalling pathways are shown to be involved in osteoporosis in CD patients. Our discoveries provide a molecular link for osteoporosis in CD patients, and may open new potential avenues for osteoporosis intervention and treatment. PMID:27690016

  19. Hypothermic and antipyretic effects of ACTH (1-24) and alpha-melanotropin in guinea-pigs

    NASA Technical Reports Server (NTRS)

    Kandasamy, S. B.; Williams, B. A.

    1984-01-01

    Intracerebroventricular administration of adrenocorticotropin (ACTH 1-24) and alpha-melanotropin (alpha-MSH), peptides which occur naturally in brain induced dose-related hypothermia in guinea-pigs at room temperature (21 C) and also produced greater hypothermia at low (10 C) ambient temperature. However, when the experiments were repeated in a warm (30 C) environment, no effect on body temperature was observed. These results indicate that the peptides did not reduce the central set-point of temperature control. The hypothermia induced by ACTH and alpha-MSH was not mediated via histamine H1- or H2-receptors and serotonin since the H1-receptor antagonist, mepyramine, the H2-receptor antagonist, cimetidine, and the serotonin antagonist, methysergide, had no antagonistic effects. The peptides were antipyretic since they reduced pyrogen-induced-fever and hyperthermia due to prostaglandin E2, norepinephrine and dibutyryl cAMP, at a dose which did not affect normal body temperature. The powerful central effects of these peptides on normal body temperature, fever and hyperthermia, together with their presence of the brain regions important to temperature control, suggest that they participate in thermoregulation.

  20. Microbial Stimulation and Succession following a Test Well Injection Simulating CO₂ Leakage into a Shallow Newark Basin Aquifer

    PubMed Central

    O’Mullan, Gregory; Dueker, M. Elias; Clauson, Kale; Yang, Qiang; Umemoto, Kelsey; Zakharova, Natalia; Matter, Juerg; Stute, Martin; Takahashi, Taro; Goldberg, David

    2015-01-01

    In addition to efforts aimed at reducing anthropogenic production of greenhouse gases, geological storage of CO2 is being explored as a strategy to reduce atmospheric greenhouse gas emission and mitigate climate change. Previous studies of the deep subsurface in North America have not fully considered the potential negative effects of CO2 leakage into shallow drinking water aquifers, especially from a microbiological perspective. A test well in the Newark Rift Basin was utilized in two field experiments to investigate patterns of microbial succession following injection of CO2-saturated water into an isolated aquifer interval, simulating a CO2 leakage scenario. A decrease in pH following injection of CO2 saturated aquifer water was accompanied by mobilization of trace elements (e.g. Fe and Mn), and increased bacterial cell concentrations in the recovered water. 16S ribosomal RNA gene sequence libraries from samples collected before and after the test well injection were compared to link variability in geochemistry to changes in aquifer microbiology. Significant changes in microbial composition, compared to background conditions, were found following the test well injections, including a decrease in Proteobacteria, and an increased presence of Firmicutes, Verrucomicrobia and microbial taxa often noted to be associated with iron and sulfate reduction. The concurrence of increased microbial cell concentrations and rapid microbial community succession indicate significant changes in aquifer microbial communities immediately following the experimental CO2 leakage event. Samples collected one year post-injection were similar in cell number to the original background condition and community composition, although not identical, began to revert toward the pre-injection condition, indicating microbial resilience following a leakage disturbance. This study provides a first glimpse into the in situ successional response of microbial communities to CO2 leakage after subsurface

  1. MODELING OF FLOW AND TRANSPORT INDUCED BY PRODUCTION OF HYDROFRACTURE-STIMULATED GAS WELLS NEAR THE RULISON NUCLEAR TEST

    SciTech Connect

    Hodges, Rex A.; Cooper, Clay; Falta, Ronald

    2012-09-17

    The Piceance Basin in western Colorado contains significant reserves of natural gas in poorly connected, low-permeability (tight) sandstone lenses of the Mesaverde Group. The ability to enhance the production of natural gas in this area has long been a goal of the oil and gas industry. The U.S. Atomic Energy Commission, a predecessor agency to the U.S. Department of Energy (DOE) and the U.S. Nuclear Regulatory Commission, participated in three tests using nuclear detonations to fracture tight formations in an effort to enhance gas production. The tests were conducted under Project Plowshare, a program designed to identify peaceful, beneficial uses for nuclear devices. The first, Project Gasbuggy, was conducted in 1967 in the San Juan Basin of New Mexico. The two subsequent tests, Project Rulison in 1969 and Project Rio Blanco in 1973, were in the Piceance Basin. The ability to enhance natural gas production from tight sands has become practical through advances in hydraulic fracturing technology (hydrofracturing). This technology has led to an increase in drilling activity near the Rulison site, raising concerns that contamination currently contained in the subsurface could be released through a gas well drilled too close to the site. As wells are drilled nearer the site, the DOE Office of Legacy Management has taken the approach outlined in the June 2010 Rulison Path Forward document (DOE 2010), which recommends a conservative, staged approach to gas development. Drillers are encouraged to drill wells in areas with a low likelihood of encountering contamination (both distance and direction from the detonation zone are factors) and to collect data from these wells prior to drilling nearer the site’s 40 acre institutional control boundary (Lot 11). Previous modeling results indicate that contamination has been contained within Lot 11 (Figure 1). The Path Forward document couples the model predictions with the monitoring of gas and produced water from the gas wells

  2. Detection of Delta9-tetrahydrocannabinol and amphetamine-type stimulants in oral fluid using the Rapid Stat point-of-collection drug-testing device.

    PubMed

    Röhrich, J; Zörntlein, S; Becker, J; Urban, R

    2010-04-01

    The Rapid Stat assay, a point-of-collection drug-testing device for detection of amphetamines, cannabinoids, cocaine, opiates, methadone, and benzodiazepines in oral fluid, was evaluated for cannabis and amphetamine-type stimulants. The Rapid Stat tests (n = 134) were applied by police officers in routine traffic checks. Oral fluid and blood samples were analyzed using gas chromatography-mass spectrometry (GC-MS) for Delta(9)-tetrahydrocannabinol, amphetamine, methamphetamine, methylenedioxymethamphetamine, methylenedioxyethylamphetamine, and methylenedioxyamphetamine. The comparison of GC-MS analysis of oral fluid with the Rapid Stat results for cannabis showed a sensitivity of 85%, a specificity of 87%, and a total confirmation rate of 87%. When compared with serum, the sensitivity of the cannabis assay decreased to 71%, the specificity to 60%, and the total confirmation rate to 66%. These findings were possibly caused by an incorrect reading of the THC test results. Comparison of the Rapid Stat amphetamine assay with GC-MS in oral fluid showed a sensitivity of 94%, a specificity of 97%, and a total confirmation rate of 97%. Compared with serum, a sensitivity of 100%, a specificity of 90%, and a total confirmation rate of 92% was found. The amphetamine assay must, therefore, be regarded as satisfactory.

  3. Field test of a cross-injection scheme for stimulating in situ denitrification near a municipal water supply well

    NASA Astrophysics Data System (ADS)

    Gierczak, R.; Devlin, J. F.; Rudolph, D. L.

    2007-01-01

    A pilot-scale test of an in situ denitrification scheme was undertaken to assess an adaptation of the nutrient injection wall (NIW) technology for treating a deep (30-40 m) nitrate contamination problem (N-NO 3- ˜ 10-12 mg/L). The adaptation is called the Cross-Injection Scheme (CIS). It duplicates the NIW method without a wall; wells are installed and operated directly in the aquifer and high-flux zones of the aquifer are preferentially targeted for treatment. The test was conducted on the site of a municipal water supply well field, with the supply well pumping between 15-80 m 3/h. Acetate was periodically injected into the aquifer between an injection-extraction well pair positioned across the normal direction of flow. The injected pulses were then permitted to move with the water toward the municipal wells, providing a carbon supply to drive the desired denitrification. The fate of nitrate, nitrite, acetate and sulphate were monitored at multilevel wells located between the injection location and the municipal wells. The acetate pulsing interval was approximately weekly (9 h injections), so that the system was operating passively 95% of the time. Previous work on the site has established that the highest solute fluxes were associated with a 1-3 m thick zone about 35 m below surface. This zone was found to respond to the acetate additions as a function of the municipal pumping rate and the carbon-to-nitrogen ratio (i.e., determined by the injected acetate concentration). Initially, acetate was injected just below the theoretical stoichiometric requirement for complete denitrification and nitrate disappearance was accompanied by nitrite production. Increasing the C:N ratio (doubling the acetate injection concentration) increased the removal of nitrate and diminished the occurrence of nitrite. Slowing the municipal pumping rate, with a C:N ratio of 1.2-1.6, resulted in complete nitrate attenuation with no nitrite production and no sulfate reduction. The

  4. Stimulation of interferons and endorphins/enkephalins by electro-aerosol inhalation? An experimental approach for testing an expanded hypothesis

    NASA Astrophysics Data System (ADS)

    Wehner, A. P.

    1984-03-01

    The biological effects of endorphins/enkephalins and of interferons closely resemble those attributed to air ions and electro-aerosols. Air ions/electro-aerosols have been reported to affect brain functions and feelings of “well-being”; to have sedative and analgesic effects; to be therapeutically effective in certain viral (e.g., upper respiratory) infections; and to have tumor-attenuating effects. It is, therefore, conceivable that endorphins/enkephalins and interferons might be the mediators of these air ion/electro-aerosol effects. An experimental approach for testing this hypothesis is described. It calls for mice to be challenged with a suitable agent and to be exposed under appropriate conditions to a negatively charged aerosol of physiological saline 6 hours/day for up to 3 weeks; for the serial sacrifice of subgroups of these mice; for collecting blood and brains of the sacrificed animals; for the bioassay of the sera for interferon; and for radioimmunoassays of brains for endorphins/enkephalins. Special considerations, necessitated by the nature of the experiment, are discussed.

  5. Assessment of immune response in periparturient dairy cows using ex vivo whole blood stimulation assay with lipopolysaccharides and carrageenan skin test.

    PubMed

    Jahan, N; Minuti, A; Trevisi, E

    2015-06-15

    The transition period is known to be the most critical phase in the life of high yielding dairy cow. Changes in the immune functions have been observed during the transition period which may account for the onset of clinical and subclinical (e.g. inflammatory response) problems at calving or at the beginning of lactation however this relationship has not yet been adequately investigated. Thus, to establish the potential of the periparturient dairy cow's immune system to respond to stimuli, two challenges [an ex vivo whole blood stimulation assay (WBA) with lipopolysaccharides and a carrageenan skin test (CST)] were performed in addition to characterizing the metabolic and inflammatory profile. The WBA was performed using 0, 0.01 and 5 μg LPS/mL on whole blood and CST was administered by subcutaneous injection of 0.7 mL solution containing 4.2mg of carrageenan to the shoulder region of the cows. These tests were performed on 10 Holstein-Friesian cows at -45 ± 2, -20 ± 2, -3, 3, 7, 28 ± 2 days from parturition (DFP). Cows were also monitored for health status, body condition score, milk yield. The results demonstrate a higher production of IL-1β and IL-6 from leukocytes after LPS stimulation around calving (from -3 to 3 DFP) compared to -45 DFP (P < 0.05). Moreover, IL-6 (but not IL-1β) was able to reach close to the maximum response at the lower stimulus intensity (0.01 μg LPS/mL), maintaining a higher response over a longer time in early lactation. The release of higher levels of IL-6 in the transition period, with low LPS dose, suggests its crucial role in the regulation of inflammatory response around calving. The response of cows to CST decreased a few days before calving (-3 DFP) compared with response at -45 and 28 DFP (P<0.05), and remained low in the first week of lactation. This result suggests the reduction of the functionality of some vascular factors, which decreases diapedesis. Overall, the WBA and CST tests confirm changes in immunocompetence

  6. Requirement of AMPA receptor stimulation for the sustained antidepressant activity of ketamine and LY341495 during the forced swim test in rats.

    PubMed

    Koike, Hiroyuki; Chaki, Shigeyuki

    2014-09-01

    Ketamine, a non-competitive N-methyl-d-aspartate receptor antagonist, and group II metabotropic glutamate (mGlu2/3) receptor antagonists produce antidepressant effects in animal models of depression, which last for at least 24h, through the transient increase in glutamate release, leading to activation of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA) receptor. Both ketamine and an mGlu2/3 receptor antagonist reportedly increase the expression of GluR1, an AMPA receptor subunit, within 24h, which may account for the sustained enhancement of excitatory synaptic transmission following ketamine administration. However, whether the sustained increase in AMPA receptor-mediated synaptic transmission is associated with the antidepressant effects of ketamine and mGlu2/3 receptor antagonists has not yet been investigated. In the present study, to address this question, we tested whether AMPA receptor stimulation at 24h after a single injection of ketamine or an mGlu2/3 receptor antagonist, (2S)-2-amino-2-[(1S,2S)-2-carboxycycloprop-1-yl]-3-(xanth-9-yl)propanoic acid (LY341495) was necessary for the antidepressant effect of these compounds using a forced swim test in rats. A single injection of ketamine or LY341495 at 24h before the test significantly decreased the immobility time. An AMPA receptor antagonist, 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide (NBQX), administered 30min prior to the test significantly and dose-dependently reversed the antidepressant effects of ketamine and LY341495, while NBQX itself had no effect on the immobility time. Our findings suggest that AMPA receptor stimulation at 24h after a single injection of ketamine or LY341495 is required to produce the anti-immobility effects of these compounds. Moreover, the present results provide additional evidence that an mGlu2/3 receptor antagonist may share some of neural mechanisms with ketamine to exert antidepressant effects.

  7. Controlled progressive innate immune stimulation regimen prevents the induction of sickness behavior in the open field test.

    PubMed

    Chen, Qun; Tarr, Andrew J; Liu, Xiaoyu; Wang, Yufen; Reed, Nathaniel S; Demarsh, Cameron P; Sheridan, John F; Quan, Ning

    2013-01-01

    Peripheral immune activation by bacterial mimics or live replicating pathogens is well known to induce central nervous system activation. Sickness behavior alterations are often associated with inflammation-induced increases in peripheral proinflammatory cytokines (eg, interleukin [IL]-1β and IL-6). However, most researchers have used acute high dose endotoxin/bacterial challenges to observe these outcomes. Using this methodology may pose inherent risks in the translational interpretation of the experimental data in these studies. Studies using Escherichia coli have yet to establish the full kinetics of repeated E. coli peripheral injections. Therefore, we sought to examine the effects of repeated low dose E. coli on sickness behavior and local peripheral inflammation in the open field test. Results from the current experiments showed a behavioral dose response, where increased amounts of E. coli resulted in correspondingly increased sickness behavior. Furthermore, animals that received a subthreshold dose (ie, one that did not cause sickness behavior) of E. coli 24 hours prior were able to withstand a larger dose of E. coli on the second day (a dose that would normally cause sickness behavior in mice without prior exposure) without inducing sickness behavior. In addition, animals that received escalating subthreshold doses of E. coli on days 1 and 2 behaviorally tolerated a dose of E. coli 25 times higher than what would normally cause sickness behavior if given acutely. Lastly, increased levels of E. coli caused increased IL-6 and IL-1β protein expression in the peritoneal cavity, and this increase was blocked by administering a subthreshold dose of E. coli 24 hours prior. These data show that progressive challenges with subthreshold levels of E. coli may obviate the induction of sickness behavior and proinflammatory cytokine expression.

  8. Effects of 14-methoxymetopon, a potent opioid agonist, on the responses to the tail electric stimulation test and plus-maze activity in male rats: neuroendocrine correlates.

    PubMed

    Urigüen, Leyre; Fernández, Beatriz; Romero, Eva Maria; De Pedro, Nuria; Delgado, Maria Jesús; Guaza, Carmen; Schmidhammer, Helmut; Viveros, Maria Paz

    2002-03-15

    We have studied the effects of 14-methoxymetopon (HS 198), a potent opioid agonist, on the responses to the tail electric stimulation test and plus-maze activity of adult male rats. The prototype mu agonist morphine was used as the drug of reference. Besides we addressed the effects of HS 198 on the serum corticosterone levels and on serotonergic systems of discrete brain regions. Both drugs were administered subcutaneously. Morphine (5 mg/kg) and HS 198 (30 microg/kg) induced a similar effect on the nociceptive test, with both drugs significantly increasing the threshold for the vocalization afterdischarge, which is related to the emotional component of pain. In the plus-maze, morphine (5 mg/kg) and HS 198 (20 and 30 microg/kg) induced similar increases in the percentages of entries and time in the open arms, two parameters related to the anxiety state of the animals. The results indicate that HS 198 is far more potent than morphine in reducing the emotive/affective component of pain and in inducing an anxiolytic effect. HS 198 (30 microg/kg) also induced parallel increases in the serum corticosterone levels and the hypothalamic serotonin content. A possible correlation between the anxiolytic action of the drug and its effect on the hypothalamic serotonergic system is suggested.

  9. ATRAZINE DOES NOT INDUCE GASTROINTESTINAL DISCOMFORT (PICA) IN RATS AT DOSES THAT INCREASE ACTH ANDCORTICOSTERONE RELEASE AND CAUSE CONDITIONED TASTE AVERSION.

    EPA Science Inventory

    Previous work has shown that a single oral administration of atrazine (ATR), a chlorotriazine herbicide, induces dose-dependent increases in plasma adrenocorticotropic hormone (ACTH) and serum corticosterone (CORT), with a LOEL of 12.5mg/kg. The mechanism for these effects is unk...

  10. Lycopene and Beta-Carotene Induce Growth Inhibition and Proapoptotic Effects on ACTH-Secreting Pituitary Adenoma Cells

    PubMed Central

    Leite de Oliveira, Felipe; Soares, Nathália; de Mattos, Rômulo Medina; Hecht, Fábio; Dezonne, Rômulo Sperduto; Vairo, Leandro; Goldenberg, Regina Coeli dos Santos; Gomes, Flávia Carvalho Alcântara; de Carvalho, Denise Pires; Gadelha, Mônica R.; Nasciutti, Luiz Eurico; Miranda-Alves, Leandro

    2013-01-01

    Pituitary adenomas comprise approximately 10–15% of intracranial tumors and result in morbidity associated with altered hormonal patterns, therapy and compression of adjacent sella turcica structures. The use of functional foods containing carotenoids contributes to reduce the risk of chronic diseases such as cancer and vascular disorders. In this study, we evaluated the influence of different concentrations of beta-carotene and lycopene on cell viability, colony formation, cell cycle, apoptosis, hormone secretion, intercellular communication and expression of connexin 43, Skp2 and p27kip1 in ACTH-secreting pituitary adenoma cells, the AtT20 cells, incubated for 48 and 96 h with these carotenoids. We observed a decrease in cell viability caused by the lycopene and beta-carotene treatments; in these conditions, the clonogenic ability of the cells was also significantly decreased. Cell cycle analysis revealed that beta-carotene induced an increase of the cells in S and G2/M phases; furthermore, lycopene increased the proportion of these cells in G0/G1 while decreasing the S and G2/M phases. Also, carotenoids induced apoptosis after 96 h. Lycopene and beta-carotene decreased the secretion of ACTH in AtT20 cells in a dose-dependent manner. Carotenoids blocked the gap junction intercellular communication. In addition, the treatments increased the expression of phosphorylated connexin43. Finally, we also demonstrate decreased expression of S-phase kinase-associated protein 2 (Skp2) and increased expression of p27kip1 in carotenoid-treated cells. These results show that lycopene and beta-carotene were able to negatively modulate events related to the malignant phenotype of AtT-20 cells, through a mechanism that could involve changes in the expression of connexin 43, Skp2 and p27kip1; and suggest that these compounds might provide a novel pharmacological approach to the treatment of Cushing’s disease. PMID:23667519

  11. The Value of Somatostatin Receptor Imaging with In-111 Octreotide and/or Ga-68 DOTATATE in Localizing Ectopic ACTH Producing Tumors

    PubMed Central

    Gözde Özkan, Zeynep; Kuyumcu, Serkan; Balköse, Deniz; Özkan, Berker; Aksakal, Nihat; Yılmaz, Ebru; Şanlı, Yasemin; Türkmen, Cüneyt; Aral, Ferihan; Adalet, Işık

    2013-01-01

    Objective: We aimed to evaluate the value of somatostatin receptor imaging (SRI) with In-111 octreotide and Ga-68 DOTATATE in localizing ectopic ACTH producing tumors. Methods: Nineteen patients who had In-111 octreotide somatostatin receptor scintigraphy (SRS) and/or Ga-68 DOTATATE PET-CT to localize ectopic ACTH producing tumors between the years 2000 and 2012 were included retrospectively in our study. The results of SRI were compared with clinical onset, radiological findings and surgical data of the patients. Results: Sixteen In-111 octreotide SRS and five Ga-68 DOTATATE PET-CT were performed in 19 patients. In eight out of 19 patients, ectopic ACTH secretion site could be detected. In five patients, SRS showed pathologic uptake. In four of these patients, surgery revealed pulmonary carcinoid tumors and in one patient pancreatic neuroendocrine tumor. In one patient, Ga-68 DOTATATE PET-CT revealed pathologic uptake in lung nodule which came out to be pulmonary carcinoid tumor. In another patient who had resection of metastases of atypical carcinoid tumor prior to scans, new metastatic foci were detected both with SRS and Ga-68 DOTATATE PET-CT imaging. In one patient, although SRS was negative, CT which was performed three years later showed a lung nodule diagnosed as pulmonary carcinoid tumor. In 11 patients, ectopic ACTH secretion site could not be detected. In 10 of those patients, scintigraphic and radiological imaging did not show any lesions and in one patient, Ga-68 DOTATATE PET-CT was false positive. Conclusion: SRI has a complementary role with radiological imaging in localizing ectopic ACTH secretion sites. PET-CT imaging with Ga-68 peptide conjugates is a promising new modality for this indication. Conflict of interest:None declared. PMID:24003397

  12. Adrenal Function Testing Following Hormone Therapy for Infantile Spasms: Case Series and Review of Literature

    PubMed Central

    Mytinger, John R.; Bowden, Sasigarn A.

    2015-01-01

    Prednisolone and adrenocorticotropic hormone (ACTH) are “hormone” therapies for infantile spasms. There is limited data on the occurrence of decreased adrenal reserve or signs of clinical adrenal insufficiency after hormone therapy. This is a retrospective medical record review of patients referred to our Infantile Spasms Program. Our standardized infantile spasms management guideline began in September 2012 and initially included a post-hormone laboratory assessment of adrenal function. Medical records were assessed for hormone treatments, adrenal function testing, and signs of adrenal insufficiency. Forty-two patients who received one or both hormone therapies met inclusion criteria. A post-hormone laboratory assessment of adrenal function was done in 14 patients. Of these 14 patients, 2 had an abnormal laboratory assessment of adrenal function, both by adrenal stimulation testing – one after ACTH and one after prednisolone. One patient received hydrocortisone replacement and the other received stress dose hydrocortisone as needed; neither patient developed signs of adrenal insufficiency. Another patient treated with both types of hormone therapy in tandem, who did not have a post-hormone laboratory assessment, developed signs of mild adrenal insufficiency and required replacement hydrocortisone. Our study suggests that adrenal suppression can occur after modern hormone therapy regimens. We found two patients with abnormal adrenal function testing after hormone therapy and another patient with signs adrenal insufficiency. Given the seriousness of adrenal crisis, caregiver education on the signs of adrenal insufficiency is critical. Greater vigilance may be indicated in patients receiving both types of hormone therapy in tandem. Although a routine post-hormone laboratory assessment of adrenal function may not be feasible in all patients, replacement or stress dose hydrocortisone is necessary for all patients with suspected adrenal insufficiency. PMID

  13. Transport mechanism of a new behaviorally highly potent adrenocorticotropic hormone (ACTH) analog, ebiratide, through the blood-brain barrier.

    PubMed

    Shimura, T; Tabata, S; Ohnishi, T; Terasaki, T; Tsuji, A

    1991-08-01

    The binding and internalization of a novel adrenocorticotropic hormone (ACTH) analog having a potent neuromodulating effect, ebiratide (H-Met(O2)-Glu-His-Phe-D-Lys-Phe-NH(CH2)8NH2), by isolated bovine brain capillaries, were examined. Metabolism of [5-125I-His]ebiratide occurred during a 30-min incubation with bovine brain capillaries at 37 degrees C. In the presence of 20 mM EDTA, added to inhibit this metabolism, the medium, after 30 min of incubation, contained 82.3 +/- 0.5% of the unchanged ebiratide. The total binding and acid-resistant binding of [125I]ebiratide increased with time and reached an equilibrium at about 15 min. The total binding and acid-resistant binding at 30 min (as the cell/medium ratios corrected with [14C]sucrose) were 13.07 +/- 0.86 and 5.00 +/- 0.18 microliters/mg of protein, respectively. The acid-resistant binding showed significant dependence on temperature and medium osmolarity. The [125I]ebiratide binding was significantly inhibited by dansylcadaverine, an endocytosis inhibitor. The saturable acid-resistant binding was obtained by the addition of unlabeled ebiratide (100 nM-5 mM), and the maximal internalization capacity (Bmax) at 30 min was 144.2 pmol/mg of protein, with the half-saturation constant (KD) of 62.1 microM. The nonsaturable acid-resistant binding [cell/medium ratio in the presence of the unlabeled compound (1 mM or more)] was 2.2 microliters/mg of protein. The acid-resistant binding was significantly inhibited by human ACTH, poly-L-lysine, protamine and E-2078, a basic peptide, but was not inhibited by poly-L-glutamate, insulin or transferrin. These results demonstrate that ebiratide is transported through the blood-brain barrier via a basic peptide-specific absorptive-mediated endocytosis.

  14. Effects of benzyl glucoside and chlorogenic acid from Prunus mume on adrenocorticotropic hormone (ACTH) and catecholamine levels in plasma of experimental menopausal model rats.

    PubMed

    Ina, Hiroji; Yamada, Kenji; Matsumoto, Kosai; Miyazaki, Toshio

    2004-01-01

    To investigate the effectiveness of benzyl beta-D-glucopyranoside (BG) and chlorogenic acid (CA), the constituents of the fruit of Prunus mume, for relieving tension in experimental menopausal model rats (M-rats) caused by ether stress, the effects of BG and CA on adrenocorticotropic hormone (ACTH) and catecholamine (adrenaline, noradrenaline, and dopamine) levels were examined in the plasma of M-rats. Caffeic acid, quinic acid, and rosmarinic acid, which are compounds structurally related to CA, were also examined. BG obviously recovered catecholamine levels decreased by ether stress and increased dopamine to high levels. On the other hand, CA significantly decreased the ACTH level increased by ether stress and showed the greatest effect of all compounds. These results suggest that BG and CA may contribute to relieving the tension in M-rats caused by ether stress.

  15. Ethanol induction of steroidogenesis in rat adrenal and brain is dependent upon pituitary ACTH release and de novo adrenal StAR synthesis

    PubMed Central

    Boyd, Kevin N.; Kumar, Sandeep; O'Buckley, Todd K.; Porcu, Patrizia; Morrow, A. Leslie

    2011-01-01

    The mechanisms of ethanol actions that produce its behavioral sequelae involve the synthesis of potent GABAergic neuroactive steroids, specifically the GABAergic metabolites of progesterone, (3α,5α)-3-hydroxypregnan-20-one (3α,5α-THP), and deoxycorticosterone, (3α,5α)-3,21-dihydroxypregnan-20-one. We investigated the mechanisms that underlie the effect of ethanol on adrenal steroidogenesis. We found that ethanol effects on plasma pregnenolone, progesterone, 3α,5α-THP and cortical 3α,5α-THP are highly correlated, exhibit a threshold of 1.5 g/kg, but show no dose dependence. Ethanol increases plasma adrenocorticotropic hormone (ACTH), adrenal steroidogenic acute regulatory protein (StAR), and adrenal StAR phosphorylation, but does not alter levels of other adrenal cholesterol transporters. The inhibition of ACTH release, de novo adrenal StAR synthesis or cytochrome P450 side chain cleavage activity prevents ethanol-induced increases in GABAergic steroids in plasma and brain. ACTH release and de novo StAR synthesis are independently regulated following ethanol administration and both are necessary, but not sufficient, for ethanol-induced elevation of plasma and brain neuroactive steroids. As GABAergic steroids contribute to ethanol actions and ethanol sensitivity, the mechanisms of this effect of ethanol may be important factors that contribute to the behavioral actions of ethanol and risk for alcohol abuse disorders. PMID:20021565

  16. Use of radioguided surgery with [111In]-pentetreotide in the management of an ACTH-secreting bronchial carcinoid causing ectopic Cushing's syndrome.

    PubMed

    Grossrubatscher, E; Vignati, F; Dalino, P; Possa, M; Belloni, P A; Vanzulli, A; Bramerio, M; Marocchi, A; Rossetti, O; Zurleni, F; Loli, P

    2005-01-01

    Intraoperative [111In]-pentetreotide scintigraphy with a hand-held gamma detector probe has recently been proposed to increase the intraoperative detection rate of small neuroendocrine tumors and their metastases. We report a case of a 28-yr-old woman with ectopic Cushing's syndrome due to an ACTH-secreting bronchial carcinoid, in whom the use of radioguided surgery improved disease management. At presentation, radiolabeled pentetreotide scintigraphy was the only procedure able to detect the ectopic source of ACTH. After radiologic confirmation, the patient underwent removal of a bronchial carcinoid, with disease persistence. After surgery, pentetreotide scintigraphy showed pathologic uptake in the mediastinum not previously detected at surgery and only subsequently confirmed by radiologic studies. Despite a second thoracic exploration, hormonal, scintigraphic, and radiological evidence of residual disease persisted. Radioguided surgery was then performed using a hand-held gamma probe 48 h after iv administration of a tracer dose of radiolabeled [111In-DTPA-D-Phe1]-pentetreotide, which permitted detection and removal of multiple residual mediastinal lymph node metastases. Clinical and radiologic cure, with no evidence of tracer uptake at pentetreotide scintigraphy, was subsequently observed. The use of an intraoperative gamma counter appears a promising procedure in the management of metastatic ACTH-secreting bronchial carcinoids. PMID:15816375

  17. Use of radioguided surgery with [111In]-pentetreotide in the management of an ACTH-secreting bronchial carcinoid causing ectopic Cushing's syndrome.

    PubMed

    Grossrubatscher, E; Vignati, F; Dalino, P; Possa, M; Belloni, P A; Vanzulli, A; Bramerio, M; Marocchi, A; Rossetti, O; Zurleni, F; Loli, P

    2005-01-01

    Intraoperative [111In]-pentetreotide scintigraphy with a hand-held gamma detector probe has recently been proposed to increase the intraoperative detection rate of small neuroendocrine tumors and their metastases. We report a case of a 28-yr-old woman with ectopic Cushing's syndrome due to an ACTH-secreting bronchial carcinoid, in whom the use of radioguided surgery improved disease management. At presentation, radiolabeled pentetreotide scintigraphy was the only procedure able to detect the ectopic source of ACTH. After radiologic confirmation, the patient underwent removal of a bronchial carcinoid, with disease persistence. After surgery, pentetreotide scintigraphy showed pathologic uptake in the mediastinum not previously detected at surgery and only subsequently confirmed by radiologic studies. Despite a second thoracic exploration, hormonal, scintigraphic, and radiological evidence of residual disease persisted. Radioguided surgery was then performed using a hand-held gamma probe 48 h after iv administration of a tracer dose of radiolabeled [111In-DTPA-D-Phe1]-pentetreotide, which permitted detection and removal of multiple residual mediastinal lymph node metastases. Clinical and radiologic cure, with no evidence of tracer uptake at pentetreotide scintigraphy, was subsequently observed. The use of an intraoperative gamma counter appears a promising procedure in the management of metastatic ACTH-secreting bronchial carcinoids.

  18. Relaxin-3 stimulates the neuro-endocrine stress axis via corticotrophin-releasing hormone.

    PubMed

    McGowan, B M; Minnion, J S; Murphy, K G; Roy, D; Stanley, S A; Dhillo, W S; Gardiner, J V; Ghatei, M A; Bloom, S R

    2014-05-01

    Relaxin-3 is a member of the insulin superfamily. It is expressed in the nucleus incertus of the brainstem, which has projections to the hypothalamus. Relaxin-3 binds with high affinity to RXFP1 and RXFP3. RXFP3 is expressed within the hypothalamic paraventricular nucleus (PVN), an area central to the stress response. The physiological function of relaxin-3 is unknown but previous work suggests a role in appetite control, stimulation of the hypothalamic-pituitary-gonadal axis and stress. Central administration of relaxin-3 induces c-fos expression in the PVN and increases plasma ACTH levels in rats. The aim of this study was to investigate the effect of central administration of human relaxin-3 (H3) on the hypothalamic-pituitary-adrenal (HPA) axis in male rodents in vivo and in vitro. Intracerebroventricular (i.c.v) administration of H3 (5 nmol) significantly increased plasma corticosterone at 30 min following injection compared with vehicle. Intra-PVN administration of H3 (1.8-1620 pmol) significantly increased plasma ACTH at 1620 pmol H3 and corticosterone at 180-1620 pmol H3 at 30 min following injection compared with vehicle. The stress hormone prolactin was also significantly raised at 15 min post-injection compared with vehicle. Treatment of hypothalamic explants with H3 (10-1000 nM) stimulated the release of corticotrophin-releasing hormone (CRH) and arginine vasopressin (AVP), but H3 had no effect on the release of ACTH from in vitro pituitary fragments. These results suggest that relaxin-3 may regulate the HPA axis, via hypothalamic CRH and AVP neurons. Relaxin-3 may act as a central signal linking nutritional status, reproductive function and stress.

  19. Infant Habituation to Visual and Auditory Stimulation.

    ERIC Educational Resources Information Center

    Dunn, Jane; Haskins, Ron

    A total of 14 infants participated in this study of the recovery of visual orienting by crossmodal stimulation when no new visual information was present. The locus of the crossmodal stimulation (auditory stimulation) was discriminable to the subject. Infants in three age groups were tested on three occasions each separated by 30 days. No…

  20. Diagnosis of myasthenia gravis: Comparison of anti-nicotinic acetyl choline receptor antibodies, repetitive nerve stimulation and Neostigmine tests at a tertiary neuro care centre in India, a ten year study.

    PubMed

    Patil, Shripad A; Bokoliya, Suresh C; Nagappa, Madhu; Taly, Arun B

    2016-03-15

    Anti-nicotinic AChR antibodies (Anti-nAChR antibodies), Repetitive Nerve Stimulation (RNS) and Neostigmine test are used for diagnosis of myasthenia gravis (MG). We compared their diagnostic agreement in a cohort of 486 MG patients over a period of ten years. Anti-nAChR antibodies, RNS and Neostigmine test showed positivity of 57.36%, 51.78%, and 93.4% respectively in ocular myasthenia and 93.77%, 82.35%, and 97.92% respectively in generalized myasthenia group. Neostigmine test showed higher positivity than anti-nAChR antibodies and RNS test in both groups. A marginal to fair agreement was observed between these tests highlighting their significance in the diagnosis of the disease.

  1. Caloric stimulation

    MedlinePlus

    ... temperature, it should cause fast, side-to-side eye movements called nystagmus. The test is done in the ... Rapid, side-to-side eye movements should occur when cold or warm water is placed into the ear. The eye movements should be similar on both ...

  2. Phosphodiesterase 11A (PDE11A) Gene Defects in Patients with ACTH-Independent Macronodular Adrenal Hyperplasia (AIMAH): Functional Variants May Contribute to Genetic Susceptibility of Bilateral Adrenal Tumors

    PubMed Central

    Vezzosi, Delphine; Libé, Rossella; Baudry, Camille; Rizk-Rabin, Marthe; Horvath, Anelia; Levy, Isaac; René-Corail, Fernande; Ragazzon, Bruno; Stratakis, Constantine A.; Vandecasteele, Grégoire

    2012-01-01

    Context: Phosphodiesterases (PDEs) are key regulatory enzymes of intracellular cAMP levels. PDE11A function has been linked to predisposition to adrenocortical tumors. Objective: The aim of the study was to study the PDE11A gene in a large cohort of patients with ACTH-independent macronodular adrenal hyperplasia (AIMAH) and in control subjects. Design: The PDE11A entire coding region was sequenced in 46 patients with AIMAH and 192 controls. Two variants found in AIMAH patients were transiently expressed in HEK 293 and adrenocortical H295R cells for further functional studies. Results: The frequency of all PDE11A variants was significantly higher among patients with AIMAH (28%) compared to controls (7.2%) (P = 5 × 10−5). Transfection of the two PDE11A variants found in AIMAH patients only (D609N or M878V) showed that cAMP levels were higher, after forskolin stimulation, in cells transfected with the PDE11A mutants, compared to cells transfected with the wild-type PDE11A in HEK 293 cells (P < 0.05). Moreover, transfection with mutants PDE11A increased transcriptional activity of a cAMP-response element reporter construct compared to wild-type PDE11A in HEK 293 cells (P < 0.0004 for D609N and P < 0.003 for M878V) and in the adrenocortical H295R cells (P < 0.05 for D609N and M878V). In addition, analysis of cAMP levels in intact living culture cells by fluorescence resonance energy transfer probes showed increased cAMP in forskolin-treated cells transfected with PDE11A variants compared with wild-type PDE11A (P < 0.05). Conclusion: We conclude that PDE11A genetic variants may increase predisposition to AIMAH. PMID:22996146

  3. Development of Point of Care Testing Device for Neurovascular Coupling From Simultaneous Recording of EEG and NIRS During Anodal Transcranial Direct Current Stimulation

    PubMed Central

    Jindal, Utkarsh; Sood, Mehak; Dutta, Anirban; Chowdhury, Shubhajit Roy

    2015-01-01

    This paper presents a point of care testing device for neurovascular coupling (NVC) from simultaneous recording of electroencephalogram (EEG) and near infrared spectroscopy (NIRS) during anodal transcranial direct current stimulation (tDCS). Here, anodal tDCS modulated cortical neural activity leading to hemodynamic response can be used to identify the impaired cerebral microvessels functionality. The impairments in the cerebral microvessels functionality may lead to impairments in the cerebrovascular reactivity (CVR), where severely reduced CVR predicts the chances of transient ischemic attack and ipsilateral stroke. The neural and hemodynamic responses to anodal tDCS were studied through joint imaging with EEG and NIRS, where NIRS provided optical measurement of changes in tissue oxy-(\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$HbO2)$ \\end{document} and deoxy-(\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$Hb$ \\end{document}) hemoglobin concentration and EEG captured alterations in the underlying neuronal current generators. Then, a cross-correlation method for the assessment of NVC underlying the site of anodal tDCS is presented. The feasibility studies on healthy subjects and stroke survivors showed detectable changes in the EEG and the NIRS responses to a 0.526 A/\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$\\mathrm{m}^{2}$ \\end{document} of anodal tDCS. The NIRS system

  4. Glucocorticoid Fast Feedback Inhibition of Stress-Induced ACTH Secretion in the Male Rat: Rate Independence and Stress-State Resistance.

    PubMed

    Osterlund, Chad D; Rodriguez-Santiago, Mariana; Woodruff, Elizabeth R; Newsom, Ryan J; Chadayammuri, Anjali P; Spencer, Robert L

    2016-07-01

    Normal glucocorticoid secretion is critical for physiological and mental health. Glucocorticoid secretion is dynamically regulated by glucocorticoid-negative feedback; however, the mechanisms of that feedback process are poorly understood. We assessed the temporal characteristics of glucocorticoid-negative feedback in vivo using a procedure for drug infusions and serial blood collection in unanesthetized rats that produced a minimal disruption of basal ACTH plasma levels. We compared the negative feedback effectiveness present when stress onset coincides with corticosterone's (CORT) rapidly rising phase (30 sec pretreatment), high plateau phase (15 min pretreatment), or restored basal phase (60 min pretreatment) as well as effectiveness when CORT infusion occurs after the onset of stress (5 min poststress onset). CORT treatment prior to stress onset acted remarkably fast (within 30 sec) to suppress stress-induced ACTH secretion. Furthermore, fast feedback induction did not require rapid increases in CORT at the time of stress onset (hormone rate independent), and those feedback actions were relatively long lasting (≥15 min). In contrast, CORT elevation after stress onset produced limited and delayed ACTH suppression (stress state resistance). There was a parallel stress-state resistance for CORT inhibition of stress-induced Crh heteronuclear RNA in the paraventricular nucleus but not Pomc heteronuclear RNA in the anterior pituitary. CORT treatment did not suppress stress-induced prolactin secretion, suggesting that CORT feedback is restricted to the control of hypothalamic-pituitary-adrenal axis elements of a stress response. These temporal, stress-state, and system-level features of in vivo CORT feedback provide an important physiological context for ex vivo studies of molecular and cellular mechanisms of CORT-negative feedback. PMID:27145013

  5. Glucocorticoid Fast Feedback Inhibition of Stress-Induced ACTH Secretion in the Male Rat: Rate Independence and Stress-State Resistance.

    PubMed

    Osterlund, Chad D; Rodriguez-Santiago, Mariana; Woodruff, Elizabeth R; Newsom, Ryan J; Chadayammuri, Anjali P; Spencer, Robert L

    2016-07-01

    Normal glucocorticoid secretion is critical for physiological and mental health. Glucocorticoid secretion is dynamically regulated by glucocorticoid-negative feedback; however, the mechanisms of that feedback process are poorly understood. We assessed the temporal characteristics of glucocorticoid-negative feedback in vivo using a procedure for drug infusions and serial blood collection in unanesthetized rats that produced a minimal disruption of basal ACTH plasma levels. We compared the negative feedback effectiveness present when stress onset coincides with corticosterone's (CORT) rapidly rising phase (30 sec pretreatment), high plateau phase (15 min pretreatment), or restored basal phase (60 min pretreatment) as well as effectiveness when CORT infusion occurs after the onset of stress (5 min poststress onset). CORT treatment prior to stress onset acted remarkably fast (within 30 sec) to suppress stress-induced ACTH secretion. Furthermore, fast feedback induction did not require rapid increases in CORT at the time of stress onset (hormone rate independent), and those feedback actions were relatively long lasting (≥15 min). In contrast, CORT elevation after stress onset produced limited and delayed ACTH suppression (stress state resistance). There was a parallel stress-state resistance for CORT inhibition of stress-induced Crh heteronuclear RNA in the paraventricular nucleus but not Pomc heteronuclear RNA in the anterior pituitary. CORT treatment did not suppress stress-induced prolactin secretion, suggesting that CORT feedback is restricted to the control of hypothalamic-pituitary-adrenal axis elements of a stress response. These temporal, stress-state, and system-level features of in vivo CORT feedback provide an important physiological context for ex vivo studies of molecular and cellular mechanisms of CORT-negative feedback.

  6. Blood Test: Testosterone

    MedlinePlus

    ... secretes two hormones (luteinizing hormone, or LH; and follicle-stimulating hormone, or FSH) that work together to ... TOPIC Blood Test: Luteinizing Hormone (LH) Blood Test: Follicle Stimulating Hormone (FSH) Blood Test: Estradiol Precocious Puberty ...

  7. Human Tissue Stimulator

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Neurodyne Corporation Human Tissue Stimulator (HTS) is a totally implantable system used for treatment of chronic pain and involuntary motion disorders by electrical stimulation. It was developed by Pacesetter Systems, Inc. in cooperation with the Applied Physics Laboratory. HTS incorporates a nickel cadmium battery, telemetry and command systems technologies of the same type as those used in NASA's Small Astronomy Satellite-3 in microminiature proportions so that the implantable element is the size of a deck of cards. The stimulator includes a rechargeable battery, an antenna and electronics to receive and process commands and to report on its own condition via telemetry, a wireless process wherein instrument data is converted to electrical signals and sent to a receiver where signals are presented as usable information. The HTS is targeted to nerve centers or to particular areas of the brain to provide relief from intractable pain or arrest involuntary motion. The nickel cadmium battery can be recharged through the skin. The first two HTS units were implanted last year and have been successful. Extensive testing is required before HTS can be made available for general use.

  8. A comparative study by age and gender of the pituitary adenoma and ACTH and alpha-MSH secretion in dogs with pituitary-dependent hyperadrenocorticism.

    PubMed

    Gallelli, M F; Cabrera Blatter, M F; Castillo, V

    2010-02-01

    Pituitary-dependent hyperadrenocorticism (PDH) is frequent in dogs. Little is known about its presentation in different age groups and its characteristics. Dividing the population under study (n=107) into three age groups we observed that 11.2% were young, 51.4% adults and 37.4% aged. Using magnetic resonance, pituitary tumours were intra-sellar (IS) in 30.8% and extra-sellar (ES) in 62.6% and the pars intermedia (PI) was affected in 6.5%. ES are predominant in females and IS in males (p<0.0001). In the adult-aged population, the ES and PI are predominant, while in the young, the IS predominate (p<0.0001). ACTH concentration was greater in the ES vs. IS (p<0.05). alpha-MSH did not present significant differences according to tumour size, showing a negative correlation (r=-0.47; p<0.01) vs. ACTH. Differences in adenoma size according to gender and their age-related frequency of apparition could be because of different origins of the corticotrophinoma.

  9. Clinical management of critically ill patients with Cushing's disease due to ACTH-secreting pituitary macroadenomas: effectiveness of presurgical treatment with pasireotide.

    PubMed

    Cannavo, S; Messina, E; Albani, A; Ferrau, F; Barresi, V; Priola, S; Esposito, F; Angileri, F

    2016-06-01

    The management of critically ill Cushing's disease (CD) patients is extremely challenging. Pasireotide is indicated for the treatment of CD patients when pituitary surgery is unfeasible or has not been curative, but no data are available about the use of this drug as pre-operative treatment in critically ill patients. We report the effects of presurgical pasireotide therapy in CD patients in whom hypercortisolism caused life-threatening hypokalemia, alkalosis, and cardio-respiratory complications precluding surgical approach. Clinical, biochemical, and radiological data of two critically ill patients with ACTH-secreting pituitary macroadenoma, before and during first-line presurgical pasireotide treatment (600 μg s.c. bid). During the first 21 days of treatment, pasireotide therapy induced a rapid, partial decrease of plasma ACTH, serum cortisol, and urinary free cortisol levels, with the consequent normalization of serum potassium concentration and arterial blood gases parameters, in both the patients. They did not experience unmanageable side effects and underwent endoscopic transsphenoidal surgery after 4 weeks of effective treatment. Pre-operative MRI evaluation did not show pituitary tumor shrinkage. Surgical cure of CD was obtained in the first patient, while debulking allowed the pharmacological control of hypercortisolism in the second case. We suggest that pasireotide can induce a rapid improvement of clinical and metabolic conditions in critically ill CD patients in whom surgical approach is considered hazardous and need to be delayed.

  10. Electrical stimulation in exercise training

    NASA Technical Reports Server (NTRS)

    Kroll, Walter

    1994-01-01

    muscle strength for over a century. Bigelow reported in 1894, for example, the use of electrical stimulation on a young man for the purpose of increasing muscle strength. Employing a rapidly alternating sinusoidal induced current and a dynamometer for strength testing, Bigelow reported that the total lifting capacity of a patient increased from 4328 pounds to 4639 pounds after only 25 minutes of stimulation. In 1965, Massey et al. reported on the use of an Isotron electrical stimulator that emitted a high frequency current. Interestingly enough, the frequencies used by Massey et al. and the frequencies used by Bigelow in 1894 were in the same range of frequencies reported by Kots as being the most effective in strength development. It would seem the Russian secret of high frequency electrical stimulation for strength development, then, is not a modern development at all.

  11. Anxiolytic-like effect of a selective and non-peptidergic melanocortin 4 receptor antagonist, MCL0129, in a social interaction test.

    PubMed

    Shimazaki, Toshiharu; Chaki, Shigeyuki

    2005-03-01

    The social interaction test is an animal behavioral test of anxiety. Brain melanocortins such as alpha-melanocyte stimulating hormone (alpha-MSH) and adrenocorticotropic hormone (ACTH) have anxiogenic effects in this test. Melanocortins have five receptor subtypes (MC1-MC5). Among them, MC3 and MC4 receptor are mainly expressed in the brain. We investigated the involvement of MC4 receptor in a social interaction test, using Ac-[Nle(4),Asp(5),D-Phe(7),Lys(10)]alpha-MSH-(4-10)-NH2 (MT II), an MC4 receptor agonist, and 1-[(S)-2-(4-fluorophenyl)-2-(4-isopropylpiperadin-1-yl)ethyl]-4-[4-(2-methoxynaphthalen-1-yl)butyl]piperazine (MCL0129), a selective and nonpeptide MC4 receptor antagonist. MT II dose-dependently and significantly reduced the time spent in social interaction. Acute administration of MCL0129 had no effect on the results of this test. In contrast, when given repeatedly for 1 week, MCL0129 significantly and dose-dependently increased the time spent in social interaction without affecting locomotor activity. These results suggest that MC4 receptor is involved in social interaction, and that MCL0129, an MC4 receptor antagonist, has an anxiolytic-like effect in this model.

  12. The adrenal gland and progesterone stimulates testicular steroidogenesis in the rat in vivo.

    PubMed

    Feek, C M; Tuzi, N L; Edwards, C R

    1989-04-01

    Administration of pharmacological doses of glucocorticoid to male rats in vivo suppresses adrenal steroidogenesis and inhibits testicular steroidogenesis by inhibiting the anterior pituitary secretion of LH. In contrast, administration of ACTH to these pharmacologically-suppressed rats stimulates the adrenal secretion of progesterone and testicular steroidogenesis. The mechanism by which ACTH increases testicular steroidogenesis is dependent on the presence of the adrenal gland and is reproduced by the administration of progesterone. The conclusion from these data is that the adrenal gland has an important role in generating external signals that modulate the hypothalamic-pituitary-gonadal axis in male rats. The adrenal secretion of glucocorticoid acts as a negative signal to testicular steroidogenesis whereas progesterone acts as a positive signal. The adrenal secretion of progesterone and its conversion to testosterone by steroidogenic enzymes in the cytoplasm of the Leydig cell may provide an alternative pathway for testosterone biosynthesis and may account for the increased plasma testosterone levels during the acute phase of stress and mating.

  13. Optical Stimulation of Neurons

    PubMed Central

    Thompson, Alexander C.; Stoddart, Paul R.; Jansen, E. Duco

    2014-01-01

    Our capacity to interface with the nervous system remains overwhelmingly reliant on electrical stimulation devices, such as electrode arrays and cuff electrodes that can stimulate both central and peripheral nervous systems. However, electrical stimulation has to deal with multiple challenges, including selectivity, spatial resolution, mechanical stability, implant-induced injury and the subsequent inflammatory response. Optical stimulation techniques may avoid some of these challenges by providing more selective stimulation, higher spatial resolution and reduced invasiveness of the device, while also avoiding the electrical artefacts that complicate recordings of electrically stimulated neuronal activity. This review explores the current status of optical stimulation techniques, including optogenetic methods, photoactive molecule approaches and infrared neural stimulation, together with emerging techniques such as hybrid optical-electrical stimulation, nanoparticle enhanced stimulation and optoelectric methods. Infrared neural stimulation is particularly emphasised, due to the potential for direct activation of neural tissue by infrared light, as opposed to techniques that rely on the introduction of exogenous light responsive materials. However, infrared neural stimulation remains imperfectly understood, and techniques for accurately delivering light are still under development. While the various techniques reviewed here confirm the overall feasibility of optical stimulation, a number of challenges remain to be overcome before they can deliver their full potential. PMID:26322269

  14. Electrical stimulation and motor recovery.

    PubMed

    Young, Wise

    2015-01-01

    stimulation (FES) has long been used to activate sacral nerves to treat bladder and pelvic dysfunction and to augment motor function. In theory, FES should facilitate synaptic formation and motor recovery after regenerative therapies. Upcoming clinical trials provide unique opportunities to test the theory. PMID:25646771

  15. Observations on the effects of vibration and noise on plasma ACTH and zinc levels, pregnancy and respiration rate in the guineapig.

    PubMed

    Bailey, K J; Stephens, D B; Delaney, C E

    1986-04-01

    The responses of female guineapigs to vibration and noise were examined with the use of an apparatus designed to simulate transport. Peak levels of plasma ACTH and zinc concentrations were attained after 4 min of exposure to vibration and 80-90 dB of noise. The respiration rate, normally around 90/min, was increased to 103/min when the animals were moved (while still in their cages) to the experimental area; it rose to 129/min when the apparatus was switched on to expose the animals to vibration and noise. Those left adjacent to the apparatus and exposed to noise alone elevated their respiration rates to 115/min. Respiration rates returned to normal within 2.5 h. There was no apparent effect on the maintenance of pregnancy, gestation length, litter size or post-partum growth of the young born to guineapigs exposed to this vibration and noise for a period of 1 h at mid-term.

  16. Gradual loss of ACTH due to a novel mutation in LHX4: comprehensive mutation screening in Japanese patients with congenital hypopituitarism.

    PubMed

    Takagi, Masaki; Ishii, Tomohiro; Inokuchi, Mikako; Amano, Naoko; Narumi, Satoshi; Asakura, Yumi; Muroya, Koji; Hasegawa, Yukihiro; Adachi, Masanori; Hasegawa, Tomonobu

    2012-01-01

    Mutations in transcription factors genes, which are well regulated spatially and temporally in the pituitary gland, result in congenital hypopituitarism (CH) in humans. The prevalence of CH attributable to transcription factor mutations appears to be rare and varies among populations.This study aimed to define the prevalence of CH in terms of nine CH-associated genes among Japanese patients. We enrolled 91 Japanese CH patients for DNA sequencing of POU1F1, PROP1, HESX1, LHX3, LHX4, SOX2, SOX3, OTX2, and GLI2. Additionally, gene copy numbers for POU1F1, PROP1, HESX1, LHX3, and LHX4 were examined by multiplex ligation-dependent probe amplification. The gene regulatory properties of mutant LHX4 proteins were characterized in vitro. We identified two novel heterozygous LHX4 mutations, namely c.249-1G>A, p.V75I, and one common POU1F1 mutation, p.R271W. The patient harboring the c.249-1G>A mutation exhibited isolated growth hormone deficiency at diagnosis and a gradual loss of ACTH, whereas the patient with the p.V75I mutation exhibited multiple pituitary hormone deficiency. In vitro experiments showed that both LHX4 mutations were associated with an impairment of the transactivation capacities of POU1F1 andαGSU, without any dominant-negative effects. The total mutation prevalence in Japanese CH patients was 3.3%. This study is the first to describe, a gradual loss of ACTH in a patient carrying an LHX4 mutation. Careful monitoring of hypothalamic-pituitary -adrenal function is recommended for CH patients with LHX4 mutations.

  17. Steroidogenic acute regulatory protein in eels: cDNA cloning and effects of ACTH and seawater transfer on its mRNA expression.

    PubMed

    Li, Yuan-You; Inoue, Koji; Takei, Yoshio

    2003-02-01

    Steroidogenic acute regulatory protein (StAR) is a key molecule for steroid production by translocating cholesterol from the outer to inner mitochondrial membrane. Two cDNAs of different length encoding StAR was cloned from the head kidney of the eel (Anguilla japonica). In the 3'-untranslated region (UTR) of the longer cDNA, two putative polyadenylation signals were found. The shorter one differed from the longer one solely by the lack of middle of 3'-UTR including the first polyadenylation signal. Reverse transcription-polymerase chain reaction (RT-PCR) that differentiates the two mRNAs showed that the ratio of the two was highly variable among individuals, and no preferential expression was detected between freshwater and seawater eels. The predicted protein consists of 285 amino acid residues with 64-83% identity to other StARs thus far obtained. RT-PCR analyses revealed that eel StAR mRNA was expressed abundantly in the head kidney and gonad, and faintly in the brain; but no expression was detected in the gill, heart, liver, intestine, kidney and skeletal muscle. Plasma cortisol concentration increased, but StAR mRNA content in the head kidney did not change, 3 and 24 h after transfer of freshwater eels to seawater, indicating that the transcriptional regulation of StAR may not be involved in cortisol production after seawater transfer. However, ACTH elevated both plasma cortisol and StAR mRNA levels in the head kidney 1.5 and 4.5 h after injection. Thus, the steroidogenic effect of ACTH is mediated by increased StAR production as observed in mammals. PMID:12655184

  18. Steroidogenic acute regulatory protein in eels: cDNA cloning and effects of ACTH and seawater transfer on its mRNA expression.

    PubMed

    Li, Yuan-You; Inoue, Koji; Takei, Yoshio

    2003-02-01

    Steroidogenic acute regulatory protein (StAR) is a key molecule for steroid production by translocating cholesterol from the outer to inner mitochondrial membrane. Two cDNAs of different length encoding StAR was cloned from the head kidney of the eel (Anguilla japonica). In the 3'-untranslated region (UTR) of the longer cDNA, two putative polyadenylation signals were found. The shorter one differed from the longer one solely by the lack of middle of 3'-UTR including the first polyadenylation signal. Reverse transcription-polymerase chain reaction (RT-PCR) that differentiates the two mRNAs showed that the ratio of the two was highly variable among individuals, and no preferential expression was detected between freshwater and seawater eels. The predicted protein consists of 285 amino acid residues with 64-83% identity to other StARs thus far obtained. RT-PCR analyses revealed that eel StAR mRNA was expressed abundantly in the head kidney and gonad, and faintly in the brain; but no expression was detected in the gill, heart, liver, intestine, kidney and skeletal muscle. Plasma cortisol concentration increased, but StAR mRNA content in the head kidney did not change, 3 and 24 h after transfer of freshwater eels to seawater, indicating that the transcriptional regulation of StAR may not be involved in cortisol production after seawater transfer. However, ACTH elevated both plasma cortisol and StAR mRNA levels in the head kidney 1.5 and 4.5 h after injection. Thus, the steroidogenic effect of ACTH is mediated by increased StAR production as observed in mammals.

  19. The 'Trier Social Stress Test'--a tool for investigating psychobiological stress responses in a laboratory setting.

    PubMed

    Kirschbaum, C; Pirke, K M; Hellhammer, D H

    1993-01-01

    This paper describes a protocol for induction of moderate psychological stress in a laboratory setting and evaluates its effects on physiological responses. The 'Trier Social Stress Test' (TSST) mainly consists of an anticipation period (10 min) and a test period (10 min) in which the subjects have to deliver a free speech and perform mental arithmetic in front of an audience. In six independent studies this protocol has been found to induce considerable changes in the concentration of ACTH, cortisol (serum and saliva), GH, prolactin as well as significant increases in heart rate. As for salivary cortisol levels, the TSST reliably led to 2- to 4-fold elevations above baseline with similar peak cortisol concentrations. Studies are summarized in which TSST-induced cortisol increases elucidated some of the multiple variables contributing to the interindividual variation in adrenocortical stress responses. The results suggest that gender, genetics and nicotine consumption can influence the individual's stress responsiveness to psychological stress while personality traits showed no correlation with cortisol responses to TSST stimulation. From these data we conclude that the TSST can serve as a tool for psychobiological research. PMID:8255414

  20. Electrocutaneous stimulation system for Braille reading.

    PubMed

    Echenique, Ana Maria; Graffigna, Juan Pablo; Mut, Vicente

    2010-01-01

    This work is an assistive technology for people with visual disabilities and aims to facilitate access to written information in order to achieve better social inclusion and integration into work and educational activities. Two methods of electrical stimulation (by current and voltage) of the mechanoreceptors was tested to obtain tactile sensations on the fingertip. Current and voltage stimulation were tested in a Braille cell and line prototype, respectively. These prototypes are evaluated in 33 blind and visually impaired subjects. The result of experimentation with both methods showed that electrical stimulation causes sensations of touch defined in the fingertip. Better results in the Braille characters reading were obtained with current stimulation (85% accuracy). However this form of stimulation causes uncomfortable sensations. The latter feeling was minimized with the method of voltage stimulation, but with low efficiency (50% accuracy) in terms of identification of the characters. We concluded that electrical stimulation is a promising method for the development of a simple and unexpensive Braille reading system for blind people. We observed that voltage stimulation is preferred by the users. However, more experimental tests must be carry out in order to find the optimum values of the stimulus parameters and increase the accuracy the Braille characters reading.

  1. Epidermal growth factor and gonadotropin-releasing hormone stimulate proliferation of enriched population of gonadotropes.

    PubMed

    Childs, G V; Unabia, G

    2001-02-01

    Recent studies of epidermal growth factor (EGF) receptors on gonadotropes show that they appear early in the estrous cycle on immature gonadotropes, most of which could be identified by LH messenger RNA only. As diestrous gonadotropes translate the messenger RNAs, the percentages of LH and FSH cells with EGF receptors increase to reach a peak during proestrus. To learn more about the function of EGF in gonadotrope regulation, parallel studies of its mitogenic potential were conducted. To test this in a cell growth assay, we initially developed a protocol for enrichment of gonadotropes by counterflow centrifugation (elutriation). Analysis of immunolabeled cells in the enriched fraction showed that the population contained 90-95% cells with LH and/or FSH antigens. Less than 4% have TSH or PRL antigens, and less than 7% have ACTH antigens. About 15% of the enriched population expressed GH antigens in male rats and nearly 30% of the population express GH in females. This agrees with the known hormone storage overlap between these cells, especially in proestrous female rats. The MTT cell growth/cell death assay was then used to test the mitogenic potential of EGF, GnRH, and activin. This assay showed a linear relationship between plated cell numbers and optical density of the media after the MTT reaction was run. The enriched gonadotropes were plated in 96-microwell trays and grown for 3-4 days in the presence of defined media alone (no serum), or defined media containing 0.5-10 ng/ml EGF, 0.5-1 nM GnRH, 60 ng/ml activin or two of these factors. In all of the 12 experiments, each of the factors stimulated a 3- to 10-fold increase in optical density values, depending on the dose of the stimulating factor. The effects of any two factors were not additive. Because the MTT assays do not discriminate between mitogenic effects and enhanced cell survival, a second group of tests was run with mixed cultures of pituitary cells from diestrous female rats. These cells were

  2. The value of electrical stimulation as an exercise training modality

    NASA Technical Reports Server (NTRS)

    Currier, Dean P.; Ray, J. Michael; Nyland, John; Noteboom, Tim

    1994-01-01

    Voluntary exercise is the traditional way of improving performance of the human body in both the healthy and unhealthy states. Physiological responses to voluntary exercise are well documented. It benefits the functions of bone, joints, connective tissue, and muscle. In recent years, research has shown that neuromuscular electrical stimulation (NMES) simulates voluntary exercise in many ways. Generically, NMES can perform three major functions: suppression of pain, improve healing of soft tissues, and produce muscle contractions. Low frequency NMES may gate or disrupt the sensory input to the central nervous system which results in masking or control of pain. At the same time NMES may contribute to the activation of endorphins, serotonin, vasoactive intestinal polypeptides, and ACTH which control pain and may even cause improved athletic performances. Soft tissue conditions such as wounds and inflammations have responded very favorably to NMES. NMES of various amplitudes can induce muscle contractions ranging from weak to intense levels. NMES seems to have made its greatest gains in rehabilitation where directed muscle contractions may improve joint ranges of motion correct joint contractures that result from shortening muscles; control abnormal movements through facilitating recruitment or excitation into the alpha motoneuron in orthopedically, neurologically, or healthy subjects with intense sensory, kinesthetic, and proprioceptive information; provide a conservative approach to management of spasticity in neurological patients; by stimulation of the antagonist muscle to a spastic muscle stimulation of the agonist muscle, and sensory habituation; serve as an orthotic substitute to conventional bracing used with stroke patients in lieu of dorsiflexor muscles in preventing step page gait and for shoulder muscles to maintain glenohumeral alignment to prevent subluxation; and of course NMES is used in maintaining or improving the performance or torque producing

  3. Blood Test: Estradiol

    MedlinePlus

    ... Testosterone Blood Test: Luteinizing Hormone (LH) Blood Test: Follicle Stimulating Hormone (FSH) Understanding Early Sexual Development Precocious Puberty Understanding Puberty Endocrine System Getting a ...

  4. Peripheral nerve stimulation: definition.

    PubMed

    Abejón, David; Pérez-Cajaraville, Juan

    2011-01-01

    Recently, there has been a tremendous evolution in the field of neurostimulation, both from the technological point of view and from development of the new and different indications. In some areas, such as peripheral nerve stimulation, there has been a boom in recent years due to the variations in the surgical technique and the improved results documented by in multiple published papers. All this makes imperative the need to classify and define the different types of stimulation that are used today. The confusion arises when attempting to describe peripheral nerve stimulation and subcutaneous stimulation. Peripheral nerve stimulation, in its pure definition, involves implanting a lead on a nerve, with the aim to produce paresthesia along the entire trajectory of the stimulated nerve.

  5. Predicting the clinical outcome of stimulant medication in pediatric attention-deficit/hyperactivity disorder: data from quantitative electroencephalography, event-related potentials, and a go/no-go test

    PubMed Central

    Ogrim, Geir; Kropotov, Juri; Brunner, Jan Ferenc; Candrian, Gian; Sandvik, Leiv; Hestad, Knut A

    2014-01-01

    Background We searched for predictors of the clinical outcome of stimulant medication in pediatric attention-deficit/hyperactivity disorder (ADHD), emphasizing variables from quantitative electroencephalography, event-related potentials (ERPs), and behavioral data from a visual go/no-go test. Methods Nineteen-channel electroencephalography (EEG) was recorded during the resting state in eyes-open and eyes-closed conditions and during performance of the cued go/no-go task in 98 medication-naïve ADHD patients aged 7–17 years and in 90 controls with the same age and sex distribution as the patients. For patients, the recording was followed by a systematic trial on stimulant medication lasting at least 4 weeks. Based on data from rating scales and interviews, two psychologists who were blind to the electrophysiological results independently rated the patients as responders (REs) (N=74) or non-responders (non-REs) (N=24). Using a logistic regression model, comparisons were made between REs and non-REs on the EEG spectra, ERPs (cue P3, contingent negative variation, and P3 no-go of the ERP waves and independent components [ICs] extracted from these waves), reaction time, reaction time variability, number of commission and omission errors, intelligence quotient, age, sex, ADHD subtype, and comorbidities. Results The two groups differed significantly on eight of the variables, with effect sizes (Cohen’s d) ranging from 0.49 to 0.76. In the multivariate logistic regression analysis, only three of these variables were significantly associated with clinical outcome. The amplitude of the IC cue P3, which has a parietal–occipital distribution, was normal in REs but significantly smaller in non-REs, whereas the centrally distributed IC P3 no-go early was smaller in REs than in non-REs and controls. In addition, the REs had more power in the EEG theta band. A quartile-based index was calculated using these three variables. The group with the lowest scores comprised only 36

  6. Stimulant Use Disorders.

    PubMed

    Park, Taryn M; Haning, William F

    2016-07-01

    Compared with other illicit substances, stimulants are not commonly used by adolescents; however, they represent a serious concern regarding substance use among youths. This article uses methamphetamine as a model for stimulant use in adolescents; cocaine and prescription stimulants are also mentioned. Methamphetamine use among adolescents and young adults is a serious health concern with potentially long-term physical, cognitive, and psychiatric consequences. Brain development and the effects of misusing stimulants align such that usage in adolescents can more dangerous than during adulthood. It seems helpful to keep in mind the differences between adolescents and young adults when implementing interventions. PMID:27338967

  7. Modulation of ovine fetal adrenocorticotropin secretion by androstenedione and 17beta-estradiol.

    PubMed

    Saoud, C J; Wood, C E

    1997-04-01

    Parturition in sheep is initiated by increases in activity of the fetal hypothalamic-pituitary-adrenal axis. We have previously reported that cortisol negative feedback efficacy is decreased at the end of gestation. The present study was designed to test the hypothesis that increasing plasma estrogen and/or androgen concentrations in the fetus might increase plasma adrenocorticotropic hormone (ACTH) concentration, either by stimulating ACTH secretion or by altering the negative feedback effect of cortisol on ACTH. Fetal sheep were chronically catheterized and treated with no steroid (control), 17beta-estradiol, or androstenedione (each approximately 0.24 mg/day). After catheterization and implantation of steroid pellet, fetuses were subjected to two short (10 min) periods of sodium nitroprusside-induced hypotension with or without pretreatment with intravenous infusion of hydrocortisone sodium succinate (0.5 microg/min) to test fetal ACTH responsiveness to stress and cortisol negative feedback efficacy. Estradiol treatment significantly increased basal plasma ACTH and cortisol concentrations relative to control fetuses but did not interfere with the inhibition of ACTH secretion by cortisol. Fetal plasma ACTH responses to hypotension were significantly suppressed approximately 60% in both control and estradiol-treated groups. Androstenedione treatment significantly increased basal fetal plasma ACTH and decreased basal fetal plasma cortisol concentration. Androstenedione did not alter stimulated levels of fetal ACTH but did block the inhibition of stimulated ACTH by cortisol. We conclude that increased fetal cortisol and ACTH secretion at the end of gestation may be due to the combined effects of the gonadal steroids in that estradiol increases basal plasma ACTH secretion while androstenedione reduces cortisol negative feedback efficacy.

  8. Sedating pediatric dental patients by oral ketamine with alternating bi-lateral stimulation of eye movement desensitization and minimizing adverse reaction of ketamine by acupuncture and Bi-Digital O-Ring Test.

    PubMed

    Lu, Dominic P; Wu, Ping-Shi; Lu, Winston I

    2012-01-01

    Ketamine, besides being an anesthetic agent, is also a strong analgesic that can be especially useful for painful procedures. Vivid dreams and nightmare, considered as undesirable side effects of ketamine, are rarely encountered when administrated orally, making it one of the most desirable oral sedative for children because it partially protects the pharyngeal-laryngeal reflex. Besides, if used in recommended dosage, it does not suppress the cardiopulmonary function as most other sedatives do. Ketamine's bronchodilator effect makes it a good sedative for children with asthma, allergies, and hay fever. Alternating bi-lateral stimulation (ABLS) of eye movement desensitization, applying pre-operatively before ketamine was found to reduce the post-operative violent emergence and behavioral problems. Acupressure at P 6 (Neikuan) acupoint helps to decrease nausea and vomiting episodes by ketamine. 36 patients with history of unmanageable behavior were sedated with ketamine 3mg/kg and ABLS. To prevent possible adverse reaction, Bi-Digital O-Ring Test (BDORT) were used to test all patients. ABLS significantly decreased tearful separation from parent. It took 15 to 20 minutes for ketamine to take effect, peak effect took 20 to 25 minutes. Working time ranged from 20 to 40 minutes. Post-operative recovery was more pleasant when ABLS was combined with ketamine, acupuncture/acupressure not only prevented vomiting and BDORT safeguard the patients from unpredictable untoward side effects but also promoting calmness. PMID:23156203

  9. Comparison of quadriceps inactivation between nerve and muscle stimulation.

    PubMed

    Place, Nicolas; Casartelli, Nicola; Glatthorn, Julia F; Maffiuletti, Nicola A

    2010-12-01

    We evaluated the use of direct muscle stimulation for quantifying quadriceps inactivation at different contraction levels as opposed to conventional twitch interpolation using nerve stimulation. Fourteen healthy volunteers were tested. Paired stimuli were delivered to the femoral nerve or to the quadriceps muscle belly during voluntary contractions ranging from 20% to 100% of maximum, and the amplitude of the superimposed doublet was quantified to investigate inactivation. Superimposed doublet for muscle and nerve stimulation, respectively between the range of 60% to 100% of maximum (e.g., at 100%, muscle stimulation was 14 ± 5 Nm and nerve stimulation was 15 ± 6 Nm). Despite higher current doses, muscle stimulation was associated with less discomfort than nerve stimulation (P < 0.05). Collectively, our data suggest that direct muscle stimulation could be used to assess quadriceps inactivation at maximal and quasi-maximal contraction levels as a valid alternative to motor nerve stimulation.

  10. [Electromagnetic urological stimulator].

    PubMed

    Zaslavskiĭ AOi; Markarov, G S; Gelis, Iu S

    1997-01-01

    The paper deals with an electromagnetic urological stimulator which generates a modulated low-frequency electromagnetic field of nonthermal intensity and its brief technical data. It presents a treatment regimen for urolithiasis and recommendations how to use the above therapeutical agent to stimulate urinary function in patients with urolithiasis in order to inoperatively eliminate urinary calculi and sand which form following extracorporeal shockwave lithotripsy.

  11. Stimulating your appetite.

    PubMed

    Whitfield, L

    1998-01-01

    A number of legal and illegal drugs can help stimulate appetite and are used for people with HIV to prevent wasting. Stimulating hunger is important because lower calorie intake and poor absorption of nutrients are associated with wasting. The uses and potential drawbacks of marijuana, thalidomide (Synovir), Marinol, and Megace are described. PMID:11365223

  12. Towards a Switched-Capacitor based Stimulator for efficient deep-brain stimulation.

    PubMed

    Vidal, Jose; Ghovanloo, Maysam

    2010-01-01

    We have developed a novel 4-channel prototype stimulation circuit for implantable neurological stimulators (INS). This Switched-Capacitor based Stimulator (SCS) aims to utilize charge storage and charge injection techniques to take advantage of both the efficiency of conventional voltage-controlled stimulators (VCS) and the safety and controllability of current-controlled stimulators (CCS). The discrete SCS prototype offers fine control over stimulation parameters such as voltage, current, pulse width, frequency, and active electrode channel via a LabVIEW graphical user interface (GUI) when connected to a PC through USB. Furthermore, the prototype utilizes a floating current sensor to provide charge-balanced biphasic stimulation and ensure safety. The stimulator was analyzed using an electrode-electrolyte interface (EEI) model as well as with a pair of pacing electrodes in saline. The primary motivation of this research is to test the feasibility and functionality of a safe, effective, and power-efficient switched-capacitor based stimulator for use in Deep Brain Stimulation. PMID:21095987

  13. Towards a Switched-Capacitor Based Stimulator for Efficient Deep-Brain Stimulation

    PubMed Central

    Vidal, Jose; Ghovanloo, Maysam

    2013-01-01

    We have developed a novel 4-channel prototype stimulation circuit for implantable neurological stimulators (INS). This Switched-Capacitor based Stimulator (SCS) aims to utilize charge storage and charge injection techniques to take advantage of both the efficiency of conventional voltage-controlled stimulators (VCS) and the safety and controllability of current-controlled stimulators (CCS). The discrete SCS prototype offers fine control over stimulation parameters such as voltage, current, pulse width, frequency, and active electrode channel via a LabVIEW graphical user interface (GUI) when connected to a PC through USB. Furthermore, the prototype utilizes a floating current sensor to provide charge-balanced biphasic stimulation and ensure safety. The stimulator was analyzed using an electrode-electrolyte interface (EEI) model as well as with a pair of pacing electrodes in saline. The primary motivation of this research is to test the feasibility and functionality of a safe, effective, and power-efficient switched-capacitor based stimulator for use in Deep Brain Stimulation. PMID:21095987

  14. TSH (Thyroid-Stimulating Hormone) Test

    MedlinePlus

    ... symptoms of a thyroid disorder , including hyperthyroidism or hypothyroidism . TSH is produced by the pituitary gland , a ... thyroid Monitor thyroid replacement therapy in people with hypothyroidism Monitor anti-thyroid treatment in people with hyperthyroidism ...

  15. Growth hormone stimulation test - series (image)

    MedlinePlus

    The growth hormone (GH) is a protein hormone released from the anterior pituitary gland under the control of the hypothalamus. ... performed on infants and children to identify human growth hormone (hGH) deficiency as a cause of growth retardation. ...

  16. Pseudomonas putida Stimulates Primordia on Agaricus bitorquis.

    PubMed

    Colauto, Nelson B; Fermor, Terry R; Eira, Augusto F; Linde, Giani A

    2016-04-01

    Casing layer is one step of Agaricus bisporus cultivation where there is a competitive environment with a high number of microorganisms and diversity interacting with mycelia. It is suggested that a minimal community of these microorganisms would be necessary to stimulate fructification. However, A. bisporus is not able to produce primordia in sterile casing layers or Petri dishes. Thus, the objective of this study was to characterize bacterial microbiota of casing layers from A. bisporus cultivation, isolate, identify and characterize the bacteria responsible for the stimulation of primordium and their action mechanism using Agaricus bitorquis as a primordium stimulation model. Bacterial and Pseudomonas spp. communities of different casing layers of A. bisporus cultivation were collected and quantified. It was concluded that Pseudomonas spp. corresponds to 75-85% of bacterial population of the casing layers in A. bisporus cultivation and among those 12% are Pseudomonas putida. Four biochemical assays were used to identify P. putida. In vitro primordium stimulation of living P. putida and non-living bacterial suspensions, after chemical or physical treatments, was tested using A. bitorquis as a primordium stimulation model. Primordium stimulation assay was registered by photographs, and micrographs of vertical cut of primordium were registered by scanning electron microscope. Interaction of living P. putida with A. bitorquis mycelia is capable of stimulating primordial instead of non-living bacterial suspensions. Stimulation of A. bitorquis primordia does not imply or is related to mycelial growth inhibition, but a hierarchical relation of primordium succession and development is suggested. PMID:26742772

  17. Primary hypercortisolism and phaeochromocytoma next to, but not related to, each other.

    PubMed

    Winter, Elizabeth M; Pereira, Alberto M; Corssmit, Eleonora P

    2016-01-01

    This is the first report of unilateral hypercortisolism and phaeochromocytoma that cannot be explained by medullary tumourigenic adrenocorticotropic hormone (ACTH) excretion. The patient was referred for an adrenal incidentaloma with hypertension but no Cushingoid features, disturbed glucose tolerance and osteopaenia. Additional testing revealed hypercortisolism with suppressed ACTH, and a right-sided phaeochromocytoma with typical radiographic appearance. Resection of the right adrenal completely normalised the clinical symptoms and biochemistry, and increased ACTH concentrations, implicating initial suppression. Histology revealed a tumour consisting of chromaffin cells, with only pre-existing cortical tissue containing groups of ACTH-positive cells. Recent human studies in primary Cushing's syndrome demonstrated that a paracrine effect of these aberrant cells, assumed to be Leydig cells in origin, results in hypercortisolism by stimulation of surrounding steroidogenic cells, leading to systemic ACTH suppression. We propose that 2 diagnoses within 1 adrenal, being phaeochromocytoma and autonomous cortisol overproduction due to adjoining aberrant ACTH-producing cells, explain the clinical picture. PMID:27073149

  18. Stimulation of the hypothalamo-pituitary-adrenal axis in the rat by three selective type-4 phosphodiesterase inhibitors: in vitro and in vivo studies

    PubMed Central

    Kumari, Meena; Cover, Patricia O; Poyser, Robert H; Buckingham, Julia C

    1997-01-01

    releasing hormone (ir-CRH-41) but lower concentrations of the drugs were without effect as also was BRL 61063 at 100 μM (P>0.05); the rank order of potency was thus BRL 61063>rolipram>denbufylline. The adenylyl cyclase activator forskolin (100 μM, P<0.01) also stimulated the release of ir-CRH-41, producing effects which were additive with those of rolipram and denbufylline but not with those of BRL 61063. The secretory responses to forskolin (100 μM) were accompanied by a highly significant increase in the cyclic AMP content of the hypothalamic tissue (P<0.005). Rolipram (10 μM) also significantly (P<0.05) elevated the hypothalamic cyclic AMP but denbufylline (10 mM) and BRL 61063 (10 μM) did not. However, all three PDE-inhibitors potentiated the rise in cyclic AMP induced by forskolin (P<0.05). None of the drugs tested, alone or in combination, modified the release of arginine vasopressin (ir-AVP) from the hypothalamus. Rolipram (100 μM), denbufylline (100 μM) and BRL 61063 (100 μM) stimulated the release of corticotrophin (ir-ACTH) from pituitary tissue in vitro (P<0.05) but in lower concentrations they were without significant effect. In addition, rolipram (10 μM, P<0.05), denbufylline (0.1 μM, P<0.05) and BRL 61063 (10 μM, P<0.05) potentiated the significant (P<0.05) rises in ir-ACTH secretion induced by forskolin (100 μM). Forskolin (100 μM) also produced a highly significant increase (P<0.01) in the tissue cyclic AMP content which was further potentiated by rolipram (10 μM), denbufylline (10 μM) and BRL 61063 (10 μM) which, alone did not affect the cyclic AMP content of the tissue. Since both denbufylline and BRL 61063 possess significant adenosine A1 receptor blocking activity, further studies examined the potential influence of these receptors on the secretion in vitro of CRH-41, AVP and ACTH. The release of ir-CRH-41 was increased significantly by adenosine deaminase (ADA, 5 u ml−1, P<0.05) and the A1-receptor

  19. Estrogen Regulation of Fetal Adrenal Cortical Zone-Specific Development in the Nonhuman Primate Impacts Adrenal Production of Androgen and Cortisol and Response to ACTH in Females in Adulthood.

    PubMed

    Pepe, Gerald J; Maniu, Adina; Aberdeen, Graham; Lynch, Terrie J; Albrecht, Eugene D

    2016-05-01

    We showed that the volume of the fetal zone of the fetal adrenal gland and serum dehydroepiandrosterone sulfate (DHAS) levels at term were increased in baboons in which estradiol levels were suppressed by treatment with aromatase inhibitor 4,4-[1,2,3-triazol-1yl-methylene] bis-benzonitrite (letrozole). The fetal zone remodels postnatally into the reticular zone and DHAS production, and serum levels decline with age. Therefore, we determined whether the trajectory of reticular zone DHAS secretion and response to ACTH were altered in offspring deprived of estrogen in utero. Female offspring were delivered to baboons untreated or treated daily throughout the second half of gestation with letrozole (estradiol reduced >95%) or letrozole plus estradiol and cortisol and DHAS determined in blood samples obtained bimonthly between 4 and 125 months and after iv bolus of ACTH. The slope/rate of decline in serum DHAS with advancing age was greater (P < .01) in letrozole-treated (-0.54 ± 0.005) than untreated (-0.32 ± 0.003) baboons and partially restored by letrozole-estradiol (-0.43 ± 0.004). Serum cortisol was similar and relatively constant in all offspring. Moreover, in letrozole-treated offspring, serum DHAS at 61-66, 67-95, and 96-125 months were lower (P < .05), and cortisol to DHAS ratio was greater (P < .05) than in untreated offspring. ACTH at high level increased cortisol and DHAS in untreated baboons and cortisol but not DHAS in letrozole-treated offspring. We propose that postnatal development of the primate adrenal cortex, including the decline in reticular zone DHAS production, response to ACTH and maintenance of cortisol to DHAS ratio with advancing age is modulated by exposure of the fetal adrenal to estradiol. PMID:26990066

  20. [Influence of prolonged treatment with octreotide on GH, IGF I, insulin, ACTH, cortisol, T3, T4 and TSH secretion in a case of congenital chylothorax].

    PubMed

    Bagnoli, F; Badii, S; Conte, M L; Toti, M S; De Felice, C; Bellieni, C V; Borlini, G; Tomasini, B; Zani, S

    2010-08-01

    Congenital chylothorax is a rare condition characterized by the accumulation of lymph fluid in the pleural space that causes respiratory and circulatory dysfunctions, immune deficiencies, hypoalbuminemia, electrolyte imbalance and alterations of the coagulation. Mortality rates are elevated and can rise to 50%. Therapy consists in conservative treatment based on thoracic drainage combined with total parenteral nutrition or use of low-fat high-protein diet supplemented with medium chain triglycerides. In case of failure surgical intervention may be considered. During the last years some authors have experienced the use of octreotide with doubtful results. In no case the drug impact on insulin, GH and cortisol secretion in neonatal age has been investigated and only in one case the effect on thyroid hormones has been assessed. We report the case of a 36-week baby with congenital chylothorax treated with octreotide for 42 days. The drug was well tolerated but hormonal level measurements showed a deep depression of insulin secretion unaccompanied by alterations of glucose levels. Levels of GH and TSH showed only a transitory decrease. ACTH and cortisol remained normal. At 5 months, the measurements of hormonal levels did not show significant alterations. It is not possible to determine if such a drug played an essential role in the solution of the pleural effusion, but it is important to emphasize that a prolonged treatment with octreotide has not caused, in our case, persistent hormonal alterations. PMID:20940674

  1. Inhibition of hormone-stimulated lipolysis by clofibrate. A possible mechanism for its hypolipidemic action.

    PubMed Central

    D'Costa, M A; Angel, A

    1975-01-01

    The present study was undertaken to investigate the mechanism of the antilipolytic action of clofibrate (p-chlorophenoxyisobutyrate). Clofibrate, in the dose range of 10-80 mg/199 ml, inhibited the initial rate of norepinephrine-stimulated lipolysis 17-44 percent in isolated rat fat cells. At a dose corresponding to therapeutic levels in vivo (10 mg/100 ml) clofibrate also inhibited hormone-stimulated lipolysis by 20-30 percent in fragments of human subcutaneous fat. Inhibition of lipolysis by clofibrate occurred at all concentrations of norepinephrine and ACTH (0.02-0.1 mug/ml) but did not occur with equilipolytic concentrations of dibutyryl cyclic AMP, suggesting a proximal site of action on the lipolytic sequence. Clofibrate reduced by 60 percent (315plus or minus40 vs. 120plus or minus25 pmol/g lipid; meanplus or minusSEM) the norepinephrine-stimulated initial rise in cyclic AMP, measured 10 min after addition of hormone. Because the antilipolytic effect occurred in the presence of glucose and without altering cellular ATP levels, the reduction in intracellular cyclic AMP levels could not be attributed to uncoupling of oxidative metabolism or to secondary effects of free fatty acid accumulation. In the secondary effects of free fatty acid accumulation. In the presence of procaine-HC1, which blocks hormone-stimulated lipolysis without inhibiting cyclic AMP accumulation, addition of clofibrate prevented the hormone-stimulated rise in cyclic AMP. Clofibrate did not affect the activity of the low-Km 3',5'-cyclic AMP phosphodiesterase in norepinephrine-stimulated adipocytes. These data suggest that the antilipolytic effect of clofibrate is due to its suppression of cyclic AMP production by inhibition of adenylate cyclase. The drug's hypolipidemic action may in part be explained by its antilipolytic effect, which deprives the liver of free fatty acid substrate for lipoprotein synthesis. Images PMID:162783

  2. Optically stimulated luminescence dosimetry

    NASA Astrophysics Data System (ADS)

    McKeever, Stephen W. S.

    2001-09-01

    Models and the conceptual framework necessary for an understanding of optically stimulated luminescence (OSL) are described. Examples of various OSL readout schemes are described, along with examples of the use of OSL in radiation dosimetry.

  3. Deep brain stimulation

    MedlinePlus

    ... the brain The neurostimulator, which puts out the electric current. The stimulator is similar to a heart pacemaker . It is usually placed under the skin near the collarbone, but may be ... pulses travel from the neurostimulator, along the extension ...

  4. Geothermal Well Stimulation

    SciTech Connect

    Campbell, D. A.; Morris, C. W.; Sinclair, A. R.; Hanold, R. J.; Vetter, O. J.

    1981-03-01

    The stimulation of geothermal wells presents some new and challenging problems. Formation temperatures in the 300-600 F range can be expected. The behavior of stimulation fluids, frac proppants, and equipment at these temperatures in a hostile brine environment must be carefully evaluated before performance expectations can be determined. In order to avoid possible damage to the producing horizon of the formation, high temperature chemical compatibility between the in situ materials and the stimulation materials must be verified. Perhaps most significant of all, in geothermal wells the required techniques must be capable of bringing about the production of very large amounts of fluid. This necessity for high flow rates represents a significant departure from conventional petroleum well stimulation and demands the creation of very high near-wellbore permeability and/or fractures with very high flow conductivity.

  5. Transcranial direct current stimulation: electrode montage in stroke.

    PubMed

    Mahmoudi, Hooman; Borhani Haghighi, Afshin; Petramfar, Peyman; Jahanshahi, Sepehr; Salehi, Zahra; Fregni, Felipe

    2011-01-01

    Neurophysiological and computer modelling studies have shown that electrode montage is a critical parameter to determine the neuromodulatory effects of transcranial direct current stimulation (tDCS). We tested these results clinically by systematically investigating optimal tDCS electrode montage in stroke. Ten patients received in a counterbalanced and randomised order the following conditions of stimulation (i) anodal stimulation of affected M1 (primary motor cortex) and cathodal stimulation of unaffected M1 ('bilateral tDCS'); (ii) anodal stimulation of affected M1 and cathodal stimulation of contralateral supraorbital area ('anodal tDCS'); (iii) cathodal stimulation of unaffected M1 and anodal stimulation of contralateral supraorbital area ('cathodal tDCS'); (iv) anodal stimulation of affected M1 and cathodal stimulation of contralateral deltoid muscle ('extra-cephalic tDCS') and (v) sham stimulation. We used the Jebsen-Taylor Test (JTT) as a widely accepted measure of upper limb function. Bilateral tDCS, anodal tDCS and cathodal tDCS were shown to be associated with significant improvements on the JTT. Placing the reference electrode in an extracephalic position and use of sham stimulation did not induce any significant effects. This small sham controlled cross-over clinical trial is important to provide additional data on the clinical effects of tDCS in stroke and for planning and designing future large tDCS trials in patients with stroke. PMID:21110732

  6. Transcranial direct current stimulation, implicit alcohol associations and craving.

    PubMed

    den Uyl, Tess E; Gladwin, Thomas E; Wiers, Reinout W

    2015-02-01

    Previous research has shown that stimulation of the left dorsolateral prefrontal cortex (DLPFC) enhances working memory (e.g. in the n-back task), and reduces craving for cigarettes and alcohol. Stimulation of the right inferior frontal gyrus (IFG) improves response inhibition. The underlying mechanisms are not clearly understood, nor is it known whether IFG stimulation also reduces craving. Here, we compared effects of DLPFC, IFG, and sham stimulation on craving in heavy drinkers in a small sample (n=41). We also tested effects of tDCS on overcoming response biases due to associations between alcohol and valence and alcohol and approach, using implicit association tests (IATs). Mild craving was reduced after DLPFC stimulation. Categorization of valence attribute words in the IAT was faster after DLPFC stimulation. We conclude that DLPFC stimulation can reduce craving in heavy drinkers, but found no evidence for tDCS induced changes in alcohol biases, although low power necessitates caution.

  7. Stimulation and suppression of aldosterone in plasma of normal man and in primary aldosteronism

    PubMed Central

    Horton, R.

    1969-01-01

    The effect of stimulating and suppressive influences on plasma aldosterone in normal man and in patients with primary aldosteronism were studied using a sensitive double-isotope derivative assay for aldosterone. In normal sitting subjects, values were 9.2±0.9 (SE) mμg/100 ml and in subjects supine for 1 hr plasma aldosterone was 5.2±0.4 (SE) mμg/100 ml. Adrenocorticotropic hormone (ACTH), 0.5 U/hr, produced a rise of 46.8±22 (SE) mμg which was similar to the 1-hr effect of an infusion of a synthetic ACTH (β1-24, Cortrosyn). Angiotensin II in pressor amounts also increased plasma aldosterone 21.5±2.9 (SE) without change in plasma cortisol, whereas a subpressor dose ([unk]) had minimal effect. Fludrocortisone, 1.2 mg/day for 3 days, suppressed plasma aldosterone levels to 1.8±0.7 (SE) mμg/100 ml in five normal sitting subjects (P < 0.01); however, dexamethasone, 2 mg/day for 1-2 days, did not lower aldosterone concentration in plasma. In six patients with primary aldosteronism, plasma aldosterone on a normal sodium diet was 39.1±4.4 (SE) which differed significantly from normal sitting or supine subjects (P < 0.001). In contrast to the normal subjects, neither a pressor infusion of angiotensin II for 1 hr, nor fludrocortisone, 1.2 mg/day for 3 days, impressively altered plasma aldosterone levels. This approach appears to be useful for the study of the acute physiology and control mechanisms of aldosterone production in normal and hypertensive man. PMID:4307457

  8. A fully implantable rodent neural stimulator

    NASA Astrophysics Data System (ADS)

    Perry, D. W. J.; Grayden, D. B.; Shepherd, R. K.; Fallon, J. B.

    2012-02-01

    The ability to electrically stimulate neural and other excitable tissues in behaving experimental animals is invaluable for both the development of neural prostheses and basic neurological research. We developed a fully implantable neural stimulator that is able to deliver two channels of intra-cochlear electrical stimulation in the rat. It is powered via a novel omni-directional inductive link and includes an on-board microcontroller with integrated radio link, programmable current sources and switching circuitry to generate charge-balanced biphasic stimulation. We tested the implant in vivo and were able to elicit both neural and behavioural responses. The implants continued to function for up to five months in vivo. While targeted to cochlear stimulation, with appropriate electrode arrays the stimulator is well suited to stimulating other neurons within the peripheral or central nervous systems. Moreover, it includes significant on-board data acquisition and processing capabilities, which could potentially make it a useful platform for telemetry applications, where there is a need to chronically monitor physiological variables in unrestrained animals.

  9. Deep Brain Stimulation using Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Jiles, David; Williams, Paul; Crowther, Lawrence; Iowa State University Team; Wolfson CentreMagnetics Team

    2011-03-01

    New applications for transcranial magnetic stimulation are developing rapidly for both diagnostic and therapeutic purposes. Therefore so is the demand for improved performance, particularly in terms of their ability to stimulate deeper regions of the brain and to do so selectively. The coil designs that are used presently are limited in their ability to stimulate the brain at depth and with high spatial focality. Consequently, any improvement in coil performance would have a significant impact in extending the usefulness of TMS in both clinical applications and academic research studies. New and improved coil designs have then been developed, modeled and tested as a result of this work. A large magnetizing coil, 300mm in diameter and compatible with a commercial TMS system has been constructed to determine its feasibility for use as a deep brain stimulator. The results of this work have suggested directions that could be pursued in order to further improve the coil designs.

  10. GPER1 stimulation alters posttranslational modification of RGSz1 and induces desensitization of 5-HT1A receptor signaling in the rat hypothalamus

    PubMed Central

    McAllister, Carrie E; Mi, Zhen; Mure, Minae; Li, Qian; Muma, Nancy A

    2014-01-01

    Hyperactivity of the hypothalamic-pituitary-adrenal axis is a consistent biological characteristic of depression and response normalization coincides with clinical responsiveness to antidepressant medications. Desensitization of serotonin 1A receptor (5-HT1AR) signaling in the hypothalamic paraventricular nucleus (PVN) follows selective serotonin reuptake inhibitor (SSRI) antidepressant treatment and contributes to the antidepressant response. Estradiol alone produces a partial desensitization of 5-HT1AR signaling, and synergizes with SSRIs to result in a complete and more rapid desensitization than with SSRIs alone as measured by a decrease in the oxytocin and adrenocorticotrophic hormone(ACTH) responses to 5-HT1AR stimulation. G protein-coupled estrogen receptor1 (GPER1) is necessary for estradiol-induced desensitization of 5-HT1AR signaling, although the underlying mechanisms are still unclear. We now find that stimulation of GPER1 with the selective agonist G-1 and non-selective stimulation of estrogen receptors dramatically alter isoform expression of a key component of the 5-HT1AR signaling pathway, RGSz1, a GTPase activating protein selective for Gαz, the Gα subunit necessary for 5-HT1AR-mediated hormone release. RGSz1 isoforms are differentially glycosylated, SUMOylated, and phosphorylated, and differentially distributed in subcellular organelles. High molecular weight RGSz1 is SUMOylated and glycosylated, localized to the detergent-resistant microdomain (DRM) of the cell membrane, and increased by estradiol and G-1 treatment. Because activated Gαz also localizes to the DRM, increased DRM-localized RGSz1 by estradiol and G-1could reduce Gαz activity, functionally uncoupling 5-HT1AR signaling. Peripheral G-1 treatment produced partial reduction in oxytocin and ACTH responses to 5-HT1AR-stimulation similar to direct injections into the PVN. Together, these results identify GPER1 and RGSz1 as novel targets for the treatment of depression. PMID:25402859

  11. Noninvasive techniques for probing neurocircuitry and treating illness: vagus nerve stimulation (VNS), transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS)

    PubMed Central

    George, Mark S; Aston-Jones, Gary

    2010-01-01

    Although the preceding chapters discuss much of the new knowledge of neurocircuitry of neuropsychiatric diseases, and an invasive approach to treatment, this chapter describes and reviews the noninvasive methods of testing circuit-based theories and treating neuropsychiatric diseases that do not involve implanting electrodes into the brain or on its surface. These techniques are transcranial magnetic stimulation, vagus nerve stimulation, and transcranial direct current stimulation. Two of these approaches have FDA approval as therapies. PMID:19693003

  12. Nucleus accumbens stimulation in pathological obesity.

    PubMed

    Harat, Marek; Rudaś, Marcin; Zieliński, Piotr; Birska, Julita; Sokal, Paweł

    2016-01-01

    One of the potential treatment methods of obesity is deep brain stimulation (DBS) of nucleus accumbens. We describe the case of 19 years old woman with hypothalamic obesity. She weighted 151.4 kg before DBS and the non-surgical methods proved to be inefficient. She was treated with implantation of DBS electrode to nucleus accumbens bilaterally. Results were measured with body mass index and neuropsychological tests. Follow-up was 14 months. Fourteen months after surgery weight was 138 kg, BMI was 48.3. Neuropsychological test results were intact. The presented case supports the thesis of treatment of obesity with nucleus accumbens stimulation. PMID:27154450

  13. Vagus Nerve Stimulation

    PubMed Central

    Howland, Robert H.

    2014-01-01

    The vagus nerve is a major component of the autonomic nervous system, has an important role in the regulation of metabolic homeostasis, and plays a key role in the neuroendocrine-immune axis to maintain homeostasis through its afferent and efferent pathways. Vagus nerve stimulation (VNS) refers to any technique that stimulates the vagus nerve, including manual or electrical stimulation. Left cervical VNS is an approved therapy for refractory epilepsy and for treatment resistant depression. Right cervical VNS is effective for treating heart failure in preclinical studies and a phase II clinical trial. The effectiveness of various forms of non-invasive transcutaneous VNS for epilepsy, depression, primary headaches, and other conditions has not been investigated beyond small pilot studies. The relationship between depression, inflammation, metabolic syndrome, and heart disease might be mediated by the vagus nerve. VNS deserves further study for its potentially favorable effects on cardiovascular, cerebrovascular, metabolic, and other physiological biomarkers associated with depression morbidity and mortality. PMID:24834378

  14. Effects of Sensory Modality Stimulation on the Dysarthria of Cerebral Palsy.

    ERIC Educational Resources Information Center

    Love, Russel J.

    To explore the efficacy of improving the dysarthria of cerebral palsy under conditions of aural stimulation, visual stimulation, and combined aural-visual stimulation, 22 subjects (aged 7.6 to 19.0 years) received intensive stimulation for word limitation for 22 consecutive school days. The 87 words of the Irwin Integrated Articulation Test were…

  15. New York Canyon Stimulation

    SciTech Connect

    Raemy, Bernard

    2012-06-21

    The New York Canyon Stimulation Project was to demonstrate the commercial application of Enhanced Geothermal System techniques in Buena Vista Valley area of Pershing County, Nevada. From October 2009 to early 2012, TGP Development Company aggressively implemented Phase I of Pre-Stimulation and Site/Wellbore readiness. This included: geological studies; water studies and analyses and procurement of initial permits for drilling. Oversubscription of water rights and lack of water needed for implementation of EGS were identified and remained primary obstacles. Despite extended efforts to find alternative solutions, the water supply circumstances could not be overcome and led TGP to determine a "No Go" decision and initiate project termination in April 2012.

  16. Muscle Stimulation Technology

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Under a Goddard Space Flight Center contract, Electrologic of America was able to refine the process of densely packing circuitry on personal computer boards, providing significant contributions to the closed-loop systems for the Remote Manipulator System Simulator. The microcircuitry work was then applied to the StimMaster FES Ergometer, an exercise device used to stimulate muscles suffering from paralysis. The electrical stimulation equipment was developed exclusively for V-Care Health Systems, Inc. Product still commercially available as of March 2002.

  17. [Design and Implementation of a Programmable Wireless Neural Stimulation System].

    PubMed

    Zhang, Zhang; Yu, Wencheng; Tan, Ye; Zeng, Jianmin; Xie, Guangjun

    2016-01-01

    The paper proposes and realizes a programmable wireless neural stimulation system which can be used as a solution of functional electrical stimulation to treat neural diseases. The system is composed of two parts: controller and neural stimulator. The controller can transmit pulse parameters to the stimulator wirelessly, and the stimulator can generate bidirectional pulses with charge balance. The simulator takes use of ADCs to sample on the bidirectional pulse output, which compared with preset amplitude to the DAC output voltage to realize the voltage calibration. Through the test, the whole system works stably and the output of the biphasic charge balanced circuit is definite. The stimulator output ranges from 0 to 5 V ajustably, and the frequency ranges from 1 Hz to 200 Hz ajustably, while the pulse width ranges from 500 μs to 1500 μs ajustably. The duration of the stimulation can be set from 10 s to 10 min. PMID:27197493

  18. Effect of neurovestibular stimulation on autonomic regulation

    NASA Technical Reports Server (NTRS)

    Costa, F.; Lavin, P.; Robertson, D.; Biaggioni, I.

    1995-01-01

    Conditions associated with nausea and vomiting, such as motion sickness or side effects of medications, are commonly associated with a clinical picture consistent with parasympathetic activation and sympathetic withdrawal. It can be postulated, therefore, that vestibular stimulation contributes to sympathetic withdrawal. To test this hypothesis five normal volunteers, 24-33 years old, were studied during caloric vestibular stimulation while monitoring muscle sympathetic nerve activity directly through a needle electrode placed in a peroneal nerve. The ear was irrigated with water at a flow rate of 450 ml/min and 37 degrees C. The water temperature was sequentially lowered by 7 degree C intervals until intolerable side effects developed or a temperature of 16 degrees C was reached. Nystagmus was induced in all subjects, but heart rate, blood pressure, muscle sympathetic nerve activity and plasma norepinephrine levels did not change significantly during or after caloric stimulation, even when the subjects felt dizzy and nauseated. No evidence of sympathetic withdrawal was observed in any subject either by muscle sympathetic nerve activity or plasma norepinephrine measurements. In conclusion, we have found that selective vestibular stimulation is not accompanied by significant changes in the sympathetic nervous system function. In particular, no sympathetic withdrawal was observed. It could be argued that lack of sympathetic stimulation is an inadequate response to the symptoms associated with caloric stimulation.

  19. What does galvanic vestibular stimulation stimulate?

    PubMed

    Wardman, Daniel L; Fitzpatrick, Richard C

    2002-01-01

    The technique of galvanic vestibular stimulation (GVS) has been used for a long time. The stimulus produces stereotyped automatic postural and ocular responses. The mechanisms underlying these responses are not understood although they are commonly attributed to altered otolith output. Based on animal studies, it seems reasonable to assume that vestibular afferents from the otoliths and semicircular canals are affected similarly by GVS. With this assumption, and anatomical knowledge of the vestibular apparatus, a model is developed to describe the expected responses of vestibular afferents to percutaneous GVS and the physiological implications of this altered sensory signal. Bilateral bipolar GVS, the most commonly used technique, should produce a canal signal consistent with a strong ear-down roll towards the cathodal side, a smaller nose-to-cathode yaw, but no pitch signal. Bilateral bipolar GVS should also produce an otolith signal consistent with tilt towards the cathodal side or a translational acceleration towards the anodal side. The expected responses for other configurations of GVS are also described. The model appears consistent with published data on the ocular and postural responses to GVS, and suggests other testable hypotheses concerning postural, ocular and perceptual responses to GVS.

  20. Transcranial brain stimulation: closing the loop between brain and stimulation

    PubMed Central

    Karabanov, Anke; Thielscher, Axel; Siebner, Hartwig Roman

    2016-01-01

    Purpose of review To discuss recent strategies for boosting the efficacy of noninvasive transcranial brain stimulation to improve human brain function. Recent findings Recent research exposed substantial intra- and inter-individual variability in response to plasticity-inducing transcranial brain stimulation. Trait-related and state-related determinants contribute to this variability, challenging the standard approach to apply stimulation in a rigid, one-size-fits-all fashion. Several strategies have been identified to reduce variability and maximize the plasticity-inducing effects of noninvasive transcranial brain stimulation. Priming interventions or paired associative stimulation can be used to ‘standardize’ the brain-state and hereby, homogenize the group response to stimulation. Neuroanatomical and neurochemical profiling based on magnetic resonance imaging and spectroscopy can capture trait-related and state-related variability. Fluctuations in brain-states can be traced online with functional brain imaging and inform the timing or other settings of transcranial brain stimulation. State-informed open-loop stimulation is aligned to the expression of a predefined brain state, according to prespecified rules. In contrast, adaptive closed-loop stimulation dynamically adjusts stimulation settings based on the occurrence of stimulation-induced state changes. Summary Approaches that take into account trait-related and state-related determinants of stimulation-induced plasticity bear considerable potential to establish noninvasive transcranial brain stimulation as interventional therapeutic tool. PMID:27224087

  1. Computer Games Functioning as Motivation Stimulants

    ERIC Educational Resources Information Center

    Lin, Grace Hui Chin; Tsai, Tony Kung Wan; Chien, Paul Shih Chieh

    2011-01-01

    Numerous scholars have recommended computer games can function as influential motivation stimulants of English learning, showing benefits as learning tools (Clarke and Dede, 2007; Dede, 2009; Klopfer and Squire, 2009; Liu and Chu, 2010; Mitchell, Dede & Dunleavy, 2009). This study aimed to further test and verify the above suggestion,…

  2. Electromechanical Nerve Stimulator

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

    1993-01-01

    Nerve stimulator applies and/or measures precisely controlled force and/or displacement to nerve so response of nerve measured. Consists of three major components connected in tandem: miniature probe with spherical tip; transducer; and actuator. Probe applies force to nerve, transducer measures force and sends feedback signal to control circuitry, and actuator positions force transducer and probe. Separate box houses control circuits and panel. Operator uses panel to select operating mode and parameters. Stimulator used in research to characterize behavior of nerve under various conditions of temperature, anesthesia, ventilation, and prior damage to nerve. Also used clinically to assess damage to nerve from disease or accident and to monitor response of nerve during surgery.

  3. Optically stimulated luminescence dosimetry

    NASA Astrophysics Data System (ADS)

    McKeever, Stephen W.

    1999-02-01

    Optically Stimulated Luminescence (OSL) dosimetry is attractive to the health physics and dosimetry community due to its all-optical character, fast data acquisition and the avoidance of heating the detector. Until recently there was no luminescent material sensitive enough to radiation, and at the same time suitable for stimulation with visible light, for use in this application. However, anion-deficient aluminum oxide doped with carbon (Al2O3:C) appears to be not only an extremely sensitive thermoluminescence (TL) material, but is also well-suited to OSL applications. Several OSL readout protocols have been suggested, including cw-OSL, pulsed OSL (POSL), and 'delayed' OSL (DOSL). The paper discusses the physical mechanisms that give rise to the OSL signals and the dependence of these signals upon absorbed dose. Example applications of the use of OSL from Al2O3:C in environmental radiation and ultraviolet-B dosimetry are discussed.

  4. Sacral nerve stimulation.

    PubMed

    Matzel, K E; Stadelmaier, U; Besendörfer, M

    2004-01-01

    The current concept of recruiting residual function of an inadequate pelvic organ by electrostimulation involves stimulation of the sacral spinal nerves at the level of the sacral canal. The rationale for applying SNS to fecal incontinence was based on clinical observations of its effect on bowel habits and anorectal continence function in urologic patients (increased anorectal angulation and anal canal closure pressure) and on anatomic considerations: dissection demonstrated a dual peripheral nerve supply of the striated pelvic floor muscles that govern these functions. Because the sacral spinal nerve site is the most distal common location of this dual nerve supply, stimulating here can elicit both functions. Since the first application of SNS in fecal incontinence in 1994, this technique has been improved, the patient selection process modified, and the spectrum of indications expanded. At present SNS has been applied in more than 1300 patients with fecal incontinence limited.

  5. Cognitive stimulation in brainstorming.

    PubMed

    Dugosh, K L; Paulus, P B; Roland, E J; Yang, H C

    2000-11-01

    Research on group brainstorming has demonstrated that it is less effective for generating large numbers of ideas than individual brainstorming, yet various scholars have presumed that group idea sharing should enhance cognitive stimulation and idea production. Three experiments examined the potential of cognitive stimulation in brainstorming. Experiments 1 and 2 used a paradigm in which individuals were exposed to ideas on audiotape as they were brainstorming, and Experiment 3 used the electronic brainstorming paradigm. Evidence was obtained for enhanced idea generation both during and after idea exposure. The attentional set of the participant and the content of the exposure manipulation (number of ideas, presence of irrelevant information) influenced this effect. These results are consistent with a cognitive perspective on group brainstorming.

  6. Stimulated Raman photoacoustic imaging

    PubMed Central

    Yakovlev, Vladislav V.; Zhang, Hao F.; Noojin, Gary D.; Denton, Michael L.; Thomas, Robert J.; Scully, Marlan O.

    2010-01-01

    Achieving label-free, molecular-specific imaging with high spatial resolution in deep tissue is often considered the grand challenge of optical imaging. To accomplish this goal, significant optical scattering in tissues has to be overcome while achieving molecular specificity without resorting to extrinsic labeling. We demonstrate the feasibility of developing such an optical imaging modality by combining the molecularly specific stimulated Raman excitation with the photoacoustic detection. By employing two ultrashort excitation laser pulses, separated in frequency by the vibrational frequency of a targeted molecule, only the specific vibrational level of the target molecules in the illuminated tissue volume is excited. This targeted optical absorption generates ultrasonic waves (referred to as stimulated Raman photoacoustic waves) which are detected using a traditional ultrasonic transducer to form an image following the design of the established photoacoustic microscopy. PMID:21059930

  7. Braille line using electrical stimulation

    NASA Astrophysics Data System (ADS)

    Puertas, A.; Purés, P.; Echenique, A. M.; Ensinck, J. P. Graffigna y. G.

    2007-11-01

    Conceived within the field of Rehabilitation Technologies for visually impaired persons, the present work aims at enabling the blind user to read written material by means of a tactile display. Once he is familiarized to operate this system, the user will be able to achieve greater performance in study, academic and job activities, thus achieving a rapid and easier social inclusion. The devise accepts any kind of text that is computer-loadable (documents, books, Internet information, and the like) which, through digital means, can be read as Braille text on the pad. This tactile display is composed of an electrodes platform that simulate, through stimulation the writing/reading Braille characters. In order to perceive said characters in similar way to the tactile feeling from paper material, the skin receptor of fingers are stimulated electrically so as to simulate the same pressure and depressions as those of the paper-based counterpart information. Once designed and developed, the display was tested with blind subjects, with relatively satisfactory results. As a continuing project, this prototype is currently being improved as regards.

  8. Suppression and facilitation of auditory neurons through coordinated acoustic and midbrain stimulation: investigating a deep brain stimulator for tinnitus

    NASA Astrophysics Data System (ADS)

    Offutt, Sarah J.; Ryan, Kellie J.; Konop, Alexander E.; Lim, Hubert H.

    2014-12-01

    Objective. The inferior colliculus (IC) is the primary processing center of auditory information in the midbrain and is one site of tinnitus-related activity. One potential option for suppressing the tinnitus percept is through deep brain stimulation via the auditory midbrain implant (AMI), which is designed for hearing restoration and is already being implanted in deaf patients who also have tinnitus. However, to assess the feasibility of AMI stimulation for tinnitus treatment we first need to characterize the functional connectivity within the IC. Previous studies have suggested modulatory projections from the dorsal cortex of the IC (ICD) to the central nucleus of the IC (ICC), though the functional properties of these projections need to be determined. Approach. In this study, we investigated the effects of electrical stimulation of the ICD on acoustic-driven activity within the ICC in ketamine-anesthetized guinea pigs. Main Results. We observed ICD stimulation induces both suppressive and facilitatory changes across ICC that can occur immediately during stimulation and remain after stimulation. Additionally, ICD stimulation paired with broadband noise stimulation at a specific delay can induce greater suppressive than facilitatory effects, especially when stimulating in more rostral and medial ICD locations. Significance. These findings demonstrate that ICD stimulation can induce specific types of plastic changes in ICC activity, which may be relevant for treating tinnitus. By using the AMI with electrode sites positioned with the ICD and the ICC, the modulatory effects of ICD stimulation can be tested directly in tinnitus patients.

  9. Cushing disease

    MedlinePlus

    ... much ACTH. ACTH stimulates production and release of cortisol, a stress hormone. Too much ACTH causes the adrenal glands to make too much cortisol. Cortisol is normally released during stressful situations. It ...

  10. Raft River well stimulation experiments: geothermal reservoir well stimulation program

    SciTech Connect

    Not Available

    1980-08-01

    The Geothermal Reservoir Well Stimulation Program (GRWSP) performed two field experiments at the Raft River KGRA in 1979. Wells RRGP-4 and RRGP-5 were selected for the hydraulic fracture stimulation treatments. The well selection process, fracture treatment design, field execution, stimulation results, and pre- and post-job evaluations are presented.

  11. Lymphocyte stimulation by soluble subcellular fractions.

    PubMed

    Pegrum, G D; Thompson, E A; Lewis, C M; Grant, V A

    1976-04-01

    Nuclear material can produce inhibition or stimulation of healty leucocytes under different experimental conditions, Reactivity could not be produced in cultures using intact nuclei and allogeneic lymphocytes. The effect of nuclear and cytoplasm fractions was compared with that of whole cells on intact healthy lymphocytes. The HLA activity in the individual fractions was assessed. Stimulation was produced by certain nuclear and cytoplasmic fractions and these were closely related to the peaks of HLA activity. The response to these fractions showed less activity than that achieved in conventional one way MLC tests.

  12. Somatostatin-14 and somatostatin-28 pretreatment down-regulate somatostatin-14 receptors and have biphasic effects on forskolin-stimulated cyclic adenosine, 3',5'-monophosphate synthesis and adrenocorticotropin secretion in mouse anterior pituitary tumor cells.

    PubMed

    Heisler, S; Srikant, C B

    1985-07-01

    Activation of somatostatin-14 (S-14) receptors on mouse AtT-20 pituitary tumor cells by S-14 or somatostatin-28 (S-28) inhibits forskolin-stimulated cAMP synthesis and ACTH secretion. In this study, the effects of prolonged exposure of cells to S-14 or S-28 was found to reduce, in a time- and concentration-dependent fashion, the density of S-14 receptors without affecting the affinity of these sites for [125I]Tyr11-S-14. This response was rapidly reversible after removal of peptide from incubation media. Additionally, S-14 and S-28 pretreatment also resulted in a time-dependent sensitizing effect on forskolin-stimulated cAMP formation and ACTH secretion which preceded S-14 receptor down-regulation. Enhancement of the forskolin response was concentration dependent, with maximal effects observed at 10(-8) M with either peptide. Higher pretreatment concentrations of S-14 resulted in an abolition of the enhanced biological response to forskolin; pretreatment with S-28 (10(-6) M) depressed forskolin- and (-)isoproterenol-induced cAMP formation below levels observed in nonpretreated cells. The enhancing effect of S-14 and S-28 required new protein synthesis, since it was partially blocked by cycloheximide; the depressor effect was independent of new protein synthesis. Both the enhanced and depressed forskolin responses after peptide pretreatment were reversible after withdrawal of S-14 or S-28; normalization of the forskolin response (cAMP formation and ACTH secretion) followed the return to control levels of S-14 receptor density. Pretreatment of cells with 10(-8) M or 10(-6) M S-28 increased and decreased, respectively, the ACTH secretory response to agonists which act in the absence of prior cAMP synthesis such as 8-bromo-cAMP, A-23187, and phorbol ester. The data suggest that S-14 receptor down-regulation is not causally associated with the sensitizing effects of S-14 and S-28 on adenylate cyclase and that the S-14 receptor may be also coupled to other effector

  13. Bipolar deep brain stimulation permits routine EKG, EEG, and polysomnography.

    PubMed

    Frysinger, Robert C; Quigg, Mark; Elias, W Jeffrey

    2006-01-24

    As the population of patients treated with deep brain stimulation (DBS) grows and the patients age, more will require routine or emergent electrophysiologic tests. DBS artifact may render these uninterpretable, whereas stopping DBS may release symptoms that confound evaluation. The authors find that monopolar, but not bipolar, stimulation produces significant artifact during EKG, EEG, and polysomnography.

  14. Stimulability: Relationships to Other Characteristics of Children's Phonological Systems

    ERIC Educational Resources Information Center

    Tyler, Ann A.; Macrae, Toby

    2010-01-01

    In honour of Miccio's memory, this article revisits the topic of stimulability in children with speech sound disorders (SSD). Eighteen children with SSD, aged 3;6-5;5 (M = 4;8), were tested for their system-wide stimulability, percentage consonants correct (PCC), phonetic inventory size, and oral- and speech-motor skills. Pearson Product Moment…

  15. 21 CFR 874.1800 - Air or water caloric stimulator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... vestibular function testing of a patient's body balance system. The vestibular stimulation of the... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Air or water caloric stimulator. 874.1800 Section 874.1800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  16. 21 CFR 874.1800 - Air or water caloric stimulator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... vestibular function testing of a patient's body balance system. The vestibular stimulation of the... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Air or water caloric stimulator. 874.1800 Section 874.1800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  17. Electrophysiological channel interactions using focused multipolar stimulation for cochlear implants

    NASA Astrophysics Data System (ADS)

    George, Shefin S.; Shivdasani, Mohit N.; Wise, Andrew K.; Shepherd, Robert K.; Fallon, James B.

    2015-12-01

    Objective. Speech intelligibility with existing multichannel cochlear implants (CIs) is thought to be limited by poor spatial selectivity and interactions between CI channels caused by overlapping activation with monopolar (MP) stimulation. Our previous studies have shown that focused multipolar (FMP) and tripolar (TP) stimulation produce more restricted neural activation in the inferior colliculus (IC), compared to MP stimulation. Approach. This study explored interactions in the IC produced by simultaneous stimulation of two CI channels. We recorded multi-unit neural activity in the IC of anaesthetized cats with normal and severely degenerated spiral ganglion neuron populations in response to FMP, TP and MP stimulation from a 14 channel CI. Stimuli were applied to a ‘fixed’ CI channel, chosen toward the middle of the cochlear electrode array, and the effects of simultaneously stimulating a more apical ‘test’ CI channel were measured as a function of spatial separation between the two stimulation channels and stimulus level of the fixed channel. Channel interactions were quantified by changes in neural responses and IC threshold (i.e., threshold shift) elicited by simultaneous stimulation of two CI channels, compared to stimulation of the test channel alone. Main results. Channel interactions were significantly lower for FMP and TP than for MP stimulation (p < 0.001), whereas no significant difference was observed between FMP and TP stimulation. With MP stimulation, threshold shifts increased with decreased inter-electrode spacing and increased stimulus levels of the fixed channel. For FMP and TP stimulation, channel interactions were found to be similar for different inter-electrode spacing and stimulus levels of the fixed channel. Significance. The present study demonstrates how the degree of channel interactions in a CI can be controlled using stimulation configurations such as FMP and TP; such knowledge is essential in enhancing CI function in complex

  18. Luteinizing hormone (LH) blood test

    MedlinePlus

    ICSH - blood test; Luteinizing hormone - blood test; Interstitial cell stimulating hormone - blood test ... to temporarily stop medicines that may affect the test results. Be sure to tell your provider about ...

  19. Neurophysiological responses to unpleasant stimuli (acute electrical stimulations and emotional pictures) are increased in patients with schizophrenia.

    PubMed

    Duval, Céline Z; Goumon, Yannick; Kemmel, Véronique; Kornmeier, Jürgen; Dufour, André; Andlauer, Olivier; Vidailhet, Pierre; Poisbeau, Pierrick; Salvat, Eric; Muller, André; Mensah-Nyagan, Ayikoé G; Schmidt-Mutter, Catherine; Giersch, Anne

    2016-01-01

    Patients with schizophrenia have often been described as insensitive to nociceptive signals, but objective evidence is sparse. We address this question by combining subjective behavioral and objective neurochemical and neurophysiological measures. The present study involved 21 stabilized and mildly symptomatic patients with schizophrenia and 21 control subjects. We applied electrical stimulations below the pain threshold and assessed sensations of pain and unpleasantness with rating scales, and Somatosensory Evoked Potentials (SEPs/EEG). We also measured attention, two neurochemical stress indices (ACTH/cortisol), and subjective VEPs/EEG responses to visual emotional stimuli. Our results revealed that, subjectively, patients' evaluations do not differ from controls. However, the amplitude of EEG evoked potentials was greater in patients than controls as early as 50 ms after electrical stimulations and beyond one second after visual processing of emotional pictures. Such responses could not be linked to the stress induced by the stimulations, since stress hormone levels were stable. Nor was there a difference between patients and controls in respect of attention performance and tactile sensitivity. Taken together, all indices measured in patients in our study were either heightened or equivalent relative to healthy volunteers. PMID:26935652

  20. Neurophysiological responses to unpleasant stimuli (acute electrical stimulations and emotional pictures) are increased in patients with schizophrenia.

    PubMed

    Duval, Céline Z; Goumon, Yannick; Kemmel, Véronique; Kornmeier, Jürgen; Dufour, André; Andlauer, Olivier; Vidailhet, Pierre; Poisbeau, Pierrick; Salvat, Eric; Muller, André; Mensah-Nyagan, Ayikoé G; Schmidt-Mutter, Catherine; Giersch, Anne

    2016-03-03

    Patients with schizophrenia have often been described as insensitive to nociceptive signals, but objective evidence is sparse. We address this question by combining subjective behavioral and objective neurochemical and neurophysiological measures. The present study involved 21 stabilized and mildly symptomatic patients with schizophrenia and 21 control subjects. We applied electrical stimulations below the pain threshold and assessed sensations of pain and unpleasantness with rating scales, and Somatosensory Evoked Potentials (SEPs/EEG). We also measured attention, two neurochemical stress indices (ACTH/cortisol), and subjective VEPs/EEG responses to visual emotional stimuli. Our results revealed that, subjectively, patients' evaluations do not differ from controls. However, the amplitude of EEG evoked potentials was greater in patients than controls as early as 50 ms after electrical stimulations and beyond one second after visual processing of emotional pictures. Such responses could not be linked to the stress induced by the stimulations, since stress hormone levels were stable. Nor was there a difference between patients and controls in respect of attention performance and tactile sensitivity. Taken together, all indices measured in patients in our study were either heightened or equivalent relative to healthy volunteers.

  1. Neurophysiological responses to unpleasant stimuli (acute electrical stimulations and emotional pictures) are increased in patients with schizophrenia

    PubMed Central

    Duval, Céline Z.; Goumon, Yannick; Kemmel, Véronique; Kornmeier, Jürgen; Dufour, André; Andlauer, Olivier; Vidailhet, Pierre; Poisbeau, Pierrick; Salvat, Eric; Muller, André; Mensah-Nyagan, Ayikoé G.; Schmidt-Mutter, Catherine; Giersch, Anne

    2016-01-01

    Patients with schizophrenia have often been described as insensitive to nociceptive signals, but objective evidence is sparse. We address this question by combining subjective behavioral and objective neurochemical and neurophysiological measures. The present study involved 21 stabilized and mildly symptomatic patients with schizophrenia and 21 control subjects. We applied electrical stimulations below the pain threshold and assessed sensations of pain and unpleasantness with rating scales, and Somatosensory Evoked Potentials (SEPs/EEG). We also measured attention, two neurochemical stress indices (ACTH/cortisol), and subjective VEPs/EEG responses to visual emotional stimuli. Our results revealed that, subjectively, patients’ evaluations do not differ from controls. However, the amplitude of EEG evoked potentials was greater in patients than controls as early as 50 ms after electrical stimulations and beyond one second after visual processing of emotional pictures. Such responses could not be linked to the stress induced by the stimulations, since stress hormone levels were stable. Nor was there a difference between patients and controls in respect of attention performance and tactile sensitivity. Taken together, all indices measured in patients in our study were either heightened or equivalent relative to healthy volunteers. PMID:26935652

  2. Local glutamate release in the rat ventral lateral thalamus evoked by high-frequency stimulation

    NASA Astrophysics Data System (ADS)

    Agnesi, Filippo; Blaha, Charles D.; Lin, Jessica; Lee, Kendall H.

    2010-04-01

    Thalamic deep brain stimulation (DBS) is proven therapy for essential tremor, Parkinson's disease and Tourette's syndrome. We tested the hypothesis that high-frequency electrical stimulation results in local thalamic glutamate release. Enzyme-linked glutamate amperometric biosensors were implanted in anesthetized rat thalamus adjacent to the stimulating electrode. Electrical stimulation was delivered to investigate the effect of frequency, pulse width, voltage-controlled or current-controlled stimulation, and charge balancing. Monophasic electrical stimulation-induced glutamate release was linearly dependent on stimulation frequency, intensity and pulse width. Prolonged stimulation evoked glutamate release to a plateau that subsequently decayed back to baseline after stimulation. Glutamate release was less pronounced with voltage-controlled stimulation and not present with charge balanced current-controlled stimulation. Using fixed potential amperometry in combination with a glutamate bioprobe and adjacent microstimulating electrode, the present study has shown that monophasic current-controlled stimulation of the thalamus in the anesthetized rat evoked linear increases in local extracellular glutamate concentrations that were dependent on stimulation duration, frequency, intensity and pulse width. However, the efficacy of monophasic voltage-controlled stimulation, in terms of evoking glutamate release in the thalamus, was substantially lower compared to monophasic current-controlled stimulation and entirely absent with biphasic (charge balanced) current-controlled stimulation. It remains to be determined whether similar glutamate release occurs with human DBS electrodes and similar charge balanced stimulation. As such, the present results indicate the importance of evaluating local neurotransmitter dynamics in studying the mechanism of action of DBS.

  3. Evaluation of intradural stimulation efficiency and selectivity in a computational model of spinal cord stimulation.

    PubMed

    Howell, Bryan; Lad, Shivanand P; Grill, Warren M

    2014-01-01

    Spinal cord stimulation (SCS) is an alternative or adjunct therapy to treat chronic pain, a prevalent and clinically challenging condition. Although SCS has substantial clinical success, the therapy is still prone to failures, including lead breakage, lead migration, and poor pain relief. The goal of this study was to develop a computational model of SCS and use the model to compare activation of neural elements during intradural and extradural electrode placement. We constructed five patient-specific models of SCS. Stimulation thresholds predicted by the model were compared to stimulation thresholds measured intraoperatively, and we used these models to quantify the efficiency and selectivity of intradural and extradural SCS. Intradural placement dramatically increased stimulation efficiency and reduced the power required to stimulate the dorsal columns by more than 90%. Intradural placement also increased selectivity, allowing activation of a greater proportion of dorsal column fibers before spread of activation to dorsal root fibers, as well as more selective activation of individual dermatomes at different lateral deviations from the midline. Further, the results suggest that current electrode designs used for extradural SCS are not optimal for intradural SCS, and a novel azimuthal tripolar design increased stimulation selectivity, even beyond that achieved with an intradural paddle array. Increased stimulation efficiency is expected to increase the battery life of implantable pulse generators, increase the recharge interval of rechargeable implantable pulse generators, and potentially reduce stimulator volume. The greater selectivity of intradural stimulation may improve the success rate of SCS by mitigating the sensitivity of pain relief to malpositioning of the electrode. The outcome of this effort is a better quantitative understanding of how intradural electrode placement can potentially increase the selectivity and efficiency of SCS, which, in turn

  4. High frequency stimulation can block axonal conduction.

    PubMed

    Jensen, Alicia L; Durand, Dominique M

    2009-11-01

    High frequency stimulation (HFS) is used to control abnormal neuronal activity associated with movement, seizure, and psychiatric disorders. Yet, the mechanisms of its therapeutic action are not known. Although experimental results have shown that HFS suppresses somatic activity, other data has suggested that HFS could generate excitation of axons. Moreover it is unclear what effect the stimulation has on tissue surrounding the stimulation electrode. Electrophysiological and computational modeling literature suggests that HFS can drive axons at the stimulus frequency. Therefore, we tested the hypothesis that unlike cell bodies, axons are driven by pulse train HFS. This hypothesis was tested in fibers of the hippocampus both in-vivo and in-vitro. Our results indicate that although electrical stimulation could activate and drive axons at low frequencies (0.5-25 Hz), as the stimulus frequency increased, electrical stimulation failed to continuously excite axonal activity. Fiber tracts were unable to follow extracellular pulse trains above 50 Hz in-vitro and above 125 Hz in-vivo. The number of cycles required for failure was frequency dependent but independent of stimulus amplitude. A novel in-vitro preparation was developed, in which, the alveus was isolated from the remainder of the hippocampus slice. The isolated fiber tract was unable to follow pulse trains above 75 Hz. Reversible conduction block occurred at much higher stimulus amplitudes, with pulse train HFS (>150 Hz) preventing propagation through the site of stimulation. This study shows that pulse train HFS affects axonal activity by: (1) disrupting HFS evoked excitation leading to partial conduction block of activity through the site of HFS; and (2) generating complete conduction block of secondary evoked activity, as HFS amplitude is increased. These results are relevant for the interpretation of the effects of HFS for the control of abnormal neural activity such as epilepsy and Parkinson's disease. PMID

  5. Noninvasive brain stimulation improves language learning.

    PubMed

    Flöel, Agnes; Rösser, Nina; Michka, Olesya; Knecht, Stefan; Breitenstein, Caterina

    2008-08-01

    Anodal transcranial direct current stimulation (tDCS) is a reliable technique to improve motor learning. We here wanted to test its potential to enhance associative verbal learning, a skill crucial for both acquiring new languages in healthy individuals and for language reacquisition after stroke-induced aphasia. We applied tDCS (20 min, 1 mA) over the posterior part of the left peri-sylvian area of 19 young right-handed individuals while subjects acquired a miniature lexicon of 30 novel object names. Every subject participated in one session of anodal tDCS, one session of cathodal tDCS, and one sham session in a randomized and double-blinded design with three parallel versions of the miniature lexicon. Outcome measures were learning speed and learning success at the end of each session, and the transfer to the subjects' native language after the respective stimulation. With anodal stimulation, subjects showed faster and better associative learning as compared to sham stimulation. Mood ratings, reaction times, and response styles were comparable between stimulation conditions. Our results demonstrate that anodal tDCS is a promising technique to enhance language learning in healthy adults and may also have the potential to improve language reacquisition after stroke.

  6. Frequency dependence of behavioral modulation by hippocampal electrical stimulation

    PubMed Central

    La Corte, Giorgio; Wei, Yina; Chernyy, Nick; Gluckman, Bruce J.

    2013-01-01

    Electrical stimulation offers the potential to develop novel strategies for the treatment of refractory medial temporal lobe epilepsy. In particular, direct electrical stimulation of the hippocampus presents the opportunity to modulate pathological dynamics at the ictal focus, although the neuroanatomical substrate of this region renders it susceptible to altering cognition and affective processing as a side effect. We investigated the effects of three electrical stimulation paradigms on separate groups of freely moving rats (sham, 8-Hz and 40-Hz sine-wave stimulation of the ventral/intermediate hippocampus, where 8- and 40-Hz stimulation were chosen to mimic naturally occurring hippocampal oscillations). Animals exhibited attenuated locomotor and exploratory activity upon stimulation at 40 Hz, but not at sham or 8-Hz stimulation. Such behavioral modifications were characterized by a significant reduction in rearing frequency, together with increased freezing behavior. Logistic regression analysis linked the observed changes in animal locomotion to 40-Hz electrical stimulation independently of time-related variables occurring during testing. Spectral analysis, conducted to monitor the electrophysiological profile in the CA1 area of the dorsal hippocampus, showed a significant reduction in peak theta frequency, together with reduced theta power in the 40-Hz vs. the sham stimulation animal group, independent of locomotion speed (theta range: 4–12 Hz). These findings contribute to the development of novel and safe medical protocols by indicating a strategy to constrain or optimize parameters in direct hippocampal electrical stimulation. PMID:24198322

  7. Stimulability: relationships to other characteristics of children's phonological systems.

    PubMed

    Tyler, Ann A; Macrae, Toby

    2010-01-01

    In honour of Miccio's memory, this article revisits the topic of stimulability in children with speech sound disorders (SSD). Eighteen children with SSD, aged 3;6-5;5 (M = 4;8), were tested for their system-wide stimulability, percentage consonants correct (PCC), phonetic inventory size, and oral- and speech-motor skills. Pearson Product Moment Correlations were calculated to determine the nature of relations between stimulability and each of these other variables. Results revealed marked relations between stimulability and PCC and between stimulability and inventory size. Relations between stimulability and both multisyllabic nonsense and real word repetition rates were substantial. Findings suggest that stimulability, as measured for a group of sounds typically challenging for children with SSD, reflects both underlying phonological representations (UPRs) and phonetic imitative skill. The impact of poor stimulability skills in children with severe involvement of SSD and limited phonetic inventories implicates not only the potential difficulty non-stimulable sounds pose at the word level, but the need for increasing stimulability in these children. This, in turn, is a tribute to Miccio's intervention programme and the need for including it in both efficacy and efficiency investigations.

  8. Rotational testing.

    PubMed

    Furman, J M

    2016-01-01

    The natural stimulus for the semicircular canals is rotation of the head, which also might stimulate the otolith organs. Vestibular stimulation usually induces eye movements via the vestibulo-ocular reflex (VOR). The orientation of the subject with respect to the axis of rotation and the orientation of the axis of rotation with respect to gravity together determine which labyrinthine receptors are stimulated for particular motion trajectories. Rotational testing usually includes the measurement of eye movements via a video system but might use a subject's perception of motion. The most common types of rotational testing are whole-body computer-controlled sinusoidal or trapezoidal stimuli during earth-vertical axis rotation (EVAR), which stimulates primarily the horizontal semicircular canals bilaterally. Recently, manual impulsive rotations, known as head impulse testing (HIT), have been developed to assess individual horizontal semicircular canals. Most types of rotational stimuli are not used routinely in the clinical setting but may be used in selected research environments. This chapter will discuss clinically relevant rotational stimuli and several types of rotational testing that are used primarily in research settings. PMID:27638070

  9. Stimulated parametric emission microscopy

    NASA Astrophysics Data System (ADS)

    Isobe, Keisuke; Kataoka, Shogo; Murase, Rena; Watanabe, Wataru; Higashi, Tsunehito; Kawakami, Shigeki; Matsunaga, Sachihiro; Fukui, Kiichi; Itoh, Kazuyoshi

    2006-01-01

    We propose a novel microscopy technique based on the four-wave mixing (FWM) process that is enhanced by two-photon electronic resonance induced by a pump pulse along with stimulated emission induced by a dump pulse. A Ti:sapphire laser and an optical parametric oscillator are used as light sources for the pump and dump pulses, respectively. We demonstrate that our proposed FWM technique can be used to obtain a one-dimensional image of ethanol-thinned Coumarin 120 solution sandwiched between a hole-slide glass and a cover slip, and a two-dimensional image of a leaf of Camellia sinensis.

  10. Dorsal column stimulator applications

    PubMed Central

    Yampolsky, Claudio; Hem, Santiago; Bendersky, Damián

    2012-01-01

    Background: Spinal cord stimulation (SCS) has been used to treat neuropathic pain since 1967. Following that, technological progress, among other advances, helped SCS become an effective tool to reduce pain. Methods: This article is a non-systematic review of the mechanism of action, indications, results, programming parameters, complications, and cost-effectiveness of SCS. Results: In spite of the existence of several studies that try to prove the mechanism of action of SCS, it still remains unknown. The mechanism of action of SCS would be based on the antidromic activation of the dorsal column fibers, which activate the inhibitory interneurons within the dorsal horn. At present, the indications of SCS are being revised constantly, while new applications are being proposed and researched worldwide. Failed back surgery syndrome (FBSS) is the most common indication for SCS, whereas, the complex regional pain syndrome (CRPS) is the second one. Also, this technique is useful in patients with refractory angina and critical limb ischemia, in whom surgical or endovascular treatment cannot be performed. Further indications may be phantom limb pain, chronic intractable pain located in the head, face, neck, or upper extremities, spinal lumbar stenosis in patients who are not surgical candidates, and others. Conclusion: Spinal cord stimulation is a useful tool for neuromodulation, if an accurate patient selection is carried out prior, which should include a trial period. Undoubtedly, this proper selection and a better knowledge of its underlying mechanisms of action, will allow this cutting edge technique to be more acceptable among pain physicians. PMID:23230533

  11. Central nervous system stimulants.

    PubMed

    George, A J

    2000-03-01

    Three major types of CNS stimulant are currently abused in sport: amphetamine, cocaine and caffeine. Each drug type has its own characteristic mechanism of action on CNS neurones and their associated receptors and nerve terminals. Amphetamine is widely abused in sports requiring intense anaerobic exercise where it prolongs the tolerance to anaerobic metabolism. It is addictive, and chronic abuse causes marked behavioural change and sometimes psychosis. Major sports abusing amphetamine are cycling, American football, ice-hockey and baseball. Cocaine increases tolerance to intense exercise, yet most of its chronic effects on energy metabolism are negative. Its greatest effects seem to be as a central stimulant and the enhancement of short-term anaerobic exercise. It is highly addictive and can cause cerebral and cardiovascular fatalities. Caffeine enhances fatty acid metabolism leading to glucose conservation, which appears to benefit long-distance endurance events such as skiing. Caffeine is also addictive, and chronic abuse can lead to cardiac damage. Social abuse of each of the three drugs is often difficult to distinguish from their abuse in sport.

  12. Klamath Falls: High-Power Acoustic Well Stimulation Technology

    SciTech Connect

    Black, Brian

    2006-07-24

    Acoustic well stimulation (AWS) technology uses high-power sonic waves from specific frequency spectra in an attempt to stimulate production in a damaged or low-production wellbore. AWS technology is one of the most promising technologies in the oil and gas industry, but it has proven difficult for the industry to develop an effective downhole prototype. This collaboration between Klamath Falls Inc. and the Rocky Mountain Oilfield Testing Center (RMOTC) included a series of tests using high-power ultrasonic tools to stimulate oil and gas production. Phase I testing was designed and implemented to verify tool functionality, power requirements, and capacity of high-power AWS tools. The purpose of Phase II testing was to validate the production response of wells with marginal production rates to AWS stimulation and to capture and identify any changes in the downhole environment after tool deployment. This final report presents methodology and results.

  13. A linearized current stimulator for deep brain stimulation.

    PubMed

    Shen, Ding-Lan; Chu, Yu-Jung

    2010-01-01

    This paper develops the front end of the stimulator which is applied in the implantable deep brain stimulation (DBS) for the therapy of Parkinson's disease. This stimulator adopts the low power switched-capacitor DAC accompanying with voltage-to-current transconductance amplifiers to obtain the adjustable output currents. The proposed distortion cancellation technique improves the linearity of the current stimulator. Multiple transconductance amplifiers sharing a single DAC save the circuit area. The biphasic stimulation waveform is generated from the bridge switching technique and the programmable pulse. This stimulation circuit provides the 0 approximately 165 microA current for a typical loading of 10 kΩ, 8 approximately 120 micros pulse width, and 126 approximately 244 Hz frequencies with a 0.35 microm CMOS technology at 3.3 V supply voltage. PMID:21096724

  14. Engagement Sensitive Visual Stimulation.

    PubMed

    Kumar, Deepesh; Dutta, Anirban; Das, Abhijit; Lahiri, Uttama

    2016-06-13

    Stroke is one of leading cause of death and disability worldwide. Early detection during golden hour and treatment of individual neurological dysfunction in stroke using easy-to-access biomarkers based on a simple-to-use, cost-effective, clinically-valid screening tool can bring a paradigm shift in healthcare, both urban and rural. In our research we have designed a quantitative automatic home-based oculomotor assessment tool that can play an important complementary role in prognosis of neurological disorders like stroke for the neurologist. Once the patient has been screened for stroke, the next step is to design proper rehabilitation platform to alleviate the disability. In addition to the screening platform, in our research, we work in designing virtual reality based rehabilitation exercise platform that has the potential to deliver visual stimulation and in turn contribute to improving one's performance. PMID:27478569

  15. Stimulated radiative laser cooling

    NASA Astrophysics Data System (ADS)

    Muys, P.

    2008-04-01

    Building a refrigerator based on the conversion of heat into optical energy is an ongoing engineering challenge. Under well-defined conditions, spontaneous anti-Stokes fluorescence of a dopant material in a host matrix is capable of lowering the host temperature. The fluorescence is conveying away a part of the thermal energy stored in the vibrational oscillations of the host lattice. In particular, applying this principle to the cooling of (solid-state) lasers opens up many potential device applications, especially in the domain of high-power lasers. In this paper, an alternative optical cooling scheme is outlined, leading to the radiative cooling of solid-state lasers. It is based on converting the thermal energy stored in the host into optical energy by means of a stimulated nonlinear process, rather than a spontaneous process. This should lead to better cooling efficiencies and a higher potential of applying the principle for device applications.

  16. Stimulated rotational Raman scattering

    NASA Astrophysics Data System (ADS)

    Parazzoli, C. G.; Rafanelli, G. L.; Capps, D. M.; Drutman, C.

    1989-03-01

    The effect of Stimulated Rotational Raman Scattering (SRRS) processes on high energy laser directed energy weapon systems was studied. The program had 3 main objectives; achieving an accurate description of the physical processes involved in SRRS; developing a numerical algorithm to confidently evaluate SRRS-induced losses in the propagation of high energy laser beams in the uplink and downlink segments of the optical trains of various strategic defense system scenarios; and discovering possible methods to eliminate, or at least reduce, the deleterious effects of SRRS on the energy deposition on target. The following topics are discussed: the motivation for the accomplishments of the DOE program; the Semiclassical Theory of Non-Resonant SRRS for Diatomic Homonuclear Molecules; and then the following appendices; Calculation of the Dipole Transition Reduced Matrix Element, Guided Tour of Hughes SRRS Code, Running the Hughes SRRS Code, and Hughes SRRS Code Listing.

  17. Myeloperoxidase Stimulates Neutrophil Degranulation.

    PubMed

    Grigorieva, D V; Gorudko, I V; Sokolov, A V; Kostevich, V A; Vasilyev, V B; Cherenkevich, S N; Panasenko, O M

    2016-08-01

    Myeloperoxidase, heme enzyme of azurophilic granules in neutrophils, is released into the extracellular space in the inflammation foci. In neutrophils, it stimulates a dose-dependent release of lactoferrin (a protein of specific granules), lysozyme (a protein of specific and azurophilic granules), and elastase (a protein of azurophilic granules). 4-Aminobenzoic acid hydrazide, a potent inhibitor of peroxidase activity of myeloperoxidase, produced no effect on neutrophil degranulation. Using signal transduction inhibitors (genistein, methoxyverapamil, wortmannin, and NiCl2), we demonstrated that myeloperoxidase-induced degranulation of neutrophils resulted from enzyme interaction with the plasma membrane and depends on activation of tyrosine kinases, phosphatidylinositol 3-kinases (PI3K), and calcium signaling. Myeloperoxidase modified by oxidative/halogenation stress (chlorinated and monomeric forms of the enzyme) lost the potency to activate neutrophil degranulation. PMID:27597056

  18. Engagement Sensitive Visual Stimulation

    PubMed Central

    Kumar, Deepesh; Dutta, Anirban; Das, Abhijit; Lahiri, Uttama

    2016-01-01

    Stroke is one of leading cause of death and disability worldwide. Early detection during golden hour and treatment of individual neurological dysfunction in stroke using easy-to-access biomarkers based on a simple-to-use, cost-effective, clinically-valid screening tool can bring a paradigm shift in healthcare, both urban and rural. In our research we have designed a quantitative automatic home-based oculomotor assessment tool that can play an important complementary role in prognosis of neurological disorders like stroke for the neurologist. Once the patient has been screened for stroke, the next step is to design proper rehabilitation platform to alleviate the disability. In addition to the screening platform, in our research, we work in designing virtual reality based rehabilitation exercise platform that has the potential to deliver visual stimulation and in turn contribute to improving one’s performance. PMID:27478569

  19. Electrochemical corrosion of STS304 acupuncture needles by electrical stimulation.

    PubMed

    Hwang, Hye Suk; Yang, Eun Jin; Ryu, Yeon Hee; Lee, Myeong Soo; Choi, Sun-Mi

    2010-06-01

    We present the first investigation of electrical corrosion in acupuncture needles after electrical stimulation. Using scanning electron microscopy, we observed the occurrence of electrochemical corrosion on the surface of stainless steel 304 acupuncture needles after electrical stimulation in the tibial muscles of rats. Biphasic pulse electrical stimuli with 10-Hz frequency, 1-mA intensity and 1-ms pulse width were applied to the needles. The terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method labels fragmented DNA. Positive staining using this test indicates apoptotic cells in electrically stimulated tissues. The risk of electrical corrosion was found to be less in bipolar, short-duration, low-current or voltage and short-period stimulation than in monopolar, long-duration, high-current or voltage and long-period stimulation. Evaluation with a scanning electron microscope revealed that electrical stimulation can increase the electrical corrosion of stainless steel 304 acupuncture needles. In biocompatibility studies of stainless steel 304 acupuncture needles for electrical stimulation, TUNEL-positive cells were detected in the tibial muscle within 5 days after electrical stimulation. The results of this study demonstrate that the corrosion products of stainless steel 304 acupuncture needles might affect the post-electrical stimulation tissue response. PMID:20633521

  20. Spiral scan peripheral nerve stimulation.

    PubMed

    King, K F; Schaefer, D J

    2000-07-01

    Time-varying magnetic fields induce electric fields that can cause physiological stimulation. Stimulation has been empirically characterized as a function of dB/dt and duration based on experiments using trapezoidal and sinusoidal gradient waveforms with constant ramp time, amplitude, and direction. For two-dimensional (2D) spiral scans, the readout gradient waveforms are frequency- and amplitude-modulated sinusoids on two orthogonal axes in quadrature. The readout gradient waveform therefore rotates with amplitude and angular velocity that are generally not constant. It does not automatically follow that spiral stimulation thresholds can be predicted using available stimulation models. We scanned 18 normal volunteers with a 2D spiral scan and measured global thresholds for axial, sagittal, and coronal planes. We concluded that the stimulation model evaluated accurately predicts slew rate-limited spiral mean stimulation thresholds, if the effective ramp time is chosen to be the half-period at the end of the spiral readout.

  1. Test Takers' Writing Activities during the "TOEFL iBT"® Writing Tasks: A Stimulated Recall Study. "TOEFL iBT"® Research Report. TOEFL iBT-25. ETS Research Report No. RR-15-04

    ERIC Educational Resources Information Center

    Barkaoui, Khaled

    2015-01-01

    This study aimed to describe the writing activities that test takers engage in when responding to the writing tasks in the "TOEFL iBT"[superscript R] test and to examine the effects of task type and test-taker English language proficiency (ELP) and keyboarding skills on the frequency and distribution of these activities. Each of 22 test…

  2. Hydromechanical stimulation of bioluminescent plankton.

    PubMed

    Blaser, Stefan; Kurisu, Futoshi; Satoh, Hiroyasu; Mino, Takashi

    2002-01-01

    The response of the bioluminescent dinoflagellate Pyrocystis fusiformis was investigated for different hydraulic conditions ('hydromechanical stimulation'). Pipe flow and oscillating shear produced luminescence, whereas changes in hydrostatic pressure were not stimulating. More intense fluid motion led to higher intensity, mainly due to a higher probability of cell response. The organism was also able to emit light in a glucose-salt mixture. The experiments suggest that the cells are effectively stimulated if the flow conditions change in time.

  3. Optically stimulated differential impedance spectroscopy

    DOEpatents

    Maxey, Lonnie C; Parks, II, James E; Lewis, Sr., Samuel A; Partridge, Jr., William P

    2014-02-18

    Methods and apparatuses for evaluating a material are described. Embodiments typically involve use of an impedance measurement sensor to measure the impedance of a sample of the material under at least two different states of illumination. The states of illumination may include (a) substantially no optical stimulation, (b) substantial optical stimulation, (c) optical stimulation at a first wavelength of light, (d) optical stimulation at a second wavelength of light, (e) a first level of light intensity, and (f) a second level of light intensity. Typically a difference in impedance between the impedance of the sample at the two states of illumination is measured to determine a characteristic of the material.

  4. Electrical stimulation: a societal perspective.

    PubMed

    Gater, D R; McDowell, S M; Abbas, J J

    2000-01-01

    Societal perspective on functional electrical stimulation is colored by media influence, popular thought, and political climate as much as by the science that supports it. The purpose of this article is to examine how these influences facilitate or inhibit the application of electrical stimulation in today's world and to describe the challenges facing the use of electrical stimulation in the future. Emphasis will be placed on perceived need, cost, and available resources and how these factors must be addressed to utilize functional electrical stimulation successfully in society.

  5. Mechanical stimulation enhances endothelin-1 hyperalgesia.

    PubMed

    Joseph, E K; Gear, R W; Levine, J D

    2011-03-31

    When comparing a cumulative dose-response curve for endothelin-1 (ET-1)-induced mechanical hyperalgesia to the effect of individual doses (1 ng, 10 ng, 100 ng, and 1 μg) administered in separate groups of rats, a marked difference was observed in the peak magnitude of hyperalgesia. Hyperalgesia was measured as decrease in the threshold for mechanically-induced withdrawal of the hind paw. The cumulative dosing protocol produced markedly greater maximum hyperalgesia. To determine whether this was due to the cumulative dosing protocol or to the repeated exposure to the mechanical test stimulus, we evaluated the impact of repeated testing on ET-1-induced mechanical hyperalgesia. While ET-1-induced mechanical hyperalgesia was dose- and time-dependent, repeated testing of nociceptive threshold, at 5 min intervals, following a single dose of ET-1, produced further decrease in nociceptive threshold. This mechanical stimulation-induced enhancement of ET-1 hyperalgesia lasted only 3-4 h, while the hyperalgesia lasted in excess of 5 days. The stimulation-enhanced hyperalgesia also occurred after a second injection of ET-1, administered 24 h after the initial dose. That this phenomenon is unique to ET-1 is suggested by the observation that while five additional, direct-acting hyperalgesic agents-prostaglandin E2 (PGE2), nerve growth factor (NGF), glia-derived neurotrophic factor (GDNF), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNFα)-induced robust mechanical hyperalgesia, none produced mechanical stimulation-enhanced hyperalgesia.

  6. Electrical stimulation vs. pulsed and continuous-wave optical stimulation of the rat prostate cavernous nerves, in vivo

    NASA Astrophysics Data System (ADS)

    Perkins, William C.; Lagoda, Gwen A.; Burnett, Arthur; Fried, Nathaniel M.

    2015-07-01

    Identification and preservation of the cavernous nerves (CNs) during prostate cancer surgery is critical for post-operative sexual function. Electrical nerve stimulation (ENS) mapping has previously been tested as an intraoperative tool for CN identification, but was found to be unreliable. ENS is limited by the need for electrode-tissue contact, poor spatial precision from electrical current spreading, and stimulation artifacts interfering with detection. Alternatively, optical nerve stimulation (ONS) provides noncontact stimulation, improved spatial selectivity, and elimination of stimulation artifacts. This study compares ENS to pulsed/CW ONS to explore the ONS mechanism. A total of eighty stimulations were performed in 5 rats, in vivo. ENS (4 V, 5 ms, 10 Hz) was compared to ONS using a pulsed diode laser nerve stimulator (1873 nm, 5 ms, 10 Hz) or CW diode laser nerve stimulator (1455 nm). Intracavernous pressure (ICP) response and nerve compound action potentials (nCAPs) were measured. All three stimulation modes (ENS, ONS-CW, ONS-P) produced comparable ICP magnitudes. However, ENS demonstrated more rapid ICP response times and well defined nCAPs compared to unmeasurable nCAPs for ONS. Further experiments measuring single action potentials during ENS and ONS are warranted to further understand differences in the ENS and ONS mechanisms.

  7. Stimulation of the hypothalamo-pituitary-adrenal axis in the rat by the type 4 phosphodiesterase (PDE-4) inhibitor, denbufylline.

    PubMed Central

    Hadley, A. J.; Kumari, M.; Cover, P. O.; Osborne, J.; Poyser, R.; Flack, J. D.; Buckingham, J. C.

    1996-01-01

    1. Preliminary studies in our laboratories showed that the synthetic xanthine analogue denbufylline, a selective type 4 phosphodiesterase (PDE-4) inhibitor, is a potent activator of the hypothalamo-pituitary-adrenal (HPA) axis when given orally to adult male rats. This paper describes the results of experiments in which well established in vivo and in vitro models were used to (a) examine further the effects of denbufylline on HPA function and (b) identify the site and mode of action of the drug within the axis. 2. In vivo, administration of denbufylline (0.1-2.5 mg kg-1, i.p.) produced a significant increase in the serum corticosterone concentration; maximal responses were attained at a dose of 1.0 mg kg-1 (P < 0.01 vs. vehicle control, Scheffe's test). However, when denbufylline was administered by intracerebroventricular injection (0.05-1 micrograms kg-1) it failed to influence significantly the serum corticosterone concentration (P > 0.05 vs. vehicle control, Scheffe's test). The adrenocortical responses to peripheral injections of denbufylline (1 mg kg-1, i.p.) were reduced in rats in which the secretion of endogenous corticotrophin releasing factors (CRFs) from the hypothalamus was blocked pharmacologically (P < 0.01 vs. controls, Scheffe's test). However, denbufylline (0.1 mg kg-1, i.p.) potentiated the significant (P < 0.01) increases in serum corticosterone concentration provoked in "CRF blocked rats' by hypothalamic extract (5 hypothalamic extracts kg-1, i.v.) although it failed to influence (P > 0.05) the relatively moderate increases in corticosterone secretion evoked by CRH-41 (2 mg kg-1, i.v.). 3. In vitro, denbufylline (0.01-1 mM) evoked small but significant (P < 0.05) increases in the release of ACTH from rat anterior pituitary segments; furthermore, at these and lower concentrations (0.01 microM-1 mM), it potentiated the adrenocorticotrophic responses to sub-maximal concentrations of hypothalamic extract (P < 0.01) and forskolin (0.1 mM, P < 0

  8. Reinforcing brain stimulation in competition with water reward and shock avoidance.

    PubMed

    VALENSTEIN, E S; BEER, B

    1962-09-28

    Employing response rate as the index of reinforcing strength in self-stimulation experiments is questioned. With water reward or shock avoidance placed in competition with brain stimulation, self-stimulation rate does not reflect relative reinforcement value. The results agree with preference tests which show that, for a given electrode site, stimulus intensity, not rate, is directly related to reward strength.

  9. Peripheral neural activity recording and stimulation system.

    PubMed

    Loi, D; Carboni, C; Angius, G; Angotzi, G N; Barbaro, M; Raffo, L; Raspopovic, S; Navarro, X

    2011-08-01

    This paper presents a portable, embedded, microcontroller-based system for bidirectional communication (recording and stimulation) between an electrode, implanted in the peripheral nervous system, and a host computer. The device is able to record and digitize spontaneous and/or evoked neural activities and store them in data files on a PC. In addition, the system has the capability of providing electrical stimulation of peripheral nerves, injecting biphasic current pulses with programmable duration, intensity, and frequency. The recording system provides a highly selective band-pass filter from 800 Hz to 3 kHz, with a gain of 56 dB. The amplification range can be further extended to 96 dB with a variable gain amplifier. The proposed acquisition/stimulation circuitry has been successfully tested through in vivo measurements, implanting a tf-LIFE electrode in the sciatic nerve of a rat. Once implanted, the device showed an input referred noise of 0.83 μVrms, was capable of recording signals below 10 μ V, and generated muscle responses to injected stimuli. The results demonstrate the capability of processing and transmitting neural signals with very low distortion and with a power consumption lower than 1 W. A graphic, user-friendly interface has been developed to facilitate the configuration of the entire system, providing the possibility to activate stimulation and monitor recordings in real time.

  10. Aromatase inhibitors in stimulated IVF cycles

    PubMed Central

    2011-01-01

    Aromatase inhibitors have been introduced as a new treatment modality that could challenge clomiphene citrate as an ovulation induction regiment in patients with PCOS. Although several randomized trials have been conducted regarding their use as ovulation induction agents, only few trials are available regarding their efficacy in IVF stimulated cycles. Current available evidence support that letrozole may have a promising role in stimulated IVF cycles, either when administered during the follicular phase for ovarian stimulation. Especially for women with poor ovarian response, letrozole appears to have the potential to increase clinical pregnancy rates when combined with gonadotropins, whereas at the same time reduces the total gonadotropin dose required for ovarian stimulation. However, given that in all of the trials letrozole has been administered in GnRH antagonist cycles, it is intriguing to test in the future how it may perform when used in GnRH agonist cycles. Finally administration of letrozole during luteal phase in IVF cycles offers another treatment modality for patients at high risk for OHSS taking into account that it drastically reduces estradiol levels PMID:21693033

  11. Elevations in plasmatic titers of corticosterone and aldosterone, in the absence of changes in ACTH, testosterone, or glial fibrillary acidic protein, 72 h following D,L-fenfluramine or D-fenfluramine administration to rats.

    PubMed

    Williams, M T; Morford, L L; McCrea, A E; Inman-Wood, S L; Vorhees, C V

    2001-01-01

    Studies in both humans and animals demonstrate that D,L- and D-fenfluramine (D,L-FEN and D-FEN, respectively) can activate the hypothalamic-pituitary-adrenal axis following an acute dose. No data exist showing a prolonged effect of either drug, although two studies have hinted at increased adrenal activity. There are also considerable differences in the literature pertaining to the neurotoxic effects of D,L- and D-FEN. Some possible explanations for these differences include: activation of different neurotransmitter systems, the temperature at which the animals were maintained during exposure, or the substance sampled in each study. We investigated the effects of either D,L-FEN or D-FEN on pituitary, adrenal, and gonadal hormones 72 h after drug exposure. Furthermore, using a dosing regimen adapted from studies on methamphetamine (e.g., four times every 2 h in a single day) known to produce elevations in glial fibrillary acidic protein (GFAP) under hyperthermic conditions, we examined the effects of D- and D,L-FEN (15 mg/kg, four times) on GFAP content when the animals were dosed at ambient temperatures of 21 or 32 degrees C. Approximately fivefold increases of corticosterone and threefold increases of aldosterone were found 72 h later under resting conditions following both D- and D,L-FEN. Nonetheless, when animals were dosed with D-FEN at 32 degrees C, no significant elevation in corticosterone was detected. No effect was observed for ACTH, testosterone, or GFAP following D- or D,L-FEN treatment. These data suggest that: (1) FEN treatment causes prolonged elevations in adrenal cortical hormones; (2) FEN-treated animals displayed hormonal characteristics similar to animals undergoing a chronic stressor as suggested by no difference in ACTH titers; (3) D,L-FEN treatment or D-FEN treatment (as reported previously) is not similar to other substituted amphetamines in that it does not increase GFAP, even under hyperthermic conditions.

  12. Atomic oxygen stimulated outgassing

    NASA Technical Reports Server (NTRS)

    Linton, Roger C.; Reynolds, John M.

    1991-01-01

    The passive Long Duration Exposure Facility (LDEF) Experiment A0034, Atomic Oxygen Simulated Outgassing, consisted of two identical one-sixth tray modules, exposing selected thermal control coatings to atomic oxygen and the combined space environment on the leading edge and, for reference, to the relative wake environment on the trailing edge. Optical mirrors were included adjacent to the thermal coatings for deposition of outgassing products. Ultraviolet grade windows and metal covers were provided for additional assessment of the effects of the various environmental factors. Preliminary results indicate that orbital atomic oxygen is both a degrading and a optically restorative factor in the thermo-optical properties of selected thermal coatings. There is evidence of more severe optical degradation on collector mirrors adjacent to coatings that were exposed to the RAM-impinging atomic oxygen. This evidence of atomic oxygen stimulated outgassing is discussed in relation to alternative factors that could affect degradation. The general effects of the space environment on the experiment hardware as well as the specimens are discussed.

  13. EOR by stimulated microflora

    SciTech Connect

    Svarovskaya, L.I.; Altunina, L.K.; Rozhenkova, Z.A.; Bulavin, V.D.

    1995-12-31

    A combined microbiological and physico-chemical method for EOR has been developed for flooded West Siberia oil fields with formation temperature of 45{degrees}-95{degrees}C (318-365K). Formation water includes rich and various biocenoses numbering up to 2 x 10{sup 7} cells per ml. Representatives of genera, i.e, Pseudomonas, Bacillus, Actinomyces, Micrococcus, Mycobacterium, Sarcina, etc. were found to be the most widely distributed microorganisms. The method is based on injection of systems exhibiting high oil displacing capacity and at the same time being an additional nitrous nutrient for endemic populations of microorganisms. Their injection into formation water favors biomass growth by 4-6 orders and promotes syntheses of biosurfactants, biopolymers, acids, etc., and gaseous products. The features of residual oil displacement have been studied on laboratory models using a combined microbiological and physico-chemical method. A curve for the yield of residual oil is presented by two peaks. The first peak is stipulated by the washing action of oil displacement system, and the second one by the effect of metabolites produced at stimulation of biogenic processes. Oil displacement index increases by 15%-30%.

  14. Corticotropin-releasing hormone directly stimulates cortisol and the cortisol biosynthetic pathway in human fetal adrenal cells.

    PubMed

    Sirianni, Rosa; Rehman, Khurram S; Carr, Bruce R; Parker, C Richard; Rainey, William E

    2005-01-01

    Near term the human fetal adrenals (HFAs) initiate production of cortisol, which promotes organ maturation and acts to increase placental CRH biosynthesis. The objective of the present study was to determine whether CRH directly stimulates both cortisol production and expression of the steroidogenic enzymes in HFA-definitive zone cells. CRH stimulated the production of cortisol in a time- and dose-dependent manner, with an effective concentration of as low as 0.01 nm. In real-time RT-PCR experiments, CRH treatment increased the mRNA levels of steroidogenic acute regulatory protein and each of the enzymes needed to produce cortisol. CRH induced 3beta-hydroxysteroid dehydrogenase type II (HSD3B2) by 34-fold, 21-hydroxylase (CYP21) by 55-fold, and 11beta-hydroxylase by 41-fold. Induction of steroidogenic acute regulatory protein, cholesterol side chain cleavage (CYP11A), and 17alpha-hydroxylase (CYP17) mRNA by CRH was 6-, 4-, and 6-fold, respectively. We also demonstrated that submaximal concentrations of CRH (30 pm) and ACTH (30 pm) that are seen in fetal circulation were additive on cortisol biosynthesis and 3beta-hydroxysteroid dehydrogenase type II mRNA induction. We suggest that CRH may play an important role in the late gestational rise in cortisol secretion from the HFAs, which may serve to augment placental CRH production and therefore participate in the endocrine cascade that is involved in fetal organ maturation and potentially in the timing of human parturition.

  15. Subliminal Stimulation: Hoax or Reality?

    ERIC Educational Resources Information Center

    Trank, Douglas M.

    Subliminal stimulation is defined as that which is perceived by an individual below the threshold of awareness or cognizance. This article traces the history of research in subliminal stimulation to illustrate that under certain circumstances and conditions, this behavioral phenomenon does occur. Although subliminal stimuli do affect human…

  16. Stimulating Language: Insights from TMS

    ERIC Educational Resources Information Center

    Devlin, Joseph T.; Watkins, Kate E.

    2007-01-01

    Fifteen years ago, Pascual-Leone and colleagues used transcranial magnetic stimulation (TMS) to investigate speech production in pre-surgical epilepsy patients and in doing so, introduced a novel tool into language research. TMS can be used to non-invasively stimulate a specific cortical region and transiently disrupt information processing. These…

  17. Lipopolysaccharide (LPS) stimulation of fungal secondary metabolism

    PubMed Central

    Khalil, Zeinab G.; Kalansuriya, Pabasara; Capon, Robert J.

    2014-01-01

    We report on a preliminary investigation of the use the Gram-negative bacterial cell wall constituent lipopolysaccharide (LPS) as a natural chemical cue to stimulate and alter the expression of fungal secondary metabolism. Integrated high-throughput micro-cultivation and micro-analysis methods determined that 6 of 40 (15%) of fungi tested responded to an optimal exposure to LPS (0.6 ng/mL) by activating, enhancing or accelerating secondary metabolite production. To explore the possible mechanisms behind this effect, we employed light and fluorescent microscopy in conjunction with a nitric oxide (NO)-sensitive fluorescent dye and an NO scavenger to provide evidence that LPS stimulation of fungal secondary metabolism coincided with LPS activation of NO. Several case studies demonstrated that LPS stimulation can be scaled from single microplate well (1.5 mL) to preparative (>400 mL) scale cultures. For example, LPS treatment of Penicillium sp. (ACM-4616) enhanced pseurotin A and activated pseurotin A1 and pseurotin A2 biosynthesis, whereas LPS treatment of Aspergillus sp. (CMB-M81F) substantially accelerated and enhanced the biosynthesis of shornephine A and a series of biosynthetically related ardeemins and activated production of neoasterriquinone. As an indication of broader potential, we provide evidence that cultures of Penicillium sp. (CMB-TF0411), Aspergillus niger (ACM-4993F), Rhizopus oryzae (ACM-165F) and Thanatephorus cucumeris (ACM-194F) were responsive to LPS stimulation, the latter two examples being particular noteworthy as neither are known to produce secondary metabolites. Our results encourage the view that LPS stimulation can be used as a valuable tool to expand the molecular discovery potential of fungal strains that either have been exhaustively studied by or are unresponsive to traditional culture methodology. PMID:25379339

  18. Tissue damage thresholds during therapeutic electrical stimulation

    NASA Astrophysics Data System (ADS)

    Cogan, Stuart F.; Ludwig, Kip A.; Welle, Cristin G.; Takmakov, Pavel

    2016-04-01

    Objective. Recent initiatives in bioelectronic modulation of the nervous system by the NIH (SPARC), DARPA (ElectRx, SUBNETS) and the GlaxoSmithKline Bioelectronic Medicines effort are ushering in a new era of therapeutic electrical stimulation. These novel therapies are prompting a re-evaluation of established electrical thresholds for stimulation-induced tissue damage. Approach. In this review, we explore what is known and unknown in published literature regarding tissue damage from electrical stimulation. Main results. For macroelectrodes, the potential for tissue damage is often assessed by comparing the intensity of stimulation, characterized by the charge density and charge per phase of a stimulus pulse, with a damage threshold identified through histological evidence from in vivo experiments as described by the Shannon equation. While the Shannon equation has proved useful in assessing the likely occurrence of tissue damage, the analysis is limited by the experimental parameters of the original studies. Tissue damage is influenced by factors not explicitly incorporated into the Shannon equation, including pulse frequency, duty cycle, current density, and electrode size. Microelectrodes in particular do not follow the charge per phase and charge density co-dependence reflected in the Shannon equation. The relevance of these factors to tissue damage is framed in the context of available reports from modeling and in vivo studies. Significance. It is apparent that emerging applications, especially with microelectrodes, will require clinical charge densities that exceed traditional damage thresholds. Experimental data show that stimulation at higher charge densities can be achieved without causing tissue damage, suggesting that safety parameters for microelectrodes might be distinct from those defined for macroelectrodes. However, these increased charge densities may need to be justified by bench, non-clinical or clinical testing to provide evidence of device

  19. Spatially Patterned Electrical Stimulation to Enhance Resolution of Retinal Prostheses

    PubMed Central

    Hottowy, Paweł; Mathieson, Keith; Gunning, Deborah E.; Dąbrowski, Władysław; Litke, Alan M.; Chichilnisky, E. J.

    2014-01-01

    Retinal prostheses electrically stimulate neurons to produce artificial vision in people blinded by photoreceptor degenerative diseases. The limited spatial resolution of current devices results in indiscriminate stimulation of interleaved cells of different types, precluding veridical reproduction of natural activity patterns in the retinal output. Here we investigate the use of spatial patterns of current injection to increase the spatial resolution of stimulation, using high-density multielectrode recording and stimulation of identified ganglion cells in isolated macaque retina. As previously shown, current passed through a single electrode typically induced a single retinal ganglion cell spike with submillisecond timing precision. Current passed simultaneously through pairs of neighboring electrodes modified the probability of activation relative to injection through a single electrode. This modification could be accurately summarized by a piecewise linear model of current summation, consistent with a simple biophysical model based on multiple sites of activation. The generalizability of the piecewise linear model was tested by using the measured responses to stimulation with two electrodes to predict responses to stimulation with three electrodes. Finally, the model provided an accurate prediction of which among a set of spatial stimulation patterns maximized selective activation of a cell while minimizing activation of a neighboring cell. The results demonstrate that tailored multielectrode stimulation patterns based on a piecewise linear model may be useful in increasing the spatial resolution of retinal prostheses. PMID:24695706

  20. Stimulation of the human auditory nerve with optical radiation

    NASA Astrophysics Data System (ADS)

    Fishman, Andrew; Winkler, Piotr; Mierzwinski, Jozef; Beuth, Wojciech; Izzo Matic, Agnella; Siedlecki, Zygmunt; Teudt, Ingo; Maier, Hannes; Richter, Claus-Peter

    2009-02-01

    A novel, spatially selective method to stimulate cranial nerves has been proposed: contact free stimulation with optical radiation. The radiation source is an infrared pulsed laser. The Case Report is the first report ever that shows that optical stimulation of the auditory nerve is possible in the human. The ethical approach to conduct any measurements or tests in humans requires efficacy and safety studies in animals, which have been conducted in gerbils. This report represents the first step in a translational research project to initiate a paradigm shift in neural interfaces. A patient was selected who required surgical removal of a large meningioma angiomatum WHO I by a planned transcochlear approach. Prior to cochlear ablation by drilling and subsequent tumor resection, the cochlear nerve was stimulated with a pulsed infrared laser at low radiation energies. Stimulation with optical radiation evoked compound action potentials from the human auditory nerve. Stimulation of the auditory nerve with infrared laser pulses is possible in the human inner ear. The finding is an important step for translating results from animal experiments to human and furthers the development of a novel interface that uses optical radiation to stimulate neurons. Additional measurements are required to optimize the stimulation parameters.

  1. Deep brain stimulation affects conditioned and unconditioned anxiety in different brain areas.

    PubMed

    van Dijk, A; Klanker, M; van Oorschot, N; Post, R; Hamelink, R; Feenstra, M G P; Denys, D

    2013-01-01

    Deep brain stimulation (DBS) of the nucleus accumbens (NAc) has proven to be an effective treatment for therapy refractory obsessive-compulsive disorder. Clinical observations show that anxiety symptoms decrease rapidly following DBS. As in clinical studies different regions are targeted, it is of principal interest to understand which brain area is responsible for the anxiolytic effect and whether high-frequency stimulation of different areas differentially affect unconditioned (innate) and conditioned (learned) anxiety. In this study, we examined the effect of stimulation in five brain areas in rats (NAc core and shell, bed nucleus of the stria terminalis (BNST), internal capsule (IC) and the ventral medial caudate nucleus (CAU)). The elevated plus maze was used to test the effect of stimulation on unconditioned anxiety, the Vogel conflict test for conditioned anxiety, and an activity test for general locomotor behaviour. We found different anxiolytic effects of stimulation in the five target areas. Stimulation of the CAU decreased both conditioned and unconditioned anxiety, while stimulation of the IC uniquely reduced conditioned anxiety. Remarkably, neither the accumbens nor the BNST stimulation affected conditioned or unconditioned anxiety. Locomotor activity increased with NAc core stimulation but decreased with the BNST. These findings suggest that (1) DBS may have a differential effect on unconditioned and conditioned anxiety depending on the stimulation area, and that (2) stimulation of the IC exclusively reduces conditioned anxiety. This suggests that the anxiolytic effects of DBS seen in OCD patients may not be induced by stimulation of the NAc, but rather by the IC. PMID:23900312

  2. Exploring Selective Neural Electrical Stimulation for Upper Limb Function Restoration

    PubMed Central

    Tigra, Wafa; Guiraud, David; Andreu, David; Coulet, Bertrand; Gelis, Anthony; Fattal, Charles; Maciejasz, Pawel; Picq, Chloé; Rossel, Olivier; Teissier, Jacques; Coste, Christine Azevedo

    2016-01-01

    This article introduces a new approach of selective neural electrical stimulation of the upper limb nerves. Median and radial nerves of individuals with tetraplegia are stimulated via a multipolar cuff electrode to elicit movements of wrist and hand in acute conditions during a surgical intervention. Various configurations corresponding to various combinations of a 12-poles cuff electrode contacts are tested. Video recording and electromyographic (EMG) signals recorded via sterile surface electrodes are used to evaluate the selectivity of each stimulation configuration in terms of activated muscles. In this abstract we introduce the protocol and preliminary results will be presented during the conference. PMID:27478571

  3. Mechanisms of Cochlear Stimulation Through the Round Window

    NASA Astrophysics Data System (ADS)

    Lukashkin, Andrei N.; Weddell, Thomas; Russell, Ian J.

    2011-11-01

    The round window membrane (RW) functions as a pressure relief valve in conventional hearing allowing structures of the middle ear to move. Investigations in recent years have shown that middle ear implants can be used to stimulate the cochlea via the RW. Isolated clinical uses of this technique have been applied but more thorough theoretical and empirical studies are required. Using guinea pigs as test subjects we have investigated physiological effects of RW stimulation using a simulation of active middle ear prosthesis, a cylindrical neodymium iron boron disk magnet placed upon the RW which can be stimulated by an electromagnetic coil positioned in close proximity to the magnet.

  4. Nanomaterial-Enabled Neural Stimulation.

    PubMed

    Wang, Yongchen; Guo, Liang

    2016-01-01

    Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a high spatial resolution and cell-type specificity. In these techniques, a nanomaterial converts a remotely transmitted primary stimulus such as a light, magnetic or ultrasonic signal to a localized secondary stimulus such as an electric field or heat to stimulate neurons. The ease of surface modification and bio-conjugation of nanomaterials facilitates cell-type-specific targeting, designated placement and highly localized membrane activation. This review focuses on nanomaterial-enabled neural stimulation techniques primarily involving opto-electric, opto-thermal, magneto-electric, magneto-thermal and acousto-electric transduction mechanisms. Stimulation techniques based on other possible transduction schemes and general consideration for these emerging neurotechnologies are also discussed.

  5. Nanomaterial-Enabled Neural Stimulation

    PubMed Central

    Wang, Yongchen; Guo, Liang

    2016-01-01

    Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a high spatial resolution and cell-type specificity. In these techniques, a nanomaterial converts a remotely transmitted primary stimulus such as a light, magnetic or ultrasonic signal to a localized secondary stimulus such as an electric field or heat to stimulate neurons. The ease of surface modification and bio-conjugation of nanomaterials facilitates cell-type-specific targeting, designated placement and highly localized membrane activation. This review focuses on nanomaterial-enabled neural stimulation techniques primarily involving opto-electric, opto-thermal, magneto-electric, magneto-thermal and acousto-electric transduction mechanisms. Stimulation techniques based on other possible transduction schemes and general consideration for these emerging neurotechnologies are also discussed. PMID:27013938

  6. Vagal Nerve Stimulation Therapy: What Is Being Stimulated?

    PubMed Central

    Kember, Guy; Ardell, Jeffrey L.; Armour, John A.; Zamir, Mair

    2014-01-01

    Vagal nerve stimulation in cardiac therapy involves delivering electrical current to the vagal sympathetic complex in patients experiencing heart failure. The therapy has shown promise but the mechanisms by which any benefit accrues is not understood. In this paper we model the response to increased levels of stimulation of individual components of the vagal sympathetic complex as a differential activation of each component in the control of heart rate. The model provides insight beyond what is available in the animal experiment in as much as allowing the simultaneous assessment of neuronal activity throughout the cardiac neural axis. The results indicate that there is sensitivity of the neural network to low level subthreshold stimulation. This leads us to propose that the chronic effects of vagal nerve stimulation therapy lie within the indirect pathways that target intrinsic cardiac local circuit neurons because they have the capacity for plasticity. PMID:25479368

  7. REAL-TIME TRACER MONITORING OF RESERVOIR STIMULATION PROCEDURES

    SciTech Connect

    George Scott III

    2002-08-01

    Ongoing Phase 2 work comprises the development and field-testing of a real-time reservoir stimulation diagnostic system. Phase 3 work commenced in June 2001, and involved conducting research, development and field-testing of real-time enhanced dual-fluid stimulation processes. Experimental field-testing to date includes three well tests. Application of these real-time stimulation processes and diagnostic technologies has been technically successful with commercial production from the ''marginal'' reservoirs in the first two well tests. The third well test proved downhole-mixing is an efficient process for acid stimulation of a carbonate reservoir that produced oil and gas with 2200 psi bottomhole reservoir pressure, however, subsequent shut-in pressure testing indicated the reservoir was characterized by low-permeability. Realtimezone continues to seek patent protection in foreign markets to the benefit of both RTZ and NETL. Realtimezone and the NETL have licensed the United States patented to Halliburton Energy Services (HES). Ongoing Phase 2 and Phase 3 field-testing continues to confirm applications of both real-time technologies, from well testing conducted over the last 12-month work period and including well test scheduled for year-end of 2002. Technical data transfer to industry is ongoing via Internet tech-transfer, public presentations and industry publications. Final Phase 3 test work will be focused on further field-testing the innovational process of blending stimulation fluids downhole. This system provides a number of advantages in comparison to older industry fracturing techniques and allows the operator to control reservoir fracture propagation and concentrations of proppant placed in the reservoir, in real-time. Another observed advantage is that lower friction pressures result, which results in lower pump treating pressures and safer reservoir hydraulic fracturing jobs.

  8. Digital electronic bone growth stimulator

    DOEpatents

    Kronberg, J.W.

    1995-05-09

    A device is described for stimulating bone tissue by applying a low level alternating current signal directly to the patient`s skin. A crystal oscillator, a binary divider chain and digital logic gates are used to generate the desired waveforms that reproduce the natural electrical characteristics found in bone tissue needed for stimulating bone growth and treating osteoporosis. The device, powered by a battery, contains a switch allowing selection of the correct waveform for bone growth stimulation or osteoporosis treatment so that, when attached to the skin of the patient using standard skin contact electrodes, the correct signal is communicated to the underlying bone structures. 5 figs.

  9. Digital electronic bone growth stimulator

    DOEpatents

    Kronberg, James W.

    1995-01-01

    A device for stimulating bone tissue by applying a low level alternating current signal directly to the patient's skin. A crystal oscillator, a binary divider chain and digital logic gates are used to generate the desired waveforms that reproduce the natural electrical characteristics found in bone tissue needed for stimulating bone growth and treating osteoporosis. The device, powered by a battery, contains a switch allowing selection of the correct waveform for bone growth stimulation or osteoporosis treatment so that, when attached to the skin of the patient using standard skin contact electrodes, the correct signal is communicated to the underlying bone structures.

  10. A review of 25 years of the social interaction test.

    PubMed

    File, Sandra E; Seth, Pallab

    2003-02-28

    The social interaction test of anxiety was developed 25 years ago to provide an ethologically based test that was sensitive to both anxiolytic and anxiogenic effects. It is sensitive to a number of environmental and physiological factors that can affect anxiety. It has detected anxiogenic effects of peptides such as corticotropin-releasing factor (CRF) and adrenocorticotropic hormone (ACTH), and anxiolytic effects of neuropeptide Y and substance P receptor antagonists. It has successfully identified neuropharmacological sites of action of anxiogenic compounds and drug withdrawal. Effects of compounds acting on the gamma-aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT) systems have been extensively investigated after both systemic administration and microinjection into specific brain regions. The use of this test has, thus, played a crucial role in unravelling the neural basis of anxiety. It is hoped that in the next 25 years, the test will play a crucial role in determining the genetic basis of anxiety disorders.

  11. Magnetically stimulated fluid flow patterns

    ScienceCinema

    Martin, Jim; Solis, Kyle

    2016-07-12

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  12. Demultiplexer circuit for neural stimulation

    DOEpatents

    Wessendorf, Kurt O; Okandan, Murat; Pearson, Sean

    2012-10-09

    A demultiplexer circuit is disclosed which can be used with a conventional neural stimulator to extend the number of electrodes which can be activated. The demultiplexer circuit, which is formed on a semiconductor substrate containing a power supply that provides all the dc electrical power for operation of the circuit, includes digital latches that receive and store addressing information from the neural stimulator one bit at a time. This addressing information is used to program one or more 1:2.sup.N demultiplexers in the demultiplexer circuit which then route neural stimulation signals from the neural stimulator to an electrode array which is connected to the outputs of the 1:2.sup.N demultiplexer. The demultiplexer circuit allows the number of individual electrodes in the electrode array to be increased by a factor of 2.sup.N with N generally being in a range of 2-4.

  13. Magnetically stimulated fluid flow patterns

    SciTech Connect

    Martin, Jim; Solis, Kyle

    2014-03-06

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  14. Evoked response to taste stimulations.

    PubMed

    Wada, Masashi

    2005-01-01

    For the recording of gustatory evoked responses, the tip of a stimulator is pressed vertically on one side of the tongue until the trigger pulses are generated by a switch attached to the bottom of the stimulator. According to our results, no detectable response was observed in the absence of taste. The positive waves were distinguishable by using the technique of superimposition before averaging, and the positive wave was made clearer by averaging.

  15. Geothermal Reservoir Well Stimulation Program: technology transfer

    SciTech Connect

    Not Available

    1980-05-01

    The following are included: review of available data from previous fracturing stimulation operations, stimulation process variables, fracturing fluid design, hydraulic fracture design, stimulation case histories, and selected bibliography. (MHR)

  16. 95 stimulations in 63 wells

    SciTech Connect

    Horton, A.I.

    1982-02-01

    Since 1976, extensive studies on the nature of the Eastern gas shales and the production potential from stimulated shale wells have been conducted through joint efforts of industry and the Department of Energy (DOE). Prior to development of this project, the conventional method of stimulating the shales was borehole shooting, and conventional hydraulic fracturing of the shale was just beginning. DOE-industry investigations under the Eastern Gas Shales Project have experimented with other types of stimulations, including massive hydraulic fracturing, foam fracturing, cryogenic fracturing, chemical explosives, and novel treatments. Two of the latter have used (1) nitrogen and (2) oil assisted with nitrogen. Two other treatments, which were unsuccessful, were (1) an open hole packer-stage frac and (2) a kerosene frac. These were operational and conceptual failures. Details of the stimulations and production data, where available, have been complied and studied. The experience that has been gained may prove helpful to those considering stimulation technology in future well drilling ventures in the shale. However, the limited data available in regions of similar geologic factors preclude a thorough analysis of stimulation effectiveness.

  17. Brain Stimulation for Torsion Dystonia

    PubMed Central

    Fox, Michael D.; Alterman, Ron L.

    2016-01-01

    Dystonia is a heterogeneous neurological disorder characterized by abnormal muscle contractions for which standard medical therapy is often inadequate. For such patients, therapeutic brain stimulation is becoming increasingly utilized. Here we review the evidence and effect sizes for treating different types of dystonia with different types of brain stimulation. Strong (level B) evidence supports the use of deep brain stimulation (DBS) for the treatment of primary generalized or segmental dystonia, especially DYT-1, as well as for patients with cervical dystonia. Large effect sizes have also been reported for DBS treatment of tardive dystonia, writer’s cramp, cranial dystonia, myoclonus dystonia, and off-state dystonia associated with Parkinson’s disease. Lesser benefit is generally seen in dystonia secondary to structural brain damage. Other brain stimulation techniques including epidural cortical stimulation and noninvasive brain stimulation have been investigated, but generally report smaller effect sizes in a more limited number of patients. Recent advances relevant to patient selection, surgical approach, DBS programming, and mechanism of action are discussed. PMID:25894231

  18. Boosting brain excitability by transcranial high frequency stimulation in the ripple range

    PubMed Central

    Moliadze, Vera; Antal, Andrea; Paulus, Walter

    2010-01-01

    Alleviating the symptoms of neurological diseases by increasing cortical excitability through transcranial stimulation is an ongoing scientific challenge. Here, we tackle this issue by interfering with high frequency oscillations (80–250 Hz) via external application of transcranial alternating current stimulation (tACS) over the human motor cortex (M1). Twenty-one subjects participated in three different experimental studies and they received on separate days tACS at three frequencies (80 Hz, 140 Hz and 250 Hz) and sham stimulation in a randomized order. tACS with 140 Hz frequency increased M1 excitability as measured by transcranial magnetic stimulation-generated motor evoked potentials (MEPs) during and for up to 1 h after stimulation. Control experiments with sham and 80 Hz stimulation were without any effect, and 250 Hz stimulation was less efficient with a delayed excitability induction and reduced duration. After-effects elicited by 140 Hz stimulation were robust against inversion of test MEP amplitudes seen normally under activation. Stimulation at 140 Hz reduced short interval intracortical inhibition, but left intracortical facilitation, long interval cortical inhibition and cortical silent period unchanged. Implicit motor learning was not facilitated by 140 Hz stimulation. High frequency stimulation in the ripple range is a new promising non-invasive brain stimulation protocol to increase human cortical excitability during and after the end of stimulation. PMID:20962008

  19. Boosting brain excitability by transcranial high frequency stimulation in the ripple range.

    PubMed

    Moliadze, Vera; Antal, Andrea; Paulus, Walter

    2010-12-15

    Alleviating the symptoms of neurological diseases by increasing cortical excitability through transcranial stimulation is an ongoing scientific challenge. Here, we tackle this issue by interfering with high frequency oscillations (80–250 Hz) via external application of transcranial alternating current stimulation (tACS) over the human motor cortex (M1). Twenty-one subjects participated in three different experimental studies and they received on separate days tACS at three frequencies (80 Hz, 140 Hz and 250 Hz) and sham stimulation in a randomized order. tACS with 140 Hz frequency increased M1 excitability as measured by transcranial magnetic stimulation-generated motor evoked potentials (MEPs) during and for up to 1 h after stimulation. Control experiments with sham and 80 Hz stimulation were without any effect, and 250 Hz stimulation was less efficient with a delayed excitability induction and reduced duration. After-effects elicited by 140 Hz stimulation were robust against inversion of test MEP amplitudes seen normally under activation. Stimulation at 140 Hz reduced short interval intracortical inhibition, but left intracortical facilitation, long interval cortical inhibition and cortical silent period unchanged. Implicit motor learning was not facilitated by 140 Hz stimulation. High frequency stimulation in the ripple range is a new promising non-invasive brain stimulation protocol to increase human cortical excitability during and after the end of stimulation.

  20. Mechanisms of osteocyte stimulation in osteoporosis.

    PubMed

    Verbruggen, Stefaan W; Vaughan, Ted J; McNamara, Laoise M

    2016-09-01

    Experimental studies have shown that primary osteoporosis caused by oestrogen-deficiency results in localised alterations in bone tissue properties and mineral composition. Additionally, changes to the lacunar-canalicular architecture surrounding the mechanosensitive osteocyte have been observed in animal models of the disease. Recently, it has also been demonstrated that the mechanical stimulation sensed by osteocytes changes significantly during osteoporosis. Specifically, it was shown that osteoporotic bone cells experience higher maximum strains than healthy bone cells after short durations of oestrogen deficiency. However, in long-term oestrogen deficiency there was no significant difference between bone cells in healthy and normal bone. The mechanisms by which these changes arise are unknown. In this study, we test the hypothesis that complex changes in tissue composition and lacunar-canalicular architecture during osteoporosis alter the mechanical stimulation of the osteocyte. The objective of this research is to employ computational methods to investigate the relationship between changes in bone tissue composition and microstructure and the mechanical stimulation of osteocytes during osteoporosis. By simulating physiological loading, it was observed that an initial decrease in tissue stiffness (of 0.425GPa) and mineral content (of 0.66wt% Ca) relative to controls could explain the mechanical stimulation observed at the early stages of oestrogen deficiency (5 weeks post-OVX) during in situ bone cell loading in an oestrogen-deficient rat model of post-menopausal osteoporosis (Verbruggen et al., 2015). Moreover, it was found that a later increase in stiffness (of 1.175GPa) and mineral content (of 1.64wt% Ca) during long-term osteoporosis (34 weeks post-OVX), could explain the mechanical stimuli previously observed at a later time point due to the progression of osteoporosis. Furthermore, changes in canalicular tortuosity arising during osteoporosis were shown

  1. Auricular electrical stimulation and dental pain threshold.

    PubMed Central

    Simmons, M. S.; Oleson, T. D.

    1993-01-01

    A modified double-blind evaluation of naloxone reversibility of dental analgesia produced by auricular electrical stimulation (AES) was examined in 40 subjects assigned randomly to one of four groups: AES followed by saline (AS), AES followed by naloxone (AN), placebo AES followed by saline (PS), and placebo AES followed by naloxone (PN). Dental pain threshold was tested using a hand-held dental pulp tester. A second investigator administered the true or placebo AES using an electrical stimulator. A third investigator injected intravenously saline or naloxone. The subjects and investigators 1 and 3 were blind to all treatment conditions. A repeated measures analysis of variance revealed a significant difference among the four groups. The AES groups exhibited a statistically significant 18% elevation of pain threshold, whereas the two placebo stimulation groups (PS and PN) remained essentially unchanged. The mean pain threshold increased to more than 23% for group AS, but fell to less than 12% for the subjects in group AN, who were given naloxone. These findings indicate a small but significant elevation of pain threshold by AES, an effect partially blocked by naloxone, suggesting an endogenous opioid system as one mechanism for AES analgesia. Images Figure 1 Figure 2 PMID:8185085

  2. Transcranial Alternating Current Stimulation with Sawtooth Waves: Simultaneous Stimulation and EEG Recording.

    PubMed

    Dowsett, James; Herrmann, Christoph S

    2016-01-01

    Transcranial alternating current stimulation (tACS) has until now mostly been administered as an alternating sinusoidal wave. Despite modern tACS stimulators being able to deliver alternating current with any arbitrary shape there has been no systematic exploration into the relative benefits of different waveforms. As tACS is a relatively new technique there is a huge parameter space of unexplored possibilities which may prove superior or complimentary to the traditional sinusoidal waveform. Here, we begin to address this with an investigation into the effects of sawtooth wave tACS on individual alpha power. Evidence from animal models suggests that the gradient and direction of an electric current should be important factors for the subsequent neural firing rate; we compared positive and negative ramp sawtooth waves to test this. An additional advantage of sawtooth waves is that the resulting artifact in the electroencephalogram (EEG) recording is significantly simpler to remove than a sine wave; accordingly we were able to observe alpha oscillations both during and after stimulation. We found that positive ramp sawtooth, but not negative ramp sawtooth, significantly enhanced alpha power during stimulation relative to sham (p < 0.01). In addition we tested for an after-effect of both sawtooth and sinusoidal stimulation on alpha power but in this case did not find any significant effect. This preliminary study paves the way for further investigations into the effect of the gradient and direction of the current in tACS which could significantly improve the usefulness of this technique. PMID:27065835

  3. Theoretical investigation on the pumping effect of stimulated Brillouin scattering on stimulated Raman scattering in water

    NASA Astrophysics Data System (ADS)

    Shi, J.; Chen, X.; Ouyang, M.; Gong, W.; Su, Y.; Liu, D.

    2012-02-01

    The pumping effect of stimulated Brillouin scattering on stimulated Raman scattering is investigated theoretically through the coupled wave equations of stimulated Brillouin scattering and stimulated Raman scattering. The numerical simulations are in agreement with the experimental results. They indicate that the backward stimulated Raman scattering is excited and amplified collectively by both pump laser and stimulated Brillouin scattering.

  4. Emerging neural stimulation technologies for bladder dysfunctions.

    PubMed

    Lee, Jee Woong; Kim, Daejeong; Yoo, Sangjin; Lee, Hyungsup; Lee, Gu-Haeng; Nam, Yoonkey

    2015-03-01

    In the neural engineering field, physiological dysfunctions are approached by identifying the target nerves and providing artificial stimulation to restore the function. Neural stimulation and recording technologies play a central role in this approach, and various engineering devices and stimulation techniques have become available to the medical community. For bladder control problems, electrical stimulation has been used as one of the treatments, while only a few emerging neurotechnologies have been used to tackle these problems. In this review, we introduce some recent developments in neural stimulation technologies including microelectrode array, closed-loop neural stimulation, optical stimulation, and ultrasound stimulation.

  5. Neuroprotection trek--the next generation: neuromodulation I. Techniques--deep brain stimulation, vagus nerve stimulation, and transcranial magnetic stimulation

    NASA Technical Reports Server (NTRS)

    Andrews, Russell J.

    2003-01-01

    Neuromodulation denotes controlled electrical stimulation of the central or peripheral nervous system. The three forms of neuromodulation described in this paper-deep brain stimulation, vagus nerve stimulation, and transcranial magnetic stimulation-were chosen primarily for their demonstrated or potential clinical usefulness. Deep brain stimulation is a completely implanted technique for improving movement disorders, such as Parkinson's disease, by very focal electrical stimulation of the brain-a technique that employs well-established hardware (electrode and pulse generator/battery). Vagus nerve stimulation is similar to deep brain stimulation in being well-established (for the treatment of refractory epilepsy), completely implanted, and having hardware that can be considered standard at the present time. Vagus nerve stimulation differs from deep brain stimulation, however, in that afferent stimulation of the vagus nerve results in diffuse effects on many regions throughout the brain. Although use of deep brain stimulation for applications beyond movement disorders will no doubt involve placing the stimulating electrode(s) in regions other than the thalamus, subthalamus, or globus pallidus, the use of vagus nerve stimulation for applications beyond epilepsy-for example, depression and eating disorders-is unlikely to require altering the hardware significantly (although stimulation protocols may differ). Transcranial magnetic stimulation is an example of an external or non-implanted, intermittent (at least given the current state of the hardware) stimulation technique, the clinical value of which for neuromodulation and neuroprotection remains to be determined.

  6. Electrical stimulation of the dorsolateral prefrontal cortex improves memory monitoring.

    PubMed

    Chua, Elizabeth F; Ahmed, Rifat

    2016-05-01

    The ability to accurately monitor one's own memory is an important feature of normal memory function. Converging evidence from neuroimaging and lesion studies have implicated the dorsolateral prefrontal cortex (DLPFC) in memory monitoring. Here we used high definition transcranial direct stimulation (HD-tDCS), a non-invasive form of brain stimulation, to test whether the DLPFC has a causal role in memory monitoring, and the nature of that role. We used a metamemory monitoring task, in which participants first attempted to recall the answer to a general knowledge question, then gave a feeling-of-knowing (FOK) judgment, followed by a forced choice recognition task. When participants received DLPFC stimulation, their feeling-of-knowing judgments were better predictors of memory performance, i.e., they had better memory monitoring accuracy, compared to stimulation of a control site, the anterior temporal lobe (ATL). Effects of DLPFC stimulation were specific to monitoring accuracy, as there was no significant increase in memory performance, and if anything, there was poorer memory performance with DLPFC stimulation. Thus we have demonstrated a causal role for the DLPFC in memory monitoring, and showed that electrically stimulating the left DLPFC led people to more accurately monitor and judge their own memory. PMID:26970142

  7. Electrical stimulation of mechanoreceptors

    NASA Astrophysics Data System (ADS)

    Echenique, A. M.; Graffigna, J. P.

    2011-12-01

    Within the field of Rehabilitation Engineering, this work is aimed at identifying the optimal parameters of electric current stimulus which activate the nervous axons of mecanoreceptors found in the fingertip, allowing, this way, to resemble tactile senses. These sensorial feelings can be used by aiding technological means, namely, the sensorial substitution technology, in an attempt to render information to blind people through the tactile sense. The physical pressure on sensorial areas (fingertips) used for reading activities through the Braille System is the main effect that is imitated and studied in this research work. An experimental aiding prototype for Braille reading research has been developed and tested with blinds and reduced vision people, with highly satisfactory results.

  8. Influence of Passive and Active Vestibular Stimulation and Balance of Young Children.

    ERIC Educational Resources Information Center

    Gabert, Trent E.; And Others

    1982-01-01

    Sixty six-to eight-year-olds with below-average scores on three balance tests received active, passive or no vestibular stimulation over a five-week period. Balance scores improved for all groups on one or more tests. Improvement could not be related to vestibular stimulation. (Author/RD)

  9. Hydraulic driven fast and precise nonmagnetic tactile stimulator for neurophysiological and MEG measurements.

    PubMed

    Broser, Philip J; Braun, Christoph

    2012-10-01

    Electric stimulation of the peripheral nerves is well established as a diagnostic and research tool to analyze the somatosensory system. However, electric stimulation has some disadvantages. Electric stimulation of the median nerve triggers action potentials in all fiber populations of the nerve. Electric stimulation further creates artifacts and courses discomfort which is usually not well tolerated in the awake child. Therefore, the development of a more specific stimulation has constantly been a goal in recent years. There have been several approaches in the past to deliver somatic stimulation. However, all of them failed short in some aspects. In this study, a new type of somatosensory stimulator device was developed and compared against the gold standard of electric stimulation. The stimulation is achieved by repetitive tactile stimulation of the index finger using a blunt needle. In contrast to all previous approaches, we use a hydraulic system to move the needle up and downward. Given that water is very well suited to conduct pressure pulses it is possible to place the tactile stimulator device holding the needle close to the subject and the hydraulic driving system outside a critical area. Using a phantom, we showed that our stimulator is capable of delivering a stimulus precise on the submillisecond time scale. In addition, we test our stimulator on a healthy adult and compare the results against the electric stimulation. We can show the feasibility of measuring the electric responses of the peripheral nerve and while using MEG also the response of the primary somatosensory cortex. The tactile stimulation showed a more spatial focuses activation of the primary somatosensory cortex when compared against the electric stimulation. The proposed high-precision tactile stimulator will make it possible to analyze the somatosensory system noninvasively in children in the future.

  10. A 96-channel neural stimulation system for driving AIROF microelectrodes.

    PubMed

    Hu, Z; Troyk, P; Cogan, S

    2004-01-01

    We present the design and testing of a 96-channel stimulation system to drive activated iridium oxide (AIROF) microelectrodes within safe charge-injection limits. Our system improves upon the traditional capacitively coupled, symmetric charge-balanced biphasic stimulation waveform so as to maximize charge-injection capacity without endangering the microelectrodes. It can deliver computer-controlled cathodic current pulse for to up to 96 AIROF microelectrodes and positively bias them during the inter-pulse interval. The stimulation system is comprised of (1) 12 custom-designed PCB boards each hosting an 8-channel ASIC chip, (2) a motherboard to communicate between these 12 boards and the PC, (3) the PC interface equipped with a DIO card and the corresponding software. We plan to use this system in animal experiments for intracortical neural stimulation of implanted electrodes within our visual prosthesis project. PMID:17271241

  11. Cleanup/stimulation of a horizontal wellbore using propellants

    SciTech Connect

    Rougeot, J.E.; Lauterbach, K.A.

    1993-01-01

    This report documents the stimulation/cleanup of a horizontal well bore (Wilson 25) using propellants. The Wilson 25 is a Bartlesville Sand well located in the Flatrock Field, Osage County, Oklahoma. The Wilson 25 was drilled to determine if horizontal drilling could be used as a means to economically recover primary oil that had been left in place in a mostly abandoned oil field because of the adverse effects of water coning. Pump testing of the Wilson 25 horizontal well bore before cleanup or stimulation produced 6 barrels of oil and .84 barrels of water per day. The high percentage of daily oil production to total daily fluid production indicated that the horizontal well bore had accessed potentially economical oil reserves if the fluid production rate could be increased by performing a cleanup/stimulation treatment. Propellants were selected as an inexpensive means to stimulate and cleanup the near well bore area in a uniform manner. The ignition of a propellant creates a large volume of gas which penetrates the formation, creating numerous short cracks through which hydrocarbons can travel into the well bore. More conventional stimulation/cleanup techniques were either significantly more expensive, less likely to treat uniformly, or could not be confined to the near well bore area. Three different propellant torpedo designs were tested with a total of 304' of horizontal well bore being shot and producible. The initial test shot caused 400' of the horizontal well bore to become plugged off, and subsequently it could not be production tested. The second and third test shots were production tested, with the oil production being increased 458% and 349%, respectively, on a per foot basis. The Wilson 25 results indicate that a propellant shot treatment is an economically viable means to cleanup/stimulate a horizontal well bore.

  12. Pain as a stressor: effects of prior nociceptive stimulation on escape responding of rats to thermal stimulation.

    PubMed

    Vierck, Charles J; Green, Megan; Yezierski, Robert P

    2010-01-01

    In our previous studies, psychological stress was shown to enhance operant escape responding of male and female rats. The stressors that produced hyperalgesia were physical restraint and social defeat. Nociceptive input also elicits stress reactions, generating the prediction that pain would facilitate pain under certain circumstances. For example, the usual method of evaluating stress in laboratory animals is to test for effects after termination of the stressor. Accordingly, operant escape performance of male and female rats was evaluated during two successive trials involving nociceptive thermal stimulation. The intent was to determine whether nociceptive sensitivity differed on first trials and during pain-induced stress on second trials. Compared to a first trial of 44.5 degrees C stimulation, escape responding increased during a second trial of 44.5 degrees C stimulation (preceded by an escape trial of 10 degrees C). Similarly, escape from cold (10 degrees C) was enhanced when preceded by escapable 44.5 degrees C stimulation. Thus, prior nociceptive stimulation enhanced escape from aversive thermal stimulation. Facilitation of pain by a preceding pain experience is consistent with stress-induced hyperalgesia and contrasts with other models of pain inhibition by concurrent nociceptive stimulation. PMID:19261494

  13. Deep brain stimulation: new techniques.

    PubMed

    Hariz, Marwan

    2014-01-01

    The technology of the hardware used in deep brain stimulation (DBS), and the mode of delivering the stimulation have not significantly evolved since the start of the modern era of DBS 25 years ago. However, new technology is now being developed along several avenues. New features of the implantable pulse generator (IPG) allow fractionation of the electric current into variable proportions between different contacts of the multi-polar lead. Another design consists in leads that allow selective current steering from directionally placed electrode contacts that would deliver the stimulation in a specific direction or even create a directional shaped electric field that would conform to the anatomy of the brain target aimed at, avoiding adjacent structures, and thus avoiding side effects. Closed loop adaptive stimulation technologies are being developed, allowing a tracking of the pathological local field potential of the brain target, and delivering automatically the stimulation to suppress the pathological activity as soon as it is detected and for as long as needed. This feature may contribute to a DBS therapy "on demand", instead of continuously. Finally, advances in imaging technology are providing "new" brain targets, and increasingly allowing DBS to be performed accurately while avoiding the risks of microelectrode recording. PMID:24262179

  14. Evoked Electromyographically Controlled Electrical Stimulation

    PubMed Central

    Hayashibe, Mitsuhiro

    2016-01-01

    Time-variant muscle responses under electrical stimulation (ES) are often problematic for all the applications of neuroprosthetic muscle control. This situation limits the range of ES usage in relevant areas, mainly due to muscle fatigue and also to changes in stimulation electrode contact conditions, especially in transcutaneous ES. Surface electrodes are still the most widely used in noninvasive applications. Electrical field variations caused by changes in the stimulation contact condition markedly affect the resulting total muscle activation levels. Fatigue phenomena under functional electrical stimulation (FES) are also well known source of time-varying characteristics coming from muscle response under ES. Therefore, it is essential to monitor the actual muscle state and assess the expected muscle response by ES so as to improve the current ES system in favor of adaptive muscle-response-aware FES control. To deal with this issue, we have been studying a novel control technique using evoked electromyography (eEMG) signals to compensate for these muscle time-variances under ES for stable neuroprosthetic muscle control. In this perspective article, I overview the background of this topic and highlight important points to be aware of when using ES to induce the desired muscle activation regardless of the time-variance. I also demonstrate how to deal with the common critical problem of ES to move toward robust neuroprosthetic muscle control with the Evoked Electromyographically Controlled Electrical Stimulation paradigm. PMID:27471448

  15. Laser stimulation for pain research

    NASA Astrophysics Data System (ADS)

    Clark, Stuart; Dickinson, Mark R.; King, Terence A.; Jones, Anthony; Chen, Andrew; Derbyshire, Stuart; Townsend, D. W.; Kinahan, Paul E.; Mintun, M. A.; Nichols, T.

    1996-01-01

    Pain is a serious medical problem; it inflicts huge economic loss and personal suffering. Pain signals are conducted via small, non- and partially myelinated A-delta and C nerve fibers and lasers are particularly well suited to stimulating these fibers. Large myelinated fibers convey touch and vibration information and these fibers are also discharged when contact thermodes and other touch pain stimuli are used and this would give a more muddled signal for functional imaging experiments. The advantages of lasers over conventional methods of pain stimulation are good temporal resolution, no variable parameters are involved such as contact area and they give very reproducible results. Accurate inter-stimulus changes can be achieved by computer control of the laser pulse duration, pulse height and repetition rate and this flexibility enables complex stimulation paradigms to be realized. We present a flexible carbon dioxide laser system designed to generate these stimuli for the study of human cerebral pain responses. We discuss the advantages within research of this system over other methods of pain stimulation such as thermal, electrical and magnetic. The stimulator is used in conjunction with functional magnetic resonance imaging, positron emission tomography and electrophysiological methods of imaging the brain's activity. This combination is a powerful tool for the study of pain-induced activity in different areas of the brain. An accurate understanding of the brain's response to pain will help in research into the areas of rheumatoid arthritis and chronic back pain.

  16. Mini-coil for magnetic stimulation in the behaving primate.

    PubMed

    Tischler, Hadass; Wolfus, Shuki; Friedman, Alexander; Perel, Eli; Pashut, Tamar; Lavidor, Michal; Korngreen, Alon; Yeshurun, Yosef; Bar-Gad, Izhar

    2011-01-15

    Transcranial magnetic stimulation (TMS) is rapidly becoming a leading method in both cognitive neuroscience and clinical neurology. However, the cellular and network level effects of stimulation are still unclear and their study relies heavily on indirect physiological measurements in humans. Direct electrophysiological studies of the effect of magnetic stimulation on neuronal activity in behaving animals are severely limited by both the size of the stimulating coils, which affect large regions of the animal brain, and the large artifacts generated on the recording electrodes. We present a novel mini-coil which is specifically aimed at studying the neurophysiological mechanism of magnetic stimulation in behaving primates. The mini-coil fits into a chronic recording chamber and provides focal activation of brain areas while enabling simultaneous extracellular multi-electrode recordings. We present a comparison of this coil to a commercial coil based on the theoretical and recorded magnetic fields and induced electric fields they generate. Subsequently, we present the signal recorded in the behaving primate during stimulation and demonstrate the ability to extract the spike trains of multiple single units from each of the electrodes with minimal periods affected by the stimulus artifact (median period <2.5 ms). The directly recorded effect of the magnetic stimulation on cortical neurons is in line with peripheral recordings obtained in humans. This novel mini-coil is a key part of the infrastructure for studying the neurophysiological basis of magnetic stimulation, thereby enabling the development and testing of better magnetic stimulation tools and protocols for both neuroscientists and clinicians. PMID:20974177

  17. Tremor entrainment by patterned low-frequency stimulation.

    PubMed

    Barnikol, Utako B; Popovych, Oleksandr V; Hauptmann, Christian; Sturm, Volker; Freund, Hans-Joachim; Tass, Peter A

    2008-10-13

    High-frequency test stimulation for tremor suppression is a standard procedure for functional target localization during deep brain stimulation. This method does not work in cases where tremor vanishes intraoperatively, for example, due to general anaesthesia or due to an insertional effect. To overcome this difficulty, we developed a stimulation technique that effectively evokes tremor in a well-defined and quantifiable manner. For this, we used patterned low-frequency stimulation (PLFS), i.e. brief high-frequency pulse trains administered at pulse rates similar to neurons' preferred burst frequency. Unlike periodic single-pulse stimulation, PLFS enables one to convey effective and considerably greater integral charge densities without violation of safety requirements. In a computational investigation of an oscillatory neuronal network temporarily rendered inactive, we found that PLFS evokes synchronized activity, phase locked to the stimulus. While a stronger increase in the amount of synchrony in the neuronal population requires higher stimulus intensities, the portion of synchronously active neurons nevertheless becomes strongly phase locked to PLFS already at weak stimulus intensities. The phase entrainment effect of PLFS turned out to be robust against variations in the stimulation frequency, whereas enhancement of synchrony required precisely tuned stimulation frequencies. We applied PLFS to a patient with spinocerebellar ataxia type 2 (SCA2) with pronounced tremor that disappeared intraoperatively under general anaesthesia. In accordance with our computational results, PLFS evoked tremor, phase locked to the stimulus. In particular, weak PLFS caused low-amplitude, but strongly phase-locked tremor. PLFS test stimulations provided the only functional information about target localization. Optimal target point selection was confirmed by excellent post-operative tremor suppression. PMID:18632457

  18. Newberry Well 55-29 Stimulation Data 2014

    DOE Data Explorer

    Trenton T. Cladouhos

    2015-09-03

    The Newberry Volcano EGS Demonstration in central Oregon, a 5 year project begun in 2010, tests recent technological advances designed to reduce the cost of power generated by EGS in a hot, dry well (NWG 55-29) drilled in 2008. First, the