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Plasma Cortisol Levels (plasma + cortisol_level)
Selected AbstractsOsmoregulatory changes in wedge sole (Dicologoglossa cuneata Moreau, 1881) after acclimation to different environmental salinitiesAQUACULTURE RESEARCH, Issue 7 2009Marcelino Herrera Abstract The osmoregulatory responses of 20 days of acclimation to environmental salinities of 5,, 15,, 25,, 35, and 55, were assessed in juveniles of wedge sole (Dicologoglossa cuneata Moreau, 1881). This sole shows a good capacity to adapt to this range of environmental salinities. A direct linear relationship between environmental salinity and plasma osmolality was observed, with a calculated isosmotic point of 10.4, (284 mOsm kg,1). Na+, K+ -ATPase activity in the gills followed a ,U-shaped' relationship with environmental salinity, and a direct linear relationship in kidney tissue. Plasma cortisol levels were elevated in fish held in extreme salinities, and glucose levels were higher only in the group maintained at the highest environmental salinity. In the liver, a decrease in glycogen, lactate and amino acid contents was observed in specimens acclimated to extreme salinities (5, and 55,), suggesting mobilization of liver metabolites. Metabolite levels in white muscle showed a pattern similar to the liver, with lower values in specimens acclimated to extreme salinities. We conclude that wedge sole is strongly euryhaline, but acclimation to extreme salinities comes with an energetic cost. [source] Plasma cortisol and metabolite level profiles in two isogenic strains of common carp during confinementJOURNAL OF FISH BIOLOGY, Issue 1 2001N. M. Ruane A rapid increase in common carp Cyprinus carpio plasma cortisol levels was noted, in two experiments, after 30 mins of a 3 h net confinement, which was sustained while the fish were held in the nets. After release from the nets, cortisol levels returned to control values in 1 h. Plasma glucose and free fatty acid levels were elevated by the confinement. Glucose was increased after 30 min but returned to basal levels after 22 h of recovery while free fatty acids were not elevated until 3 h of confinement and remained high for the duration of the recovery period. After confinement for 3 h, plasma lactate levels were reduced and remained low for a further 1 h. No change in either plasma triglyceride or cholesterol levels were found during the study. Confinement had no effect on haematocrit levels but blood haemoglobin levels were reduced. In both experiments hypochloraemia occurred in response to confinement. However, values returned to pre-confinement levels 22 h after confinement. These results show that rearing isogenic carp strains, under identical conditions, results in a reproducable response to an acute stressor and that these carp respond in a similar manner to other teleost species. [source] Stress Hormone Dysregulation at Rest and After Serotonergic Stimulation Among Alcohol-Dependent Men With Extended Abstinence and ControlsALCOHOLISM, Issue 5 2001Robert M. Anthenelli Background: Alcohol dependence has been associated with long-lasting alterations in limbic-hypothalamic-pituitary-adrenal (LHPA) axis and serotonin (5-hydroxytryptamine [5-HT]) function. Other conditions that are associated with alcoholism (cigarette smoking and antisocial personality disorder [ASPD]) have been linked with disturbances in these interrelated systems. We evaluated the stress hormone response to 5-HTergic stimulation in alcohol-dependent men with extended abstinence (average abstinence duration, 4.3 months) and controls to determine the relative contributions of alcoholism, cigarette smoking, and ASPD on baseline and provoked plasma cortisol and adrenocorticotropin hormone (ACTH) concentrations. Methods: One hundred nine alcohol-abstinent men with alcohol dependence (62%), habitual smoking (70%), and ASPD (43%) received d,l-fenfluramine (100 mg po) in a randomized, double-blind, placebo-controlled, crossover trial. The group of recovering alcohol-dependent individuals included abstinent primary alcohol-dependent men and alcohol-dependent men with ASPD, whereas the group of non-alcohol-dependent men comprised healthy controls and non-alcohol-dependent men with ASPD. Plasma cortisol and ACTH levels were obtained at AM baseline and at half-hour intervals after drug administration. Subjective ratings of drug response and physiological measures were also obtained at baseline and every 30 min. Results: Abstinent alcohol-dependent men had significantly lower (approximately 20%) AM baseline plasma cortisol concentrations than non-alcohol-dependent men on both challenge days; however, no differences between the groups were observed with regard to resting AM plasma ACTH levels. After adjusting for these baseline differences, recovering alcohol-dependent men (area under curve = 35.6 ± 37.4 [,g/dl] × min) had a twofold greater cortisol response to fenfluramine than non-alcohol-dependent men (area under curve = 17.5 ± 32.5 [,g/dl] × min) (F= 5.1;df= 1,105;p < 0.03). The elevated cortisol response, which occurred primarily along the descending limb of the response curve, was paralleled by a nonsignificant statistical trend for alcohol-dependent men to also exhibit a greater ACTH response to fenfluramine at the 210-min (p < 0.07) and 240-min (p < 0.09) time points as compared with non-alcohol-dependent men. Cigarette smoking and ASPD did not affect hormonal responses, nor could the groups' subjective ratings and physiological measures be distinguished. Conclusions: Alcohol-dependent men with extended abstinence differed from age- and race-matched non-alcohol-dependent men in resting AM and fenfluramine-induced plasma cortisol levels. This dysfunction in glucocorticoid homeostatic mechanisms was associated with alcoholism and not with smoking or ASPD. We also observed a nonsignificant statistical trend for plasma ACTH levels to be elevated among alcohol-dependent men along the descending limb of the response curve. Alcohol-dependent men seemed to have inherited or acquired damage to 5-HT-regulated LHPA axis function, the precise mechanisms and sites of which remain to be determined. [source] HPA-suppressive effects of aqueous clobetasol propionate in the treatment of patients with oral lichen planusJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 9 2010MA Gonzalez-Moles Abstract Background, Oral topical corticosteroids have potential to produce inhibition of the hypothalamus,pituitary,adrenal (HPA) axis. Objective, To assess whether clobetasol propionate (CP) in aqueous solution causes HPA inhibition. Patients and methods, Sixty-two patients with oral lichen planus or oral lichenoid lesions presenting with severe lesions were treated with topical oral 0.05% CP plus 100 000 IU/cm3 nystatin in aqueous solution. Initial treatment of three 5-min mouthwashes (10 mL) daily was reduced, when the response was deemed complete or excellent, to a maintenance treatment of one 5-min mouthwash on alternate days for 6 months; treatment was then withdrawn and patients were followed up for 1 year. HPA function was assessed by plasma cortisol measurement and adrenocorticotropin (ACTH) stimulation at the end of the initial and maintenance treatment regimens. Results, The HPA axis was more frequently inhibited during initial (53/62; 85.5%) vs. maintenance (2/49; 4%) regimens of aqueous CP. Limitations, In patients with morning plasma cortisol levels between 3 and 18 ,g/dL, a normal result for the ACTH stimulation test only moderately reduces the possibility that a patient has secondary adrenal insufficiency. This can be considered a minor limitation in our study, as only three patients required additional assessment with the ACTH stimulation test. Conclusions, Hypothalamus,pituitary,adrenal inhibition is substantial during initial treatment with aqueous CP three times daily. [source] Short periods of prenatal stress affect growth, behaviour and hypothalamo,pituitary,adrenal axis activity in male guinea pig offspringTHE JOURNAL OF PHYSIOLOGY, Issue 3 2005Amita Kapoor Prenatal stress can have profound long-term influences on physiological function throughout the course of life. We hypothesized that focused periods of moderate prenatal stress at discrete time points in late gestation have differential effects on hypothalamo,pituitary,adrenal (HPA) axis function in adult guinea pig offspring, and that changes in HPA axis function will be associated with modification of anxiety-related behaviour. Pregnant guinea pigs were exposed to a strobe light for 2 h on gestational days (GD) 50, 51, 52 (PS50) or 60, 61, 62 (PS60) (gestation length ,70 days). A control group was left undisturbed throughout pregnancy. Behaviour was assessed in male offspring on postnatal day (PND)25 and PND70 by measurement of ambulatory activity and thigmotaxis (wall-seeking behaviour) in a novel open field environment. Subsequent to behavioural testing, male offspring were cannulated (PND75) to evaluate basal and activated HPA axis function. Body weight was significantly decreased in adult PS50 and PS60 offspring and this effect was apparent soon after weaning. The brain-to-body-weight ratio was significantly increased in adult PS50 males. Basal plasma cortisol levels were elevated in PS50 male offspring throughout the 24 h sampling period compared with controls. In response to an ACTH challenge and to exposure to an acute stressor, PS60 male offspring exhibited elevated plasma cortisol responses. Plasma testosterone concentrations were strikingly decreased in PS50 offspring. Thigmotaxis in the novel environment was increased in PS50 male offspring at PND25 and PND70, suggesting increased anxiety in these animals. In conclusion, prenatal stress during critical windows of neuroendocrine development programs growth, HPA axis function, and stress-related behaviour in adult male guinea pig offspring. Further, the nature of the effect is dependant on the timing of the maternal stress during pregnancy. [source] Effects of central administration of glucagon on feed intake and endocrine responses in sheepANIMAL SCIENCE JOURNAL, Issue 6 2009Yohei KUROSE ABSTRACT This study was conducted to investigate effects of glucagon intracerebroventricularly administered on feed intake and endocrine changes in sheep. Four male sheep (48,55 kg BW) were used. The animals were acclimatized to be fed alfalfa hay cubes at 12.00 hour. Human glucagon (40 and 80 µg/0.5 mL) was injected into the lateral ventricle at 12.00 hour. Blood samples were taken every 10 min from 30 min before to 180 min after the glucagon injection. Soon after the injection, the animals were given alfalfa hay cubes, and the amounts of the feed eaten within 2 h were measured. Feed intakes were significantly (P < 0.05) suppressed by 80 µg of glucagon. Plasma glucose levels in control animals were gradually decreased after the feeding, whilst those in glucagon-treated animals were temporarily elevated just after the feeding and then kept higher than control levels. Plasma insulin was abruptly elevated after the feeding and was maintained at higher levels than before the feeding in all treatments. Plasma NEFA concentrations were decreased after the feeding in all treatments. A tendency of increase in plasma cortisol levels occurred in glucagon-injected animals. The present study provides the first evidence that glucagon directly acts on the brain, then inhibiting feeding behavior and inducing endocrine responses in ruminants. [source] Physiological responses of juvenile wedge sole Dicologoglossa cuneata (Moreau) to high stocking densityAQUACULTURE RESEARCH, Issue 7 2009Marcelino Herrera Abstract Physiological responses to a high stocking density were tested in juvenile wedge sole Dicologoglossa cuneata (Moreau). Fish were kept at low (1 kg m,2), medium (3 kg m,2) and high (9 kg m,2) stocking densities for 22 days. No differences in the weight, length, survival and hepatosomatic index were observed among treatments. Basal plasma cortisol and osmolality were found to be directly and positively related to stocking density. A mild increase in plasma glucose was seen at medium density, and plasma protein was elevated at medium and high densities. The liver glucose and glycogen content was inversely related to stocking density. The liver triglyceride level was significantly elevated at the highest density, and the ,-amino acid content decreased at the highest density. In muscle, glucose levels were significantly higher in fish kept at the lowest density; the ,-amino acid content was elevated in fish kept at high density. In conclusion, plasma cortisol levels indicated an increasing stress level depending on the culture density, but significant changes in energy reserves did not occur in tissue (mainly liver and muscle glycogen and glucose reserves were significantly affected). [source] Whole-body corticosteroid and plasma cortisol concentrations in larval and juvenile Atlantic cod Gadus morhua L. following acute stressAQUACULTURE RESEARCH, Issue 13 2006William King V Abstract Methods were developed to assess whole-body immunoreactive corticosteroid concentrations (IRC) and plasma levels of cortisol in Atlantic cod subjected to several common, acute stressors. A measurable corticosteroid stress response was observed at the first sampling in whole bodies of 8-day post-hatch (dph) larvae. Two groups of juveniles (,5 and 30 g) were subjected to a 30 s net stressor and whole-body IRC and plasma cortisol levels were determined. Post-stressor IRC in smaller fish rose approximately 14-fold, peaked at 1 h, were sustained for 3,6 h and returned to pre-stressor levels within 24 h. Post-stressor plasma cortisol levels in larger fish rose approximately 18-fold, peaked at 0.5,1 h, were sustained for 1,3 h and then returned to near pre-stressor levels after 24 h. Immunoreactive corticosteroid concentrations appeared to remain elevated longer than plasma cortisol levels suggesting that steroids other than cortisol were contributing to total immunoreactivity in homogenates. Juveniles exposed to either a grading procedure or high density transport had maximal IRC and plasma cortisol levels within 90 min which returned to pre-stressor levels within 24,72 h. A reduction in water salinity (20 g L,1) did not moderate the corticosteroid response in juveniles. The results show that Atlantic cod respond to common, acute stressors in a manner similar to other teleosts. Whole-body homogenates can be used to identify changes in IRC in response to acute stress in cod with the caveat that recovery IRC may differ from plasma cortisol concentrations. [source] The effect of therapeutic glucocorticoids on the adrenal response in a randomized controlled trial in patients with rheumatoid arthritis,ARTHRITIS & RHEUMATISM, Issue 5 2006John R. Kirwan Objective To measure the effect of low-dose systemic glucocorticoid treatment on the adrenal response to adrenocorticotropic hormone (ACTH) in patients with rheumatoid arthritis (RA). Methods Patients with RA who took part in a randomized double-blind placebo-controlled trial of budesonide (3 mg/day and 9 mg/day) and prednisolone (7.5 mg/day) underwent a short (60-minute) test with injection of ACTH (tetracosactide hexaacetate) at baseline and the day after completing the 3-month treatment program. Plasma cortisol measurements at baseline and 3 months were compared within and between the treatment groups. Individual patients were classified as normal responders to ACTH or as abnormal responders if changes were >2 SD below the pretreatment value in the entire group of study patients. Results Short tests with ACTH injection were performed on 139 patients before beginning the study medication and on 134 patients after cessation of the medication. There were no changes in the placebo group. Mean plasma cortisol levels following treatment were reduced in all active treatment groups. In addition, mean values were significantly reduced for the 30-minute and 60-minute responses to ACTH. The maximum reduction (35%) occurred in the prednisolone group at 60 minutes. Following treatment, 34% of patients taking budesonide 9 mg and 46% of those taking prednisolone 7.5 mg failed to reach the normal maximum cortisol response to ACTH. Four patients failed to achieve the normal percentage increase in cortisol levels, but only 1 patient failed to meet both criteria. Conclusion Low doses of a glucocorticoid resulted in depression of baseline and ACTH-stimulated cortisol levels after 12 weeks of therapy. Although the responsiveness of the hypothalamic,pituitary,adrenal axis in individual patients generally remained within the normal range, these changes should be investigated further. [source] In vivo activity of 11,-hydroxysteroid dehydrogenase type 1 and free fatty acid-induced insulin resistanceCLINICAL ENDOCRINOLOGY, Issue 4 2005K. Mai Summary Introduction, Free fatty acids (FFAs) induce hepatic insulin resistance and enhance hepatic gluconeogenesis. Glucocorticoids (GCs) also stimulate hepatic gluconeogenesis. The aim of this study was to investigate whether the FFA-induced hepatic insulin resistance is mediated by increased activity of hepatic 11,-hydroxysteroid dehydrogenase type 1 (11,-HSD1), accompanied by elevated hepatic cortisol levels. Methods, Following a 10-h overnight fast, six healthy male volunteers were investigated. A euglycaemic hyperinsulinaemic clamp was performed during lipid or saline infusion. To assess hepatic 11,-HSD1 activity, plasma cortisol levels were measured after oral administration of cortisone acetate during lipid or saline infusion. In addition, 11,-HSD activities were determined in vivo by calculating the urinary ratios of GC metabolites. Results, Lipid infusion increased FFAs (5·41 ± 1·00 vs. 0·48 ± 0·20 mmol/l; P < 0·005) and significantly increased insulin resistance [glucose infusion rate (GIR) 6·02 ± 2·60 vs. 4·08 ± 2·15 mg/kg/min; P < 0·005]. After lipid and saline infusions no changes in 11,-HSD1 activity were found, neither by changes in cortisone acetate to cortisol conversion nor by differences in urinary free cortisol (UFF) or cortisone (UFE), 5,-tetrahydrocortisol (THF), 5,-THF, cortisone (THE), UFF/UFE and (5,-THF + THF)/THE ratios. Conclusions, We found no change in hepatic and whole-body 11,-HSD1 activity during acute FFA-induced insulin resistance. Further studies are necessary to clarify whether 11,-HSD1 in muscle and adipose tissue is influenced by FFAs and whether 11,-HSD1 is involved in other conditions of insulin resistance. [source] | ||||||||||||||||