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HPA Axis Function (hpa axis + function)
Selected AbstractsPersonality pathology, depression and HPA axis functioningHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 4 2001I. Schweitzer Abstract Hypothalamic pituitary adrenal (HPA) axis functioning, as measured by the dexamethasone suppression test (DST), has been extensively investigated in major depressive disorder (MDD). Evaluating DST response in MDD patients while simultaneously considering clinically relevant personality disorders may further clarify the contribution of both personality pathology and HPA axis function to depressive symptoms. The present study measured personality pathology by administering the revised version of the Millon Clinical Multiaxial Inventory (MCMI-II) in a sample of 25 patients diagnosed with MDD. Analyses revealed that suppressors (n,=,19) scored significantly higher than non-suppressors (n,=,6) on six of the 13 MCMI-II personality disorder scales: Avoidant, Schizoid, Self-Defeating, Passive-Aggressive, Schizotypal and Borderline. Increased personality pathology was associated with normal suppression of cortisol following the DST. This suggests that suppression of the DST may be associated with depressive states linked with personality pathology while the more biologically based depression is associated with abnormal HPA pathophysiology. Copyright © 2001 John Wiley & Sons, Ltd. [source] Effects of Chronic Oestrogen Replacement on Stress-Induced Activation of Hypothalamic-Pituitary-Adrenal Axis Control PathwaysJOURNAL OF NEUROENDOCRINOLOGY, Issue 8 2000C. V. Dayas Abstract Oestrogen replacement therapy reportedly suppresses hypothalamic-pituitary-adrenal (HPA) axis responses to an emotional stressor in postmenopausal women. However, most studies in the rat suggest a facilitatory role for oestrogen in the control of HPA axis function. One explanation for this difference may be the regimen of oestrogen replacement: during oestrogen replacement therapy, oestrogen levels are low and constant whereas most animal studies examined the HPA axis response when oestrogen levels are rising. In the present study, we assessed HPA axis stress responses in mature ovariectomized rats after plasma oestrogen levels had been maintained at physiological levels for a prolonged period (25 or 100 pg/ml for 7 days). In the case of both an emotional stressor (noise) and a physical stressor (immune challenge by systemic interleukin-1, administration), oestrogen replacement suppressed stress-related Fos-like immunolabelling, in hypothalamic neuroendocrine cells and plasma adrenocorticotropin hormone responses. From the present data, and past reports, it appears unlikely that these effects of oestrogen are due to a direct action on corticotropin-releasing factor or oxytocin cells. Therefore, to obtain some indication of oestrogen's possible site(s) of action, Fos-like immunolabelling was mapped in the amygdala and in brainstem catecholamine groups, which are neuronal populations demonstrating substantial evidence of involvement in the generation of HPA axis stress responses. In the amygdala, oestrogen replacement suppressed central nucleus responses to immune challenge, but not to noise. Amongst catecholamine cells, oestrogen replacement was more effective against responses to noise than immune challenge, suppressing A1 and A2 (noradrenergic) and C2 (adrenergic) responses to noise, but only A1 responses to immune challenge. These data suggest that, as in postmenopausal women on oestrogen replacement therapy, chronic low-level oestrogen replacement can suppress HPA axis stress responses in the rat. Moreover, oestrogen appears to exert effects at multiple sites within putative HPA axis control pathways, even though most of the relevant neuronal populations do not contain genomic receptors for this gonadal steroid and the pattern of oestrogen action differs for an emotional vs a physical stressor. [source] Hypothalamic Function in Response to 2-Deoxy- d -Glucose in Long-Term Abstinent AlcoholicsALCOHOLISM, Issue 5 2001John C. Umhau Background: The body adapts to diverse stressful stimuli with a response characterized by activation of the hypothalamic-pituitary-adrenal (HPA) axis. Chronic alcohol consumption can cause changes in the function of this neuroendocrine system. Although many studies have examined this phenomenon in drinking and recently sober alcoholics, few studies have examined HPA axis function in long-term sober alcoholics. Methods: To characterize HPA axis function in long-term sober alcoholics, we used a challenge paradigm with 2-deoxy-d-glucose (2-DG). An infusion of 2-DG (a nonmetabolizable glucose analog) induces a well-characterized stress response. In a previous study, our laboratory found an exaggerated corticotropin and cortisol response in alcoholics abstinent 3 weeks; in this investigation we compared the effects of an infusion of 2-DG on 19 healthy volunteers and 20 community-living alcoholics who had been abstinent more than 6 months. Results: In contrast to the previous study, long-term sober alcoholics did not have an exaggerated corticotropin and cortisol response after 2-DG. Conclusions: Previously observed abnormalities in cortisol regulation in 3-week-sober alcoholics may be related to the acute effects of recent alcohol consumption and withdrawal. Future investigations into the metabolic function of alcoholics, particularly investigations involving the HPA system, should consider the possibility that normalization may not occur until long-term abstinence has been achieved. [source] HPA axis safety of fluticasone furoate nasal spray once daily in children with perennial allergic rhinitisPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2009Ita Tripathy The effects of intranasal corticosteroids (INSs) on the hypothalamic,pituitary,adrenal (HPA) axis should be assessed for any to be marketed INS. The objective of this study was to assess the effects of fluticasone furoate nasal spray (FFNS) on cortisol production (as a measure of HPA axis function) following 6 wk of treatment with FFNS 110 ,g once daily (QD) compared with placebo in pediatric patients with perennial allergic rhinitis (PAR). In this double-blind, parallel-group study, patients (n = 112) aged 2,11 yr with a 1-yr history of PAR (6 months for patients aged 2,3 yr) were randomized in a 1:1 ratio to either placebo or FFNS. Serum cortisol (SC) concentrations and urinary cortisol (UC) excretion were measured over a 24-h period at the randomization (baseline) and final treatment (week 6) visits for HPA axis evaluation in a domiciled environment (overnight in the clinic). Plasma samples were collected for FFNS at several time points over the 24 h after the final dose for pharmacokinetic analyses. FFNS was non-inferior to placebo with respect to change from baseline (expressed as a ratio) in 24-h SC weighted mean. The lower limit of the two-sided 95% confidence interval (CI) for the treatment ratio was greater than the pre-specified non-inferiority margin of 0.8 (treatment ratio = 0.97, 95% CI 0.88,1.07). UC excretion over 24 h at baseline and end of treatment was similar between treatment groups; no patients had 24-h excretion levels below normal range after 6 wk of treatment. Plasma concentrations of FFNS were generally non-quantifiable (<10 pg/ml). Results of the current study indicate that FFNS 110 ,g QD has no significant effect on HPA axis function in 2- to 11-yr-old pediatric patients with PAR. [source] Prenatal synthetic glucocorticoid exposure alters hypothalamic,pituitary,adrenal regulation and pregnancy outcomes in mature female guinea pigsTHE JOURNAL OF PHYSIOLOGY, Issue 5 2010Elizabeth Dunn Preterm delivery occurs in approximately 10% of all pregnancies. Prenatal exposure to synthetic glucocorticoids (sGCs) reduces the incidence of respiratory distress syndrome (RDS) in these babies. Therefore, administration of multiple courses of sGCs became common practice. Animal and human studies have demonstrated that multiple courses of sGCs can have long-term effects. While the majority of animal studies have been undertaken in male offspring, it is emerging that there are profound sex differences in the consequences of prenatal sGC exposure. To our knowledge, no studies have determined the effects of prenatal sGC exposure on hypothalamic,pituitary,adrenal (HPA) axis function in female offspring while accounting for reproductive cycle status, or determined if there are effects on pregnancy parameters. Pregnant guinea pigs were administered three courses of betamethasone (Beta), dexamethasone (Dex) or vehicle on gestational days 40/41, 50/51 and 60/61. In adulthood (age range: postnatal days 126,165), basal and activated HPA axis function were assessed at various stages of the reproductive cycle. The female offspring were then mated and underwent an undisturbed pregnancy. Females were killed in the luteal phase of the reproductive cycle following litter weaning, and molecular analysis undertaken. In the luteal phase, Beta-exposed females exhibited significantly lower basal salivary cortisol levels (P < 0.05). Dex-exposed females also exhibited significantly lower basal salivary cortisol levels during the luteal phase (P < 0.05), but increased basal salivary cortisol levels during the ostrous phase (P < 0.01). The Beta-exposed females exhibited increased glucocorticoid receptor (GR) mRNA expression in the CA1/2 region of the hippocampus (P < 0.05) and MC2R mRNA in the adrenal cortex (P < 0.05). The Dex-exposed animals exhibited higher hippocampal GR and mineralocorticoid receptor (MR) mRNA levels (P < 0.05). Beta-exposed females showed reduced fecundity (P < 0.05). In Dex-exposed females there was a lower male to female sex ratio. In conclusion, prenatal sGC exposure affects HPA axis activity, in a cycle-dependent manner, and long-term reproductive success. The clinical implications of the findings on endocrine function and pregnancy in females are profound and further follow-up is warranted in human cohorts. Furthermore, we have shown there are considerable difference in phenotypes between the Beta- and Dex-exposed females and the specific endocrine and maternal outcome is contingent on the specific sGCs administered during pregnancy. [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] Abnormalities of the HPA axis in affective disorders: clinical subtypes and potential treatmentsACTA NEUROPSYCHIATRICA, Issue 5 2006Richard J. Porter Background:, New evidence is emerging regarding abnormalities of hypothalamic-pituitary-adrenal (HPA) axis function in subtypes of affective disorders. Adverse effects of HPA axis dysregulation may include dysfunction of monoaminergic transmitter systems, cognitive impairment and peripheral effects. Newer treatments specifically targeting the HPA axis are being developed. Objective:, To review these developments focusing particularly on the glucocorticoid receptor (GR) antagonist mifepristone. Method:, A selective review of the literature. Results:, The function of GRs is increasingly being defined. The role of corticotrophin-releasing hormone (CRH) and dehydroepiandrosterone (DHEA) in the brain is also increasingly understood. HPA axis function is particularly likely to be abnormal in psychotic depression and bipolar disorder, and it is in these conditions that trials of the GR antagonist mifepristone are being focused. CRH antagonists and DHEA are also being investigated as potential treatments. Conclusion:, Initial studies of mifepristone and other HPA-axis-targeting agents in psychotic depression and bipolar disorder are encouraging and confirmatory studies are awaited. [source] | ||||||||||