The effects of chronic glucocorticoid excess, adrenalectomy and stress on neuropeptide Y in individual rat hypothalamic nuclei

Details

Serval ID
serval:BIB_1A6378319521
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
The effects of chronic glucocorticoid excess, adrenalectomy and stress on neuropeptide Y in individual rat hypothalamic nuclei
Journal
Neuropeptides
Author(s)
Pralong  F. P., Corder  R., Gaillard  R. C.
ISSN
0143-4179 (Print)
Publication state
Published
Issued date
10/1993
Volume
25
Number
4
Pages
223-31
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Oct
Abstract
Several lines of evidence indicate a role for neuropeptide Y (NPY) in the modulation of the corticotroph axis. In two separate studies reported here, the concentrations of NPY and noradrenaline (NA), as well as corticotropin-releasing factor (CRF) and arginine vasopressin (AVP), were measured in extracts of individual rat hypothalamic nuclei after various manipulations producing either a state of chronic glucocorticoid excess or depletion, and also following repeated restraint stress. Alterations induced in the activity of hypothalamic neurones were inferred from the respective changes in these concentrations. 12 days after bilateral adrenalectomy (ADX), NPY levels were decreased by 24% in the arcuate nucleus (ARC) and 23% in the paraventricular nucleus (PVN, p < 0.05 vs controls). Forced immobilization of the animals for 4 h each day for 9 consecutive days (repeated stress) also decreased NPY content of the ARC by 25% (p < 0.01 vs controls), an effect blocked by the administration of glucocorticoids. NA levels in both hypothalamic nuclei were unaffected by repeated stress or ADX. Administration of glucocorticoids in the first of these studies induced decreases in NA levels by 15% and 25% in the ARC and PVN respectively (p < 0.05 vs controls). However, in subsequent experiments no significant effect of glucocorticoids on NA was observed. Our results demonstrate that the activity of the hypothalamic NPY-ergic neurones is modulated by glucocorticoids and by chronic stress. They also suggest that brainstem catecholaminergic and hypothalamic NPY-ergic neurones are differentially affected by altered glucocorticoid concentrations or by chronic stress, possibly in a stimulus-specific way.
Keywords
*Adrenalectomy Adrenocorticotropic Hormone/metabolism Animals Arcuate Nucleus/metabolism Arginine Vasopressin/metabolism Betamethasone/pharmacology Corticosterone/blood Corticotropin-Releasing Hormone/metabolism Glucocorticoids/administration & dosage/*pharmacology Hypothalamus/*metabolism Male Neuropeptide Y/*metabolism Norepinephrine/metabolism Paraventricular Hypothalamic Nucleus/metabolism Pituitary Gland/metabolism Rats Rats, Wistar Stress/*metabolism
Pubmed
Web of science
Create date
25/01/2008 16:26
Last modification date
20/08/2019 12:51
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