Faculty Collaboration Database

Corticosterone inhibition of osmotically stimulated vasopressin from hypothalamic-neurohypophysial explants. Am J Physiol 1997 Jan;272(1 Pt 2):R158-62

Date

01/01/1997

Pubmed ID

9039004

DOI

10.1152/ajpregu.1997.272.1.R158

Scopus ID

2-s2.0-0031022713 (requires institutional sign-in at Scopus site)   34 Citations

Abstract

Glucocorticoids inhibit and glucocorticoid deficiency increases vasopressin (AVP) release in vivo. To determine whether the effect of glucocorticoids is hypothalamic and mediated via a glucocorticoid receptor, explants of the hypothalamic-neurohypophysial system were used to measure AVP release during agonist and antagonist exposure. Explants from adult rats, which contained AVP neurons of the supraoptic nucleus with axonal projections terminating in the neural lobe but excluded the paraventricular nucleus, were perifused with an osmotic stimulus (increase of 5 mosmol/h over 6 h) in the absence or presence of corticosterone (100 micrograms/dl) or with corticosterone (100 micrograms/dl) in the absence or presence of the glucocorticoid antagonist RU-486 (10 microM). AVP release was not increased during osmotic stimulation in the presence of corticosterone (Cort) and was 20-30% lower than osmotically stimulated release observed in the absence of Cort. RU-486 reversed the inhibitory effect of corticosterone on AVP release. No changes in AVP mRNA content were detected. These results suggest that Cort inhibits osmotically stimulated AVP release by a direct effect within the hypothalamus and/or neurohypophysis. This effect is mediated by the glucocorticoid receptor through either genomic or nongenomic mechanisms.

Author List

Papanek PE, Sladek CD, Raff H

Authors

Paula Papanek PhD, MPT, LAT, FACSM Associate Professor & Director of Exercise Science in the Exercise Science & Physical Therapy department at Marquette University
Hershel Raff PhD Professor in the Academic Affairs department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Arginine Vasopressin
Corticosterone
Hormone Antagonists
Hypothalamo-Hypophyseal System
Male
Mifepristone
Osmosis
Pituitary Gland, Posterior
RNA, Messenger
Rats
Rats, Sprague-Dawley