Article date: 1986/1/1
PubMed ID: 2950977
Journal name: Comptes rendus des seances de la Societe de biologie et de ses filiales (ISSN: 0037-9026)
The thalamic pigeon was taken as a model to investigate mechanisms of adaptation to chronic intermittent stress. Muscimol was infused into the 3rd ventricle at the rate of 0.25 microgram.hr-1 by means of an osmotic minipump. In controls, pumps were filled in with saline. Animals were placed under constant light regimen and electrical foot shocks were delivered, thrice a day, at fixed time interval following a short dark period (3 min). In controls, adaptation of the adrenocortical response to chronic intermittent stress was achieved within 7 days, including both attenuation of the post-stress hypercorticosteronemia and occurrence of a pre-stress conditioned peak of corticosterone. The anticipating conditioned constituent subsisted in muscimol treated animals whereas no attenuation of the post-stress peak could be detected. GABAergic chronic treatment also resulted in decreased basal plasma corticosterone levels. In controls, extinction of the conditioned endocrine response was not obtained after conditioning stimulus (dark period) was presented alone for 2 weeks.
Author List: Ramade F, Baylé J D
Publication Types: English Abstract; Journal Article
Substances mentioned in the article: Muscimol; gamma-Aminobutyric Acid; Corticosterone;
Mesh terms: Animals; Columbidae; Conditioning (Psychology); Corticosterone/secretion; Electroshock; Muscimol/pharmacology; Stereotaxic Techniques; Stress, Physiological/physiopathology; Thalamus/drug effects; Time Factors; gamma-Aminobutyric Acid/physiology;