Hippocampal cholinergic blockade enhances hypothalamic-pituitary-adrenal responses to stress.
We examined the role of the hippocampal cholinergic system, which is known to mediate processes related to fear and anxiety, in the regulation of stress-induced hypothalamic-pituitary-adrenal (HPA) activity. Bilateral intra-hippocampal injections (30 microg per side) of the muscarinic antagonist Scopolamine augmented adrenocorticotropin and corticosterone responses to restraint without altering basal HPA activity compared to vehicle-treated animals. These results suggest that the hippocampal cholinergic system regulates stress-induced HPA activity and may serve to coordinate behavioral and neuroendocrine responses to stress.
Bhatnagar
S
S
Department of Physiology, University of California at San Francisco, 94143-0444, USA.
Costall
B
B
Smythe
J W
JW
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D002799:Cholinergic Fibers / Q000187:drug effects*; D003345:Corticosterone / Q000097:blood; D005239:Fear; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology*; D008845:Microinjections; D010276:Parasympatholytics / Q000494:pharmacology; D010913:Pituitary-Adrenal System / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012601:Scopolamine / Q000494:pharmacology; D013312:Stress, Physiological / Q000503:physiopathology*
D010276:Parasympatholytics; D000324:Adrenocorticotropic Hormone; D012601:Scopolamine; D003345:Corticosterone