Social stress inhibits the nitric oxide effect on the corticotropin-releasing hormone- but not vasopressin-induced pituitary-adrenocortical responsiveness.
Putative involvement of endogenous nitric oxide (NO) in the corticotropin-releasing hormone (CRH, 1 microg/kg i.p.)- and vasopressin (AVP, 5 microg/kg i.p.)-induced ACTH and corticosterone secretion was investigated in both non-stressed and crowded rats. The NO synthase blocker Nomega-nitro-l-arginine (l-NNA, 2 mg/kg i.p. ) significantly augmented the AVP-induced ACTH and corticosterone secretion in control and stressed rats, but it increased the CRH-induced ACTH response only in control rats. Crowding stress did not affect the l-NNA evoked increase in AVP-induced hormone responses, but it abolished the CRH-induced ACTH response.
Bugajski
J
J
Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, 12 Sm&ecedil;tna Street, 31-343, Kraków, Poland. bugajski@if-pan.krakow.pl
Gadek-Michalska
A
A
Borycz
J
J
Głód
R
R
D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism*; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008297:Male; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D019335:Nitroarginine / Q000494:pharmacology; D010913:Pituitary-Adrenal System / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012636:Secretory Rate; D012931:Social Environment; D013315:Stress, Psychological / Q000503:physiopathology*
D004791:Enzyme Inhibitors; D001127:Arginine Vasopressin; D019335:Nitroarginine; D009569:Nitric Oxide; D003346:Corticotropin-Releasing Hormone; D019001:Nitric Oxide Synthase