Role of endogenous corticotropin-releasing factor in mediation of neuroendocrine and behavioral responses to cholecystokinin octapeptide sulfate ester in rats.
The possible involvement of endogenous corticotropin-releasing factor (CRF) in the anxiogenic and pituitary-adrenal-axis-activating effects of cholecystokinin octapeptide sulfate ester (CCK 8) was investigated in rats. Intracerebroventricularly (i.c.v.) administered CCK 8 induced an anxiogenic response in an elevated plus-maze test, and enhanced the plasma corticosterone level. Pretreatment with different dilutions (1:10, 1:20 and 1:100, i.c.v.) of CRF antiserum and different doses of a CRF receptor antagonist, alpha-helical CRF (ahCRF, 0.001-1.0 microgram, i.c.v.) prevented the anxiogenic response to CCK 8 in a dose-dependent manner. None of the doses of CRF antiserum or ahCRF alone produced any alteration in either the elevated plus-maze paradigm or corticosterone level in saline-treated control rats. The results strongly suggest that the anxiogenic and hypothalamo-pituitary-adrenal-activating effects of CCK 8 are mediated via CRF.
Biró
E
E
Department of Pathophysiology, Albert Szent-Györgyi Medical University, Szeged, Hungary.
Sarnyai
Z
Z
Penke
B
B
Szabó
G
G
Telegdy
G
G
D000818:Animals; D001007:Anxiety; D001522:Behavior, Animal / Q000187:drug effects*; D003345:Corticosterone / Q000097:blood*; D003346:Corticotropin-Releasing Hormone / Q000276:immunology / Q000502:physiology*; D007116:Immunization, Passive; D007276:Injections, Intraventricular; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012844:Sincalide / Q000008:administration & dosage / Q000494:pharmacology*
D003346:Corticotropin-Releasing Hormone; D012844:Sincalide; D003345:Corticosterone