Activating and 'anxiogenic' effects of corticotropin releasing factor are not inhibited by blockade of the pituitary-adrenal system with dexamethasone.
Central administration of corticotropin releasing factor (CRF) in rats produces pituitary-adrenal activation and a variety of "anxiogenic-like" effects. The present study was designed to explore the contribution of the peripheral pituitary-adrenocortical axis in mediating these CRF responses. Intraventricularly administered CRF produced suppression of responding in the conflict test and a marked locomotor activation. Neither behavioral effect was altered by the prior administration of dexamethasone in a dose that blocked pituitary-adrenal activation to CRF. These results support the hypothesis that behavioral effects of CRF are mediated by its action at central sites and not via an action on the pituitary-adrenocortical system.
D000818:Animals; D001007:Anxiety / Q000187:drug effects*; D001921:Brain / Q000502:physiology*; D003220:Conflict, Psychological; D003345:Corticosterone / Q000097:blood; D003346:Corticotropin-Releasing Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D003907:Dexamethasone / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D010913:Pituitary-Adrenal System / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains
D003907:Dexamethasone; D003346:Corticotropin-Releasing Hormone; D003345:Corticosterone