Corticotropin-releasing factor is a potent inhibitor of sexual receptivity in the female rat

Corticotropin-releasing factor (CRF), the recently characterized and synthesized 41-amino acid polypeptide 1,2 isolated from ovine hypothalami, has been shown to be a potent stimulator of adenohypophyseal β -endorphin and corticotropin (ACTH) secretion both in vitro 2,6 and in vivo 2,4,7,8 . In common with other regulatory peptides, CRF has also been demonstrated to possess extra-hypophysiotropic roles. Indeed, intracerebroventricularly (i.c.v.) administered CRF elicits several endocrine and behavioural responses compatible with the concept that this peptide could be a key signal in coordinating the organism's endocrine and behavioural responses to stressful and other adaptive stimuli 8–14 . We now provide the first evidence for neurally placed CRF in the control of a specific hormone-dependent behavioural response and unequivocally demonstrate an extremely potent suppressive effect of CRF on sexual behaviour in the female rat when microinfused into the arcuate–ventromedial area of the hypothalamus (ARC–VMH) and the mesencephalic central grey (MCG).