Effects of gonadotropin-releasing hormones, corticotropin-releasing hormone, and vasopressin on female sexual behavior

The effects of intracerebroventricular (icv) infusion of four neuropeptides on female sexual behavior were examined in the female musk shrew (Suncus m urinus). In the first experiment, (icv) infusion of 100 ng of the mammalian form of gonadotropin-releasing hormone (mGnRH) facilitated rapid display o f receptivity. Gonadotropin-releasing hormone-infused females had shorter l atencies to rump present and tail wag, compared with controls. In a second experiment, icy administration of the other form of GnRH present in musk sh rew brain, the chicken GnRH-II form, produced no changes in female behavior relative to the control condition. In Experiment 3, icy delivery of cortic otropin-releasing hormone (CRH) facilitated female sexual behavior, relativ e to vasopressin and controls. The females treated with CRH had shorter lat encies to display rump present, tail wag, and for the receipt of the first missed intromission compared with females in the other treatment groups. Va sopressin increased female scent marking relative to that of CRH-treated fe males. These data indicate that neurohormones of the hypothalamic-pituitary -gonadal and the hypothalamic-pituitary-adrenal axes can facilitate reprodu ctive behavior in S.murinus. (C) 2000 Academic Press.