Evidence that arginine vasotocin inhibits human chorionic gonadotropin and cyclic adenosine 3',5' monophosphate stimulated ovarian steroidogenesis

Abstract

SummaryA study of the ovary as a site of action of arginine vasotocin, a nonapeptide synthesized in the pineal gland of vertebrates, was conducted in the rat. Progesterone production stimulated by either human Chorionic Gonadotropin or 8Br-cyclic Adenosine 3',5' Monophosphate was significantly reduced in rats prepreated with arginine vasotocin. The affinity and receptor number for human chorionic gonadotropin were uneffected by pretreatment with arginine vasotocin. These results suggest that the antigonadotropic action attributed to arginine vasotocin may be due to an inhibition of ovarian steroidogenesis at a point distal to cyclic Adenosine 3',5' Monophosphate formation.