DIFFERENTIAL EXPRESSION OF VASOPRESSIN RECEPTOR-BINDING IN THE HYPOTHALAMUS DURING LACTATION IN GOLDEN-HAMSTERS

Vasopressin (AVP) receptor binding within hypothalamic sites was compa red between cycling and lactating female golden hamsters. The density of AVP receptor bindig was analyzed by quantitative autoradiography wi thin the ventrolateral hypothalamus and dorsomedial hypothalamic nucle us. Lactation was correlated with a disappearance of AVP receptor bind ing within the ventrolateral hypothalamus. In contrast, lactation was associated with a two- to three-fold increase in the density of AVP re ceptor binding within the dorsomedial hypothalamic nucleus. These resu lts suggest that AW receptor binding within the ventrolateral hypothal amus is responsive to gonadal hormones in female golden hamsters. Howe ver, the increase in binding observed within the dorsomedial hypothala mus may be related to other neurobiological changes associated with la ctation.