Photoperiodic regulation of prolactin release in male hamsters with hypothalamic knife cuts.


Horizontal knife cuts placed dorsal to the paraventricular nucleus (PVN) of the hypothalamus prevent testicular regression in hamsters kept in short days. We examined the effects of these cuts on the photoperiodic modulation of the postcastration rise in gonadotropins, as well as on the release of prolactin in castrated and gonadally intact animals. The… (More)