The ovarian control of the hypophysial gonadotrophic function.

Abstract

Those aspects of ovarian function which are thought to be involved in the regulation of pituitary gonadotrophic activity have been experimentally dissociated: (1) hormone production without normal 'competitive consumption' of gonadotrophin (in an ovarian fragment in situ), and (2) 'consumption' of gonadotrophin unaccompanied by hormone activity (in an intrasplenic graft). The abnormal behaviour displayed by an ovarian remnant maintained alone in the body for long experimental periods and manifested by cyst formation of the rete ovarii (method II, see Text-fig. 1) is not counteracted by an intrasplenic ovarian graft allowed to act only by virtue of its 'consumption' of gonadotrophin (method V). On the other hand, the ovarian fragment, even when not showing the same degree of follicular development and luteinization as an entire ovary in situ, counteracts to a very considerable degree the production of haemorrhagic follicles in the intrasplenic graft (methods IV and V). Therefore, the ovarian remnant is able to exert some control over the anterior pituitary, presumably by producing oestrogen. In the presence of an intrasplenic graft luteinization is less pronounced in an ovarian remnant (method V) than in the entire ovary retained in situ (method VI). Correspondingly, luteinization in the intrasplenic graft is more pronounced in the first than in the second case. While 'competitive consumption' of gonadotrophin is probably a significant factor in follicular development and luteinization, it has not been proved conclusively that it also controls production and release of the pituitary gonadotrophic hormones.