In Vitroandin VivoStimulation of the Release of Luteinizing Hormone

Abstract

The in vitro pituitary incubation system of Saffran and Schally was modified for the study of stimulation of luteinizing hormone (LH) secretion. The modification consisted of the use of chronically ovariectomized and estrogen progesterone-treated rats. The basic rate of LH secretion in vitro was established. Preparations of luteinizing hormone-releasing factor (LRF), of bovine and ovine origin, were shown to effect significant stimulation of LH release, in vitro. These preparations were also active in vivo in depleting ovarian ascorbic acid in immature rats pretreated with gonadotropins and in increasing plasma LH levels in chronically ovariectomized, estrogen progesteronetreated rats. Thus, the results of the in vitro experiments seem to show agreement with those from the in vivo studies. (Endocrinology75: 312, 1964)