Ovarian Steroidogenesis in the Proestrous Hamster

Abstract

In the proestrous hamster, in response to the LH surge, there is a dramatic and sustained increase in serum progesterone (P) and transitory increases in testosterone (T), estrone (E₁) and estradiol-17β (E₂). Ovarian steroidogenesis in the proestrous hamster was analyzed in detail by studying: 1) concentrations of these steroids in the whole ovary, antral follicles (AF) and the nonantral follicular portion of the ovary (NAO) at 1200 h (prior to the LH surge), 1500 h (during the LH surge) and 1800 h (after the LH surge); 2) in vitro steroidogenic production by the AF and NAO, as well as the whole ovary (removed before 1200 h, 1500 h and 1800 h and 3) in vitro effects of LH, FSH and P on steroidogenesis of ovaries removed before the LH surge and incubated for 2 h.