Progesterone, Androstenedione, Testosterone, Estrone, and Estradiol Synthesis in Hamster Ovarian Follicle Cells

Abstract

Isolated granulosa cells and theca from proestrous hamsters alone and in recombination, were cultured in order to study steroidogenic capacity of this tissue. Cells from medium size antral follicles (100-300 mum diam.) and large preovulatory follicles (500 plus mum diam.) were used. Steroids were measured by radioimmunoassay. Cultures of cells derived from both sizes of follicles made significant amounts of progesterone for up to 6 days in tissue culture. The preparations from the medium sized antral follicles synthesized little or no estrogen. Of the cells harvested from the preovulatory follicles, the granulosa and theca made moderate amounts of estradiol-17beta while the recombined system made similar to 5 times the estradiol-17beta made by theca or granulosa alone. The results indicate that in the in vitro system used: 1) The hamster follicle cells are similar to other species in that they spontaneously luteinize in culture and secrete large amounts of progesterone, 2) Androgen accumulation is greatest in media from cultured theca of preovulatory follicle, 3) A synergism between theca and granulosa of the large preovulatory follicle exists to effect maximal estrogen synthesis, and 4) Estrogen synthesis is short-lived in vitro in contrast to continued progesterone production.

Inhibition of thecal androstenedione production by exogenous progesterone in the cyclic hamster

“…The present study confirms that the theca is a major site of androstenedione synthesis in the hamster follicle (Makris & Ryan, 1975) and that progesterone reduces circulating levels of oestradiol in the cyclic hamster (Greenwald, 1982). The acute decline in follicular oestradiol production induced by progesterone appears to be due to a lower circulating level of LH that induces a decline in thecal androstenedione production.…”

Hormonal regulation of preovulatory follicle maturation in the rat

“…An examination of the relationship between FSH-induced LH/hCG receptors and the steroidogenic capacity of granulosa cells of oestrogen-primed hypophysectomized rats showed that early antrum formation following treatment with FSH for 24 h was associated with marked increases in both steroidogenic potential and binding of 125I-labelled hCG in vitro (Hillier et al, 1978 (Baird & Fraser, 1975;Makris & Ryan, 1975). The classical experiments of Falck (1959) (Fortune & Armstrong, 1977 Granulosa cell suspensions were prepared from the ovaries of 27-day-old oestrogen-primed hypophysectomized rats injected with saline (9 g NaCl/1) or 100 µg oFSH (LER-1698) …”

Postovulatory steroidogenesis after ovulation induced by LH or FSH in hypophysectomized pro-oestrous hamsters

“…Antral follicles, in particular the granulosa cells, are the major sites of oestrogen synthesis in the hamster (Makris & Ryan, 1975 Armstrong & Papkoff, 1976;Erickson & Hsueh, 1978). Since LH treatment results in histological evidence of stimulation of theca interna cells and interstitial cells in hypophysectomized rats (Greep, Van Dyke & Chow, 1942;Lostroh & Johnson, 1966) and since these cells contain LH receptors (Zeleznik, Midgley & Reichert, 1974), it seems likely that in the present study these cells are responsible for the increased production of testosterone after LH treatment.…”

“…The CL of the sham-hypophysectomized hamsters contain appreciable amounts of oestradiol-17ß and testosterone ( (Makris & Ryan, 1975. In the presence of androstenedione or testosterone, the CL of the pregnant hamster produce large amounts of oestradiol-17ß during incubation for 2 h (A. J. Vomachka & G. S. Greenwald, unpublished).…”