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

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.