GRANULOSA-THECAL CELL-INTERACTION IN OVARIAN STEROIDOGENESIS

1. 1. It is clear from all studies of follicles in many species that the theca under LH control favors androgen production and the granulosa stimulated by FSH favors aromatization. This is consonant with synergism of FSH and LH in follicle development and the synergism of the two cells in oestrogen production. 2. 2. While granulosa and theca from all species have a qualitatively similar production pattern, they differ quantitatively and the human deviates the most with more thecal aromatization and granulosa androgen production than other species. 3. 3. The spectrum of cell steroid production appears to change after luteinization, especially after the acquisition of LH receptors by the granulosa. 4. 4. While the theca may be the sole major source of preovulatory ovarian vein oestrogen in the primate, its limited aromatization in other species precludes this as an absolute phenomenon. 5. 5. Two-cell interaction must be viewed as a species variable dynamic process with changes occurring as each follicle develops during the ovarian cycle. © 1979.