OPPOSITE EFFECTS OF BASIC FIBROBLAST GROWTH-FACTOR ON GONADOTROPIN-STIMULATED STEROIDOGENESIS IN RAT GRANULOSA-CELLS

In the present study, we examined the effect of basic fibroblast growt h factor (bFGF) on gonadotropin-dependent estradiol and progesterone p roduction in cultured rat immature and FSH-primed granulosa cells. Tre atment with bFGF alone did not affect the biosynthesis of estradiol an d progesterone in immature and FSH-primed granulosa cells. Basic FGF s ignificantly inhibited FSH-induced estradiol and progesterone producti on in both immature and FSH-primed granulosa cells. In contrast, bFGF exerted a significant stimulatory effect on LH-induced estradiol and p rogesterone production in FSH-primed granulosa cells. Our finding that bFGF exerts opposite effects on gonadotropin-dependent steroidogenesi s suggests that bFGF may play important paracrine and/or autocrine rol es in the process of follicular development, ovulation, and subsequent luteinization.