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 growth factor (bFGF) on gonadotropin-dependent estradiol and progesterone production in cultured rat immature and FSH-primed granulosa cells. Treatment with bFGF alone did not affect the biosynthesis of estradiol and progesterone in immature and FSH-primed granulosa cells. Basic FGF significantly inhibited FSH-induced estradiol and progesterone production in both immature and FSH-primed granulosa cells. In contrast, bFGF exerted a significant stimulatory effect on LH-induced estradiol and progesterone production in FSH-primed granulosa cells. Our finding that bFGF exerts opposite effects on gonadotropin-dependent steroidogenesis suggests that bFGF may play important paracrine and/or autocrine roles in the process of follicular development, ovulation, and subsequent luteinization.