转铁蛋白抑制FSH刺激大鼠卵泡颗粒细胞分化的细胞内主要机制

The main intracellular mechanism of inhibitory effect of Transferrin on FSH -induced differentiation of rat granulosa cells

前期的研究已经证实了转铁蛋白(TRF)能抑制FSH诱导的抑制素、雌二醇和孕酮的产生以及芳香化酶活性。本实验用已烯雌酚处理后分离的大鼠卵泡颗粒细胞的体外培养方法,进一步观察TRF对FSH、霍乱毒素(cholera toxin,CT)及Forskolin诱导的cAMP、雌二醇及孕酮产生的影响。结果:TRF抑制了FSH诱导的cAMP、雌二醇及孕酮产生TRF能抑制CT及Forskolin诱导的雌二醇产生,但不影响这些因子刺激cAMP和孕酮生成。说明TRF抑制FSH对大鼠卵泡颗粒细胞功能性分化刺激作用的主要细胞内机制是通过减少cAMP生成而介导的,但还有cAMP以外的作用部位。

It has been demonstrated that transferrin (TRF) was able to attenuate FSH -induced production of inhibin,estradiol and progesterone,and aromatase activity in rat granulosa cells (GO. In this experiment, the effect of TRF on FSH -, cholera toxin (CT)-and foskolin-induced production of cAMP, together with the output of estradiol and progesterone, were investigated using GC isolated from diethylstilbestrol treated rats. The results showed that TRF inhibited FSH - induced production of cAMP, which was in accordance with the reduced production of estradiol and progestrone. TRF also inhibited CT-and forskolin-induced production of estradiol, but the stimulation of cAMP and progesterone production by these two agents was not affected. Combining these results together with previous studies, we conclude that the mechanism of TRF to attenuate FSH - induced differentiation of rat granulosa cells mainly involved the inhibition of cAMP stimulation, but mediates other than cAMP also exist.