大鼠卵巢颗粒细胞IGF—I,TGFβ,Fas—L表达与卵泡闭锁发生？…

为研究ＩＧＦ－Ｉ，ＴＧＦβ和Ｆａｓ－Ｌ在维持卵泡颗粒细胞存活和介导颗粒细胞凋亡中的作用。探讨卵泡闭锁的局部分子机理，将ＳＤ大鼠卵巢石蜡切片，用ＴＵＮＥＬ法和ＰＣＮ免疫组地区别闭锁和生长卵泡，用免疫组分法标记言之有理三种因子以及它们的膜受体在卵泡内的表达，结果显示，无腔和有腔生长卵泡内大多数颗国ＰＣＮＡ阳性，早期有腔闭锁卵泡有５个以上颗粒细胞被衍标记，部分颗粒细胞为ＰＣＮＡ阳性；晚期有腔闭锁卵泡剩余

The expression of IGF-I, TGF beta and Fas-L in granulosa cells of ovarian follicle with relation to the onset of atresia in rats]

This study was designed to investigate the effects of IGF-I, TGF beta and Fas-L on the sustaining of granulosa cells of ovarian follicle and the modulation of apoptosis of those cells, and to understand the molecular mechanisms of ovarian follicle atresia. Paraffin-embedded sections of SD rat ovary were made. Both TUNEL method and PCNA immunohistochemistry were employed to recognize atretic and healthy follicles. The expression of IGF-I, TGF beta, Fas-L and their receptors was displayed by immunostaining. The results showed that most of the granulosa cells within the healthy preantral and antral follicles were PCNA(+). At the early stage of atretic antral follicle, more than 5 granulosa cells were labelled by TUNEL method, and some granulosa cells were PCNA(+). At the late stage of atretic antral follicle, were labelled by TUNEL method. The immunoreactive products of IGF-I, IGF-IR, TGF beta, TGF beta R, Fas and Fas-L could be seen in the granulosa cells of healthy antral follicles. But, Granulosa cells were only TGF beta, TGF beta R and Fas immunopositive in all atretic antral follicles. In conclusion, combination of TUNEL method and PCNA immunochemistry is of benefit for distinguishing atretic follicles from healthy follicles. IGF-I might play an important role in stimulating proliferation of the granulosa cells and sustaining them. The lower expression or disappearance of IGF-I in the antral follicle might cause the onset of atresia. TGF beta, Fas-L and Fas might mediate apoptosis of the granulosa cells in antral follicles, causing follicle atresia. But, their effects of mediation could be inhibited as IGF-I exists in the follicles.