Study for Effects of Ovarian Thecal Cells on Meiosis-Arresting Activity and Differentiation of Granulosa Cells

我们已经成功地开发了一种共培养系统，其中卵巢颗粒和鞘细胞生长在胶原膜的两侧。利用这种共培养系统，我们之前已经证明了两种滤泡细胞类型相互调节其增殖，形态，结构和功能。在本研究的第一个系列中，我们使用这种培养系统研究了颗粒-卵泡细胞通讯对卵母细胞成熟的影响。牛卵丘-卵母细胞复合物与颗粒细胞孵育，有或没有卵泡细胞。观察生发囊破裂的时间过程。与颗粒细胞和卵泡细胞一起培养时，与颗粒细胞单独培养相比，生发囊泡的破裂明显延迟。当卵母细胞复合物与卵泡刺激素或低剂量雄烯二酮处理的颗粒细胞与卵泡细胞一起孵育时，破坏进一步延迟。而大剂量雄烯二酮或雌二醇对颗粒细胞生发囊泡破裂无明显影响。在第二系列研究中，研究了鞘细胞对体外发育早、中、晚期卵泡颗粒细胞的激素分泌活性和超微结构的影响。在卵泡发育早期，囊膜细胞分别减少颗粒细胞分泌激素，而在卵泡发育后期，囊膜细胞则增加颗粒细胞分泌激素。与鞘细胞共培养的颗粒细胞的形态学分析显示，小卵泡细胞的溶酶体聚集减少，内质网和线粒体收缩，但与单独培养的细胞相比，成熟卵泡细胞的这些细胞分化特征增强。这些结果表明，卵巢卵泡发育过程中，鞘细胞分泌抑制未成熟颗粒细胞分化而促进成熟颗粒细胞分化的因子，提示鞘细胞在控制颗粒细胞分化中起重要作用。少

We have successfully developed a co-culture system in which ovarian granulosa and thecal cells are grown on opposite sides of a collagen membrane. Using this co-culture system, we have previously demonstrated that the two follicular cell types reciprocally modulate their proliferation, morphology, structure and function.In the first series of the study, we have examined the effect of granulosa-theca cell communication on oocyte maturation using this culture system. Bovine cumulus-oocyte complexes were incubated with granulosaa cells, with or without theca cells. The time course of germinal vesicle breakdown was assessed. When cultured with granulosa and theca cells, germinal vesicle breakdown was significantly delayd compared when cultured with granulosa cells alone. Breakdown was further delayd when cumulus-oocyte complexes were incubated with FSH- or low-dose of androstenedione-treated granulosa cells with theca cells. While, such effects on germinal vesicle breakdown was not detecte … More d when granulosa cells were incubated with high dose of androstenedione or estradiol.In the second series of the study, the influence of thecal cells on the hormonal producing activity as well as the ultrastructure of granulosa cells from early-, mid-and late-developmental stage follicles in vitro was investigeted. Thecal cells reduced hormonal production by granulosa cells from early stage of follicular development, respectively, while augmented that by cells at late developmental stage. Morphological analysis of granulosa cells co-cultured with thecal cells shows a decrease in the clustering of lysosomes, shrinkage of endoplasmic reticulum and mitochondria of cells from small follicles but an enhancement of these cytodifferentiative features in cells from mature follicles when compared to the cells cultured alone. These results demonstrate that the thecal cells secrete factor (s) which inhibits the differentiation of the immature granulosa cells while promoting that of the matured ones and suggest that the thecal cells play an important role in the control of granulosa cell differentiation during ovarian follicular development. Less