Study on the Mechanism of Granulosa Cell Differentiation

人卵泡颗粒细胞系的建立人卵泡颗粒细胞的寿命很短。我们将SV40DNA、Ha-Ras基因和p53基因三次导入原代细胞，建立了新的颗粒细胞系。这些稳定的细胞系增殖迅速，并显示出类固醇合成活性。CAMP刺激孕酮的产生。将生长温度从37℃改变到32℃会导致程序性细胞死亡。新建立的颗粒细胞系可作为研究永生化人颗粒细胞诱导类固醇合成的分子和细胞机制的有用工具。膜细胞对颗粒细胞凋亡的影响利用颗粒细胞和膜细胞维持在胶原膜相反表面的共培养系统，研究了膜细胞对颗粒细胞凋亡的影响。母鸡卵泡膜细胞刺激母鸡颗粒细胞凋亡。然而，这样的…从牛卵巢采集卵泡细胞，未检测到更多的膜细胞作用。膜细胞对颗粒细胞分化的影响研究了膜细胞在颗粒细胞激素产生活动中的可能作用。卵泡膜细胞减少卵泡发育早期颗粒细胞的雌二醇、抑制素和孕酮的产生，而在卵泡发育后期增加颗粒细胞的雌二醇、抑制素和孕酮的产生。这些结果表明，卵泡膜细胞在卵泡发育过程中对颗粒细胞的分化起着重要的调控作用。雄烯二酮和雌二醇对与膜细胞共同培养的颗粒细胞减数分裂抑制活性的影响本研究探讨了卵泡液中雄烯二酮和雌二醇对牛颗粒细胞减数分裂抑制活性的影响。本研究结果表明，雄烯二酮对颗粒细胞的减数分裂抑制活性具有剂量依赖性，生长卵泡液水平的雄烯二酮可增强颗粒细胞的减数分裂抑制活性，而闭锁卵泡水平的雄烯二酮则抑制颗粒细胞的减数分裂抑制活性。雌二醇没有雄烯二酮那样的作用。较少

Establishment of Steroidogenic Granulosa Cell Lines Originating from WomenThe life span of granulosa cells obtained from human ovarian follicle is very short. We established new granulosa cell lines by triple transfection of primary cells with SV40 DNA,Ha-RAS gene and p53 gene. These stable cell lines proliferated rapidly and showed steroidogenic activity. cAMP stimulate progesterone production. Shifting the temperature of growth from 37C to 32C induced programd cell death. This newly established granulosa cell lines can serve as a useful tool for the study of the molecular and cellular mechanisms of inducible steroidogenesis in immortalized human granulosa cells.Effects of Thecal Cells on Apoptosis of Granulosa cellsUsing the co-culture system in which granulosa and thecal cells were maintained on the opposite surface of a collagen membrane, effects of thecal cells on apoptosis of granulosa cells was investigated. Hen theca cells stimulated hen granulosa cell apoptosis. However, such … More effect of theca cells was not detected when follicular cells were collected from bovine ovaries.Effects of Thecal Cells on Granulosa Cell DifferentiationThe possible role of thecal cells in the control of the hormonal producing activity of granulosa cells was investigated. Thecal cells reduced estradiol, inhibin and progesterone production by granulosa cells from early stage of follicular development, while augmented those by cells at late developmental stage. These results demonstrate that the thecal cells play an important role in the control of granulosa cell differentiation during ovarian follicular development.Effects of Androstenedione and Estradiol on the Meiosis-Arresting Activity of the Granulosa Cells Cultured Together with Thecal CellsThe present study explored how the meiosis-arresting activity of bovine granulosa cells is controlled by androstenedione and estradiol of the follicular fluid. This study showed that androstenedione controls the meiosis-arresting activity of the granulosa cells biphasically depending on its dose ; growing follicle fluid level of androstenedione augments the meiosis-arresting activity of granulosa cells, while atretic follicle level of androstenedione suppresses it. Estradiol does not such effect as that of androstenedione. Less