Cell death and luteinization of ovarian granulosa cells

卵巢颗粒细胞的细胞死亡和黄素化

基本信息

批准号：
10671521
负责人：
ASAKAI Rei
金额：
$ 2.05万
依托单位：
Tokyo Medical and Dental University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

Most of ovarian follicles during development undergo cell death (it is called atresia), and thus it is important to elucidate the underlying mechanism. To gain insights into atresia, a cultured granulosa cell system in the presence of follicle stimulating hormone (FSH) plus luteinizing hormone (LH) in defined medium has been newly established, mimicking three stages of differentiation, maturation, as evaluated by the ability of progesterone secretion, and finally necrotic cell death. Recombinant FSH alone was found to be sufficient for inducing the three stages, whereas in the absence of FSH such stage changes did not occurred. The cell death was inhibited by the cyclooxygenase inhibitor indomethacin and cyclooxygenase 2 was detected immuno-histochemically only prior to cell death. Moreover, prostaglandin E2 was able to induce cell death only when it was added at the maturation stage, suggesting the role of prostaglandin synthesis as a death trigger. Investigation of the dying process revealed that cell death was effectively blocked by nifedipine, an inhibitor for Ca2+ channels and by two iron ion chelators presumably through inhibition of the Fenton reaction. These data provide the first evidence that FSH-primed prostaglandin synthesis in the maturation stage may be responsible for granulosa cell death during the atresia at antral stages.

大多数卵泡在发育过程中都会经历细胞死亡（称为闭锁），因此阐明其潜在机制非常重要。为了深入了解闭锁，新建立了在限定培养基中存在卵泡刺激素 (FSH) 和黄体生成素 (LH) 的情况下培养的颗粒细胞系统，模拟分化、成熟的三个阶段，通过黄体酮的能力进行评估分泌，最后坏死细胞死亡。发现单独的重组 FSH 足以诱导这三个阶段，而在没有 FSH 的情况下，不会发生这样的阶段变化。细胞死亡被环氧合酶抑制剂吲哚美辛抑制，并且仅在细胞死亡之前通过免疫组织化学方法检测到环氧合酶2。此外，只有在成熟阶段添加前列腺素E2才能诱导细胞死亡，这表明前列腺素合成具有死亡触发因素的作用。对死亡过程的研究表明，硝苯地平（Ca2+通道抑制剂）和两种铁离子螯合剂可能通过抑制芬顿反应有效地阻止了细胞死亡。这些数据提供了第一个证据，证明成熟阶段 FSH 引发的前列腺素合成可能是窦期闭锁期间颗粒细胞死亡的原因。