GROWTH FACTORS IN FOLLICULAR DEVELOPMENT

颗粒细胞功能障碍导致卵泡闭锁，卵母细胞 退化、不育和各种生理功能的损害 依赖于卵巢类固醇的过程。 编写本 这项提议旨在深入了解复杂的细胞和分子 促性腺激素调节卵泡发生的一般机制 尤其是颗粒细胞的功能。 因为传统颗粒 细胞培养导致卵泡结构的丧失和 细胞功能，我们已经开发了一种替代方法来研究 卵泡功能通过使用分离的完整腔前卵泡从 仓鼠卵巢及其体外长期培养体系 发展 这项技术开辟了一个全新的研究领域 直接影响卵泡细胞增殖的生理生化 在它们的原生毛囊微环境中。 我们已经确定 这些培养物中的滤泡细胞合成cAMP和类固醇， 对促性腺激素反应增殖;表达促性腺激素受体， 以及独特的卵泡蛋白。 我们观察到促有丝分裂作用 FSH是通过EGF来分泌的。 放射免疫测定数据、蛋白质印迹和 免疫沉淀研究表明仓鼠卵巢既有EGF， TGF β 1和β 2样蛋白，以及EGF受体。 但 卵泡发育过程中的细胞和分子变化， 生长因子在这些过程中的作用仍有待确定。 我 卵泡细胞促性腺激素和类固醇调节假说 增殖和分化依赖于细胞膜的关键调节， 卵巢生长因子的活性（例如，EGF和TGF-β）及其 受体。 这一过程的中断导致颗粒细胞功能障碍， 细胞和不育。 本研究将集中在一个重要的 问题：（1）促性腺激素是否通过调节 卵巢EGF和TGF-β（β 1和β 2）的活动？ 这项研究将 包括（1）生长因子表达免疫组织化学分析， 它们在体内和体外卵泡发育期间的激素控制; (2)生长因子对卵泡生长影响的生物化学分析， 类固醇生成，和（3）免疫组织化学和生化评估 EGF-受体在卵泡发育的激素控制。 完整卵巢中促性腺激素作用途径的鉴定 卵泡将大大增加我们对人类 卵泡发生机制。

Malfunction of granulosa cells results in follicular atresia, oocyte degeneration, sterility and impairment of a variety of physiological processes that depend on ovarian steroids. The purpose of the present proposal is to provide insight into the intricate cellular and molecular mechanisms involved in gonadotropin regulated folliculogenesis in general and granulosa cell function in particular. Because conventional granulosa cell cultures result in the loss of follicular structure and alteration in cell functions, we have developed an alternative approach to study follicular functions by use of isolated intact preantral follicles from the hamster ovary and a long-term culture system for their in vitro development. This technique opens an entirely new dimension to study directly the physiology and biochemistry of proliferating follicular cells in their native, follicular microenvironment. We have determined that follicular cells in these cultures synthesize cAMP and steroids, proliferate in response to gonadotropins; express gonadotropin receptors as well as unique follicular proteins. We have observed that mitogenic action of FSH is transduced via EGF. Radioimmunoassay data, Western blotting and immunoprecipitation studies indicated that the hamster ovary has both EGF, TGF beta1 and beta2-like proteins, and EGF receptors. However, the cellular and molecular changes during development of the follicles and the roles of growth factors in these processes remain to be determined. I hypothesize that gonadotropin and steroid regulation of follicular cell proliferation and differentiation depend upon critical modulation of the activities of ovarian growth factors (e.g., EGF and TGFs-beta) and their receptors. Disruption of this process results in malfunctions in granulosa cells and sterility. The present study will focus on one important question: (1) Do gonadotropins regulate folliculogenesis by modulating ovarian EGF and TGFs-beta (beta1 and beta2) activities? The study will involve (1) immunohistochemical analyses of growth factor expression and their hormonal control during in vivo and in vitro follicular development; (2) biochemical analyses of growth factor effects on follicular growth and steroidogenesis, and (3) immunohistochemical and biochemical assessment of EGF- receptors during hormonal control of follicular development. Identification of the pathway for gonadotropin action in intact ovarian follicles will significantly add to our knowledge of the fundamental mechanisms of folliculogenesis.