REGULATION OF OVARIAN FOLLICULAR ESTRADIOL PRODUCTION

这项建议的目标是确定因素和条件 调节卵泡中雌二醇的合成。雌二醇是 排卵前卵泡发育的主要类固醇产物 持续的雌二醇分泌对于卵泡达到 排卵状态。有证据表明，许多物种 雌激素的产生既需要卵泡膜细胞，也需要颗粒细胞。 因为膜细胞产生雄激素，雄激素被芳香化成 雌二醇由小球细胞分泌。FSH和FSH都被认为是 黄体生成素对卵泡发育和雌二醇是必不可少的 分泌物。虽然黄体生成素刺激许多人雄激素的产生 卵泡刺激素和促黄体生成素在调节卵泡刺激素转化中的作用 除了在大鼠身上，雄激素对雌二醇的作用知之甚少。这 一项旨在研究促卵泡激素和促黄体生成素在 黄牛类固醇激素的发生与卵泡发育 卵泡内类固醇作为潜在调节因子的作用 卵泡类固醇的产生。 具体地说，内源性促性腺激素水平将在 在牛发情周期的特定时间注射 抑制素或抗黄体生成素抗血清。对卵泡的影响 体内的发育和退化将通过以下方式进行评估 超声检查卵巢和某些实验中的卵泡 将被分离并培养卵泡细胞以确定 内源性促性腺激素水平变化对其影响 类固醇生成能力。在其他实验中， 雄激素和雌二醇作为卵泡内调节剂 类固醇的发生将通过培养卵泡膜和/或 黄牛排卵前卵泡颗粒细胞和 不同浓度和它们的组合的大鼠 类固醇，在促性腺激素存在和不存在的情况下。最后， 卵泡雌二醇的产生与卵泡发育的关系 将使用黄体酮和催产素来探索黄体生成。 分泌物和颗粒细胞形态作为标记物 黄体化。 拟议的实验将使我们更好地了解 促性腺激素和类固醇在调节血管紧张素转换酶中的作用 因此，卵泡雌激素的分泌最终可能导致 开发更好的诱导排卵和 调节生育。

The objective of this proposal is to identify factors and conditions that regulate estradiol synthesis in ovarian follicles. Estradiol is the dominant steroid product of developing preovulatory follicles and continued estradiol secretion is essential for follicles to reach ovulatory status. There is evidence for a number of species that both theca and granulosa cells are needed for estradiol production because the theca cells make androgen which is aromatized to estradiol by the grandulosa cells. It is believed that both FSH and LH are essential for follicular development and estradiol secretion. Although LH stimulates androgen production in many species, the roles of FSH and LH in regulating the conversion of androgen to estradiol are poorly understood, except in rats. This proposal is designed to investigate the roles of FSH and LH in steroidogenesis and follicle development in cattle and to examine the actions of intrafollicular steroids as potential regulators of follicular steroid production. Specifically, endogenous levels of gonadotropins will be altered at specific times during the bovine estrous cycle by injections of inhibin or an antiserum to LH. The effects on follicular development and regression will be assessed in vivo by ultrasonography of the ovaries and in some experiments follicles will be isolated and follicle cells cultured to determine the effects of altered endogenous gonadotropin levels on their steroidogenic capabilities. In other experiments the roles of androgen and estradiol as intrafollicular regulators of steroidogenesis will be explored by culturing theca and/or granulosa cells obtained from preovulatory follicles of cattle and rats with various concentrations and combinations of these steroids, in the presence and absence of gonadotropins. Finally, the relationship between follicular estradiol production and luteinization will be explored, using progesterone and oxytocin secretion and granulosa cell morphology as markers for luteinization. The proposed experiments will provide a better understanding of the actions of gonadotropins and steroids in the regulation of follicular estradiol secretion and thus, may eventually lead to the development of better methods of inducing ovulation and regulating fertility.