Prostaglandin Receptors in Primate Ovulatory Follicles

排卵对于成功繁殖是必不可少的。排卵期黄体生成素激增刺激 排卵周卵泡产生前列腺素E2(PGE2)，这是卵丘扩张所必需的 颗粒细胞、卵泡破裂、卵母细胞释放。阻断PGE2的产生会导致排卵失败， 前列腺素E_2治疗不孕症以及抑制前列腺素E_2合成/作用的支持研究 作为潜在的避孕药。为了揭示PGE2刺激排卵周围事件的机制，这项研究 该建议提出了一个总体假设，即四种前列腺素E_2(EP)受体中的每一种在 排卵。首先，我们将确定哪些EP受体是由功能不同的亚群表达的 排卵周卵泡内的颗粒细胞。使用激光捕获显微解剖以及 免疫荧光检测猴卵巢组织切片中的EP，我们将确定EP受体(S) 存在于卵丘、基底壁和胃窦壁颗粒细胞以及位于 毛囊顶端。这些亚群中的每一个都在排卵中扮演着独特的角色，我们预计每个亚群 亚群表达所有EP受体的一个独特的子集。其次，我们将演示每个EP 受体介导PGE2刺激的所有排卵过程的一个子集。已知前列腺素E_2能刺激 颗粒细胞孕酮生成、卵丘扩张、卵泡破裂。颗粒细胞培养为 以及猕猴的卵泡内注射将被用来证明针对每种EP的激动剂 受体刺激PGE2介导的颗粒细胞功能中的一部分，但不是全部。最后，我们 将确定哪些EP受体可以在灵长类围排卵期的颗粒细胞中传递PGE2信号 毛囊。颗粒细胞将被四种EP受体的特异性激动剂处理，以及 通过这些G蛋白偶联受体产生的细胞内信号将被评估。每个EP受体将 可能通过独特的细胞内反应对激动剂刺激做出反应。拟议的研究很可能 证明每个EP受体介导对PGE2的围排卵期反应的一个特定子集 在灵长类毛囊内。这些数据将有助于有针对性的药理学方法选择性地 刺激或抑制排卵过程的基本特征，并可能最终导致 不孕不育的新疗法和新的避孕选择。

Ovulation is essential for successful reproduction. The ovulatory luteinizing hormone surge stimulates periovulatory follicles to produce prostaglandin E2 (PGE2), which is required for expansion of the cumulus granulosa cells, follicle rupture, and oocyte release. Blockade of PGE2 production causes ovulation failure, supporting investigation of PGE2 as a treatment for infertility as well as inhibition of PGE2 synthesis/action as a potential contraceptive. To unravel the mechanism by which PGE2 stimulates periovulatory events, this proposal puts forth the overall hypothesis that each of the four PGE2 (EP) receptors has a unique function in ovulation. First, we will determine which EP receptors are expressed by functionally-distinct subpopulations of granulosa cells within periovulatory follicles. Using laser capture microdissection as well as immunofluorescent EP detection in monkey ovarian tissue sections, we will identify the EP receptor(s) present in cumulus, basal mural, and antral mural granulosa cells as well as granulosa cells located at the follicle apex. These subpopulations each play a unique role in ovulation, and we anticipate that each subpopulation expressesa unique subset of all EP receptors. Second, we will demonstrate that each EP receptor mediates a subset of all PGE2-stimulated periovulatory processes. PGE2 is known to stimulate granulosa cell progesterone production, cumulus expansion, and follicle rupture. Granulosa cell cultures as well as intrafollicular injection in macaques will be utilized to demonstrate that agonists specific for each EP receptor stimulate some, but not all, of these essential PGE2-mediated granulosa cell functions. Finally, we will determine which EP receptors can transduce the PGE2 signal in granulosa cells of primate periovulatory follicles. Granulosa cells will be treated with agonists specific for each of the four EP receptors, and intracellular signals generated via these G protein coupled receptors will be assessed. Each EP receptor will likely respond to agonist stimulation with a unique intracellular response. The proposed studies will likely demonstrate that each EP receptor mediates a specific subset of the total periovulatory responseto PGE2 within the primate follicle. These data will facilitate a targeted pharmacological approach to selectively stimulate or inhibit essential features of the ovulatory process and may ultimately lead to the development of new treatments for infertility and novel contraceptive options.