Neurotensin: A Novel Mediator of Ovulation

女性的生育能力取决于导致排卵的一连串事件。这种排卵障碍 在所有女性不孕症病例中，有25%的人是由排卵过程导致的，这支持了排卵在生殖过程中的重要作用。 并为探索排卵过程的介质提供了一个强有力的前提。我们建议 神经降压素是排卵过程的关键调节物之一。 排卵是由排卵前LH峰增加卵巢卵泡内介质启动的 其作用是促使卵母细胞释放。我们的新的和令人兴奋的初步数据表明，神经降压素（NTS）， 一种小的神经肽，是排卵的关键卵泡内介质。这是基于我们的发现，即NTS是 人排卵卵泡颗粒细胞中差异表达最多的基因之一， 排卵期促性腺激素激增后的15,000倍。同样地，LH也快速且显著地增加NTS 啮齿动物和猴排卵卵泡颗粒细胞中的mRNA。重要的是，注射神经降压素 进入猴排卵前卵泡的抗体阻断卵母细胞释放，导致未破裂卵泡黄素化， 与排卵障碍一致类似地，缺乏NTS表达的小鼠形成未破裂的黄素化卵泡， LH/hCG给药后，NTS受体拮抗剂抑制卵母细胞的释放，在一个新的体外实验中， 小鼠排卵模型。然而，除了我们的初步数据，没有什么是已知的时间 NTS受体的表达或NTS在排卵和女性生育中的功能。这些问题将 通过利用特殊背景、技术 专业知识和项目负责人的模型。我们将使用一个高影响力的转化模型， 将在三个指定的时间点之前和时间点收集来自人排卵期卵泡的颗粒和卵泡膜。 在小鼠体内和体外研究中进行的hCG（早期、晚期和排卵后）补充后的时间 还有猴子对NTS及其受体在排卵卵泡中的表达调控将有更深入的了解 并在目标1中对女性、猴子和小鼠进行了比较。NTS对小鼠排卵的刺激作用 卵泡的颗粒细胞、卵泡膜细胞、卵丘细胞和内皮细胞将在目标2中阐明。NTS的行动 将使用小鼠在小鼠和猴子身上揭示排卵以及其他关键生殖过程 Aim 3中缺乏NTS表达、NTS受体拮抗剂和NTS中和抗体。一个主要优势 该提案的一个重要部分是咖喱博士和Duffy博士之间的协作互动，以解决NTS的功能 及其受体在多个物种的排卵期事件中的作用，包括特殊的人类卵巢组织 和非人灵长类动物的体内研究，这是一种与人类生殖高度相关的动物模型， 功能因此，了解卵母细胞的基本原理具有特殊的意义 发布，为改善不孕妇女的结局或相反提供了一个基本平台 为女性避孕提供防止卵母细胞释放的靶点。

A woman’s fertility is dependent on the cascade of events leading up to ovulation. Defects in this ovulatory process result in 25% of all female infertility cases, supporting the paramount role of ovulation in reproductive success and providing a strong premise to explore mediators of the ovulatory process. We propose that neurotensin is one of these pivotal regulators of the ovulatory process. Ovulation is set in motion by the preovulatory LH surge which increases ovarian intrafollicular mediators that act to bring about oocyte release. Our novel and exciting preliminary data indicate that neurotensin (NTS), a small neuropeptide, is a key intrafollicular mediator of ovulation. This is based upon our findings that NTS is one of the most differentially-expressed genes in the granulosa cells of the human ovulatory follicle, up to 15,000 fold after the ovulatory gonadotropin surge. Likewise, LH also rapidly and significantly increases NTS mRNA in granulosa cells from rodent and monkey ovulatory follicles. Importantly, injection of a neurotensin antibody into monkey preovulatory follicles blocked oocyte release resulting in luteinized unruptured follicles, consistent with failure of ovulation. Similarly, mice lacking NTS expression form luteinized unruptured follicles following LH/hCG administration, and a NTS receptor antagonist inhibits oocyte release in a novel in vitro model of mouse ovulation. Yet, other than our preliminary data, nothing is known regarding the temporal expression of NTS receptors or the function of NTS in ovulation and female fertility. These questions will be addressed in this proposal through a collaborative approach utilizing the exceptional backgrounds, technical expertise, and models of the Project Leaders. We will make use of a high-impact, translational model where the granulosa and theca from human periovulatory follicles will be collected prior to and at three designated times after hCG (early, late and postovulatory) to complement in vivo and in vitro studies performed with mice and monkeys. The regulation of NTS and NTS receptor expression in the ovulatory follicle will be illuminated and compared across women, monkeys and mice in Aim 1. The ovulatory functions stimulated by NTS in granulosa, theca, cumulus, and endothelial cells of the follicle will be elucidated in Aim 2. The actions of NTS on ovulation, as well as other key reproductive processes, will be revealed in mice and monkeys using mice lacking NTS expression, NTS receptor antagonists, and NTS-neutralizing antibodies in Aim 3. A major strength of this proposal is the collaborative interactions between Dr. Curry and Dr. Duffy to address the function of NTS and its receptors in periovulatory events across multiple species, including exceptional human ovarian tissues and in vivo studies of non-human primates, an animal model with high relevance to human reproductive function. Thus, there is an exceptional degree of significance in understanding the basic tenets of oocyte release which provides a fundamental platform to either improve outcomes for infertile women or conversely provide targets to prevent oocyte release for female contraception.