NEUROENDOCRINE GENES GOVERNING REPRODUCTION

这项研究的目的是为了了解糖尿病的分子生理学。 促性腺激素释放激素(GnRH)和阿片黑素皮质素原(POMC) 参与男性生殖的神经元。中的单元格数组。 下丘脑和前脑分泌GnRH，协调释放 脑下垂体促性腺激素最终控制睾丸功能。 大脑中的其他神经递质系统，包括 内源性阿片家族(如来自POMC的β-内啡肽)和 兴奋性氨基酸谷氨酸，处理荷尔蒙信号(例如， 睾丸素)，而睾丸素反过来调节分泌 促性腺激素释放激素细胞活性。我们的第一个目标是了解睾丸激素如何 调节GnRH细胞内基因产物的合成。在这里，我们 将重点介绍proGnRH处理酶[羧基肽酶H(CPH)和 α-酰胺酶(PAM)和谷氨酸受体(Glur-K1型)。 利用双重原位杂交，我们将绘制出 在解剖学定义的亚群中编码CPH、PAM和Glur-K1的基因 观察睾丸激素对GnRH神经元的调节作用。如果我们发现 睾丸激素会影响其中一个或多个基因的表达， 我们将继续检验这一假设，即睾丸激素对 促性腺激素分泌可归因于促性腺激素释放激素原过程的变化 或受体介导的谷氨酸敏感性的改变。我们会 通过将GnRH启动子连接到CPH的结构基因来实现这一点， PAm或Glur-K1，并使用这些构建物来创建和研究转基因小鼠 在GnRH中表达其中一个嵌合基因的多个拷贝 神经元。我们的第二个目标是学习更多关于分子生理学的知识 下丘脑对睾丸激素敏感的POMC神经元。我们和其他人 先前已经证明弓状核中的POMC神经元是 功能上的异质性，但分子特征决定了 这种异质性，以及除了POMC本身之外，基因产品是如何 这些神经元内部的调控是未知的。我们将在现场使用双人 用杂交法检测POMC mRNA和芳香酶或雌激素受体mRNAs 为了研究这些基因是如何受类固醇调节的 在解剖定义的POMC神经元的子集内。我们相信这是可行的 将促进细胞神经内分泌学知识的提高，并可能提供 了解与人类生殖有关的临床问题的线索。

The goal of this research is to understand the molecular physiology of gonadotropin-releasing hormone (GnRH) and pro-opiomelanocortin (POMC) neurons involved in male reproduction. An array of cells in the hypothalamus and forebrain secretes GnRH, which coordinates the release of the pituitary gonadotropins and ultimately governs testicular function. Other neurotransmitter systems in the brain, including members of the endogenous opioid family (e.g., beta-endorphin, from POMC) and the excitatory amino acid glutamate, process hormonal signals (e.g., testosterone) from the testis which, in turn, modulate the secretory activity of GnRH cells. Our first objective is to learn how testosterone regulates the synthesis of gene products within the GnRH cell. Here, we will focus on the proGnRH processing enzymes [carboxypeptidase H (CPH) and alpha-amidating enzyme (PAM)] and the glutamate receptor (GluR-K1 type). Using double in situ hybridization, we will map the distribution of the genes coding for CPH, PAM, and GluR-K1 within anatomically defined subsets of GnRH neurons and examine their regulation by testosterone. If we find that testosterone influences the expression of one or more of these genes, we will proceed to test the hypothesis that the effect of testosterone on gonadotropin secretion can be attributed to changes in pro-GnRH processing or alterations in receptor-mediated sensitivity to glutamate. We will approach this by coupling the GnRH promoter to the structural gene for CPH, PAM or GluR-K1 and use these constructs to create and study transgenic mice expressing multiple copies of one of these chimeric genes within GnRH neurons. Our second objective is learn more about the molecular physiology of testosterone-sensitive POMC neurons in the hypothalamus. We and others have previously shown that POMC neurons in the arcuate nucleus are functionally heterogeneous, but what molecular characteristics determine this heterogeneity and how gene products, in addition to POMC itself, are regulated within these neurons are unknown. We will use double in situ hybridization to measure POMC mRNA and aromatase or estrogen receptor mRNAs for the purpose of the studying how these genes are regulated by steroids within anatomically defined subsets of POMC neurons. We believe this work will foster improved knowledge of cellular neuroendocrinology and may offer clues to understanding clinical problems related to human reproduction.