ORGANIZATION OF MALE REPRODUCTIVE NEURAL CIRCUITS

男性生殖神经​​回路的组织

• 批准号: 6126129
• 负责人: ANNE Z MURPHY
• 金额: $ 17.58万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-12-01 至 2002-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6126129
• 关键词: behavioral /social science research tag; brain electrical activity; brain stem; central neural pathway /tract; efferent nerve; electrophysiology; electrostimulus; fluorescent dye /probe; gamma aminobutyrate; immunocytochemistry; laboratory rat; male; motor neurons; neural information processing; neural transmission; neuroanatomy; penis erection; preoptic areas; prosencephalon; radiotracer; sex behavior; spinal cord; spinal reflex; steroid hormone receptor; suid alphaherpesvirus 1

DESCRIPTION: (Adapted From The Applicant's Abstract) The goal of this research is to elucidate the neural mechansims by which specific forebrain, brainstem and spinal cord sites coordinate male reproductive behavior. Our new preliminary studies suggest a potential pathway that mediates forebrain influences on L6/S1 cord. This circuit comprises the MPO-->PGi-->spinal cord. The nucleus paragigantocellularis (PGi) in the ventrolateral medulla receives direct input from the MPO and projects heavily to the L6/S1 cord. Our preliminary data show that descending projections from the PGi selectively terminate within the motoneuronal pools that innervate the pelvic viscera. Aim 1 will test the hypothesis that MPO projections target PGi neruons that project to the lumbosacral spinal cord. A combined approach using both antero and retrograde tracers will be used to delineate the anatomical organization of MPO-->PGi-->spinal cord circuit. Spinal sexual reflexes are under tonic descending inhibition, presumably via input from the PGi. Recent studies suggest that MPO neuronal activity must increase for normal male reproductive behavior to occur. We postulate therefore that increased MPO activity before and during copulation functions, in part, to reduce the tonic inhibition ("disinhibition hypothesis") on spinal motor reflexes. Aim 2 employs coordinate neuroanatomical, immunocytochemical and electrophysiological techniques to test this disinhibition hypothesis: MPO activation inhibits PGi-->spinal cord neurons allowing for spinally mediated sexual reflexes to occur. The MPO and its output to the PGi are central for the initiation and maintenance of male sex behavior. Aim 3 tests the hypothesis that the MPO-->PGi circuit is selectively engaged during male sex behavior; activation of this circuit during copulation inhibits PGi pudendal premotor neurons via the release of GABA. As copulation is a steroid dependent behavior, we predict that the critical neural substrates along this MPO-->PGi-->spinal cord circuit will contain receptors for gonadal steroids. These studies will provide the first functional characterization of the MPO-->PGi-->spinal cord pathway. Together, these studies will provide detailed anatomical and physiological data on a neural circuit regulating male sex behavior.

描述：（改编自申请人的摘要） 这项研究的目的是阐明神经机制 特定的前脑、脑干和脊髓部位协调男性 生殖行为。我们新的初步研究表明潜在的 介导前脑对 L6/S1 脊髓影响的通路。这个电路 包括 MPO-->PGi-->脊髓。副巨细胞核 腹外侧髓质 (PGi) 接收来自 MPO 的直接输入 并大量突出到 L6/S1 线。我们的初步数据表明 PGi 的下降投影选择性地终止于 支配盆腔内脏的运动神经元池。目标 1 将进行测试 MPO 投影针对 PGi 神经元的假设 腰骶脊髓。结合使用 antero 和 逆行示踪剂将用于描绘解剖组织 MPO-->PGi-->脊髓回路。脊髓的性反射低于 强直下行抑制，大概是通过 PGi 的输入。最近的 研究表明，正常男性的 MPO 神经元活性一定会增加 生殖行为的发生。因此我们假设增加 交配前和交配期间的 MPO 活性部分是为了减少 脊髓运动的强直抑制（“去抑制假说”） 反射。目标 2 采用协调神经解剖学、免疫细胞化学 和电生理学技术来测试这种去抑制 假设：MPO 激活抑制 PGi--> 脊髓神经元 脊髓介导的性反射发生。 MPO 及其输出 PGi 对于男性性的启动和维持至关重要 行为。目标 3 测试 MPO-->PGi 电路的假设 男性有选择性地进行性行为；该电路的激活 交配期间通过释放抑制 PGi 阴部前运动神经元 GABA。由于交配是类固醇依赖性行为，我们预测 沿着 MPO-->PGi-->脊髓的关键神经基质 电路将包含性腺类固醇的受体。这些研究将 提供 MPO-->PGi--> 脊髓的第一个功能表征 绳索通路。这些研究将共同​​提供详细的解剖学信息 以及调节男性性行为的神经回路的生理数据。