CONTROL AND INTEGRATION OF GNRH NEURAL PATHWAYS

GNRH 神经通路的控制和整合

• 批准号: 3311448
• 负责人: PAUL C GOLDSMITH
• 金额: $ 21.92万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1977
• 资助国家: 美国
• 起止时间: 1977-04-01 至 1996-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3311448
• 关键词: Macaca fascicularis; afferent nerve; animal puberty; dopamine; endorphins; estrogen receptors; excitatory aminoacid; gamma aminobutyrate; gonadotropin releasing factor; hormone regulation /control mechanism; immunocytochemistry; immunoelectron microscopy; median eminence; neural information processing; neuroanatomy; neuroendocrine system; neurotransmitters; norepinephrine; peroxidases; pituitary gonadal axis; progesterone receptors; serotonin; synapses

Scattered GnRH neurons in the primate hypothalamus perform different functions and engage in selective interactions. To establish which interactions are relevant to neuroendocrine regulation, (1) We will identify neuroendocrine GnRH neurons in the primate, and determine the afferent inputs involved in their control. We will identify neuroendocrine GnRH neurons in pre-ovulatory female primates by retrograde labeling from the median eminence (ME) and immunocytochemical (ICC) staining for GnRH with. DAB. We will use ICC staining with colloidal gold (red) to identify their specific afferents, e.g. dopamine (DA), norepinephrine (NE), and serotonin (5-HT), the peptide beta-endorphin (b-E), gamma-aminobutyric acid (GABA), and the excitatory amino acids (EAAs) glutamate and aspartate. Synapses will be characterized at the electron microscopic (EM) level and quantified. (2) We will determine which afferents mediate estrogen (E2) and progesterone (P4) feedback on neuroendocrine GnRH neurons. Since GnRH neurons lack E2 receptors, inhibitory feedback is thought to occur through afferent DA, b-E, or GABA neurons, which concentrate E2 and in some cases P4. We will use ICC staining with heavy metal-intensified DAB (black) to reveal neuronal nuclei containing E2 receptors in pre-ovulatory female primates, and identify neuroendocrine GnRH neurons with standard DAB (brown). We will perform ICC staining for DA, b-E, or GABA neurons with colloidal gold to identify which afferents mediate E2 feedback. Types and numbers of synapses will be evaluated by EM and quantified. Using the same protocol, we will perform ICC staining for P4 receptors and determine which afferents mediate P4 feedback. We will repeat these studies in early follicular and mid-luteal phase animals to examine feedback sites and effects of changing steroid levels. Puberty in primates involves reactivation of the dormant prepubertal GnRH pulse generator. While this implies that a competent GnRH neuronal system is present in juveniles, neuroanatomical changes which ma\, enhance pulsatile GnRH secretion have yet to be assessed. (3) We will determine if GnRH neuronal connections or afferent synapses are altered during the peripubertal period. We will perform double EM ICC staining for GnRH. neurons (with DAB) and their afferents (with colloidal gold) in prepubertal and adult male monkeys. We will quantify and compare the types, characteristics, and numbers of GnRH neuronal interactions and afferent synapses. Using serial plasma LH measurements (by RIA), we will identify peripubertal (nocturnal LH surge) animals, perform ICC staining, and evaluate participation of the neural changes observed. In subsequent studies, we will examine prepubertal and peripubertal female monkeys and quantify their GnRH neurointeractions. We will compare the data to that previously obtained in adult, cycling females, and correlate the observed changes with associated peripubertal events. Together, these studies will elucidate the nature of GnRH neuronal control, the generation of pulsatile GnRH secretion, and assess neuroanatomical changes contributing to the onset of puberty.

灵长类下丘脑中散在分布的促性腺激素释放激素神经元执行不同的功能 功能，并参与选择性的互动。为了确定哪一个 相互作用与神经内分泌调节有关，(1)我们将 鉴定灵长类神经内分泌GnRH神经元，并测定 参与其控制的传入输入。我们将确定 促性腺激素释放激素在排卵前期雌性灵长类中的神经内分泌作用 正中隆起逆行标记与免疫细胞化学 (ICC)GnRH染色。轻拍。我们将使用ICC染色 胶体金(红色)用于识别其特定的传入物质，例如多巴胺 (DA)、去甲肾上腺素(NE)和5-羟色胺(5-羟色胺)。 β-内啡(b-E)、γ-氨基丁酸(GABA)和兴奋性 氨基酸(EaAs)、谷氨酸和天冬氨酸。突触将成为 在电子显微镜(EM)水平上进行了表征和量化。(2) 我们将确定哪些传入神经调节雌激素(E2)和孕激素 (4)对神经内分泌GnRH神经元的反馈。由于促性腺激素释放激素神经元缺乏E2 受体，抑制性反馈被认为是通过传入DA发生的， B-E，或GABA神经元，集中在E2和某些情况下的P4。我们会 用ICC染色和重金属强化的DAB(黑色)显示 排卵前期雌性灵长类动物中含有E2受体的神经元核， 并用标准DAB(棕色)鉴定神经内分泌GnRH神经元。我们 将使用胶体对DA、b-E或GABA神经元进行ICC染色 金来确定哪些传入细胞介导了E2反馈。类型和数量 突触的数量将通过EM进行评估和量化。使用相同的 方案，我们将对P4受体进行ICC染色并确定 哪些传入神经参与了P4反馈的调节。我们将在 早期卵泡和黄体中期动物检查反馈部位 以及改变类固醇水平的影响。 灵长类动物的青春期包括休眠的青春期前的重新激活 GnRH脉冲发生器。虽然这意味着一个有能力的促性腺激素释放激素神经元 系统存在于青少年，神经解剖学上的变化， 促进促性腺激素释放激素的搏动性分泌还有待评估。(3)我们会 确定促性腺激素释放激素神经元连接或传入突触是否改变 在青春期前后。我们将进行双EM ICC染色 用于GnRH。神经元(用DAB)及其传入(用胶体金) 青春期前和成年雄性猴子。我们将量化并比较 促性腺激素释放激素神经元相互作用的类型、特征和数量 传入突触。使用连续的血浆促黄体生成素测量(通过RIA)，我们将 鉴定青春期(夜间黄体生成素激增)动物，进行ICC染色， 并评价参与观察到的神经变化。在随后的 研究，我们将检查青春期前和青春期周围的雌性猴子和 量化他们的促性腺激素释放激素神经相互作用。我们会将数据与此进行比较 以前在成年、骑自行车的雌性中获得，并将观察到的 伴随青春期相关事件的变化。总而言之，这些研究 将阐明GnRH神经元控制的本质，产生 脉动性促性腺激素释放激素分泌，并评估神经解剖学变化 到青春期的开始。