NEUROENDOCRINE REGULATION OF PROLACTIN SECRETION

催乳素分泌的神经内分泌调节

• 批准号: 3320231
• 负责人: Michael Selmanoff
• 金额: $ 13.07万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 1978
• 资助国家: 美国
• 起止时间: 1978-07-01 至 1990-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3320231
• 关键词: brain mapping; bromocriptine; dissection; dopamine; hormone inhibitor; hormone regulation /control mechanism; hypophysectomy; hypothalamus; luteinizing hormone; median eminence; neural information processing; neurochemistry; neuroendocrine system; neurons; neurotransmitter metabolism; norepinephrine; oral behavior; pituitary gland; prolactin; prolactin releasing /inhibiting factor; radioimmunoassay; scintillation spectrometry; thin layer chromatography

This research seeks to further elucidate the role of tuberoinfundibular dopaminergic (TIDA) neurons in the release of prolactin (PRL) from the anterior pituitary gland in the rat. A microdissection technique has been introduced which allows for the discrete removal of nuclei, terminal projection fields and fiber pathways from the rat brain. The development of highly sensitive radioisotopic-enzymatic assays for dopamine (DA), norepinephrine (NE) and 3,4-dihydroxyphenylacetic acid (DOPAC) now allow for the determination of DA and NE turnover and the major DA metabolite DOPAC in such microdissected brain regions. In concert, these microtechniques allow for the neurochemical analysis of neuroendocrine events at a level of resolution far greater than previously possible. Neuronal activity will be assessed by two neurochemical indices: (1) the determination of DA and NE turnover (alpha-methyl-para-tyrosine method), and (2) measurement of DOPAC tissue concentrations. The neurochemical dynamics of TIDA terminals in the median eminence (ME) will be contrasted with other known dopaminergic projections to the caudate nucleus, olfactory tubercle and medial preoptic nucleus during controlled endocrine manipulations of PRL secretion. Changes specific to TIDA neurons may thus be identified and correlated with PRL titers in the peripheral circulation as determined by direct radioimmunoassay. A neurochemical analysis of the suckling-induced rise in PRL will be undertaken entailing estimation of TIDA neuronal activity during this dramatic neuroendocrine response. The short-loop negative feedback action of PRL on TIDA neurons will be investigated in hypophysectomized rats. A neural site of action of 2-brom-alpha-ergocryptine (CB-154), a drug used clinically to inhibit PRL secretion and in the treatment of Parkinson's disease, will be investigated at the level of the TIDA neurons. These experiments bear on the working hypothesis that TIDA neurons function as prolacting inhibitory factor (PIF) neurosecretory neurons.

本研究旨在进一步阐明漏斗结节的作用 多巴胺能 (TIDA) 神经元在前部释放催乳素 (PRL) 中的作用 大鼠的垂体。 显微切割技术已被引入 它允许离散去除核、终端投影场和 来自大鼠大脑的纤维通路。 高灵敏的发展 多巴胺 (DA)、去甲肾上腺素 (NE) 和放射性同位素酶测定 3,4-二羟基苯乙酸 (DOPAC) 现在可用于测定 DA 和 显微解剖脑中的 NE 周转率和主要 DA 代谢物 DOPAC 地区。 协同作用，这些微技术可以进行神​​经化学分析 神经内分泌事件的分辨率水平远高于以前 可能的。 神经元活动将通过两个神经化学指标进行评估：(1) DA 和 NE 周转率的测定（α-甲基-对酪氨酸法），以及 (2)DOPAC组织浓度测定。 神经化学动力学 中位隆起 (ME) 中的 TIDA 终端将与其他已知的终端进行对比 多巴胺能投射到尾状核、嗅结节和内侧 PRL 分泌的受控内分泌操作过程中的视前核。 因此，可以识别 TIDA 神经元特有的变化，并将其与 PRL 相关联 通过直接放射免疫测定法测定外周循环中的滴度。 将对哺乳引起的 PRL 升高进行神经化学分析 需要对这一戏剧性事件期间的 TIDA 神经元活动进行估计 神经内分泌反应。 PRL对TIDA的短环负反馈作用 将在垂体切除的大鼠中研究神经元。 神经作用部位 2-溴-α-麦角隐亭 (CB-154)，一种临床用于抑制 PRL 的药物 分泌和帕金森氏病的治疗，将在 TIDA 神经元的水平。 这些实验与工作假设有关 TIDA 神经元具有催乳抑制因子 (PIF) 神经分泌功能 神经元。