NEUROENDOCRINE REGULATION OF PROLACTIN SECRETION

催乳素分泌的神经内分泌调节

• 批准号: 3320234
• 负责人: Michael Selmanoff
• 金额: $ 9.79万
• 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 1988-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3320234
• 关键词: brain mapping; bromocriptine; dissection; dopamine; hormone inhibitor; hormone regulation /control mechanism; hypophysectomy; 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结节漏斗的作用， 多巴胺能（TIDA）神经元在前额叶催乳素（PRL）释放中的作用 大鼠脑下垂体。 一种显微切割技术 其允许离散地去除细胞核、终端投影场 老鼠大脑中的神经纤维通路 高度敏感的发展 多巴胺（DA）、去甲肾上腺素（NE）和 3，4-二羟基苯乙酸（DOPAC）现在允许测定DA和 NE周转和主要DA代谢产物DOPAC在这样的显微解剖的大脑 地区 这些显微技术使得神经化学分析 神经内分泌事件的分辨率水平远远高于以前 可能 神经元活性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组织浓度的测量。 神经化学动力学 正中隆起（ME）中的TIDA终末将与其他已知的TIDA终末进行对比。 多巴胺能投射到尾状核、嗅结节和内侧核 视前核在控制PRL分泌的内分泌操作。 TIDA神经元特异性的变化因此可以被识别并与PRL相关 通过直接放射免疫测定法测定的外周循环中的滴度。 将对哺乳引起的PRL升高进行神经化学分析 需要估计TIDA神经元活动在这一戏剧性的 神经内分泌反应 催乳素对TIDA的短环负反馈作用 将在切除垂体的大鼠中研究神经元。 一个神经活动点 2-溴-α-麦角隐亭（CB-154），临床上用于抑制PRL的药物 分泌和治疗帕金森病，将在 TIDA神经元的水平。 这些实验证实了 TIDA神经元作为延长抑制因子（PIF）的神经分泌 神经元