CONTROL OF PROLACTIN SECRETION BY CATECHOLAMINES

这一建议是基于我们的发现，即脑下垂体后叶抑制 垂体腺分泌催乳素和黄体生成素，但不分泌卵泡刺激素。鉴于 后叶多巴胺能抑制催乳素分泌 (DA)系统，抑制黄体生成素的机制尚不清楚，但 似乎牵涉到后叶、下丘脑 促性腺激素释放激素和性腺激素。研究将沿着三条线进行：1) 垂体后叶在调节催乳素和黄体生成素分泌中的作用。一个。 急性后叶切除术对催乳素、促黄体生成素和卵泡刺激素的影响 在发情前期之前和之后立即分泌，并 研究与性腺类固醇的可能相互作用。B.确定 慢性后叶切除对周期性的长期影响， 哺乳和青春期前成熟。2)催乳素的多巴胺能调节 分泌物。A.测量垂体门静脉血中DA的分泌 后叶切除术后。B.要比较激活 下丘脑和垂体后叶的多巴胺及其系统 利用体内和体外多巴蓄积改变催乳素分泌 以DA生物合成作为酪氨酸羟基酶活性的指标。C.至 研究后叶是否独立于下丘脑 在生产和/或分泌DA的过程中利用移植和 下丘脑-后部损伤实验及器官培养 脑下垂体系统。(3)后叶抑制促黄体生成素的分泌。A.至 后路手术前后门静脉血LHRH分泌的测定 肺叶切除术。B.确定垂体前叶可能发生的变化 后叶切除术后对外源性GnRH的敏感性。C.确定 已知的垂体后叶提取物和物质的能力 存在于后叶以拮抗LHRH对黄体生成素的刺激 利用培养的垂体前叶细胞进行分泌。这项研究将 扩展我们对功能关系的理解 内分泌和神经系统，并将有助于更好的诊断 以及治疗大脑、垂体和生殖功能障碍。

The proposal is based on our findings that the posterior pituitary inhibits PRL and LH, but not FSH, secretion from the anterior pituitary. Whereas the inhibition of PRL secretion is mediated by posterior lobe dopaminergic (DA) system, the mechanism by which LH is inhibited is yet unknown, but appears to involve interactions between the posterior lobe, hypothalamic GnRH and gonadal steroids. Research will proceed along three lines: 1) The role of the posterior pituitary in regulating PRL and LH secretion. a. To determine the effects of acute posterior lobectomy on PRL, LH and FSH secretion immediately before and after the proestrus surge, and to investigate possible interactions with gonadal steroids. b. To determine the long term effects of chronic posterior lobectomy on cyclicity, lactation and prepubertal maturation. 2) Dopaminergic regulation of PRL secretion. a. To measure DA secretion into hypophysial portal blood before and after posterior lobectomy. b. To compare between the activation of the hypothalamic and posterior pituitary DA and systems under conditions of altered PRL secretion by utilizing in vivo DOPA accumulation and in vitro DA biosynthesis as indices for tyrosine hydroxylase activity. c. To investigate whether the posterior lobe is independent of the hypothalamus in the production and/or secretion of DA by utilizing transplantation and lesion experiments as well as organ culture of the hypothalamo-posterior pituitary system. 3) Posterior lobe inhibition of LH secretion. a. To measure LHRH secretion into portal blood before and after posterior lobectomy. b. To determine possible changes in anterior pituitary sensitivity to exogenous GnRH after posterior lobectomy. c. To determine the ability of posterior pituitary extracts and substances known to be present in the posterior lobe to antagonize LHRH stimulation of LH secretion utilizing cultured anterior pituitary cells. This study will extend our understanding of the functional relationship between the endocrine and the nervous systems, and will contribute to better diagnosis and treatment of brain, pituitary and reproductive dysfunctions.