ANGIOTENSIN II AND PROLACTIN RELEASE--ROLE OF ESTROGEN

描述（摘自申请人摘要）：血管紧张素II（AII），一种 产生八肽，其是肾素-血管紧张素系统的组分， 在大鼠和人类的脑垂体前叶中， 调节催乳素的旁分泌（大鼠）或自分泌（人）作用 分泌物 本研究拟探讨雌激素对大鼠 催乳素对旁分泌介质AII的敏感性。 具体而言是 有待检验的假设是，雌激素分泌的模式和水平 (or替代）影响垂体前叶催乳素对 AII和LHRH诱导的催乳素分泌刺激。 卵巢切除， 青春期前的雌性大鼠将注射雌激素和孕酮， 以模拟发情周期的方式诱导LH激增。 第二组 的卵巢切除动物将不接受类固醇，第三组将 而不是去卵巢 这些动物的脑垂体前叶细胞 月龄将暴露于生理剂量的AII和LHRH， 确定催乳素分泌反应。 肌醇积累 磷酸盐（IP），介导AII刺激的第二信使， 催乳素和AII受体结合特性也将是 研究了

DESCRIPTION (Adopted from applicant's abstract): Angiotensin II (AII), an octapeptide that is a component of the renin-angiotensin system, is produced within the anterior pituitary gland of rats and humans, and appears to play a paracrine (rat) or autocrine (human) role in regulation of prolactin secretion. This research proposes to examine the effects of estrogen on rat lactotroph sensitivity to the paracrine mediator AII. Specifically, the hypothesis to be tested is that the pattern and levels of estrogen secretion (or replacement) influences anterior pituitary lactotroph sensitivity to AII-and LHRH-induced stimulation of prolactin secretion. Ovariectomized, prepubertal female rats will be injected with estrogen and progesterone to induce LH surges in a pattern that mimics estrous cyclicity. A second group of ovariectomized animals will receive no steroids, and a third group will not be ovariectomized. Anterior pituitary cells from these animals at six months of age will be exposed to physiological doses of AII and LHRH to determine the prolactin secretory response. Accumulation of inositol phosphates (IP), the second messenger which mediates the AII stimulation of lactotrophs, and AII receptor binding characteristics will also be investigated.