MEASUREMENT OF HYPOTHALAMIC HORMONE RELEASE

总体目标是定义数量和时间关系 选定的下丘脑激素的分泌和下丘脑激素的分泌 催乳素和黄体生成素。这一方法将涉及同时 监测下丘脑和垂体前叶激素的分泌。 具体目标是：(1)检验睾丸激素、 尤其是睾丸素，使LHRH升高，同时抑制黄体生成素。我们会做的 这是通过监测茎正中隆起(SME)灌流液中的LHRH来实现的。 清醒绵羊血液推拉套管(PPC)和促黄体生成素(LH)采集， Wethers，和睾丸激素治疗的Wethers；(2)检验假设 性腺激素对促黄体生成素和促性腺激素释放激素的分泌有不同的时间效应。 我们将通过监测中小企业LHRH浓度的变化来实现这一点 PPC采集的灌流液和完好母羊血液中的黄体生成素 发情周期的各个阶段；(3)检验假设 光周期诱导的催乳素分泌变化主要是由 通过多巴胺(DA)分泌的变化。我们将通过监控 多巴胺、多巴胺代谢产物和血管活性肠液的浓度变化 清醒绵羊SMEPPC灌流液中血管活性肠肽的变化 长光周期和短光周期。将测定静脉血中的催乳素； (4)检验吗啡促进催乳素分泌的假说 主要是通过减少DA的分泌。我们会监测DA，DA代谢物， PPC灌流液中TRH、VIP和血液中催乳素的浓度 用生理盐水或吗啡处理清醒母羊；(5)测试 哺乳通过减少DA分泌诱导催乳素释放的假说 升高TRH或VIP的分泌。我们会监测DA，DA代谢物， PPC灌流液中TRH和VIP浓度及血液中催乳素浓度 有意识的母羊在哺乳前、哺乳期间和哺乳后；以及(6)测试 环境温度升高导致催乳素释放的假说 主要由TRH分泌增加所介导。我们会监控地方检察官， PPC灌流液和催乳素中DA代谢物、TRH和VIP浓度 清醒母羊暴露于高空暴露前、期间和之后的血液中 环境温度。

The overall aim is to define quantitative and temporal relationships between secretion of selected hypothalamic hormones and secretion of prolactin and luteinizing hormone. The approach will involve simultaneous monitoring of hypothalamic and anterior pituitary hormone secretion. Specific aims are: (1) To test the hypothesis that testicular hormones, particularly testosterone, elevate LHRH while depressing LH. We will do this by monitoring LHRH in perfusates of the stalk median eminence (SME) collected by push-pull cannulae (PPC) and LH in blood of conscious rams, wethers, and testosterone-treated wethers; (2) To test the hypothesis that gonadal steroids have divergent temporal effects on LH and LHRH secretion. We will do this by monitoring changes in LHRH concentrations in SME perfusates collected by PPC, and LH in blood of intact ewes during three stages of the estrous cycle; (3) To test the hypothesis that photoperiod-induced changes in prolactin secretion are mediated primarily by changes in secretion of dopamine (DA). We will do this by monitoring changes in concentrations of DA, DA metabolites, and vasoactive intestinal peptide (VIP) in PPC perfusates of the SME of conscious ewes exposed to long and short photoperiods. Prolactin will be measured in venous blood; (4) To test the hypothesis that morphine elevates prolactin secretion primarily by reducing DA secretion. We will monitor DA, DA metabolites, TRH, and VIP concentrations in PPC perfusates and prolactin in blood of conscious ewes treated with saline solution or morphine; (5) To test the hypothesis that suckling induces prolactin release by reducing DA secretion and elevating TRH or VIP secretion. We will monitor DA, DA metabolites, TRH and VIP concentrations in PPC perfusates and prolactin in blood of conscious ewes prior to, during, and after suckling; and (6) To test the hypothesis that prolactin release induced by elevated ambient temperature is mediated primarily by increased secretion of TRH. We will monitor DA, DA metabolites, TRH, and VIP concentrations in PPC perfusates and prolactin in blood of conscious ewes before, during, and after exposure to elevated ambient temperatures.