DAYLIGHT DEPENDENT CONTROL OF PROLACTIN SECRETION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 这项建议的目的是了解日光驱动特定的感觉-神经内分泌系统来调节催乳素分泌变化的机制。来自绵羊研究的明确证据表明，日光调节松果体的褪黑素输出，而松果体反过来又控制脑下垂体远端催乳素的分泌。这种效应是通过垂体腺结节部释放的一种特定因子来传递的。这种结节因子的特性以及它如何调节催乳素的释放尚不清楚。根据强有力的初步数据，我们假设这个因子是速激肽。这项拟议的研究将利用一系列研究来确定速激肽在体内分泌到垂体门静脉循环中，以及速激肽对催乳素释放的影响。免疫细胞化学和RT-PCR研究将确定日光如何通过褪黑素驱动结节细胞分泌机制的变化。这项研究将挑战普遍的教条，即催乳素的调节完全由神经元起源的因素驱动。它将提供对基本感觉-神经内分泌系统的新见解，并阐明日光驱动这一系统的具体机制。它还将对特发性高催乳素血症的潜在原因产生新的见解，特别是由所谓的“茎效应”产生的那些原因。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The aim of this proposal is to understand the mechanisms by which daylight drives a specific sensory-neuroendocrine system to regulate changes in prolactin secretion. Clear evidence from research on sheep shows that daylight regulates melatonin output from the pineal gland, which in turn, controls prolactin secretion from the pars distalis of the the pituitary gland. This effect is transduced through a specific factor released by the pars tuberalis of the pituitray gland. The identity of this pars tuberalis factor and how it regulates prolactin release is unknown. Based on strong preliminary data, we hypothesize that this factor is a tachykinin. The proposed research will utilize a combination of studies to determine the in vivo secretion of tachykinins into the hypophyseal portal circulation and the effects of tachykinins on prolactin release. Immunocytochemical and RT-PCR studies will establish how daylight, through melatonin, drives changes in the cellular secretory machinery of the pars tuberalis. This research will challenge the prevailing dogma that prolactin regulation is solely driven through factors of neuronal origin. It will provide novel insight into a fundamental sensory-neuroendocrine system and elucidate the specific mechanisms whereby daylight drives this system. It will also generate new insight into potential causes of idiosyncratic hyperprolactinemia, especially those generated by the so-called "stalk-effect".