Neuroendocrine Regulation of Prolactin Secretion

9423926 Badura催乳素是一种由脑垂体前叶分泌的蛋白质激素，参与哺乳动物的大量生理和行为过程，包括发情周期、免疫系统激活、应激、产奶和母性行为。虽然这种激素显然与许多不同的生理系统有关，但其确切的作用机制和控制催乳素分泌的方式仍有待解决。研究它很困难，不仅因为它的多种作用模式，而且因为催乳素激增和慢性分泌物似乎受到不同的调节。巴杜拉博士正在使用一个聪明的模型系统来检查催乳素释放的神经内分泌调节。她利用了一个事实，即催乳素显示出明显的年度波动，这与光周期的变化相对应，很可能是白天的长度。巴杜拉博士将结合光周期线索来检查催乳素分泌调节的基础因素。她将专注于两种神经肽，血管活性肠多肽和催产素。这些多肽激素可能是调节因子，因为它们位于下丘脑的室旁核，这是一个大脑区域，她之前已经证明在刺激调节基础催乳素释放中发挥重要作用。使用最先进的神经解剖程序，Badura博士将确定作用部位和调节因子在神经内分泌控制这种生理相关激素的光周期变化表达中的相对贡献。剖析催乳素调节明显不相关的生理系统的机制，将增加我们对具有多重目标和功能的进化激素系统的适应性意义的理解。＊＊＊

9423926 Badura Prolactin, a protein hormone secreted by the anterior pituitary gland, is involved in a large number of physiological and behavioral processes in mammals, including estrus cyclicity, immune system activation, stress, milk production, and maternal behavior. While this hormone is clearly involved in many different physiological systems, the precise mechanism of action and the ways in which prolactin secretion is controlled remains to be resolved. It is difficult to study not only because of its multiple modes of action but because prolactin surges and chronic secretions appear to be differently regulated. Dr. Badura is using a clever model system to examine the neuroendocrine regulation of prolactin release. She is taking advantage of the fact that prolactin shows a marked annual fluctuation that corresponds with changes in photoperiod, most likely daylength. Dr. Badura will incorporate photoperiodic cues to examine the factors the underlie the regulation of prolactin secretion. She will be concentrating on two neuropeptides, vasoactive intestinal polypeptide and oxytocin. These peptides hormones are likely modulatory factors since they are located in the paraventricular nucleus of the hypothalamus, a brain region that she has previously shown to play an important role in the stimulatory modulation of basal prolactin release. Using state-of-the-art neuroanatomical procedures, Dr. Badura will identify the sites of action and the relative contributions of modulatory factors in the expression of photoperiodic changes in the neuroendocrine control of this physiologically relevant hormone. Dissecting the mechanisms by which prolactin regulates apparently unrelated physiological systems will increase our understanding of the adaptive significance of evolving hormonal systems that possess multiple targets and functions. ***