Homeostatic Origins of Motivation

描述(由申请人提供)：这是一份竞争性续签申请 用于资助研究，这些研究的总体目标是了解 动机行为的生物学基础，尤其是口渴、食盐量、 饥饿和饱足。提出了三个系列的实验。实验1 旨在确定影响口渴和口渴的早期进食后信号 大鼠加压素(VP)和催产素(OT)的分泌。为了追求这一点 目的：我们将确定(A)喝水是否会减少VP和 OT对静脉注射以外的兴奋性刺激的反应 盐负荷；(B)最后区和孤束核病变 (NTS)钝化喝水或灌胃氯化钠的快速效果 负荷，对VP和OT分泌的影响；以及(C)维持大鼠在 高盐饮食钝化饮水对Vp和Vp的快速抑制作用 OT分泌物。实验2试图确定口渴的兴奋性刺激。 在动脉低血压或低血容量期间，抑制刺激 动脉高血压时口渴。为了实现这一目标，我们将决定 (A)血管紧张素II和来自动脉压力感受器的神经信号 对低血压时的口渴有显著作用；(B)肾脏 传入神经对大鼠低血容量时的口渴有重要作用 以及(C)窦主动脉压力感受器是否起作用 对动脉高血压止渴有显著的抑制作用。 实验3试图确定神经垂体部的生理功能。 盐负荷或动脉低血压时大鼠的OT分泌。在……里面 为了实现这一目标，我们将确定(A)加班是否有重大贡献 当大鼠保持高盐饮食时，作为一种利钠激素；和(B) OT是否显著促进动脉肾素的分泌 低血压，从而调节引起的口渴。

DESCRIPTION (provided by applicant): This is a competing renewal application for grant support of research whose general goal is to understand the biological bases of motivated behavior, especially thirst, salt appetite, hunger and satiety. Three series of experiments are proposed. Experiment 1 seeks to determine the early postingestive signals that influence thirst and the secretion of vasopressin (VP) and oxytocin (OT) in rats. In pursuit of this aim, we will determine (a) whether water drinking reduces secretion of VP and OT in response to excitatory stimuli other than that provided by an intravenous NaCl load; (b) whether lesions of area postrema and nucleus tractus solitarius (NTS) blunt the rapid effect of water drinking, or of an intragastric NaCl load, on secretion of VP and OT; and (c) whether maintenance of rats on high-salt diet blunts the rapid inhibitory effect of water drinking on VP and OT secretion. Experiment 2 seeks to determine the excitatory stimuli for thirst during arterial hypotension or hypovolemia, and the inhibitory stimulus for thirst during arterial hypertension. In pursuit of this aim, we will determine (a) whether angiotensin II and neural signals from arterial baroreceptors contribute significantly to thirst during hypotension; (b) whether renal afferent nerves contribute significantly to thirst during hypovolemia in rats with NTS lesions; and (c) whether sinoaortic baroreceptors contribute significantly to the inhibitory effect of arterial hypertension on thirst. Experiment 3 seeks to determine the physiological functions of neurohypophyseal OT secretion in rats given NaCl loads or during arterial hypotension. In pursuit of this aim, we will determine (a) whether OT contributes significantly as a natriuretic hormone when rats are maintained on high-salt diet; and (b) whether OT contributes significantly to secretion of renin during arterial hypotension, and thus to mediation of the induced thirst.