NEURAL REGULATION OF THIRST

口渴的神经调节

• 批准号: 3406075
• 负责人: MASSAKO KADEKARO-KUTYNA
• 金额: $ 8.53万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-08-01 至 1989-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3406075
• 关键词: acetylcholine; angiotensin /renin /aldosterone hypertension; angiotensin II; autoradiography; baroreceptors; brain metabolism; denervation; homeostasis; laboratory rat; neural information processing; neurotransmitters; prosencephalon; serotonin; thirst; water drinking behavior

Neural regulation of water balance is mediated by a circuit that includes circumventricular and forebrain structures. These structures respond to plasma and cerebrospinal fluid hyperosmolality, angiotensin II and input from volume- and baroreceptors. Experiments outlined in this proposal will continue studies that we began five years ago. We will test the hypothesis that the metabolic activity of the subfornical organ, a circumventricular organ, is modified by sensory and humoral inputs and by several neurotransmitters. To test this hypothesis three groups of experiments were designed: (1) we will investigate whether the inputs from baroreceptors alter the functional activity of the subfornical organ in response to peripheral angiotensin II; (2) we will investigate whether the subfornical organ is the primary site of action of angiotensin II; and (3) we will investigate whether the subfornical organ is responsive to different neurotransmitters and whether multiple circuits are activated by them. The primary methodology will involve the autoradiographic (14C) deoxyglucose technique. The first question will be investigated in sino-aortic denervated and sham-operated preparations. The primary site of action of AII will be investigated in preparations in which connections between the subfornical organ and the anteroventral third ventricle (AV3V) area are interruped. Some investigators have indicated that the primary site of AII activation may be the AV3V area. If angiotensin II increases glucose utilization in the subfornical organ of lesioned rats to the same degree as in sham-operated animals, this will indicate that angiotensin II stimulation of the subfornical organ is not dependent on input from AV3V area. Multiplicity of circuits within the subfornical organ subserving drinking behavior will be examined by topically stimulating the subfornical organ with putative neurotransmitters angiotensin II, serotonin, and acetylcholine. Comparison of the patterns of activation of neural structures and behavior by each of these pharmacologic agents will allow us to determine whether there are multiple circuits in the subfornical organ.

水平衡的神经调节是由一个回路介导的，其中包括 室周和前脑结构。 这些结构响应 血浆和脑脊液渗透压、血管紧张素 II 和输入 来自容量和压力感受器。 本提案中概述的实验将 继续我们五年前开始的研究。 我们将检验假设 穹窿下器官（室周器官）的代谢活动 器官，通过感觉和体液输入以及多种 神经递质。 为了检验这个假设，进行了三组实验 设计：（1）我们将调查输入是否来自 压力感受器改变穹窿下器官的功能活动 对外周血管紧张素II的反应； (2) 我们将调查是否 穹窿下器官是血管紧张素II的主要作用部位；和（3） 我们将调查穹窿下器官是否对 不同的神经递质以及是否激活多个回路 他们。 主要方法将涉及放射自显影 (14C) 脱氧葡萄糖技术。 第一个问题将在 中主动脉去神经和假手术制剂。 主要站点 AII 的作用将在制剂中进行研究，其中连接 穹窿下器官和前腹侧第三脑室之间（AV3V） 区域被中断。 一些研究者指出，主要 AII 激活位点可能是 AV3V 区域。 如果血管紧张素 II 增加 受损大鼠穹窿下器官的葡萄糖利用 与假手术动物一样，这表明血管紧张素 II 穹窿下器官的刺激不依赖于 AV3V 的输入 区域。 穹窿下器官内的多重回路 通过局部刺激穹窿下检查饮酒行为 具有假定神经递质血管紧张素 II、血清素和 乙酰胆碱。 神经激活模式的比较 这些药物的结构和行为将使我们能够 以确定穹窿下器官是否存在多个回路。