PARABRACHIAL TASTE INFLUENCE ON THE VENTRAL FOREBRAIN

在许多方面，钠的食欲与其他生物几乎没有什么不同。 动机。与性、饥饿和口渴一样，这是一种行为 表达一个更大的生理系统，它处理一个基本的 生命的问题，在这种情况下，电解质平衡。与其他产品一样 动机，食盐是由荷尔蒙驱动的，荷尔蒙产生 它们通过作用于神经元而对行为(和生理)产生很大影响 在腹侧的前脑。食盐量作为一个模型的一个优势 研究生物动机是因为它的充分刺激很简单， 钠离子，在外部环境中，这个刺激是 由单一的感官系统传递，味觉。因为神经解剖学 已经记录了味觉系统，应该有可能 跟随味觉传入信息进入大脑，并确定 它在哪里以及通过什么机制与 对相关的激素通量敏感。中概述的实验 这项提案调查了这种相互作用。前腹侧神经元 第三脑室前脑区将进行离子电泳法测试 他们对两种主要荷尔蒙的敏感性 引起食欲、醛固酮和血管紧张素II。相同 还将测试神经元对电刺激的反应性。 在臂旁核，它包含一个味觉中继器， 直接投射到腹侧的前脑。有反应的神经元 接下来，我们将检查臂旁神经刺激对 智体刺激的结果将决定神经元是否会对 对局部醛固酮浓度的变化或 血管紧张素II也直接接受来自 味觉器具。

In many respects, sodium appetite differs little from other biological motivations. As with sex, hunger, and thirst, it is the behavioral expression of a larger physiological system that deals with a fundamental problem of life, in this case electrolyte balance. As with other motivations, salt appetite is hormonally driven and the hormones produce much of their influence on behavior (and physiology) by acting on neurons in the ventral forebrain. One advantage of salt appetite as a model for studying biological motivation is that its adequate stimulus is simple, the sodium ion, and in the external environment this stimulus is transduced by a single sensory system, taste. Because the neuroanatomy of the gustatory system has been documented, it should be possible to follow gustatory afferent information into the brain and to determine where and by what mechanisms it interacts with the neural areas that are sensitive to the relevant hormone fluxes. The experiments outlined in this proposal investigate such interaction. Neurons in anteroventral third-ventricular forebrain areas will be tested iontophoretically for their sensitivity to two of the principal hormones implicated in eliciting sodium appetite, aldosterone and angiotensin II. The same neurons also will be tested for responsiveness to electrical stimulation in the parabrachial nuclei, which contains a gustatory relay that projects directly to the ventral forebrain. Neurons that respond to parabrachial stimulation, in turn, will be examined for responses to sapid stimuli, The results will determine whether neurons that respond to local changes in the concentration of either aldosterone or angiotensin II also receive direct afferent neural influence from the gustatory apparatus.