SYNAPTIC BASIS FOR CENTRAL AUTONOMIC INTEGRATION

参与内脏神经自主反应的一级神经元 刺激位于孤束核（NTS）， 最后区，位于血脑屏障外的脑室周围器官。 对循环激素和压力的综合自主反应， 情绪事件也很可能部分地通过传入 对NTS的预测。 这些后者的传入分别来自（1） 从最后区，和（2）从前脑区域，如 前额叶皮层（PFC）和杏仁核中央核。 前和/或 突触后递质特异性靶点和 这些传入神经的非靶神经元可能在 自主反射的调节。 这些互动中的大多数 尚未通过双标记电子显微镜建立 免疫细胞化学 因此，拟议研究I的目标是使用这些 方法来确定在大鼠NTS和最后区是否有一个 神经元之间相互作用的结构基础， 神经递质和/或肽参与自主调节。 这些包括：通过免疫反应性鉴定的 合成酶、酪氨酸羟化酶和苯乙醇胺 N-甲基转移酶;通过产物或其合成鉴定的GABA 酶，谷氨酸脱羧酶;内源性阿片肽和 神经肽Y拟议研究II和III的目标是确定 使用示踪和电子显微镜免疫细胞化学（1） 是否有来自迷走神经的会聚传入输入到NTS 来自最后区、PFC或杏仁核的传入和传入;以及， 如果是，（2）这些收敛是否发生在包含以下之一的神经元上： 研究I中确定的假定递质。此外，在研究 II定量光镜免疫细胞化学和原位 杂交将被用来确定是否内脏的变化， 传入神经改变神经递质相关产物的检测水平 或者它们在NTS中相应的mRNA。 这些发现将进一步促进我们的 了解传入自主神经的结构和化学基础 在大鼠背迷走神经复合体水平的调节。 更 重要的是，这些研究可以提供与我们的 理解自主神经的细胞机制 精神分裂症等神经精神疾病的异常 比如人类的焦虑和恐慌症。

The first order neurons involved in autonomic responses to visceral stimulation are located in the nuclei of the solitary tracts (NTS) and area postrema, a circumventricular organ outside the blood-brain barrier. Integrated autonomic responses to circulating hormones and stress or emotional events are also most likely partially mediated through afferent projections to the NTS. These latter afferents derive respectively (1) from the area postrema, and (2) from forebrain regions such as the prefrontal cortex (PFC) and central nucleus of the amygdala. Pre- and/or postsynaptic interactions between transmitter-specific target and non-target neurons of these afferents are likely to play key roles in modulation of autonomic reflexes. The majority of these interactions have not been established by dual labeling electron microscopic immunocytochemistry. Thus, the goal of proposed Study I is to use these methods to determine in the rat NTS and area postrema whether there is a structural basis for interactions among neurons containing specific transmitters and/or peptides most implicated in autonomic regulation. These include: catecholamines identified by immunoreactivity for the synthesizing enzymes, tyrosine hydroxylase and phenylethanolamine N-methyl transferase; GABA identified by the product or its synthesizing enzyme, glutamic acid decarboxylase; endogenous opiate peptides and neuropeptide Y. The goals of proposed Studies II and III are to determine using tract-tracing and electron microscopic immunocytochemistry (1) whether there is converging afferent input to the NTS from vagal afferents and afferents either from area postrema, PFC or amygdala; and, if so (2) whether these convergences occur on neurons containing one of the putative transmitters identified in Study I. Additionally, in Study II quantitative light microscopic immunocytochemistry and in situ hybridization will be used to determine whether changes in visceral afferents alter the detected levels of neurotransmitter related products or their corresponding mRNA's in the NTS. The findings will further our understanding of the structural and chemical basis for afferent autonomic regulation at the level of the dorsal vagal complex in the rat. More importantly, these studies may provide information relevant to our understanding of the cellular mechanisms underlying autonomic abnormalities in neuropsychiatric illnesses such as schizophrenia as well as in anxiety and panic disorders in human.