Central Rhythmogenesis and Behavior

描述(申请人提供)：本项目将集中于N-甲基-D-天冬氨酸(NMDA)谷氨酸受体和神经元缝隙连接共同作用的假设，以确定大脑电子耦合网络中活动的时空动力学。这一假设将在下橄榄中得到验证，下橄榄是小脑的一种主要传入神经，在成人大脑中具有最高密度的电子突触。我们实验室以前的工作表明，NMDA受体激活诱导下橄榄神经元膜电位的高阈值振荡，而连接蛋白36介导的神经元缝隙连接对于下橄榄神经元相干振荡的连续性和强度至关重要。有四个目标。目的1将确定NMDA受体是否通过作用于体内神经元缝隙连接来调节耦合网络中的电连贯性和节律。目的2将确定NMDA受体是否在体外形成电耦合的空间动力学。目的3将确定下橄榄核NMDA受体上调与低氧诱导的小脑神经元死亡之间是否存在对应关系。目的4将确定阻断下橄榄核的NMDA受体功能，或与神经元缝隙连接一起，是否能防止小脑缺氧后迟发性神经元死亡。这些目标将通过多电极记录、多光束多光子显微镜和基因转移的组合来实现，以表达具有显性-负效应的蛋白质和下橄榄中的RNA抑制物序列。近年来，下橄榄NMDA受体的上调和浦肯野细胞的死亡与婴儿猝死综合征独立相关。这项研究将确定这些临床相关现象是如何相互联系的。

DESCRIPTION (provided by applicant): This project will focus on the hypothesis that N-methyl-D-aspartate (NMDA) glutamate receptors and neuronal gap junctions act concertedly to determine the spatio-temporal dynamics of activity within electrically coupled networks in brain. The hypothesis will be tested in the inferior olive, a major afferent of the cerebellum that has the highest density of electrical synapses in the adult brain. Previous work from our laboratory showed that NMDA receptor activation induces high-threshold oscillations in membrane potential in inferior olive neurons and that neuronal gap junctions mediated by connexin36 are critical for the continuity and strength of coherent oscillations in the inferior olive. There are 4 aims. Aim 1 will determine whether NMDA receptors regulate electrical coherence and rhythm within a coupled network by acting on neuronal gap junctions in vivo. Aim 2 will determine whether NMDA receptors shape the spatial dynamics of electrical coupling in vitro. Aim 3 will determine whether there is a correspondence between NMDA receptor upregulation in the inferior olive and hypoxia-induced death of cerebellar neurons. Aim 4 will determine whether the block of NMDA receptor function in the inferior olive alone, or with neuronal gap junctions, will prevent delayed neuronal death in the cerebellum after hypoxia. These aims will be carried out with a combination of multielectrode recording, multibeam multiphoton microscopy, and gene transfer to express proteins with dominant-negative effect and RNA inhibitor sequences in the inferior olive. Recently, the upregulation of the NMDA receptor in the inferior olive and the death of Purkinje cells were independently related to sudden infant death syndrome. The research will establish how these clinically-relevant phenomena are related to one another.