Mechanisms of Ethanol Action on NMDA Receptors and LTP

描述（由申请方提供）：N-甲基D-天冬氨酸受体（NMDAR）是诱导海马CA 1区LTP所需的离子型谷氨酸受体。在20世纪80年代，人们发现乙醇抑制这些受体并阻断LTP。乙醇抑制NMDAR和LTP的机制尚未阐明。我们以前已经表明，PKC激活剂诱导酪氨酸磷酸化和增强的NMDAR。磷酸化也是LTP诱导所必需的。我们推测乙醇的抑制作用可能是由于NMDAR亚基的酪氨酸磷酸化减少导致NMDAR的内吞作用。为了验证这些假设，我们将使用海马切片制备，免疫沉淀，和蛋白质印迹法来评估酪氨酸磷酸化的NMDA亚基后，在原位乙醇暴露。此外，我们还将利用电生理学研究NMDAR功能和LTP诱导。将采用生物化学方法评估NMDAR的表面表达。 我们希望这些研究将有助于通过增强我们对乙醇如何影响认知的知识来理解酒精中毒。

DESCRIPTION (provided by applicant): N-methyl D-aspartate receptors (NMDARs) are ionotropic glutamate receptors required for induction of LTP in area CA1 of the hippocampus. In the 1980's, it was discovered that ethanol inhibits these receptors and blocks LTP. The mechanism(s) by which ethanol inhibits NMDARs and LTP have not been elucidated. We have previously shown that PKC activators induce tyrosine phosphorylation and potentiation of the NMDAR. Phosphorylation is also required for LTP induction. We hypothesized that the inhibitory action of ethanol may be a result of reduced tyrosine phosphorylation of NMDAR subunits leading to endocytosis of NMDARs. In order to test these hypotheses, we will use the hippocampal slice preparation, immunoprecipitation, and western blotting to evaluate tyrosine phosphorylation of NMDA subunits following in situ ethanol exposure. Additionally, we will study NMDAR function and LTP induction utilizing electrophysiology. Biochemical methods will be employed to evaluate the surface expression of NMDARs. We hope that these studies will contribute to the understanding of alcoholism by enhancing our knowledge of how ethanol affects cognition.