Role of Central Amygdala Astrocyte Plasticity in Ethanol Dependence

项目总结/摘要 酒精使用障碍（AUD）影响着超过1600万美国人，导致数百万可预防的死亡， 造成巨大的经济和社会负担。因此，更好地了解 AUD潜在的神经生物学机制将为开发改善的治疗方法提供见解。 战略布局酒精（乙醇）依赖是AUD的一个标志，其特征是过量饮酒， 躯体戒断症状和消极情绪杏仁核中央核（CeA）是一个关键的大脑 乙醇依赖的结构。例如，突触传递在CeA中失调， 慢性乙醇暴露后，CeA活性需要增加乙醇饮用和戒断 依赖期间的症状越来越多的证据表明，星形胶质细胞是神经细胞增殖的重要调节因子。 突触传递和行为，然而，我们缺乏对星形胶质细胞在突触传递和行为中的作用的基本理解。 酒精依赖。两个特别重要的问题是：1）慢性乙醇暴露如何影响 星形胶质细胞-神经元相互作用和2）星形胶质细胞在调节乙醇的后果中是否具有因果作用 依赖和退缩。拟议的研究将开始通过测试 长期乙醇暴露改变了CeA中星形胶质细胞-突触的接近性， 星形胶质细胞GABA转运蛋白GAT 3介导乙醇戒断和依赖性增加的乙醇摄入。 实验方法利用大鼠模型的慢性间歇性乙醇（CIE）暴露的蒸汽吸入 和酒精饮用结合超分辨率共聚焦显微镜和三维星形胶质细胞 形态分析总体假设将在以下两个具体目标中得到检验。目标1将测试 慢性乙醇暴露调节CeA中星形胶质细胞-神经元相互作用的假设。星形胶质细胞- 将在CIE暴露后评估突触接近度，以确定 星形胶质细胞可塑性星形胶质细胞-突触接近性也将在乙醇进入后进行评估， 以确定自愿饮酒如何调节依赖性和非依赖性星形胶质细胞可塑性。 依赖的老鼠目的2将检验CeA中的星形胶质细胞GAT 3调节依赖性升级的假设。 酒精摄入和身体戒断。吗啉代反义寡核苷酸策略将用于 敲低CeA中的GAT 3以确定GAT 3是否是递增的乙醇表达所必需的 酒精依赖期间的摄入和身体戒断。相反，病毒过表达策略将是 用于增加CeA中星形胶质细胞GAT 3的表达，以确定GAT 3是否足以调节 酒精摄入量和戒断率增加GAT 3操纵对星形胶质细胞可塑性的影响将 也要评估。总之，这些研究将为星形胶质细胞在乙醇中的作用提供新的见解 依赖和推进我们对潜在的神经基质的理解，这些神经基质适合于干预， 治疗AUD。

PROJECT SUMMARY/ABSTRACT Alcohol use disorder (AUD) affects over 16 million Americans, contributes to millions of preventable deaths, and causes enormous financial and societal burdens. Therefore, gaining a better understanding of the neurobiological mechanisms underlying AUD would provide insight for developing improved therapeutic strategies. Alcohol (ethanol) dependence is a hallmark of AUD that is characterized by excessive alcohol intake, somatic withdrawal symptoms, and negative mood. The central nucleus of the amygdala (CeA) is a key brain structure involved in ethanol dependence. For example, synaptic transmission is dysregulated in the CeA following chronic ethanol exposure and CeA activity is required for escalated ethanol drinking and withdrawal symptoms during dependence. Accumulating evidence suggests that astroglial cells are essential regulators of synaptic transmission and behavior, however, we lack a basic understanding regarding the role of astrocytes in in ethanol dependence. Two particularly important questions are 1) how does chronic ethanol exposure affect astrocyte-neuron interactions and 2) do astrocytes have a causal role in regulating the consequences of ethanol dependence and withdrawal. The proposed studies will begin to address these questions by testing the overarching hypothesis that chronic ethanol exposure alters astrocyte-synapse proximity in the CeA and the astrocytic GABA transporter, GAT3, mediates ethanol withdrawal and dependence-escalated ethanol intake. The experimental approach utilizes a rat model of chronic intermittent ethanol (CIE) exposure by vapor inhalation and ethanol drinking in combination with super resolution confocal microscopy and three-dimensional astrocyte morphology analysis. The overarching hypothesis will be tested in the following two specific aims. Aim 1 will test the hypothesis that chronic ethanol exposure modulates astrocyte-neuron interactions in the CeA. Astrocyte- synapse proximity will be assessed following CIE exposure to determine the temporal properties of changes in astrocyte plasticity. Astrocyte-synapse proximity will also be assessed following ethanol access during withdrawal to determine how voluntary ethanol drinking modulates astrocyte plasticity in dependent and non- dependent rats. Aim 2 will test the hypothesis that astrocytic GAT3 in the CeA regulates dependence-escalated ethanol intake and somatic withdrawal. A morpholino antisense oligonucleotide strategy will be used to knockdown GAT3 in the CeA to determine whether GAT3 is necessary for the expression of escalated ethanol intake and somatic withdrawal during ethanol dependence. In contrast, a viral overexpression strategy will be used to increase astrocytic GAT3 expression in the CeA to determine whether GAT3 is sufficient to modulate escalated ethanol intake and withdrawal. The consequences of GAT3 manipulation on astrocyte plasticity will also be assessed. Together, these studies will provide novel insight into the role of astrocytes in ethanol dependence and advance our understanding of potential neural substrates amenable to intervention for the treatment of AUD.