Cerebellar Contributions to Alcohol Use Disorders

项目概要/摘要 酒精（乙醇；EtOH）滥用是导致死亡和残疾的主要原因，使我们了解 影响从健康使用 EtOH 到酒精使用障碍 (AUD) 发展的转变的机制 生物医学高度优先。在这种情况下，对社会相关浓度的最初神经反应 EtOH (5-20mM)，以及这些反应的个体差异被认为在确定 澳元发展的脆弱性或弹性。因此，识别分子靶点和神经回路至关重要 对低浓度乙醇的反应，并确定这种反应因人而异的机制 患 AUD 风险高或低的个人。在我们已发表的初步研究中，我们有 确定低浓度的 EtOH（10mM，就像普通成年人血液中的浓度一样） 饮用 1-2 个标准酒精饮料）会强烈影响小脑颗粒细胞 GABAAR 电流，但是 在具有高和低 EtOH 消耗表型的多种啮齿动物中，极性相反。 此外，我们还发现了小脑和大脑之间以前未知的直接突触连接。 腹侧被盖区（VTA），一种已知影响乙醇奖励和相关的许多方面的大脑结构 行为。这些都是重要的发现，因为小脑结构、连接性和功能的遗传差异 众所周知，对 EtOH 的敏感性与人类患 AUD 的风险以及过度摄入乙醇有关。 啮齿类动物消耗乙醇，但其潜在机制尚不清楚。该提案的目的是 增进我们对低浓度乙醇如何影响小脑时空处理的理解 行为，这些行为在具有不同 EtOH 相关行为表型的小鼠品系中如何变化，以及 表征将细胞水平的差异行为转化为差异行为的神经回路， 包括乙醇奖励和过量乙醇消耗。这项努力的成功将提高我们的 了解小脑如何影响发展 AUD 的偏好，并将识别新的 操纵对低浓度乙醇反应的分子靶标。总的来说，这些信息 应有助于指导心理和药理学方法的发展，以筛查和治疗 阻碍澳元的发展和维护。我们将使用膜片钳记录的组合 小脑脑切片、图案化光刺激（模拟体内网络处理），以及 行为技术与小脑处理的光遗传学操作相结合，以确定多低 乙醇浓度影响小脑的处理和输出以及与乙醇相关的行为。然后我们将使用 光遗传学束追踪技术可全面表征小脑至 VTA 的电路和功能，这将 提供了对神经回路的重要见解，该神经回路将小脑中 EtOH 的差异作用转化为 不同的 EtOH 相关行为表型。成功完成拟议的实验将提高 我们对影响 AUD 偏好的细胞机制和神经回路的理解。

Project Summary/Abstract Alcohol (ethanol; EtOH) abuse is a leading cause of death and disability, making our understanding of the mechanisms that affect transition from healthy use of EtOH to development of an alcohol use disorder (AUD) a high biomedical priority. In this context, the initial neurological responses to socially relevant concentrations of EtOH (5-20mM), and individual differences in those responses are thought to play a critical role in determining vulnerability or resilience to development of AUD. Thus, it is crucial to identify molecular targets and neural circuit responses to low concentrations of EtOH, and to identify the mechanisms by which such responses vary across individuals with high or low risk for developing AUD. In our published and preliminary studies, we have determined that low concentrations of EtOH (10mM, as would occur in the blood of an average adult human after consuming 1-2 standard alcoholic beverages) powerfully affect cerebellar granule cell GABAAR currents, but with opposite polarity in multiple strains of rodents with high and low EtOH consuming phenotypes respectively. Further, we have discovered a previously unknown direct synaptic connection between the cerebellum and the ventral tegmental area (VTA), a brain structure known to influence many aspects of EtOH reward and associated behaviors. These are important discoveries because genetic differences in cerebellar structure, connectivity and sensitivity to EtOH are known to be associated with risk for developing an AUD in humans and with excessive EtOH consumption in rodents, but the underlying mechanisms are unknown. The purpose of this proposal is to advance our understanding of how low concentrations of EtOH affect cerebellar spatiotemporal processing and behaviors, how such actions vary in strains of mice with divergent EtOH related behavioral phenotypes, and to characterize the neural circuitry that translates differential actions at a cellular level into differential behavior, including EtOH reward and excessive EtOH consumption. Success in this endeavor will increase our understanding of how the cerebellum influences predilection to developing an AUD, and will identify novel molecular targets for manipulating responses to low concentrations of EtOH. Collectively, such information should help guide the development of psychological and pharmacological approaches to screening for and deterring development and maintenance of AUD. We will use a combination of patch-clamp recording from cerebellar brain slices, patterned optical light stimulation (to simulate in vivo-like network processing), and behavioral techniques combined with optogenetic manipulations of cerebellar processing to determine how low concentrations of EtOH affect cerebellar processing and output, and EtOH related behaviors. We will then use optogenetic tract tracing techniques to fully characterize cerebellar to VTA circuitry and function, which will provide important insight into the neural circuitry that translates differential actions of EtOH in the cerebellum to divergent EtOH-related behavioral phenotypes. Successful completion of the proposed experiments will improve our understanding of the cellular mechanisms and neural circuitry that influences predilection to AUD.