Ethanol Remodeling of Striatal Microcircuits

纹状体微电路的乙醇重塑

• 批准号: 8729463
• 负责人: BRIAN NEIL MATHUR
• 金额: $ 21.68万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-02 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8729463
• 关键词: Acute; Alcohol abuse; Alcohol consumption; Alcohol dependence; Alcoholism; Animal Behavior; Axon; Basal Ganglia; Behavior; Behavioral; Biological Assay; Brain; Brain region; CNR1 gene; Cannabinoids; Chronic; Collaborations; Control Groups; Corpus striatum structure; Data; Depressed mood; Educational process of instructing; Endocannabinoids; Environment; Ethanol; Ethanol dependence; Foundations; Future; Generations; Grant; Habits; Human; Image; Immunohistochemistry; In Vitro; Interneurons; Knowledge; Laboratories; Learning; Long-Term Depression; Mass Spectrum Analysis; Mediating; Mentors; Mentorship; Methods; Modeling; Molecular; Mus; National Institute on Alcohol Abuse and Alcoholism; Neurons; Neurosciences Research; Operative Surgical Procedures; Output; Pathway interactions; Phase; Presynaptic Terminals; Property; Proteins; Psychological reinforcement; Public Health; Research; Research Proposals; Resources; Rewards; Role; Signal Transduction; Site; Slice; Synapses; Synaptic plasticity; System; Techniques; Testing; Toxin; Tracer; Training; Veronica; Water; Work; Writing; alcohol effect; alcohol exposure; alcohol research; anandamide; authority; behavior measurement; behavioral pharmacology; cell type; drinking; drinking behavior; effective therapy; experience; in vivo; innovation; interdisciplinary approach; millisecond; motor control; neurotransmitter release; novel therapeutics; optogenetics; post-doctoral training; presynaptic; response; responsible research conduct; skills; synaptic function; tool; transmission process

DESCRIPTION (provided by applicant): The research proposal investigates how ethanol exposure induces brain circuit remodeling to result in persistent ethanol consumption. This project will focus on a brain region that strongly controls habits, the striatum. Habit formation i dependent upon endocannabinoid signaling through the cannabinoid type 1 receptor (CB1), a presynaptic terminal protein that mediates lasting forms of synaptic plasticity. The majority of striatal CB1 is localized to inhibitory microcircuit terminals, which potently control the functionl output of this brain region. Interestingly, several lines of evidence now indicate a direct effect f ethanol on the endocannabinoid system. Despite the relevance of striatal control of habits to alcoholism, a paucity of data exists in this regard. This proposal seeks to understand how acute and chronic ethanol exposure remodels the striatal inhibitory microcircuitry to promote habitual ethanol consumption. This will be investigated through three specific experimental aims. 1) Determine the acute effects of ethanol on GABAergic transmission at specific striatal inhibitory microcircuit synapses. This aim will be accomplished by exposing acute mouse brain slices to ethanol and optogenetically assessing effects on the strength and plasticity of specific striatal inhibitory microcircuit synapses. The molecular mechanism underlying these changes will be examined by assessing the interaction between ethanol and the endocannabinoid system. 2) Assess the chronic effects of ethanol drinking in the dark (DID) on GABAergic transmission at synapses of the striatal inhibitory microcircuitry. The DID paradigm models long-term, binge-like ethanol consumption present in the human condition. To examine DID-induced lasting changes to striatal inhibitory microcircuit synapses of mice, brain slices will be made and the ethanol-induced changes to efficacy and plasticity of specific microcircuit synapses will be assessed. We will test how these maladaptive homeostatic responses of the inhibitory microcircuitry arise from ethanol-induced perturbation of the endocannabinoid system. 3) Determine the contribution of the striatal inhibitory microcircuitry to DID-induced increased ethanol consumption using in vivo optogenetics. To accomplish this aim, a specific cell type comprising the inhibitory microcircuitry will be reversibly inhibited on-line, with millisecond precision, durng drinking behavior in the DID paradigm using an optogenetics approach in vivo. The contribution of this manipulation during DID to post-DID ethanol consumatory behavior will be assessed using a two-bottle (ethanol and water) choice assay. The results of these studies should provide significant advances in our knowledge of how the reinforcing effects of ethanol are mediated by brain circuit-specific alterations. In my graduate and postdoctoral training, I gained the necessary training in neuroanatomical and electrophysiological techniques necessary to effectively execute this research proposal. In my graduate work under Dr. Ariel Y. Deutch, I trained extensively in neuroanatomical and behavioral pharmacology techniques including stereotaxic microinfusion of neuronal tract tracers and toxins, imaging mass spectrometry, immunohistochemistry, and behavioral measures of motor control. Through this training, I gained an expert ability to conceptualize brain circuitry. In my postdoctoral training under Dr. David M. Lovinger, I have become proficient in electrophysiological analyses assessing synaptic function. Moreover, I have pioneered the use of optogenetics in the lab, aided by my stereotaxic surgery abilities, for determining the contribution of synapse-specific changes to circuit remodeling. During the mentored phase of the proposal, research will be conducted at NIAAA in the laboratory of Dr. David M. Lovinger, my mentor. Dr. Andrew Holmes will serve as my co-mentor. Dr. Lovinger is an authority in ethanol and synaptic plasticity research and has extensive experience in in vitro and in vivo electrophysiological recording. Dr. Holmes, a behavioral neuroscience and ethanol research expert, will oversee my continued training in assessing animal behavior. With the combined collaboration of Dr. Veronica Alvarez and Dr. Geroge Kunos, both at NIAAA, all experimental tools and research guidance necessary for executing the research proposal will be readily accessible. Finally, the resources available at NIAAA for developing my teaching, mentorship, managerial, grant writing, and responsible conduct of research skills create a supportive environment in which to readily accomplish my proposed training plan.

描述（由申请人提供）：研究方案调查了乙醇暴露如何诱导脑回路重塑，从而导致持续的乙醇消耗。这个项目将集中在一个强烈控制习惯的大脑区域，纹状体。习惯形成依赖于通过大麻素1型受体（CB 1）的内源性大麻素信号传导，所述大麻素1型受体是介导突触可塑性的持久形式的突触前末端蛋白。纹状体CB1的大部分位于抑制性微回路末端，其有力地控制该脑区的功能输出。有趣的是，现在有几条证据表明乙醇对内源性大麻素系统有直接影响。尽管纹状体控制习惯与酗酒有关，但这方面的数据很少。这项建议旨在了解急性和慢性乙醇暴露如何重塑纹状体抑制性微电路，以促进习惯性乙醇消费。这将通过三个具体的实验目标进行研究。1)确定乙醇对特定纹状体抑制性微回路突触GABA能传递的急性效应。这一目标将通过将急性小鼠脑切片暴露于乙醇和光遗传学评估对特定纹状体抑制性微电路突触的强度和可塑性的影响来实现。这些变化的分子机制将通过评估乙醇和内源性大麻素系统之间的相互作用进行检查。 2)评估在黑暗中饮用乙醇（DID）对纹状体抑制性微电路突触处GABA能传递的慢性影响。DID范式模拟了人类条件下存在的长期、狂欢式的乙醇消耗。为了检查DID诱导的小鼠纹状体抑制性微回路突触的持久变化，将制作脑切片，并评估乙醇诱导的特定微回路突触的功效和可塑性变化。我们将测试这些适应不良的稳态反应的抑制性微电路产生乙醇诱导的内源性大麻素系统的扰动。3)使用体内光遗传学确定纹状体抑制性微电路对DID诱导的乙醇消耗增加的贡献。为了实现该目的，在DID范例中使用体内光遗传学方法在饮用行为期间，包含抑制性微电路的特定细胞类型将以毫秒级精度被可逆地在线抑制。将使用双瓶（乙醇和水）选择试验评估DID期间这种操作对DID后乙醇消耗行为的贡献。这些研究的结果应该提供了显着的进步，我们的知识，乙醇的强化效果是如何介导的脑回路特定的改变。在我的研究生和博士后培训中，我获得了有效执行这项研究计划所需的神经解剖学和电生理学技术的必要培训。我在Ariel Y博士的指导下完成了我的研究生工作。Deutch，我在神经解剖学和行为药理学技术方面接受了广泛的培训，包括神经束示踪剂和毒素的立体定位微输注、成像质谱、免疫组织化学和运动控制的行为测量。通过这次训练，我获得了一种将大脑回路概念化的专业能力。我在大卫M.洛文杰，我已经精通电生理分析评估突触功能。此外，我在实验室中率先使用光遗传学，借助我的立体定位手术能力，确定突触特异性变化对电路重塑的贡献。 在建议的指导阶段，研究将在NIAAA的大卫M博士的实验室进行。洛文杰我的导师安德鲁·霍姆斯博士将担任我的共同导师。Lovinger博士是乙醇和突触可塑性研究的权威，在体外和体内电生理记录方面拥有丰富的经验。霍姆斯博士是行为神经科学和乙醇研究专家，他将监督我在评估动物行为方面的持续培训。在NIAAA的Veronica Alvarez博士和Geroge Kunos博士的共同合作下，执行研究提案所需的所有实验工具和研究指导都将随时可用。最后，NIAAA提供的资源，用于发展我的教学，指导，管理，资助写作和负责任的研究技能，创造了一个支持性的环境，在其中很容易完成我提出的培训计划。