Mechanisms of Alcohol Withdrawal

戒酒机制

• 批准号: 10443839
• 负责人: DWAYNE W GODWIN
• 金额: $ 42.98万
• 依托单位: WAKE FOREST UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-10 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10443839
• 关键词: Action Potentials; Address; Alcohol withdrawal syndrome; Alcohols; Animal Model; Apical; Behavior; Behavioral; Benzodiazepines; Brain; Chronic; Clinical; Complex; Coupled; Dangerousness; Data; Dendrites; Dependence; Development; Diagnosis; Dose; Drug Metabolic Detoxication; Drug Targeting; Epilepsy; Ethanol; FRAP1 gene; Grant; Hippocampus (Brain); In Vitro; Incidence; Ion Channel Protein; Knock-out; Knowledge; Lead; Longevity; Mediating; Membrane; Messenger RNA; Midline Thalamic Nuclei; Mission; Modeling; Molecular; Mouse Strains; Nature; Neurons; Organism; Outcome; Pathway interactions; Pattern; Pharmaceutical Preparations; Pharmacology; Population; Potassium Channel; Predisposition; Preparation; Prevention; Procedures; Property; Protein Synthesis Inhibitors; Proteins; Public Health; Pyramidal Cells; Research; Seizures; Signal Transduction; Sirolimus; Structure; Substance Withdrawal Syndrome; Substance abuse problem; Symptoms; Synapses; T-Type Calcium Channels; Testing; Thalamic structure; Time; Toxic effect; Translations; United States National Institutes of Health; Up-Regulation; Withdrawal; Withdrawal Symptom; Work; addiction liability; alcohol abuse therapy; alcohol effect; alcohol exposure; alcohol related problem; alcohol use disorder; drinking; experience; experimental study; gain of function; improved; in vivo; nervous system disorder; network models; neural circuit; neuronal cell body; novel; optogenetics; prevent; response; success; transmission process; voltage; voltage clamp

PROJECT SUMMARY Alcohol withdrawal (WD) produces a range of dangerous clinical symptoms, including intense seizures. Hyperexcitability underlying seizures is produced by an array of intrinsic membrane properties that are disrupted by ethanol (EtOH). Prior work has demonstrated that chronic EtOH exposure and WD produce an up-regulation of ion channel proteins and a gain of function that promotes WD seizure. A remaining gap in our understanding of WD-related seizure is a testable model that places cellular changes in a network context. WD produces upregulation and increased bursting in midline thalamic nuclei. In hippocampus, mammalian target of rapamycin Complex 1 (mTORC1) is activated in CA1 neurons during WD, represses translation of Kv1.1, and results in reduced inhibition that we hypothesize will allow invasion of thalamic bursts and increased epileptiform population discharges. We have developed a new model of network excitability that will allow us to study the emergence, time course and molecular underpinnings of EtOH WD hyperexcitability and seizure. We will address the following aims: In Aim 1, we will determine the intrinsic properties contributing to membrane hyperexcitability in midline thalamus and CA1 due to ethanol WD seizure. Using voltage clamp recordings in an in vitro preparation coupled with pharmacological approaches, we will determine whether epileptiform discharges in WD are ultimately dependent on a progressive imbalance between excitatory burst discharges in thalamus (which depend on PKC), and reduced K+ currents in CA1 pyramidal cells (which are controlled by mTOR). In Aim 2, we will Determine important regulators of dendritic excitability in thalamus and CA1 in EtOH WD seizure. mTOR signaling is implicated in the development of spontaneous seizures in epilepsy, and we show data that it is active during WD. Using molecular approaches, we will toggle mTOR activity in the presence and absence of protein synthesis inhibitors. We will test whether mTORC represses translation of Kv1.1, as suggested by our preliminary data. In Aim 3, we bring together the cellular and molecular findings to determine the effects of WD-mediated changes to network excitability and seizure susceptibility in vivo. Using a novel optogenetic approach, we will test whether stimulation of the thalamo-HC pathway during WD will elicit enhanced epileptiform activity compared to controls that will depend on patterned activity at facilitated CA1 synapses. We expect that disruptions of mTORC1 will modify or reverse WD-mediated excitability. Seizure threshold is significantly reduced during repeated EtOH WD and we will use this fact to test the hypothesis that drugs effective against WD-induced hyper-excitability will also be effective at raising seizure thresholds to baseline levels. Success in these experiments will provide a more comprehensive understanding of how brief spindle episodes and spike wave complexes promote or support tonic-clonic WD seizures – which could lead to the identification of novel pathways and associated drug targets that will provide a means to prevent WD seizure, and to more effectively treat it.

项目总结 戒酒(WD)会产生一系列危险的临床症状，包括剧烈的癫痫发作。 癫痫发作背后的超兴奋性是由一系列固有的膜特性产生的，这些特性是 被乙醇(Etoh)破坏。先前的研究表明，长期接触乙醇和WD会产生一种 上调离子通道蛋白，获得促进WD癫痫发作的功能。一个剩余的缺口 我们对WD相关癫痫的理解是一个可测试的模型，它将细胞变化置于网络中 背景。WD导致丘脑中线核团表达上调和爆发量增加。在海马体中， 哺乳动物雷帕霉素复合体靶标1(MTORC1)在WD期间激活CA1神经元，抑制 翻译Kv1.1，并导致抑制减少，我们假设将允许丘脑入侵 癫痫样放电的爆发和增加。我们开发了一种新的网络模型 兴奋性，使我们能够研究Etoh WD的出现、时间进程和分子基础 过度兴奋和癫痫。我们将解决以下目标：在目标1中，我们将确定内在的 乙醇WD引起丘脑中线和CA1细胞膜高兴奋性的特性 癫痫发作。在结合药理学方法的体外制剂中使用电压钳记录， 我们将确定WD的癫痫样放电是否最终依赖于进行性 丘脑兴奋性猝发放电(依赖于PKC)和K+电流减少之间的失衡 在CA1锥体细胞中(受mTOR控制)。在目标2中，我们将确定重要的监管机构 Etoh WD癫痫患者丘脑和CA1区树突状细胞的兴奋性MTOR信号与 癫痫自发性发作的发展，我们的数据显示，它在WD期间是活跃的。vbl.使用 分子方法，我们将在存在和不存在蛋白质合成的情况下切换mTOR活性 抑制剂。我们将测试mTORC是否像我们的初步数据所建议的那样抑制Kv1.1的翻译。 在目标3中，我们结合细胞和分子的发现来确定WD介导的效应 体内网络兴奋性和癫痫易感性的变化。使用一种新的光遗传学方法，我们将 测试在WD期间刺激丘脑-HC通路是否会引起癫痫样活动增强 与依赖于促进的CA1突触的模式活动的对照相比。我们期待着 MTORC1的破坏将改变或逆转WD介导的兴奋性。癫痫发作阈值显著 我们将利用这一事实来检验药物对以下疾病有效的假设 WD诱导的高兴奋性也将有效地将癫痫阈值提高到基线水平。在以下方面取得成功 这些实验将提供一个更全面的了解如何短暂的纺锤波发作和尖峰 波复合体促进或支持强直-克隆性WD发作-这可能导致识别新的 途径和相关的药物靶点，将提供一种手段，以防止WD发作，并更有效地 治疗它。