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.

项目摘要 戒酒（WD）会产生一系列危险的临床症状，包括强烈的癫痫发作。 过度刺激性癫痫发作是由一系列内在膜特性产生的 被乙醇（ETOH）破坏。先前的工作表明，慢性EtOH暴露和WD产生 离子通道蛋白的上调和促进WD癫痫发作的功能增长。剩下的差距 我们对与WD相关的癫痫发作的理解是一个可测试的模型，该模型将细胞变化置于网络中 语境。 WD在中线丘脑核中产生上调和爆发增加。在海马中， 雷帕霉素络合物1（MTORC1）的哺乳动物靶标在WD期间在CA1神经元中激活 KV1.1的翻译，并导致我们假设的抑制作用减少将允许入侵丘脑 爆发并增加了癫痫样人口排放。我们已经开发了一种新的网络模型 兴奋性将使我们能够研究ETOH WD的出现，时间过程和分子基础 过度兴奋和癫痫发作。我们将解决以下目标：在AIM 1中，我们将确定固有的 由于乙醇WD引起的中线和CA1的膜过度刺激性的特性 在体外制备中使用电压夹记录，加上药物方法， 我们将确定WD中的癫痫样放电是否最终取决于渐进性 丘脑中的兴奋性爆发放电（取决于PKC）与k+电流减少之间的不平衡 在CA1锥体细胞中（由MTOR控制）。在AIM 2中，我们将确定 thalamus和ca1的树突状兴奋性。 MTOR信号与 发育癫痫发作的发作的发展，我们显示数据在WD期间具有活性。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是否反映了我们的初步数据所建议的KV1.1的翻译。 在AIM 3中，我们将细胞和分子发现汇总在一起，以确定WD介导的影响 在体内改变网络令人兴奋性和癫痫发作的敏感性。使用一种新型的光遗传学方法，我们将 测试WD期间丘脑-HC途径的刺激是否会引起增强的癫痫表现活性 与将依赖于促进的​​CA1突触时具有图案活动的对照组相比。我们期望这一点 MTORC1的破坏将修改或反向WD介导的令人兴奋。癫痫发作阈值显着 在重复ETOH WD期间减少了 WD诱导的高启示性也将有效地将癫痫发作阈值提高到基线水平。成功 这些实验将对简短的主轴发作和尖峰有更全面的了解 波络合物促进或支持强直性WD癫痫发作，这可能导致新颖的鉴定 途径和相关的药物靶标，可以提供一种防止WD癫痫发作的方法，并更有效地 对待它。