Pathological AMPA receptor adaptations governing dependence-escalated alcohol self-administration

病理性 AMPA 受体适应控制依赖性升级的酒精自我给药

• 批准号: 10592002
• 负责人: Jessica Lea Hoffman
• 金额: $ 13.06万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10592002
• 关键词: AMPA Receptors; Address; Alcohol abuse; Alcohol consumption; Alcohol dependence; Alcohols; Amygdaloid structure; Automobile Driving; Behavior; Behavior assessment; Behavioral; Binding; Brain; Brain region; Calcium; Calcium Signaling; Chronic; Confocal Microscopy; Data; Dependence; Development; Ethanol; Fiber; Gene Expression; Genetic; Glutamates; Hippocampus; Infusion procedures; Integral Membrane Protein; Knowledge; Learning; Link; Maintenance; Measures; Medial; Mediating; Membrane; Memory; Methods; Modeling; Molecular; Mus; Nucleus Accumbens; Pathologic; Pathology; Pathway interactions; Permeability; Pharmacology; Phase; Phosphorylation; Photometry; Prefrontal Cortex; Process; Property; Prosencephalon; Proteins; Receptor Inhibition; Regulation; Resistance; Rewards; Role; Scientist; Self Administration; Severities; Site; Synaptic Transmission; Synaptic plasticity; Techniques; Testing; Training; Up-Regulation; Withdrawal; Work; alcohol abuse therapy; alcohol effect; alcohol exposure; alcohol reinforcement; alcohol response; alcohol use disorder; behavioral plasticity; brain reward regions; calmodulin-dependent protein kinase II; career; craving; drinking; excitatory neuron; experience; experimental study; genetic regulatory protein; inhibitor; innovation; insight; interdisciplinary approach; multidisciplinary; neural; neuromechanism; novel; pharmacologic; pre-clinical; preclinical study; receptor expression; receptor function; selective expression; trafficking; transmission process; vapor

Project Summary Alcohol dependence and multiple withdrawal experiences are related to increased severity of alcohol use disorder (AUD), craving, and resistance to treatment. Alcohol abuse gains control over behavior, in part, through pathological adaptations of glutamatergic AMPA receptor (AMPAR) mechanisms that regulate synaptic and behavioral plasticity in brain reward pathways. The unique auxiliary protein, transmembrane AMPAR regulatory protein (TARP) γ-8, has been shown to regulate AMPAR trafficking, activity, and CaMKII-dependent plasticity, making it critical for AMPAR mediated neural transmission. An important feature of TARP γ-8 is its highly restricted expression limited to corticolimbic regions known to regulate glutamatergic response to alcohol including the medial prefrontal cortex (mPFC), basolateral amygdala (BLA), and the hippocampus, while noticeably absent from the nucleus accumbens (NAc). Evidence indicates chronic alcohol increases glutamate levels, which in turn promotes the influx of calcium, and initiating a cascade where CaMKII phosphorylates AMPARs to increase and sustain AMPAR activity. Since AMPAR activity is required for the development of new behavior (e.g., learning) and retention of actions (e.g., memory), this fundamental neural process may underlie the development, maintenance, and critically, dependence-escalated self-administration of alcohol. Therefore, this K99/R00 proposal will determine if TARP γ-8 regulates AMPAR mediated transmission in key brain regions during dependence-escalated alcohol self-administration. Aim 1 (K99 phase) of the proposal will investigate the role of TARP γ-8 dependent excitatory Ca2+ signaling in reward-related brain regions during alcohol self- administration in the mPFC, BLA, NAc, and vHPC using a highly novel multi-spectral, four-channel fiber photometry platform. Aim 2 (K99 phase) will examine TARP γ-8 as a mechanism of CIE vapor dependence- induced escalation of alcohol self-administration and the consequential co-localization of TARP γ-8 and AMPAR using confocal microscopy. Aim 3 (R00 phase) combines these techniques to evaluate Ca2+ signaling in key- reward brain regions during dependence-escalated alcohol self-administration. These findings are then extended by taking a circuit-based approach using a selective pharmacological manipulation in combination with fiber- photometry to evaluate site-specific TARP γ-8 bound AMPAR inhibition on “bottom-up” (BLA to NAc) and “top- down” (mPFC to NAc) Ca2+ signaling. This work moves the field forward by providing fundamental mechanistic insights into TARP γ-8 dependence-escalated alcohol self-administration which has high translational value for understanding and treating AUD and has the potential to inform development of new pharmacotherapeutic strategies that target AMPAR function in a highly-selective brain region specific manner.

项目摘要 酒精依赖和多次戒断经历与酒精使用的严重程度增加有关 疾病（AUD），渴望和对治疗的抵抗。酒精滥用获得对行为的控制，部分是通过 调节突触和突触后神经元的突触能AMPA受体（AMPAR）机制的病理适应， 大脑奖励途径的行为可塑性。独特的辅助蛋白，跨膜AMPAR调节 蛋白（TARP）γ-8，已显示调节AMPAR运输、活性和CaMK II依赖性可塑性， 使其对AMPAR介导的神经传递至关重要。TARP γ-8的一个重要特征是其高度的 限制性表达局限于已知调节对酒精的兴奋性反应的皮质边缘区域 包括内侧前额叶皮质（mPFC），基底外侧杏仁核（BLA）和海马，而 明显缺乏的神经核（NAc）。有证据表明长期饮酒会增加谷氨酸盐 水平，这反过来又促进钙的流入，并启动级联反应，其中CaMKII磷酸化 增加和维持AMPAR活性。由于AMPAR活动是开发新的 行为（例如，学习）和动作的保持（例如，记忆），这个基本的神经过程可能是 酒精的发展，维持，以及关键的，依赖性升级的自我管理。因此，我们认为， 这个K99/R 00提案将确定TARP γ-8是否调节关键脑区中AMPAR介导的传递 在酒精依赖升级的自我管理过程中。该提案的目标1（K99阶段）将调查 TARP γ-8依赖性兴奋性Ca 2+信号在酒精自我调节过程中奖赏相关脑区的作用 使用高度新颖的多光谱、四通道光纤在mPFC、BLA、NAc和vHPC中进行给药 测光平台目标2（K99阶段）将检查TARP γ-8作为CIE蒸汽依赖性的机制- 酒精自我给药的诱导升级以及随之而来的TARP γ-8和AMPAR的共定位 使用共聚焦显微镜。目的3（R 00阶段）结合这些技术来评估关键细胞中的Ca 2+信号传导。 在酒精依赖升级的自我管理过程中奖励大脑区域。这些发现被延伸 通过采用基于回路的方法，使用选择性药理学操作结合纤维， 光度法来评估位点特异性TARP γ-8结合的AMPAR对“自下而上”（BLA至NAc）和“自上而下”（BLA至NAc）的抑制。 下”（mPFC至NAc）Ca 2+信号传导。这项工作通过提供基本的机械原理， 深入了解TARP γ-8依赖性-酒精自我管理升级，这对 了解和治疗AUD，并有可能为新药开发提供信息 靶向AMPAR的策略以高度选择性的大脑区域特异性方式发挥作用。