Role of CAMKII in ethanol self-administration

描述(申请人提供)：酒精成瘾是一种疾病，会对人们的人际关系和生产力造成负面影响，并可能导致包括死亡在内的重大健康问题。据估计，有1760万美国人遭受酒精滥用或酒精中毒的折磨，但有效的治疗方法很少，这意味着需要更好地了解酒精如何影响哺乳动物的大脑。这项建议的目标是更好地了解调节酒精消费和复发的分子机制。人们普遍认为，饮酒会导致调节神经可塑性的细胞内信号级联反应的神经适应性变化。导致酒精寻求行为的大脑回路特别脆弱，它们的失调可能会介导与酒精成瘾相关的行为病理。大脑中一个感兴趣的区域是杏仁核，它负责调节酒精强化和与奖励相关的学习。初步数据表明，钙/钙调蛋白激酶II的α亚单位(CaMKII)是一种钙信号蛋白激酶，在C57BL/6J小鼠慢性酒精自我给药后，杏仁核中表达上调。CaMKII调节受体活性，并启动控制神经可塑性的多种转录因子，但CaMKII在酒精自我给药中的功能参与尚不清楚。本项目旨在验证酒精自我给药后CaMKII活性增加的总体假设，以及调节CaMKII活性在功能上调节酒精寻求行为的三个独立但综合的特定目标：1)利用蛋白质印迹和免疫组织化学分析来表征慢性酒精自我给药对CaMKII途径的影响；2)检查操作性酒精自我给药对CaMKII活性的影响，并通过向杏仁核内特异性地注入药理CaMKII抑制剂来确定CaMKII是否在功能上调节酒精对小鼠的增强作用；3)通过定点注射CaMKII抑制剂，确定杏仁核中的CaMKII是否在功能上调节线索诱导的酒精寻找的恢复，这是一种复发的行为模型。这些临床前实验有可能揭示一种新的分子机制，它是酒精强化和复发的基础，也是酒精成瘾的行为病理学特征。

DESCRIPTION (provided by applicant): Alcohol addiction is a disease that can negatively affect people's relationships, productivity and can lead to major health problems including death. It is estimated that 17.6 million Americans suffer from alcohol abuse or alcoholism yet there are very few effective treatments available signifying the need to better understand how alcohol affects the mammalian brain. This goal of this proposal is to better understand the molecular mechanisms that mediate alcohol consumption and relapse. It is widely accepted that alcohol consumption leads to neuroadaptive changes in intracellular signaling cascades that regulate neuroplasticity. Brain circuits that contribute to alcohol seeking behaviors are particularly vulnerable and their dysregulation may mediate behavior pathologies associated with alcohol addiction. One brain region of interest is the amygdala, which regulates alcohol reinforcement and reward- related learning. Preliminary data identified the alpha subunit of calcium/calmodulin kinase II (CAMKII) as a calcium-signaling protein kinase that is upregulated in the amygdala following chronic alcohol self- administration in C57BL/6J mice. CAMKII modulates receptor activity and initiates multiple transcription factors that control neural plasticity, yet the functional involvement of CAMKII in alcohol self-administration remains unknown. This project seeks to test the overall hypothesis that CAMKII is increased following alcohol self-administration and that modulating CAMKII activity functionally regulates alcohol-seeking behaviors in three separate but integrated specific aims: 1) to characterize the effect of chronic alcohol self- administration on the CAMKII pathway using western blot and immunohistochemical analysis; 2) to examine the effect of operant alcohol self-administration on CAMKII activity and determine if CAMKII functionally regulates the reinforcing effects of alcohol in mice using site-specific infusions of a pharmacological CAMKII inhibitor into the amygdala; and 3) to determine if CAMKII in the amygdala functionally regulates cue- induced reinstatement of alcohol-seeking, a behavioral model of relapse, using site-specific infusions of the CAMKII inhibitor. These preclinical experiments have the potential to reveal a novel molecular mechanism that underlies alcohol reinforcement and relapse, behavioral pathologies that characterize alcohol addiction.