Gene-environment interaction: the brain CRF system in alcohol preferring msP rats

摘要： 酒精中毒是一种慢性复发性疾病，随着时间的推移而发展，其特征是 从娱乐性饮酒转变为滥用和依赖。消极的情绪状态，例如 创伤性应激障碍（PTSD）或焦虑，受遗传因素影响或由环境因素决定 条件有助于形成这种过渡。另一方面，长期接触酒精是一个主要的 情绪障碍发生的决定因素（例如，焦虑、抑郁、创伤后应激障碍）和负面情绪 各州（即，烦躁、易怒）。杏仁核[杏仁核中央核（CeA）和 基底外侧杏仁核（BLA）被认为是负面情绪回路的枢纽，压力的作用 在这个大脑结构中，促肾上腺皮质激素释放因子（CRF）肽对酒精的产生和 依赖和情绪障碍/负面影响。在上一个融资期，我们提供了必要的 对CRF 1受体系统先天性过度表达、应激 超敏反应和过量乙醇消耗的遗传选择Marchigian撒丁岛（msP）大鼠。 我们最近的研究结果表明，在msP大鼠中增强的CRF信号是导致水解增加的原因。 脂肪酸酰胺水解酶（FAAH）的活性和CeA/BLA中的钝化的内源性大麻素（eCB）信号传导， 导致杏仁核中GABA和谷氨酸传输增强。我们的假设是， 这些改变有助于增强msP大鼠的应激敏感性并加重其焦虑样症状， 这可能会增加饮酒以减轻这些负面状况。通过以下方式了解机制 先天和环境因素作用/相互作用，使BLA和CeA中的CRF/eCB传输失调 将为酒精中毒的病因学提供新的见解，有助于开发新的治疗方法， 这一基本上仍未得到治疗的疾病。 这项竞争性更新的研究计划是研究如何改变eCB信号在细胞中的作用。 杏仁核由先天性（在msP大鼠中）或EtOH诱导（后依赖性Wistars）的 CRF 1系统导致过度饮酒并加剧适应不良的条件性恐惧 类似于人类PTSD的症状。FAAH恢复正常eCB功能的能力 也将研究抑制，从而抵消过量饮酒和使恐惧反应正常化。一 更好地理解msP基因型差异的分子机制， 远交Wistar大鼠和暴露于酒精后的神经适应，将提供新的见解， 先天易感性发展酒精使用障碍，并将有助于发展新的 减轻酒精依赖的治疗剂。 参与本研究的关键人员拥有完成这项工作所需的所有必要专门知识 多学科计划。特别是R博士。奇科奇奥波将监督行为实验， 节目和动物的选择。M博士罗伯托将致力于电生理学实验和 研究计划协调。Dr. L.帕森斯将进行神经化学实验， 在TSRI进行行为测试，以确保跨实验室的再现性，并提供动物用于 电生理学这三位关键人员在各自的领域都有着广泛的出版历史。 专业领域，并通过共同出版物记录持续的协作互动， 对于成功完成拟议的实验是非常宝贵的。

ABSTRACT: Alcoholism is a chronically relapsing disorder that develops over time and is characterized by the transition from recreational alcohol use to abuse and dependence. Negative emotional states, such as post- traumatic stress disorder (PTSD) or anxiety, influenced by genetic factors or determined by environmental conditions contribute to shaping this transition. On the other hand, chronic exposure to alcohol is a major determinant for the occurrence of mood disorders (e.g., anxiety, depression, PTSD) and negative emotional states (i.e., dysphoria, irritability). The amygdalar nuclei [both the central nucleus of the amygdala (CeA) and basolateral amygdala (BLA)] are considered a hub for negative emotional circuitry, and the role of the stress peptide corticotropin-releasing factor (CRF) in this brain structure is critical for both development of alcohol dependence and mood disorders/negative affect. During the previous funding period we provided essential new insight into the relationship between innate overexpression of the CRF1 receptor system, stress hypersensitivity and excessive ethanol consumption in genetically selected Marchigian Sardinian (msP) rats. Our most recent results show that enhanced CRF signaling in msP rats is responsible for increased hydrolytic activity of fatty acid amide hydrolase (FAAH) and blunted endocannabinoid (eCB) signaling in the CeA/BLA, leading to enhanced GABA and glutamate transmission in the amygdala. Our hypothesis is that such alterations contribute to enhance stress sensitivity and to exacerbate anxiety-like symptoms in the msP rats, which may increase drinking to alleviate these negative conditions. Understanding the mechanisms through with innate and environmental factors act/interact to dysregulate CRF/eCB transmission in the BLA and CeA will provide new insight into the etiopathology of alcoholism, aiding the development of new therapeutics for this still largely untreated medical condition. The research plan for this competitive renewal is to investigate how alteration of eCB signaling in the amygdala triggered by innate (in msP rats) or EtOH-induced (post-dependent Wistars) upregulation of the CRF1 system contributes to excessive alcohol drinking and exacerbates maladaptive conditioned fear responses, similar to symptoms of PTSD in humans. The ability to restore normal eCB function by FAAH inhibition, and therefore to counteract excessive drinking and normalize fear responses, will be also studied. A better understanding of the molecular mechanism underlying genotypic differences of the msP compared to outbred Wistar rats and of neuroadaptations following exposure to alcohol, will provide novel insight into the innate susceptibility to develop Alcohol Use Disorder and will be useful toward the development of new therapeutic agents to alleviate alcohol dependence. The key personnel involved in the present study possess all the necessary expertise needed to accomplish this multidisciplinary program. In particular, Dr. R. Ciccocioppo will supervise behavioral experiments, breeding programs and animal selections. Dr. M. Roberto will be dedicated to the electrophysiology experiments and the research program coordination. Dr. L. Parsons will perform the neurochemistry experiments, and will also perform behavioral tests at TSRI to ensure cross-lab reproducibility and provide the animals for electrophysiology. These three key personnel each have extensive publication histories in their respective areas of expertise, and have ongoing collaborative interactions, documented by common publications, that will be invaluable for the successful completion of the proposed experiments.