Sex differences in neuroendocrine mechanisms of HPA axis dysfunction in alcohol use disorder

项目摘要 酒精使用障碍（AUD）是一种慢性复发性疾病，具有未满足的药理学需求， 以强迫性酒精寻求、过量摄入和消极情绪状态为特征。 下丘脑-垂体-肾上腺（HPA）轴通常协调适应性反应 在酒精依赖症中往往失调。因此，酗酒者试图 戒断者难以应对压力事件，这导致了高复发率 在这些人身上看到的。小细胞神经内分泌细胞（PNC） 下丘脑室旁核（PVN）是HPA轴的整合联系 功能，协调兴奋，抑制和内分泌信号启动HPA轴激活。 急性应激可诱导突触可塑性，表现为短时程增强（STP） 在促肾上腺皮质激素释放因子（CRF）释放的PNC上的突触。我们实验室 已经证明，从慢性间歇性乙醇治疗中退出的大鼠表现出损失 PNC中应激诱导的STP，伴随着对重复性 应力应激激素和神经递质，如CRF和去甲肾上腺素， 可能的候选人在门控应力依赖HPA轴可塑性。因此，我将进一步 在离体显微切割的PVN切片中进行全细胞膜片钳电生理学训练， 评估药物操作对酒精诱导的适应不良正常化的有效性 表型虽然男性和女性都能够在下丘脑中应激诱导STP， CRF释放PNC，潜在的性别差异尚未得到充分解决。 因此，在具体目标1中，我将评估慢性乙醇诱导的突触缺陷是否 PVN的可塑性是性别特异性的。去甲肾上腺素的输入对于启动和 保持HPA激活。因此，在具体目标2中，我将评估具体贡献 通过特异性拮抗剂（哌唑嗪和阿替美唑， 分别）的压力和乙醇诱导的PNC可塑性的变化。这些目标将共同 检验CRF和去甲肾上腺素能信号传导的性别差异是 乙醇诱导的HPA反应性不适应的差异，导致总的 在临床上观察到AUD的人群差异。我制定了一套严谨而全面的 训练方案，以实现这些电生理终点，使我能够制定一个 药理学和生理学方面的关键专业知识，通过这些知识，我可以帮助将药物 对有需要的患者进行干预。该计划得到了一个非常有能力的导师团队的支持， 协助本人在建议的奖励期内接受培训和职业发展。

Project Summary Alcohol use disorder (AUD) is a chronic relapsing disorder with unmet pharmacological needs, characterized by compulsive alcohol seeking, excessive intake, and a negative emotional state. The hypothalamic-pituitary- adrenal (HPA) axis which normally coordinates adaptive responding to stressors, is often dysregulated in alcohol dependence. Consequently, alcoholics trying to abstain have difficulty coping with stressful events which contributes to the high rates of relapse observed in these individuals. The parvocellular neuroendocrine cells (PNCs) in the paraventricular nucleus (PVN) of the hypothalamus serve as an integrative nexus for HPA axis function, coordinating excitatory, inhibitory and endocrine signals to initiate HPA axis activation. Acute stress was shown to induce synaptic plasticity in the form of short-term potentiation (STP) at glutamatergic synapses onto the corticotropin releasing factor (CRF)-releasing PNCs. Our lab has demonstrated that rats withdrawn from chronic intermittent ethanol treatment exhibit a loss of stress-induced STP in PNCs, concomitant with blunted hormonal responses to repetitive stress. Stress hormones and neurotransmitters such as CRF and norepinephrine appear as likely candidates in gating stress-dependent HPA axis plasticity. Accordingly, I will further my training in whole-cell patch clamp electrophysiology in ex vivo microdissected PVN slices to assess the efficacy of pharmacological manipulation to normalize ethanol-induced maladaptive phenotypes. While both males and females are capable of stress-induced STP in hypothalamic CRF-releasing PNCs, potential sex-differences have not been adequately addressed. Therefore, in Specific Aim 1 I will evaluate whether chronic ethanol-induced deficits to synaptic plasticity in the PVN are sex-specific. Norepinephrine inputs are critical for the initiation and maintenance of HPA activation. Thus, in Specific Aim 2 I will evaluate the specific contributions of a1 and a2 adrenergic receptors through specific antagonists (prazosin and atipamezole, respectively) to stress and ethanol-induced changes in PNC plasticity. These aims together will test the hypothesis that sex differences in CRF and noradrenergic signaling underlies differences in ethanol induced maladaptive HPA reactivity, contributing to the gross population differences seen clinically in AUD. I have developed a rigorous and thorough training regimen to achieve these electrophysiological endpoints allowing me to develop a critical expertise in pharmacology and physiology, by which I can help bring pharmaceutical interventions to patients in need. The plan is supported by a highly capable team of mentors to facilitate my training and career development under the proposed award period.