Mechanisms of synaptic and behavioral dysfunction after postnatal anesthesia

在美国，每年有超过400万婴儿和幼儿接受全身麻醉（GA）。实验 有证据表明，一些哺乳动物物种可能患有神经退行性疾病， 认知障碍，当暴露于常见的静脉和吸入麻醉药在关键阶段， 大脑发育最近的研究还记录了GA后的睡眠-觉醒行为的破坏， 麻醉剂迄今为止，GA后观察到的行为功能障碍的潜在机制仍然存在， 尚未完全了解，早期麻醉剂暴露对突触功能的影响尚未被 详细探索。因此，本提案的长期目标是确定GA暴露如何改变 突触可塑性，突触网络和行为输出的发展海马，并破译 GA诱导的突触失调的机制。我们提出了一个特定的假设， 神经递质释放机制的组成部分，突触蛋白I，决定性地参与了神经系统疾病的病理生理学。 GA诱导的突触和认知功能障碍。该项目包括三个具体目标。在特定 目的1、探讨GA对突触前神经递质释放的影响 机械部件。这是通过几个关键组分的蛋白质印迹和qPCR定量来实现的 释放囊泡的机器在具体目标2中，我们测试了GA诱导的细胞损伤的细胞效应， 突触传递和可塑性的释放机制。这是通过系统的 基础突触传递、可塑性、兴奋性和网络的电生理学实验。在 具体目标3，我们测试麻醉剂对学习，记忆和睡眠-觉醒行为的影响，使用 巴恩斯迷宫、恐惧条件反射试验和睡眠-觉醒模式的定量脑电图分析。 总的来说，拟议的研究将提供新的理解的分子和细胞机制， GA诱导的突触失调和行为功能障碍，以及新治疗策略的基本原理 预防或改善GA后的认知、睡眠-觉醒和其他行为发育障碍 exposure.由于我的培训和研究经验，我有必要的专业知识， 开展这项工作。我召集了一批高级调查员，他们热情地参加了我的 指导和我的主席已经承诺给我受保护的时间，所有的设施和设备， 成为一名成功的转化研究科学家。我的短期目标是利用这个 奖励获得新的技能，以追求我自己的利基研究，重点是睡眠在麻醉中的作用- 诱发认知功能障碍的年轻人和老年人的大脑，以及对突触融合机制的作用 神经系统紊乱和神经传递失衡。我的长期职业目标是成为一名 独立的完全由校外资助的临床研究科学家，最终成功竞争R01 来自NIH的支持。

Over 4 million infants and young children undergo general anesthesia (GA) every year in the US. Experimental evidence suggests that several mammalian species may suffer neurodegeneration, followed by long-lasting cognitive impairment, when exposed to common intravenous and inhaled anesthetics during critical stages of brain development. Recent studies also document disruption of sleep-wake behavior following GA with volatile anesthetics. To date, the mechanisms underlying the behavioral dysfunctions observed after GA remain incompletely understood and the effects of an early anesthetic exposure on synaptic function have not been explored in detail. Thus, the long term objectives of this proposal are to establish how exposure to GA alters synaptic plasticity, synaptic networking and behavioral output in the developing hippocampus and to decipher the mechanisms of GA-induced synaptic dysregulation. We address the specific hypothesis that a key component of the neurotransmitter release machinery, synapsin I, features decisively in the pathophysiology of GA-induced synaptic and cognitive dysfunction. This project encompasses three specific aims. In Specific Aim 1, we test the molecular effects of GA on the expression of pre-synaptic neurotransmitter release machinery components. This is achieved by western blot and qPCR quantification of several key components of the machine for vesicle release. In Specific Aim 2, we test the cellular effects of GA-induced impairment of the release machinery on synaptic transmission and plasticity. This is achieved by systematic electrophysiology experiments of basal synaptic transmission, plasticity, excitability and networking. In Specific Aim 3, we test the effects of anesthetics on learning, memory and sleep-wake behavior, using the Barnes maze, fear conditioning test and quantitative electroencephalographic analysis of sleep-wake patterns. Collectively, the proposed studies will provide new understanding of the molecular and cellular mechanisms of GA-induced synaptic dysregulation and behavioral dysfunction, and the rationale for new therapeutic strategies to prevent or improve cognitive, sleep-wake and other behavioral developmental dysfunctions after GA exposure. As a result of my training and research experience, I have the expertise necessary to successfully carry out this work. I assembled a cadre of senior investigators who are participating enthusiastically in my mentoring and my Chair has committed to me the protected time, all of the facilities and equipment that are needed to develop into a successful translational research scientist. My short term objective is to use this Award to acquire new skills to pursue my own niche of research, focusing on the role of sleep in anesthesia- induced cognitive dysfunction in the young and aging brain, and on the role of the synaptic fusion mechanism in neurological disorders and imbalances of neurotransmission. My long-term career objective is to become an independent fully extramurally funded clinician research scientist by ultimately successfully competing for R01 support from the NIH.