The role of astrocytes in emergence from volatile anesthetics

项目摘要 我们的首要目标是定义潜在的分子和细胞机制。 挥发性麻醉剂(VAS)。我们在这里提出的研究的目标是，这代表着 追求这一目标，是机械地定义星形胶质细胞的功能，而不是参与 VAS麻醉苏醒过程。我们的假设是，基于大量最近和初步的 数据显示，星形胶质细胞线粒体电子传输链(ETC)功能通过 维持星形胶质细胞钙信号、神经胶质递质释放和对神经元的代谢支持。我们 进一步假设中枢神经系统内特定的、空间上定义的星形胶质细胞群体 中枢神经系统(CNS)通过局部支持参与涌现的神经元突触来推动涌现。 我们的实验将利用纯原代星形胶质细胞培养，这是一种小鼠细胞特异性模型 通过cre介导的ETC复合体I蛋白Ndufs4的切除而破坏线粒体功能，以及 立体定向微量注射星形胶质细胞启动子驱动的重组酶靶向病毒传递 Ndufs4的脑区特异性破坏，特别是在星形胶质细胞。这些模型将使我们能够 VAS对星形胶质细胞功能的影响及参与突起的星形胶质细胞数量。具体来说， 它们将使我们能够：i)确定VAS对星形胶质细胞钙信号和线粒体功能的影响，以及 两者之间的机制联系，在体外；II)VAS对星形胶质细胞神经递质的影响 释放；iii)表征VAS对支持神经元功能的星形胶质细胞代谢物的影响；iv)定义 星形胶质细胞群体，由区域定义，负责支持VAS的麻醉苏醒。 最终，这项工作将极大地促进我们对VA活动的机制和过程的理解 浮现。 相关性 尽管VAS普遍存在，但VAS的确切目标及其多效性作用的机制， 在很大程度上是不确定的。对于成千上万的患者来说，紧急情况是每天都会发生的事情，但紧急情况发生的过程 人们对此知之甚少。出现延迟与焦虑、困惑、抵抗性活动、延迟出现 手术室，受伤风险增加，以及高昂的医疗费用。如果浮现的机制能够 如果问题得到解决，就有可能制定积极促进意识恢复的战略。

Project Summary Our overarching goal is to define the molecular and cellular mechanisms underlying the actions of volatile anesthetics (VAs). Our objective in the studies proposed here, which represent the next step in pursuing this goal, is to mechanistically define the functions of astrocytes that underly their involvement in the process of emergence from anesthesia with VAs. We hypothesize, based on substantial recent and preliminary data, astrocyte mitochondrial electron transport chain (ETC) function supports normal emergence through maintenance of astrocyte calcium signaling, gliotransmitter release, and metabolic support to neurons. We further hypothesize that specific, spatially defined, populations of astrocytes within the central nervous system (CNS) drive emergence through their local support of neuronal synapses involved in emergence. Our experiments will take advantage of pure primary astrocyte cell culture, a mouse model for cell-specific disruption of mitochondrial function through cre-mediated excision of the ETC complex I protein Ndufs4, and stereotactic microinjection targeted viral delivery of an astrocyte promoter driven cre-recombinase to enable brain region-specific disruption of Ndufs4 specifically in astrocytes. These models will allow us to characterize the astrocyte functions impacted by VAs and the population of astrocytes involved in emergence. Specifically, they will allow us to: i) define the effects of VAs on astrocyte calcium signaling and mitochondrial function, and the mechanistic links between the two, in vitro; ii) characterize the effects of VAs on astrocyte gliotransmitter release; iii) characterize the impact of VAs on astrocyte metabolites which support neuronal function; iv) define the astrocyte population, defined by region, responsible for supporting emergence from anesthesia with VAs. Ultimately, this work will greatly advance our understanding of the mechanisms of VA activity and the process of emergence. Relevance Despite their prevalence, the precise targets of VAs, and the mechanisms underlying their pleiotropic effects, are largely undefined. Emergence is a daily occurrence for thousands of patients, but the process of emergence is poorly understood. Delays in emergence are associated with anxiety, confusion, resistive activity, delays in the operating room, increased risks of injury, and significant medical costs. If the mechanisms of emergence can be resolved, it may be possible to develop strategies for active promotion of recovery of consciousness.