Molecular interactions of general anesthetics in voltage-gated sodium channels

电压门控钠通道中全身麻醉药的分子相互作用

• 批准号: 8402063
• 负责人: Annika Fitzpatrick Barber
• 金额: $ 2.51万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8402063
• 关键词: Absence of pain sensation; Adverse effects; Affect; Alanine; Amnesia; Anesthesia procedures; Anesthetics; Binding; Binding Sites; Breathing; Calculi; Clinical; Collaborations; Coupling; Dose; Electrophysiology (science); Ensure; Exhibits; Floods; Gated Ion Channel; General Anesthesia; General anesthetic drugs; Goals; Halothane; Homologous Gene; Investigation; Ion Channel; Isoflurane; Light; Maps; Mass Spectrum Analysis; Membrane; Membrane Proteins; Molecular; Monitor; Morbidity - disease rate; Muscle relaxation phase; Mutagenesis; Mutation; Nervous system structure; Neuraxis; Physiological; Property; Protein Biochemistry; Proteins; Scanning; Site; Sodium; Sodium Channel; Staging; Testing; Unconscious State; Work; base; design; interest; molecular dynamics; mortality; novel; patch clamp; patient safety; reconstitution; voltage; voltage gated channel

Despite the ubiquitous use of general anesthetics, the molecular basis of general anesthesia has yet to be elucidated. The long-term goal of this study is to shed light on the molecular basis of general anesthetic action, which may open novel opportunities to design safer general anesthetics. General anesthetics are thought to act on the central nervous system by directly interacting with membrane proteins. Since ion channels are the essence of electrical excitability in the nervous system, they are considered particularly relevant targets of general anesthetics. The central hypothesis of this proposal is that inhaled general anesthetics interact with discrete hydrophobic cavities and exert their physiological effects through allosteric coupling with an effector site involving the gating machinery of voltage-gated ion channels. This proposal investigates NaChBac, a bacterial homolog of mammalian voltage-gated sodium (Nav) channels, to characterize inhaled anesthetic interactions with voltage gated sodium channels. The aims of this project are 1) to investigate the contributions of the S4-S5 linker and the S6 segment to inhaled anesthetic action in a voltage-gated sodium, channel, and 2) to investigate the structural basis of inhaled anesthetic action in a voltage-gated sodium channel. To pursue these aims a combination of mutagenesis, patch-clamp electrophysiology, protein biochemistry, anesthetic photolabeling and molecular dynamics simulations will be used. This work will provide a stepping-stone to similar investigations of mammalian Nav channels, which are also modulated by relevant doses of inhaled anesthetics and open the door to mechanistic studies of anesthetic effects on Nav channels.

尽管全身麻醉剂的使用无处不在，但全身麻醉的分子基础尚未阐明。这项研究的长期目标是揭示全身麻醉作用的分子基础，这可能为设计更安全的全身麻醉剂提供新的机会。全身麻醉剂被认为通过直接与膜蛋白相互作用而作用于中枢神经系统。由于离子通道是神经系统电兴奋性的本质，因此它们被认为是全身麻醉药特别相关的目标。该提议的中心假设是，吸入全身麻醉剂与离散的疏水腔相互作用，并通过与涉及电压门控离子通道的门控机制的效应器位点的变构耦合发挥其生理效应。该提案研究了 NaChBac（哺乳动物电压门控钠 (Nav) 通道的细菌同源物），以表征吸入麻醉剂与电压门控钠通道的相互作用。该项目的目的是 1) 研究 S4-S5 连接体和 S6 片段对电压门控钠通道中吸入麻醉作用的贡献，以及 2) 研究电压门控钠通道中吸入麻醉作用的结构基础-门控钠通道。为了实现这些目标，将结合使用诱变、膜片钳电生理学、蛋白质生物化学、麻醉光标记和分子动力学模拟。这项工作将为哺乳动物导航通道的类似研究提供一个垫脚石，这些研究也受到相关剂量的吸入麻醉剂的调节，并为导航通道麻醉作用的机制研究打开了大门。