ACTIONS AND SITES FOR LOCAL ANESTHETICS ON MEMBRANE PROTEINS

本项目的长期目标是确定 局部麻醉剂通过其产生其治疗和毒性作用。 虽然地方政府的几项主要行动 麻醉药/抗癫痫药（I类），即神经冲动阻滞， 抗过敏作用，已知是通过抑制 电压门控钠通道，这些药物不是很有选择性， 其它离子通道和功能性膜蛋白也是敏感的 给他们. 这项建议的具体目的是调查 神经细胞膜靶点的作用机制和位点 传输，具体目标：1. 进一步详细说明绑定网站，访问 局部麻醉药抑制血管生成的途径和分子机制 神经元Na通道：2.局麻药的药理学对比 直接抑制Na+通道，同时抑制K+和Ca ~（2+）通道。 3. 描述局部麻醉药对G蛋白偶联的抑制作用 神经元受体;例如Sub P.4。 使用光亲和标记， 鉴定和比较靶蛋白的那些区域， 麻醉剂结合以发挥其药理作用。 电生理（膜片钳）和生化测量 离子电流和配体结合分别用于 以LA抑制为特征。 访问并同意往返路线 离子通道将通过分别改变水溶液 粘度和膜流动性。 药理学特征将包括 药物作用对a）疏水性和膜内的依赖性 位置，B）药物电离，c）立体选择性，d）离子竞争 和e）靶蛋白的状态。 最后一个方面考虑了 电压、递质（激动剂）、G蛋白和核苷酸的能力， 和其他药物来调节目标的状态（构象 蛋白质，从而改变局部麻醉剂的作用。 很可能 在临床上用于局部区域麻醉的浓度下， 局部麻醉剂影响多种膜蛋白， 信号传输 这些研究将告诉我们这些行动 并提供临床情况的更完整描述，因此 允许更周到地设计这些药物， 程序.

The long term objectives of this project are to identify the mechanisms by which local anesthetics produce their therapeutic and toxic actions. Although several of the primary actions of local anesthetics/antiarrhythmic (ClassI), namely neuronal impulse blockage and anti-fibrillatory actions, are known to be mediated through inhibition of voltage-gated Na channels, these drugs are not very selective and other ion channels and functional membrane proteins are also susceptible to them. The specific aims of this proposal involve investigations of mechanisms and sites on membrane targets essential for neural transmission, Specific aims: 1. Further detail the binding site, access routes and molecular mechanisms for local anesthetic inhibition of neuronal Na channels: 2. Contrast the pharmacology of local anesthetic direct inhibition of Na channels with that of K+ and Ca2+ channels. 3. Characterize the inhibition by local anesthetics of G-protein coupled neuronal receptors; e.g. Sub P. 4. Use photoaffinity labeling to identify and compare those regions of the target proteins where local anesthetics bind to exert their pharmacological actions. Electrophysiological (patch-clamp) and the biochemical measurements of ionic currents and ligand binding, respectively, will be used to characterized inhibition by LAs. Access and agrees routes to and from ion channels will be investigated by separately changing aqueous viscosity and membrane fluidity. Pharmacological profiles will include dependence of action of drug on a) hydrophobicity and intra-membrane location, b) drug ionization, c) stereoselectivity, d) ion competition and e) state of the target protein. The last aspect considers the ability of voltage, transmitter (agonists), G-proteins and nucleotides, and other drugs to modulate the state (conformation) of the target protein and thereby alter the action of local anesthetics. It is likely that, at concentrations used clinically for local regional anesthesia, local anesthetics affect a variety of membrane proteins involved in signal transmission. These studies will inform us about these actions and provide a more complete description of the clinical situation, thus permitting more thoughtful design of these drugs for different procedures.