NONCOMPETITIVE BLOCKERS OF THE ACETYLCHOLINE RECEPTOR

乙酰胆碱受体的非竞争性阻断剂

• 批准号: 2263459
• 负责人: ROBERT E OSWALD
• 金额: $ 13.57万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-08-01 至 1998-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2263459
• 关键词: Xenopus oocyte; acetylcholine; anticholinergic agent; chemical binding; molecular site; neuropharmacology; nicotinic receptors; nuclear magnetic resonance spectroscopy; protein structure function; radiotracer; receptor binding; site directed mutagenesis; tissue /cell culture

DESCRIPTION: The nicotinic acetylcholine receptor translates the binding of acetylcholine into the flow of ions across the cell membrane and thus serves a major role in the communication between two nerve cells and between nerve and muscle cells. The receptor consists of five membrane- spanning subunits which surround a central pore that functions as an ion channel. Studies of the nicotinic acetylcholine receptor are of great relevance to the understanding of neuromuscular disease due to its involvement in myasthenia gravis and related syndromes. Several classes of pharmacological and toxicological agents interact with the acetylcholine receptor, some of which activate the ion channel (agonists) and others which prevent the activation (antagonists) or block the ion channel (noncompetitive blockers). The studies described in this proposal are designed to determine the structural details of the interaction of cholinergic effectors with nicotinic acetylcholine receptors using patch clamp recording, radioligand binding, NMR spectroscopy, and site-directed mutagenesis. Two sites of interaction will be studied: the agonist binding sites and the site(s) responsible for ion channel blockade. A number of systematically varying cholinergic agonists have been synthesized for these studies and will be used to correlate the structure of the compounds with the activation and blockade of the ion channel. Single channel recording will be used to study the kinetics of the activation of the ion channel, and radioligand binding will be used to study the thermodynamic properties associated with the binding interaction. Specific mutagenesis of the receptor molecule in conjunction with systematically varying channel blockers will help the mapping the binding sites within the ion channel and possibly to probe the structure of the channel. These studies should provide important information to aid in the production of neuromuscular blockers with specific properties such as high affinity binding or long channel openings. In addition to the structure-activity and mutagenesis experiments, these investigators will exploit the power of solid state NMR spectroscopy to study the conformation of an acetylcholine derivative while bound to the nicotinic acetylcholine receptor. By using a series of three isotopically labeled compounds (13C,15N), the bound conformation can be determined by the use of the rotational-echo double-resonance NMR experiment. They hope that the combination of spectroscopic techniques with the information gained from site-directed mutagenesis and structure-activity relationships will provide a more detailed picture of the binding sites on nicotinic acetylcholine receptors and provide a basis of the rational design of drugs for this system.

描述：烟碱乙酰胆碱受体转化结合 乙酰胆碱的流入离子横跨细胞膜的流动，从而 在两个神经细胞和 在神经和肌肉细胞之间。 该受体由五个膜组成 跨越围绕中心孔的亚基，该子孔充当离子 渠道。 烟碱乙酰胆碱受体的研究非常好 与对神经肌肉疾病的理解有关 参与肌无力的肌无力和相关综合征。 几个课程 药理和毒理学剂与 乙酰胆碱受体，其中一些激活离子通道 （激动剂）和其他防止激活（拮抗剂）或 阻塞离子通道（非竞争阻滞剂）。 描述的研究 在此提案中旨在确定 胆碱能效应子与烟碱乙酰胆碱的相互作用 使用斑块夹记录，放射性配体结合，NMR的受体 光谱和定向诱变。 两个互动位点 将研究：激动剂绑定位点和负责的站点 用于离子通道封锁。 许多系统变化 胆碱能激动剂已与这些研究合成，将 用于将化合物的结构与激活相关联 和离子通道的封锁。 将使用单频道记录 研究离子通道激活的动力学，以及 放射性结合将用于研究热力学特性 与结合相互作用相关。 特定的诱变 受体分子与系统变化的通道结合 阻滞剂将帮助映射离子通道内的绑定位点 并可能探测通道的结构。 这些研究 应该提供重要信息以帮助生产 具有特定特性的神经肌肉阻滞剂，例如高亲和力 绑定或长通道开口。 除了结构活动 和诱变实验，这些研究人员将利用功率 固态NMR光谱学研究了 乙酰胆碱衍生物，同时结合到烟碱乙酰胆碱 受体。 通过使用一系列同位素标记的化合物 （13c，15n），可以通过使用 旋转回波双回应NMR实验。 他们希望 光谱技术与从中获得的信息的结合 位置定向的诱变和结构活性关系将 提供烟碱上绑定位点的更详细的图片 乙酰胆碱受体，并提供理性设计的基础 该系统的药物。