LOCATING GENERAL ANESTHETIC SITES IN ACETYCHOLINE RECEPTORS

乙酰胆碱受体定位全身麻醉部位 我们希望确定一般代表的约束力的网站 用作烟碱乙酰胆碱抑制剂的麻醉剂 受体（AcChoRs）。待研究的麻醉剂包括类固醇， 可能作用于蛋白质-脂质界面，醇类和 巴比妥酸盐，其可在离子通道结构域内起作用，以及氟烷， 一种可能与AcChoR新区域相互作用的挥发性麻醉剂 对于激动剂对离子通道的门控很重要。映射 将在烟碱突触后神经元中用AcChoR进行研究。 从电鳐的发电器官中分离出膜。放射性标记，照片- 可活化的麻醉剂将共价结合到AcChoR中， 标记的AcChor亚基将被分离和降解， 标记可以通过N-末端蛋白质序列分析来确定。 标记肽。这些结构研究提供了一个定义， AcChor的氨基酸和区域与AcChor的氨基酸和区域接触， 麻醉剂但他们没有评估这些功能的重要性， 接触点。为了解决类固醇拮抗剂的问题，我们将 表征孕酮和孕酮类似物与 在非洲爪蟾卵母细胞中表达的野生型和突变型AcChoR，以鉴定 结构决定因素对药物效力的重要性，并确定如何 不同AcChoR功能结构域内的突变改变药物效力。

Locating General Anesthetic Sites in Acetylcholine Receptors We wish to identify the sites of binding of representative general anesthetics when they are acting as inhibitors of nicotinic acetylcholine receptors (AcChoRs). The anesthetics to be studied include steroids, which are likely to act at the protein-lipid interface, alcohols and barbiturates, that may act within the ion channel domain, and halothane, a volatile anesthetic that may interact with novel regions of the AcChoR that are important for the gating of the ion channel by agonists. Mapping studies will be carried out with AcChoRs in nicotinic postsynaptic membranes isolated from Torpedo electric organ. Radio-labeled, photo- activatable anesthetics will be covalently incorporated into AcChoRs and labeled AcChor subunits will be isolated and degraded so that the sites of labeling can be determined by N-terminal protein sequence analysis of the labeled peptides. These structural studies provide a definition of the amino acids and regions of the AcChor that tare in contact with the anesthetics. but they do not assess the functional importance of these sites of contact. To address this for steroid antagonists, we will characterize interactions of progesterone and progesterone analogs with wild type and mutant AcChoRs expressed in Xenopus oocytes to identify structural determinants important for drug potency and to determine how mutations within different AcChoR functional domains alter drug potency.