LOCATING GENERAL ANESTHETIC SITES IN ACETYCHOLINE RECEPTORS

乙酰胆碱受体全麻部位的定位 我们希望确定代表将军的约束地点 麻醉药作为烟碱型乙酰胆碱的抑制剂 受体(AcChoRs)。待研究的麻醉药包括类固醇，它 很可能作用于蛋白质-脂质界面，酒精和 可作用于离子通道结构域内的巴比妥酸盐，以及氟烷， 一种可能与AcChoR的新区域相互作用的挥发性麻醉剂 这对激动剂对离子通道的门控很重要。映射 将在尼古丁突触后用AcChoRs进行研究 从鱼雷电风琴中分离出的膜。带无线电标签的照片- 可激活的麻醉药将以共价方式并入AcChoRs和 标记的AcChor亚基将被分离和降解，以便 标记可以通过分析N端的蛋白质序列来确定 标记的多肽。这些结构研究提供了一个定义 AcChor的氨基酸和与之接触的区域 麻醉剂。但他们并没有评估这些产品的功能重要性 联系地点。为了解决类固醇拮抗剂的这个问题，我们将 黄体酮及其类似物相互作用的表征 野生型和突变型AcChoRs在非洲爪哇卵母细胞中的表达及鉴定 对药物效力很重要的结构决定因素以及如何确定 不同AcChoR功能区内的突变会改变药物的效力。

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.