MOLECULAR STUDIES OF CA++ TRANSPORT IN NERVE AND RETINA

神经和视网膜 CA 运输的分子研究

• 批准号: 3288142
• 负责人: STANLEY M GOLDIN
• 金额: $ 21.59万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-09-27 至 1987-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3288142
• 关键词: axon; brain; density gradient ultracentrifugation; glutamates; immunochemistry; ion transport; membrane permeability; membrane potentials; membrane reconstitution /synthesis; neurophysiology; opiate alkaloid; radiotracer; sodium; synaptosomes

The electrical activity of the nervous system is produced by a class of protein molecules, imbedded in the nerve cell membrane, that catalyze the active pumping and passive gating of specific ions. Our laboratory has been involved in the identification, isolation, and in vitro characterization of certainkey neuronal ion transport proteins from mammalian brain: an ATP-dependent Ca ions transport system involved in the regulation of neurotransmitter release from nerve terminals, and a voltage-sensitive Na ion gate that is responsible for the neuronal "action potential." In recent years, our laboratory has developed a new approach, "transport specific fractionation," for purification of membrane transport systems. Using this technique, we have obtained purification of the neuronal Ca ions transport protein to near homogeneity (approximately 100-fold). We are now in the process of studying its possible regulation by the opiates and other endogenous mechanisms and are purifying other intraterminal Ca ions transport systems. In parallel, we have for the first time successfully reconstituted the detergent solubilized, voltage-sensitive Na ion gate and have partially purified it by "transport specific fractionation". We are proceeding to further purify it, if possible to homogeneity. We intend to incorporate vesicles containing the purified Na gate into plannar bilayers, where its electrical properties can be more quantitatively observed. We are producing monoclonal antibodies to the Na gate for immunocytochemistry. We have been studying the regulation of the Na ion gate by endogenous environmental factors.

神经系统的电活动是由一类蛋白质产生的 嵌入神经细胞膜的分子，催化活性泵送， 和特定离子的被动门控。 我们的实验室参与了 某些关键神经元鉴定、分离和体外表征 哺乳动物脑内钙离子转运蛋白：一种ATP依赖钙离子转运蛋白 参与调节神经递质从神经释放的系统 终端，和一个电压敏感的钠离子门，负责 神经元动作电位。“近年来，我们的实验室开发了一种 一种新的膜纯化方法--“转运特异性分离” 运输系统。 使用这种技术，我们已经获得了纯化的 神经元Ca离子将蛋白质转运至接近均一性（约100倍）。 我们现正研究鸦片类药物可能对它的调节作用 和其他内源性机制，并正在纯化其他端内Ca离子 运输系统。 与此同时，我们首次成功地将洗涤剂 溶解、电压敏感的Na离子门，并通过 “运输特定分馏”。 我们正在进一步净化它，如果 可能是同质性。 我们打算将含有 纯化的Na门进入平面双层，在那里它的电性能可以被 更多的定量观察。 我们正在生产抗Na+的单克隆抗体 免疫细胞化学检测。 我们一直在研究Na+的调节 离子门由内源性环境因素控制。