INBRE-2 SINGLE-CHANNEL BASIS OF MODULATION OF HUMAN NEURONAL NICOTINIC RECEPTORS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 神经元烟碱型乙酰胆碱受体将乙酰胆碱的结合转导到通道开放，从而将突触前的胞吐与突触后的兴奋联系起来。中枢神经系统中胆碱能传递的错误是阿尔茨海默病、精神分裂症、自闭症、抑郁症和尼古丁成瘾等重要疾病和疾病的基础。神经元型烟碱受体是一个不同的亚型家族，具有不同的分布和生物物理特性；然而，这些亚型的功能作用还没有被定义为正常或异常的过程。一种新的化合物，去甲酰氟溴，增强了乙酰胆碱在单一类别的尼古丁受体上的作用，因此可能用于实验和治疗。本研究的总体目标是利用单通道和快速用药方法研究去甲酰氟溴对HEK-293细胞表达的α4/β2类人神经元型烟碱受体的作用机制。神经元烟碱受体是由乙酰胆碱浓度的时间分布激活的，这取决于受体相对于胞吐部位的位置。突触外受体被相对较低的紧张性浓度的乙酰胆碱激活，而突触下受体经历高浓度(Mm)，在数百微秒的过程中变化。因此，我们将研究去甲酰氟溴对慢速和快速激动剂应用曲线激活的受体的影响。具体地说，我们的目标是确定去甲酰氟溴对1)低浓度乙酰胆碱和2)短暂(1毫秒)高浓度(1 Mm)乙酰胆碱激活的受体的影响。 尼古丁的成瘾效应是通过尼古丁对皮质边缘多巴胺系统的α4/β2受体的作用而实现的。因此，去甲酰氟溴有可能用于戒烟治疗，并可作为进一步研究α4/β2受体在尼古丁成瘾中作用的药理学工具。因此，我们将确定去甲酰氟溴对低“生理”浓度尼古丁诱导的α4/β2受体激活的影响。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Neuronal nicotinic acetylcholine receptors transduce binding of acetylcholine into channel opening, thereby linking presynaptic exocytosis with postsynaptic excitation. Errors in cholinergic transmission in the central nervous system underlie important disorders and diseases including Alzheimer's disease, schizophrenia, autism, depression and nicotine addiction. Neuronal nicotinic receptors exist as a diverse family of subtypes with distinct distributions and biophysical properties; however, the functional roles of these subtypes have not been defined for either normal or abnormal processes. A novel compound, desformylflustrabromide, potentiates the action of acetylcholine at a single class of nicotinic receptors and may therefore be of experimental and therapeutic use. The overall aim of this proposal is to use single-channel and fast drug application methods to examine the mechanism of action of desformylflustrabromide on the alpha4/beta2 class of human neuronal nicotinic receptors expressed in HEK-293 cells. Neuronal nicotinic receptors are activated by temporal profiles of acetylcholine concentration that depend on the location of the receptor relative to sites of exocytosis. Extrasynaptic receptors are activated by relatively low, tonic concentrations of acetylcholine, whereas subsynaptic receptors experience high (mM) concentrations that change over the course of hundreds of microseconds. We will therefore investigate the effects of desformylflustrabromide on receptors activated by both slow and fast agonist application profiles. Specifically, we aim to determine the effect of desformylflustrabromide on receptors activated by 1) a low concentration of acetylcholine and 2) a brief (1 ms) application of a high (1 mM) concentration of acetylcholine. The addictive effects of nicotine are mediated by the action of nicotine on alpha4/beta2 receptors of the mesocorticolimbic dopamine system. Desformylflustrabromide is therefore of potential use in smoking cessation therapy and as a pharmacological tool to investigate further the role of alpha4/beta2 receptors in nicotine addiction. We will therefore determine the effect of desformylflustrabromide on activation of alpha4/beta2 receptors induced by a low, "physiological" concentration of nicotine.