NEURONAL ACETYLCHOLINE RECEPTOR MECHANISMS

神经系统中的交流是通过信号的传输来进行的 在突触上。突触和突触的功能和调节规则 神经递质受体将在理解高等大脑方面发挥重要作用 功能。神经元烟碱型乙酰胆碱受体(AChRs)介导 整个神经系统的突触传递，但仍然很差 特色化的。鸡睫状神经节神经元提供了一个有用的系统 研究神经元AChRs。神经元表现为小电导和大电导。 Achr亚型在整个发育过程中的作用及其最新的克隆策略 已发现编码α和βAChR亚单位的基因 神经节。上一次拨款资助的研究主要集中在 AChRs在神经元上的功能、发育和调节。现在 更新将建立在这些早期研究的基础上。实验利用了 非洲爪哇卵母细胞表达系统将检测其分子基础 神经节中潜在的功能性AChR亚型。表达方式 研究将集中于比较在天然睫状体中看到的AChR特性 神经节神经元，AChRs在青蛙卵母细胞中的表达 注射编码AChR亚单位的神经节细胞mRNA。第二个大调 方向将是探索控制调控的机制 发育过程中睫状神经节神经元上的AChRs和突触 对环状AMP第二信使系统激活的反应。这个 神经元实验将提供对受体和受体途径的新见解 突触可以通过细胞间的相互作用来修改。

Communication in the nervous system takes place by transmission of signals at synapses. Rules governing the function and regulation of synapses and neurotransmitter receptors will be important in understanding higher brain functions. Neuronal nicotinic acetylcholine receptors (AChRs) mediate synaptic transmission throughout the nervous system, but remain poorly characterized. Chick ciliary ganglion neurons provide a useful system for studying neuronal AChRs. The neurons display small and large conductance AChR subtypes throughout development, and recent cDNA cloning strategies have uncovered genes encoding alpha and beta AChR subunits in the ganglion. Studies funded by the previous grant concentrated on the function, development and regulation of AChRs on the neurons. The present renewal will build on those earlier studies. Experiments utilizing the Xenopus oocyte expression system will examine the molecular basis underlying functional AChR subtypes in the ganglion. The expression studies will focus on comparing AChR properties seen in the native ciliary ganglion neurons, with AChRs expressed in frog oocytes following the injection of ganglionic mRNAs coding for AChR subunits. A second major direction will be to explore the mechanisms controlling the regulation of AChRs and synapses on ciliary ganglion neurons during development, and in response to activation of a cyclic AMP second messenger system. The neuronal experiments will provide new insights into the ways receptors and synapses can be modified by cell-cell interactions.