NEURONAL NICOTINIC ACETYLCHOLINE RECEPTORS

神经元烟碱乙酰胆碱受体

• 批准号: 3408525
• 负责人: PETER B. SARGENT
• 金额: $ 10.95万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-07-01 至 1991-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3408525
• 关键词: Anura; autonomic ganglion; bungarotoxins; denervation; electron microscopy; fresh water environment; immunochemistry; innervation; membrane activity; monoclonal antibody; neural transmission; nicotinic receptors; receptor binding; striated muscles; synapses

The long-range objective o! this research is to understand how neuronal nicotinic acetylcholine receptors (AChRs) are regulated. Our approach has been to study AChRs in a very simple and tractable system, the frog cardiac ganglion. The parasympathetic neurons in this ganglion are located in the thin interatrial septum, where they can be viewed with exceptional clarity using a variety of microscopic techniques. Ganglionic AChRs can be studied both with ACh iontophoresis and with two kinds of AChR-specific ligands: 1) cross-reacting monoclonal antibodies made against Torpedo AChRs and 2) neural-bungarotoxin (also known as 3.1 bungarotoxin, toxin F, and k-bungarotoxin), which blocks receptor function in the ganglion. The binding of these AChR-specific ligands can be visualized with fluorescence microscopy, autoradiography, and both immunoperoxidase and immunogold electron microscopy. The major questions to be addressed are: 1. What precisely is the distribution of AChRs on the surface of the ganglion cell? Are AChRs as enriched in the postsynaptic membrane of neurons as they are in skeletal muscle? 2. How does the distribution of AChRs change when neurons are denervated? Is the original distribution restored upon reinnervation? Does innervation influence AChR distribution on ganglion cells in a manner similar to that found in skeletal muscle? 3. How do results obtained with AChR-specific ligands compare with those obtained by assaying AChRs functionally via iontophoresis? The functional assay for AChR may be influenced by the presence of acetylcholinesterase on the cell surface, and this enzyme may itself be regulated by innervation. These questions represent a first step toward understanding the mechanism(s) by which AChR distribution is regulated. We also plan an initial foray into more mechanistic studies by searching for other proteins which may be important in AChR clustering on the neuronal surface and by looking for cDNA probes with which receptor expression may be studied. These studies should increase our understanding of how nicotinic AChRs on neurons are regulated. This may, in turn, lead to a better understanding of central disorders in which cholinergic function is disrupted.

远程目标o！这项研究是了解如何 调节神经元烟碱乙酰胆碱受体（ACHR）。 我们的方法是在一个非常简单且可进行的研究中研究ACHRS 系统，青蛙心脏神经节。 副交感神经元 这种神经节位于薄的隔膜中， 可以使用各种各样的清晰度查看它们 微观技术。 可以研究神经节的ACHR ACH离子噬菌体和两种ACHR特异性配体：1） 针对鱼雷ACHR的交叉反应单克隆抗体和 2）神经 - 肺毒素（也称为3.1 Bungarotoxin，毒素F， 和K-bungarotoxin），它阻断了受体功能 神经节。这些ACHR特异性配体的结合可以是 用荧光显微镜，放射自显影可视化，并且都可以看到 免疫过氧化物酶和免疫元电子显微镜。 专业 要解决的问题是： 1。在表面上的ACHR的分布是什么 神经节细胞？ 是在突触后富集的ACHR 神经元的膜是骨骼肌吗？ 2。神经元时ACHR的分布如何变化 被剥夺了？原始发行版是否还原 重新支配？神经是否影响ACHR分布在 神经节细胞的方式类似于骨骼 肌肉？ 3。与ACHR特异性配体获得的结果相比 通过通过离子噬菌体在功能上测定ACHR获得的那些？ ACHR的功能分析可能会受到的影响 细胞表面上的乙酰胆碱酯酶，该酶可能 本身受神经的调节。 这些问题是了解理解的第一步 通过调节ACHR分布的机制。 我们也计划 最初通过寻找更多机械研究的企业 其他在ACHR聚类上可能很重要的蛋白质 神经元表面并通过寻找受体的cDNA探针 可以研究表达。 这些研究应该增加我们对烟碱的理解 调节神经元的ACHR。 反过来，这可能导致 更好地了解胆碱能的中心疾病 功能被中断。