Pharmacology and Regulation of Nicotinic Receptor Subtypes

烟碱受体亚型的药理学和调节

• 批准号: 7561684
• 负责人: KENNETH J KELLAR
• 金额: $ 45.46万
• 依托单位: GEORGETOWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-02-01 至 2013-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7561684
• 关键词: Accounting; Acetylcholine; Adopted; Affect; Affinity; Agonist; Alzheimer' s Disease; Area; Autonomic ganglion; Autonomic nervous system; Binding; Binding Sites; Brain; Brain region; Calcium; Categories; Cell Surface Proteins; Cell membrane; Cells; Central Nervous System Diseases; Chimeric Proteins; Cholinergic Receptors; Chronic; Complex; Conotoxin; Corpus striatum structure; Dopamine; Down-Regulation; Drug abuse; Ganglia; Generic Drugs; Gilles de la Tourette syndrome; Goals; Heterogeneity; Human; Hybrids; Ions; Lead; Mammalian Cell; Methods; Myxoid cyst; Nervous system structure; Neuraxis; Neurons; Neurotransmitters; Nicotine; Nicotine Dependence; Nicotinic Receptors; Oocytes; Parkinson Disease; Pathway interactions; Permeability; Pharmacology; Physiological; Physiology; Play; Positioning Attribute; Potassium; Progress Reports; Property; Protein Subunits; Proteins; Rattus; Receptor Up-Regulation; Regulation; Role; Sodium; Structure; Testing; Tissues; Up-Regulation; base; body system; cytisine; desensitization; drug of abuse; in vivo; interest; nervous system disorder; painful neuropathy; prevent; receptor; receptor density; receptor function; response; stoichiometry; success

DESCRIPTION (provided by applicant): Our objectives are to assess the pharmacology and regulation of the diverse heteromeric neuronal nicotinic cholinergic receptor (nAChR) subtypes in the mammalian central nervous system (CNS). These receptors are widely distributed in the CNS, where they modulate release of several neurotransmitters in important neuronal pathways. Thus, they influence a wide range of functions, and they have been clearly implicated in nicotine addiction. In addition, these receptors are thought to play an important role in a wide range of other CNS disorders including Parkinson's disease, Alzheimer's disease, Tourette's syndrome and neuropathic pain. Nicotinic receptors are also crucial for normal functioning of the autonomic nervous system, and thus they influence virtually all organ systems in the body. These receptors are pentameric structures assembled from 11 subunits representing 2 classes, 1 and 2. The subunit composition of a receptor defines its subtype and determines its pharmacological and biophysical properties, which vary subtly, or not so subtly, among the particular subtypes. Two nAChR subtypes seem to form the main templates for several other heteromeric receptors found in the CNS and autonomic nervous systems. Receptors based on the 1422 subtype predominate in most areas of the CNS; whereas, the 1324 subtype provides the main template autonomic ganglia. The specific aims of the studies described in this proposal are: 1) To quantify the 142215 subtype in brain areas and determine the influence of the 15 subunit on the regulation of these receptors by nicotine; 2) To study the subunit composition, pharmacology and regulation of nAChRs containing 16 subunits; and 3) To use a powerful new method, expression of concatameric receptors consisting of all five subunits fused into a single defined receptor, to determine the properties of mixed heteromeric nAChRs of known subunit composition, stoichiometry, and subunit order. The studies described in this proposal will lead to a better understanding of important differences in the pharmacology and regulation among these different receptor subtypes and help us to understand how nicotine regulates CNS nAChRs. Nicotine is a drug of abuse that acts by binding to neuronal cell-surface proteins in the brain called nicotinic acetylcholine receptors. In addition to being involved in drug abuse, these receptors are thought to play an important role in a wide range of other disorders of the nervous system including Parkinson's disease, Alzheimer's disease, Tourette's syndrome and neuropathic pain. These nicotinic acetylcholine receptors normally are involved in transmitting information in the brain from neuron to neuron via the neurotransmitter acetylcholine. These receptors, when bound to acetylcholine or nicotine, open a channel in the membrane of the cell and allow ions such as sodium, potassium, and calcium to pass, and by so doing cause marked changes in the activity of the cells. These receptors are complexes of five separate proteins, called subunits, which come together by mutual attraction to form the functional receptor. There are two categories of receptor subunit proteins, called 1 and 2. Each of these categories has several distinct subunit proteins (e.g. 12 through 16 and 22 through 24) and a functional receptor can be generated when two copies of a specific 1 protein associates with three copies of a specific 2 protein to form what is known as a heteromeric nicotinic receptor. Because there are several different 1 and 2 subunits, the number of possible combinations is large. We, and others, have developed methods to determine which subunits actually assemble with which other subunits to form functional receptors in various brain regions. Depending on which subunits form the receptor, the pharmacological and biophysical properties are different. Aims 1 and 2 of this proposal are directed at a more complete understanding of which types of subunits assemble with each other to form nicotinic receptors. Because the properties of the most complex receptors containing more than one type of 1 and/or more than one type of 2 subunit are unknown, in Aim 3 of this proposal we have developed a method with which we can generate receptors of known subunit composition and order and then study their functional and pharmacological properties. The studies described in this proposal will lead to a better understanding of important differences in the pharmacology, physiology, and regulation among these different receptor subtypes and help us to understand how nicotine regulates its receptors in the central nervous system.

描述（由申请人提供）：我们的目标是评估哺乳动物中枢神经系统（CNS）中不同异聚神经元烟碱胆碱能受体（nAChR）亚型的药理学和调节。这些受体广泛分布在中枢神经系统中，调节重要神经元通路中几种神经递质的释放。因此，它们影响广泛的功能，并且它们显然与尼古丁成瘾有关。此外，这些受体被认为在多种其他中枢神经系统疾病中发挥着重要作用，包括帕金森病、阿尔茨海默病、抽动秽语综合征和神经性疼痛。烟碱受体对于自主神经系统的正常功能也至关重要，因此它们几乎影响体内的所有器官系统。这些受体是由代表 1 类和 2 类 2 类的 11 个亚基组装而成的五聚体结构。受体的亚基组成定义了其亚型并决定了其药理学和生物物理特性，这些特性在特定亚型之间存在微妙或不那么微妙的变化。两种 nAChR 亚型似乎形成了中枢神经系统和自主神经系统中发现的其他几种异聚受体的主要模板。基于 1422 亚型的受体在中枢神经系统的大部分区域占主导地位；而1324亚型提供了自主神经节的主要模板。该提案中描述的研究的具体目标是： 1）量化大脑区域的142215亚型并确定15亚基对尼古丁调节这些受体的影响； 2）研究16个亚基的nAChR的亚基组成、药理及调控； 3) 使用强大的新方法，表达由所有五个亚基融合成单一定义受体的多联体受体，以确定已知亚基组成、化学计量和亚基顺序的混合异聚 nAChR 的特性。该提案中描述的研究将有助于更好地理解这些不同受体亚型之间的药理学和调节方面的重要差异，并帮助我们了解尼古丁如何调节 CNS nAChR。尼古丁是一种滥用药物，通过与大脑中称为烟碱乙酰胆碱受体的神经元细胞表面蛋白结合而发挥作用。除了参与药物滥用外，这些受体还被认为在神经系统的许多其他疾病中发挥着重要作用，包括帕金森病、阿尔茨海默病、抽动秽语综合症和神经性疼痛。这些烟碱乙酰胆碱受体通常参与大脑中通过神经递质乙酰胆碱在神经元之间传递信息。这些受体与乙酰胆碱或尼古丁结合时，会在细胞膜上打开一个通道，允许钠、钾和钙等离子通过，从而引起细胞活性的显着变化。这些受体是五种独立蛋白质（称为亚基）的复合物，它们通过相互吸引聚集在一起形成功能性受体。受体亚基蛋白有两类，称为 1 和 2。每一类都有几个不同的亚基蛋白（例如 12 至 16 和 22 至 24），当特定 1 蛋白的两个拷贝与特定 2 蛋白的三个拷贝结合形成所谓的异聚烟碱受体时，可以生成功能性受体。由于存在多个不同的 1 和 2 亚基，因此可能的组合数量很大。我们和其他人已经开发出方法来确定哪些亚基实际上与哪些其他亚基组装以形成不同大脑区域的功能受体。根据形成受体的亚基的不同，药理学和生物物理特性也不同。该提案的目标 1 和 2 旨在更全面地了解哪些类型的亚基相互组装形成烟碱受体。由于包含多于一种类型的 1 和/或多于一种类型的 2 亚基的最复杂受体的特性尚不清楚，因此在本提案的目标 3 中，我们开发了一种方法，通过该方法我们可以生成已知亚基组成和顺序的受体，然后研究其功能和药理学特性。该提案中描述的研究将有助于更好地理解这些不同受体亚型之间的药理学、生理学和调节方面的重要差异，并帮助我们了解尼古丁如何调节中枢神经系统中的受体。