RESPONSES OF SUBPOPULATIONS OF MUSCARINIC RECEPTORS

毒蕈碱受体亚群的反应

基本信息

批准号：
3115769
负责人：
JOHN ELLIS
金额：
$ 12.56万
依托单位：
UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
依托单位国家：
美国
项目类别：
财政年份：
1985
资助国家：
美国
起止时间：
1985-02-01 至 1991-06-30
项目状态：
已结题

项目摘要

Reduced cholinergic function in the central nervous system contributes to memory disturbances, including those associated with senile dementia of the Alzheimer type. Previous studies by ourselves and others have demonstrated conclusively that distinct subtypes of muscarinic receptors are present in varying proportions in different brain regions. Classical receptor theory dictates that the most useful receptor classification schemes be based on the affinities of antagonists and several selective antagonists are now available (including pirenzepine, AF-DX 116, and quaternary antagonists). Past characterizations of muscarinic responses may have been confounded by tissue-related differences, as the different responses were studied in different tissues or preparations. This proposal intends to correlated sophisticated assays of binding and response in a model in vitro system, so as to relate the responses to given subpopulations. We will evaluate multiple muscarinic responses and receptor binding in parallel, in identical preparations (CNS neurons in primary culture); thereby, the problems of between-tissue differences will be eliminated and the affinities of a given antagonists in the different response assays and binding assays can be compared directly. The ability to generate neuronal cultures from regions of the brain that possess very different distributions of subpopulations will test the uniformity of the relationship between response and receptor subtype. The results of classical pharmacological methods, such as Schild analysis of competitive antagonists, will be supplemented by an independent procedure: selective protection of given subpopulation(s) of receptors from irreversible blockage by alkylating antagonists. Autoradiographic studies will determine whether subpopulations of muscarinic receptors are localized to specific types of (immunocytochemically identified) neurons. Studies of phosphorylation of muscarinic receptors are aimed at determining whether different subpopulations are differentially phosphorylated, desensitized, and down-regulated. The interactions of different kinases in regulating the sensitivity of the receptor(s) will also be investigated. It is expected that these studies will lead to a better understanding of the functions and regulation of different subpopulations of muscarinic receptors.

中枢神经系统中的胆碱能功能降低有助于记忆障碍，包括相关的障碍阿尔茨海默氏症类型的老年痴呆症。先前的研究我们和他人和他人最终证明了这一点毒蕈碱受体的亚型存在不同大脑区域的比例。古典受体理论决定最有用的受体分类方案是基于拮抗剂和几个选择性的亲和力现在可以使用拮抗剂（包括Pirenzepine，AF-DX 116，和第四纪拮抗剂）。毒蕈碱的过去特征响应可能与组织有关差异，因为不同的响应是在不同的组织或制剂。该建议打算关联体外模型中结合和反应的复杂测定系统，以将响应与给定的亚群相关联。我们将评估多种毒蕈碱反应和受体结合同时，在相同的制剂中（原发性的CNS神经元文化）;因此，组织之间的差异的问题将被淘汰和给定拮抗剂的亲和力可以比较不同的响应测定和约束分析直接地。从地区产生神经元文化的能力具有不同分布的大脑亚群将测试关系的均匀性在反应和受体亚型之间。古典结果药理学方法，例如竞争性的Schild分析反对者将以独立的程序补充：选择性保护受体的给定亚群免受烷基化拮抗剂不可逆地阻塞。放射自显影研究将确定毒蕈碱的亚群是否受体本地化与特定类型（免疫细胞化学鉴定）神经元。研究毒蕈碱受体的磷酸化旨在确定不同的亚群是否有差异磷酸化，脱敏和下调。这不同激酶在调节灵敏度方面的相互作用也将研究受体。预计这些研究将使对功能和调节毒蕈碱受体不同亚群。