MEMBRANE PROCESSING OF BETA ADRENORECEPTORS

β 肾上腺素受体的膜处理

• 批准号: 3286749
• 负责人: Stephen B Baker
• 金额: $ 10.32万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-05-01 至 1991-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3286749
• 关键词: 6 hydroxydopamine; adenosine triphosphate; adenylate cyclase; beta adrenergic receptor; cell membrane; corticosteroids; glycosylation; guanine nucleotide binding protein; guanine nucleotides; ion transport; laboratory rat; ligands; membrane activity; membrane permeability; membrane potentials; methylation; microtubules; protein biosynthesis; receptor coupling; tissue /cell culture

Beta-adrenergic responsiveness is dependent upon the expression of beta-adrenoreceptors. This expression will partly be dependent upon the rate of receptor synthesis, cellular processing, insertion into the plasma membrane and coupling with other components of the system and the rate of degradation. Thus any alterations in these processes may alter responsiveness. Currently, little is known about the turnover and processing of the beta- adrenoreceptor. The long-term objective of the proposed research is to characterize, with the use of irreversible receptor ligands, the relationship between the regeneration of beta- adrenoreceptors and receptor-mediated responses. Using cultured cells, the endogenous receptors are irreversibly blocked and the time course of receptor recovery is determined with respect to: antagonist binding sites (both total and cell surface), agonist high (receptor-guanine nucleotide binding protein coupling) and low affinity states, cellular localization and the ability of the receptor to mediate adenylate cyclase stimulation. The ability of various processing inhibitors and other parameters on the receptor-response recovery period will be tested. These include temperature, membrane potential, ions, ATP levels and inhibitors of protein synthesis, microtubules and glycosylation. Comparisons will be made to a rapid receptor synthesis phase in human A431 cells. After irreversible blockade in vivo, receptor recovery in atria will be determined with respect to: agonist affinity states, the ability of the receptor to mediate cyclase stimulation and atrial tension development and the beta-1 and beta-2 subtypes (several tissues). The atrial recovery studies will then be extended to conditions where it is known that receptor expression and/or responsiveness is altered. These will initially include thyroid status and denervation with 6-hydroxydopamine. Finally, it is proposed to extend some characterization studies on some novel carbostyril based beta-agonists that show either noncovalent, nondissociating or covalent binding to the receptor. Both types of compounds produce irreversible cyclase activation in vitro. The noncovalent agonists will be radiolabeled for direct agonist binding and to study receptor processign during agonist- induced internalization with the agonist attached. The alkylating irreversible agonist will be used in several receptor regeneration studies for comparison to the irreversible antagonist. The proposed studies will provide basic information on the regeneration and cellular processing of beta-adrenoreceptors and its relationship to the ability of the receptor to mediate a response. This information may point to areas where lesions could occur during disease or therapeutic interventions may be useful to alter receptor-effector coupling and receptor mediated responses.

β-肾上腺素能反应性取决于表达 β-肾上腺素受体。 这个表达式将部分依赖于 取决于受体合成、细胞加工、插入的速率 进入质膜并与其他成分偶联 系统和降解率。 因此任何改变 这些过程可能会改变响应能力。 目前，很少有 了解贝塔的营业额和加工情况 肾上腺素受体。 拟议的长期目标 研究是利用不可逆受体来表征 配体，β-再生之间的关系 肾上腺素受体和受体介导的反应。 使用培养的 细胞内，内源性受体被不可逆地阻断，并且 受体恢复的时间进程根据以下因素确定： 拮抗剂结合位点（总的和细胞表面的），激动剂高 （受体-鸟嘌呤核苷酸结合蛋白偶联）和低 亲和力状态、细胞定位和能力 介导腺苷酸环化酶刺激的受体。 的能力 各种加工抑制剂和其他参数 将测试受体反应恢复期。 这些包括 温度、膜电位、离子、ATP 水平和抑制剂 蛋白质合成、微管和糖基化。 比较 将进入人类 A431 的快速受体合成阶段 细胞。 体内不可逆阻断后，受体恢复 心房将根据以下方面确定：激动剂亲和力状态， 受体介导环化酶刺激的能力和 心房张力的发展以及 beta-1 和 beta-2 亚型 （几张纸巾）。 心房恢复研究随后将进行 扩展到已知受体表达的条件 和/或响应能力发生改变。 这些最初将包括 甲状腺状态和 6-羟基多巴胺去神经支配。 最后， 建议扩展一些特征研究 基于喹诺酮的新型 β 激动剂，显示出 与受体的非共价、非解离或共价结合。 两种类型的化合物都会产生不可逆的环化酶激活 体外。 非共价激动剂将被放射性标记用于直接 激动剂结合并研究激动剂过程中的受体过程 与连接的激动剂诱导内化。 烷基化 不可逆激动剂将用于多种受体再生 与不可逆拮抗剂进行比较的研究。 这 拟议的研究将提供有关 β-肾上腺素受体的再生和细胞加工 它与受体介导能力的关系 回复。 该信息可能指出病变可能发生的区域 发生在疾病或治疗干预期间可能有助于 改变受体-效应器耦合和受体介导的反应。