Psychostimulant Recognition by Serotonin Transporters

血清素转运蛋白对精神兴奋剂的识别

• 批准号: 7105390
• 负责人: ERIC L BARKER
• 金额: $ 22.08万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7105390
• 关键词: amines; amphetamines; antidepressants; central nervous system stimulants; cocaine; drug abuse; serotonin; serotonin transporter

DESCRIPTION (provided by applicant): The broad long-term objectives of this proposal are to identify the molecular determinants of psychostimulant recognition (cocaine and amphetamine) by serotonin transporters (SERTs), thereby revealing fundamental mechanisms involved SERT function and modulation by drugs. This project has direct health relatedness as SERTs are the molecular target for most antidepressant drugs as well as many drugs of abuse. Antidepressants such as paroxetine, fluoxetine, and imipramine bind to the transporter and inhibit serotonin uptake, thereby prolonging the extracellular lifespan of the neurotransmitter. The abused psychostimulants cocaine and amphetamine also bind to the transporter, but have distinct pharmacologic effects leading to abuse potential and possible neurotoxicity. Despite the cloning of SERT in the early 1990's, the molecular and cellular neurobiology surrounding the function of this transport protein remains to be fully elucidated. This project uses a multidisciplinary approach aimed at significantly advancing knowledge regarding the molecular pharmacology of psychostimulants at SERTs. The studies will use multiple techniques including expression and characterization of recombinant transporters in mammalian cells, the substituted cysteine accessibility method (SCAM), real-time fluorescent substrate assays, electrophysiology, and site-directed mutagenesis to identify amino acids involved with specific transporter functions including antagonist and substrate binding. In addition, computer-assisted structure-activity studies of cocaine and amphetamine derivatives will be coupled with mutagenesis in an attempt to identify direct ligand-transporter interactions. Therefore, the specific aims of this project are: 1) To determine the core domains forming the substrate permeation pathway, 2) To elucidate information about the orientation of SERT domains, and 3) To identify and elucidate the role of amino acids in the core domains involved with recognition of psychostimulants. The proposed strategies will provide critical new information linking protein structure to functional properties of the transporter and an enhanced understanding of the molecular mechanisms of action for psychotherapeutic and abused drugs. Abused stimulants such as cocaine and amphetamine (including methamphetamine ("Meth") and MDMA or 'ecstasy') are of great societal concern. The proposed studies will reveal important new information on how these abused drugs alter their target in the brain (i.e., the serotonin transporter) and offer new strategies to combat the addictive properties of these substances.

描述（由申请人提供）：该提案的广泛长期目标是确定5-羟色胺转运蛋白（SERTS）的精神刺激识别（可卡因和苯丙胺）的分子决定因素，从而揭示了药物涉及Sert功能和调节的基本机制。该项目具有直接的健康相关性，因为SERT是大多数抗抑郁药以及许多滥用药物的分子靶标。抗抑郁药，例如帕罗西汀，氟西汀和丙咪嗪与转运蛋白结合并抑制5-羟色胺摄取，从而延长神经递质的细胞外寿命。滥用的心理刺激剂可卡因和苯丙胺也与转运蛋白结合，但具有明显的药理作用，导致滥用潜力和可能的神经毒性。尽管SERT在1990年代初通过克隆，但围绕该转运蛋白功能的分子和细胞神经生物学仍有待完全阐明。该项目采用一种多学科方法，旨在显着提高有关SERTS精神刺激物分子药理学的知识。该研究将使用多种技术，包括重组转运蛋白在哺乳动物细胞中的表达和表征，取代的半胱氨酸可及性法（SCAM），实时荧光底物测定，电生理学和定位的诱变，以鉴定与特定转运蛋白有关的氨基酸，包括氨基酸，包括特定的转运蛋白功能，包括拮抗剂和二型结合。此外，可卡因和苯丙胺衍生物的计算机辅助结构活性研究将与诱变结合，以识别直接的配体转运蛋白相互作用。因此，该项目的具体目的是：1）确定形成底物渗透途径的核心结构域，2）阐明有关SERT结构域方向的信息，以及3）识别和阐明氨基酸在与识别精神刺激物识别的核心域中的作用。提出的策略将提供关键的新信息，将蛋白质结构与转运蛋白的功能特性联系起来，并增强对心理治疗和滥用药物作用的分子机制的理解。滥用可卡因和苯丙胺（包括甲基苯丙胺（“甲基”）和MDMA或'摇头丸）等受虐刺激剂非常关注。拟议的研究将揭示有关这些滥用药物如何改变其在大脑（即5-羟色胺转运蛋白）中的目标的重要新信息，并提供新的策略来打击这些物质的成瘾性。