PSD protein expression in extinction of morphine-dependent conditioned behavior

描述（由申请人提供）：戒断的人类阿片类药物成瘾者复吸是阻碍阿片类药物成瘾治疗成功的主要障碍。暴露于与药物使用相关的环境线索可触发复发;因此，破坏阿片类药物与环境线索之间的习得性关联可能是减少复发和延长戒断的有效方法。海马是学习和记忆的关键神经基质，其突触可塑性是情境依赖性联想发展的一个组成部分。突触后致密区（postsynaptic density，PSD）是突触信息的接收和传递部位，基因表达的相对稳定变化与突触可塑性有关。因此，海马PSD内蛋白质表达谱的变化可能是介导突触可塑性的组成部分，突触可塑性是阿片类药物配对环境条件反应表达和消退的基础。在本提案中，我们将测试的假设，表达和灭绝的条件行为反应，以前吗啡配对的环境与差异蛋白质表达谱在海马PSD。在具体目标1中，我们将建立一个研究范式，通过重复暴露的大鼠在吗啡配对的CPP室吗啡条件性位置偏爱（CPP）的消退，在没有吗啡。在具体目标2中，我们将表征海马PSD中的蛋白质表达谱，其跟踪吗啡CPP的表达和消退。将通过同位素编码亲和标签（ICAT）和串联质谱法（LC-MS/MS）分析蛋白质表达的相对水平。在具体目标3中，我们将验证海马PSD相关蛋白的表达水平，这些蛋白被鉴定为在表达吗啡CPP的动物中与那些吗啡CPP已经熄灭的动物相比差异表达;将采用生物化学和免疫组织化学技术。灭绝后改变的蛋白质将是进一步分析药物相关条件反应灭绝机制的基础，并将为药物干预提供新的靶点，以快速有效地破坏习得的药物-环境条件关联，从而降低阿片类成瘾者复发的风险并促进戒断。阿片类药物成瘾是一种慢性、复发性行为障碍，暴露于与阿片类药物消费相关的环境“线索”会触发阿片类药物成瘾者的复发。本提案将研究与吗啡相关环境线索的行为反应中断相关的蛋白质变化，以确定开发治疗药物的新靶点，以降低阿片类成瘾者复发的风险。

DESCRIPTION (provided by applicant): Relapse to drug use in abstinent human opioid addicts is the major obstacle impeding success of opioid addiction treatment. Relapse can be triggered by exposure to environmental cues associated with drug use; as such, disruption of the learned associations between the opioid and environmental cues may be an effective approach for reducing relapse and extending abstinence. Synaptic plasticity in the hippocampus, a key neural substrate of learning and memory, is an integral component of the development of context-dependent associations. Relatively stable changes in gene expression at the postsynaptic density (PSD), which receives and transduces synaptic information, are associated with synaptic plasticity. Thus changes in the protein expression profile within the hippocampal PSD may be integral in mediating synaptic plasticity that underlies the expression and extinction of a conditioned response to an opioid-paired environment. In the present proposal, we will test the hypothesis that the expression and extinction of a conditioned behavioral response to a previously morphine-paired environment are associated with differential protein expression profiles in the hippocampal PSD. In Specific Aim 1, we will establish a paradigm for the study of extinction of morphine conditioned place preference (CPP) via repeated exposure of the rats to the previously morphine-paired CPP chambers in the absence of morphine. In Specific Aim 2, we will characterize the protein expression profiles in hippocampal PSD that track with the expression and extinction of morphine CPP. Relative levels of protein expression will be analyzed through isotope-coded affinity tag (ICAT) followed by tandem mass spectrometry (LC-MS/MS). In Specific Aim 3, we will validate the levels of expression of hippocampal PSD-associated proteins identified as being differentially expressed in animals that express morphine CPP compared to those in which morphine CPP has been extinguished; biochemical and immunohistochemical techniques will be employed. Proteins altered following extinction will be the basis for further analyses of the mechanisms of extinction of drug-associated conditioned responses, and will provide novel targets for pharmacotherapeutic intervention in the quest to rapidly and effectively disrupt learned drug-environment conditioned associations to reduce the risk of relapse and promote abstinence in opioid addicts. Opioid addiction is a chronic, relapsing behavioral disorder and exposure to environmental "cues" associated with opioid consumption triggers relapse in opioid addicts. The present proposal will examine the protein changes linked to disruption of the behavioral response to morphine-associated environmental cues in order to identify new targets for developing therapeutic medications to reduce the risk of relapse in opioid addicts.