Intracellular mechanisms of cocaine-memory reconsolidation

可卡因记忆重建的细胞内机制

• 批准号: 8391346
• 负责人: Audrey M Wells
• 金额: $ 3.17万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8391346
• 关键词: Amygdaloid structure; Animal Model; Anisomycin; Antisense Oligonucleotides; Behavior; Behavioral; Brain; CREB-binding protein; CREB1 gene; Cocaine; Cocaine Dependence; Cocaine Users; Cognitive; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Cyclin-Dependent Kinase 5; Cyclin-Dependent Kinases; Data; Development; Dose; Economics; Environment; Enzymes; Extinction (Psychology); Extracellular Signal Regulated Kinases; Figs - dietary; In Vitro; Infusion procedures; Laboratories; MAP2K1 gene; MEKs; Mediating; Memory; Mitogens; Molecular; Motivation; National Research Service Awards; Pharmaceutical Preparations; Phosphotransferases; Play; Post-Translational Protein Processing; Procedures; Process; Protein Biosynthesis; Public Health; RNA Interference; Rattus; Rehabilitation therapy; Relapse; Research; Response Elements; Retrieval; Rodent Model; Role; Signal Transduction; Signaling Molecule; Small Interfering RNA; Stimulus; Techniques; Testing; Therapeutic; Time; Training; U-0126; United States; Western Blotting; Zinc Fingers; addiction; base; butyrolactone; cocaine exposure; design; drug abstinence; drug addict; drug craving; drug relapse; elk-1 protein; follow-up; human CREBBP protein; indexing; inhibitor/antagonist; insight; kinase inhibitor; long term memory; neurobiological mechanism; neuromechanism; novel; pre-doctoral; prevent; research study; response; social; sound; therapy design; therapy development; transcription factor

DESCRIPTION (provided by applicant): Environmentally-induced drug relapse is a major obstacle in the rehabilitation of cocaine users. Cocaine- associated environments maintain stimulus control over cocaine-induced behavior via context-response- cocaine associations that must be maintained in long-term memory. Thus, treatments that selectively weaken or eliminate such cocaine memories may reduce the propensity to relapse in former drug addicts. Remarkably, cocaine-related long-term memories become labile following retrieval (i.e., memory reactivation), and these memories need to be re-stabilized, or reconsolidated, into long-term storage in order to be maintained. Furthermore, evidence suggests that the basolateral amygdala (BLA) is required for the reconsolidation of cocaine memories that promote drug context-induced cocaine seeking (non-reinforced active lever presses, which provided an index of motivation for cocaine; Fuchs et al., 2009). The proposed NRSA research plan will extend this line of inquiry by exploring the intracellular mechanisms of cocaine-memory reconsolidation in the BLA with a focus on two signaling molecules: extracellular signal-related kinase (ERK) and cyclin-dependent protein kinase 5 (Cdk5). Specific aim 1 will be to test the hypothesis that ERK-mediated signaling in the BLA facilitates the reconsolidation of cocaine memories that are critical for contextual control over instrumental cocaine seeking and will explore possible downstream mechanisms of this phenomenon. Preliminary data show that intra-BLA U0126 (MEK/ERK inhibitor) treatment impairs cocaine-memory reconsolidation in a memory reactivation-dependent manner and disrupts subsequent drug context-induced cocaine seeking (Exp. 1a, in progress). These data provide sound rationale for Exp. 1b, which will utilize quantitative Western blotting to characterize changes in the activation of Elk-1, CREB, and zif268, the transcription factors that are likely activated by ERK in the BLA during memory reconsolidation (Aim 1b). As follow-up, antisense oligonucleotide or small interfering RNA manipulation will be used to assess whether the activation of Elk-1, CREB, or zif268 is required for cocaine-memory reconsolidation and subsequent contextual control over cocaine seeking. Specific aim 2 will be to test the hypothesis that Cdk5 in the BLA interferes with the reconsolidation of cocaine memories that are critical for contextual control over instrumental cocaine seeking. Based on evidence that Cdk5 negatively regulates ERK in vitro, Exp. 2 will assess whether intra-BLA ¿-butyrolactone (Cdk5 inhibitor) treatment will enhance cocaine-memory reconsolidation in a memory reactivation-dependent manner and increase subsequent drug context-induced cocaine seeking. In summary, a combination of sophisticated behavioral procedures and cutting edge molecular techniques will be used to explore the intracellular mechanisms of cocaine-memory reconsolidation, a cognitive process that maintains maladaptive addictive memories and thus stimulates environmentally-induced drug craving and relapse. This research endeavor has the potential to provide novel insights for addiction treatment development. PUBLIC HEALTH RELEVANCE: Cocaine addiction is a serious public health, social, and economic problem in the United States, in part because cocaine addicts are highly susceptible to environmentally-triggered relapse even after extended periods of drug abstinence. The experiments outlined in this predoctoral NRSA proposal will utilize a rodent model of drug relapse in order to identify novel molecular brain mechanisms that underlie the reconsolidation of cocaine-associated memories into long-term memory storage and thus the ability of these memories to drive relapse behaviors. A better understanding of such mechanisms may contribute to the development of treatments designed to weaken or abolish these memories in order to prevent drug relapse in former cocaine users.

描述（由申请人提供）：环境诱发的药物复吸是可卡因使用者康复的主要障碍。可卡因相关的环境通过情境-反应-可卡因关联来维持对可卡因诱导的行为的刺激控制，而这些情境-反应-可卡因关联必须维持在长期记忆中。因此，选择性地削弱或消除这些可卡因记忆的治疗可能会降低前吸毒者复发的倾向。值得注意的是，可卡因相关的长期记忆在检索后变得不稳定（即，记忆重新激活），并且这些记忆需要重新稳定或重新巩固到长期存储中以便维持。此外，有证据表明，基底外侧杏仁核（BLA）是促进药物情境诱导的可卡因寻求的可卡因记忆的重新巩固所必需的（非增强主动杠杆按压，其提供了可卡因的动机指数; Fuchs等人，2009年）。拟议的NRSA研究计划将通过探索BLA中可卡因记忆再巩固的细胞内机制来扩展这一调查路线，重点关注两种信号分子：细胞外信号相关激酶（ERK）和细胞周期蛋白依赖性蛋白激酶5（Cdk 5）。具体目标1将是测试的假设，ERK介导的信号在BLA促进可卡因的记忆，是关键的上下文控制工具可卡因寻求重新巩固，并将探讨这种现象可能的下游机制。初步数据显示，BLA内U 0126（MEK/ERK抑制剂）处理以记忆再激活依赖性方式损害可卡因记忆再巩固，并破坏随后的药物情境诱导的可卡因寻求（Exp. 1a，进行中）。这些数据为Exp. 1b，这将利用定量蛋白质印迹来表征Elk-1，CREB和zif 268的激活变化，这些转录因子可能在记忆再巩固期间被BLA中的ERK激活（Aim 1b）。作为后续，反义寡核苷酸或小干扰RNA操作将用于评估Elk-1、CREB或zif 268的激活是否是可卡因记忆再巩固和随后对可卡因寻求的上下文控制所需的。具体目标2将是测试的假设，Cdk 5在BLA干扰可卡因记忆的重新巩固，是关键的上下文控制工具可卡因寻求。基于Cdk 5在体外负调控ERK的证据，Exp. 2将评估BLA内丁内酯（Cdk 5抑制剂）治疗是否会以记忆再激活依赖性方式增强可卡因记忆再巩固，并增加随后的药物背景诱导的可卡因寻求。总之，复杂的行为程序和尖端分子技术的结合将用于探索可卡因记忆重新巩固的细胞内机制，这是一种维持适应不良成瘾记忆的认知过程，从而刺激环境诱导的药物渴望和复发。这项奋进可能为成瘾治疗的发展提供新的见解。 公共卫生关系：可卡因成瘾在美国是一个严重的公共卫生、社会和经济问题，部分原因是可卡因成瘾者即使在长期戒毒后也极易受到环境引发的复发的影响。NRSA博士前提案中概述的实验将利用药物复发的啮齿动物模型，以确定新的分子大脑机制，这些机制是可卡因相关记忆重新整合为长期记忆存储的基础，因此这些记忆能够驱动复发行为。更好地了解这些机制可能有助于开发旨在削弱或消除这些记忆的治疗方法，以防止前可卡因使用者复吸。