Role of Class IIa HDAC Target Genes in Opioid and Cocaine Addiction

具体目标 与药物使用环境相关的外部和内部线索通常会发展成持续的和 引发吸毒复发的强大诱因。许多研究报告说，表观遗传酶，如组蛋白 脱乙酰酶(HDACs)，改变染色质结构和影响基因表达，在 动物模型中与成瘾相关的行为。在之前的资助期间，我们证明了IIa级 HDACs，HDAC5，在包括药物在内的多种可卡因诱导的行为调节中发挥重要作用 相关的学习和记忆。HDAC5靶基因Npas4作为一种重要的、新的转录 成人NAC中可卡因条件性位置偏爱和可操作性药物辨别所需因素 在小鼠静脉注射中学习自我给药。我们的初步发现表明NPAS4是被诱导的 在DARPP-32阳性的培养液中，刺状神经元(MSN)和小白蛋白阳性的快速放电中间神经元(PV- 但NPAS4调控药物行为的相关人群(S)尚不清楚。 我们的长期目标是了解NPAS4在发展和/或 与药物成瘾有关的行为的持续性。我们的中心假设是NPAS4诱导在一个或多个 更多激活的NAC神经元亚群促进谷氨酸能突触可塑性事件 持久的药物背景/线索学习和记忆。我们将采用一系列多学科的、假设 测试实验和尖端分子遗传学方法，将询问体内细胞类型- NAC中NPAS4和NPAS4表达细胞在药物成瘾中的特殊作用和调控 学习和记忆。我们将测试和完善我们的中心假设，具体目标如下： 具体目标1：确定NPAS4在获取和灭绝过程中的细胞类型特定作用 药物自我给药。在这一目标中，我们将采取细胞类型的特定功能损失和获得的方法 NPAS4在小鼠药物自我辨别和消退学习中的作用 给药试验。 特定目标2：确定NPAS4阳性的NAC神经元是否定义了一个功能“印记” 将外部线索与毒品奖励和寻找联系起来的人群。使用我们新开发的NPAS4 增强子驱动的依赖他莫昔芬的cre病毒，我们将使用化学遗传学的方法来操纵 NPAS4阳性人群的活性，并检测其在吸毒和寻求行为中的作用。 具体目标3：测定药物SA时NAC中NPAS4的细胞功能。我们将使用手机- 评估NPAS4对兴奋性广告抑制作用的类型特异性功能丧失和功能获得策略 自我给予可卡因或海洛因的小鼠的突触可塑性。

SPECIFIC AIMS External and internal cues associated with the drug use environment often develop into persistent and powerful triggers for relapse to drug seeking. Many studies have reported that epigenetic enzymes, like histone deacetylases (HDACs), that alter chromatin structure and influence gene expression play an important role in addiction-relevant behaviors in animal models. In the previous grant period, we showed that the class IIa HDACs, HDAC5, plays important roles in the regulation of multiple cocaine-induced behaviors, including drug related learning and memory. The HDAC5 target gene, Npas4, emerged as an important, novel transcription factor required in the adult NAc for cocaine conditioned place preference and operant drug discrimination learning in the mouse intravenous self-administration. Our preliminary findings indicate that NPAS4 is induced in DARPP-32-positive medium spiny neurons (MSNs) and parvalbumin-positive fast spiking interneurons (PV- FSIs), but the relevant population(s) in which NPAS4 regulates drug behaviors remains unknown. Our long-term goal is to understand the role and regulation of NPAS4 in the development and/or persistence of drug addiction-related behaviors. Our central hypothesis is that NPAS4 induction within one or more subpopulations of activated NAc neurons promotes glutamatergic synaptic plasticity events that underlie long-lasting drug context/cue learning and memory. We will employ a series of multi-disciplinary, hypothesis testing experiments and cutting-edge molecular genetic approaches that will interrogate the in vivo cell type- specific role and regulation of NPAS4 and NPAS4-expressing cells in the NAc for drug addiction-related learning and memory. We will test and refine our central hypothesis with the following specific aims: Specific Aim 1: Determine the cell-type specific roles for NPAS4 during acquisition and extinction of drug self-administration. In this aim, we will take a cell-type specific loss- and gain-of-function approaches to study the function of NPAS4 during operant discrimination and extinction learning in the mouse drug self- administration assay. Specific Aim 2: Determine whether NPAS4-positive NAc neurons define a functional “engram” population linking external cues to drug reward and seeking. Using our newly developed Npas4 enhancer-driven, tamoxifen-dependent cre virus, we will use a chemogenetic approach to manipulate the activity of the NPAS4-positive population and test its role in durg taking and seeking behaviors. Specific Aim 3: Determine the cellular function of NPAS4 in the NAc during drug SA. We will use cell- type specific loss- and gain-of-function strategies to evaluate the effects of NPAS4 on excitatory ad inhibitory synapse plasticity in mice self-administering cocaine or heroin.