N-acetylcysteine Effects on Tetrapartite Synapses in Heroin Seeking

项目摘要/摘要 阿片成瘾是一个重大的公共卫生问题。这在一定程度上是由于缺乏非阿片类药物。 在日常使用海洛因以及使用其他滥用药物后，谷氨酸稳态调节失调 伏隔核(NAC)已被观察到，它是复发的诱因。这是一个结果 海洛因诱导的持久下调和星形胶质细胞谷氨酸转运体GLT-1摄取减少。 使用N-乙酰半胱氨酸(NAC)的临床和临床前研究表明，它是一种上调GLT-1的抗氧化剂 分别是减少对可卡因的渴望和恢复寻求海洛因的能力。恢复与海洛因有关的工作 CUES由伏核核心(NAcore)的瞬时突触增强(t-SP)调节，这是 由基质金属蛋白酶(MMPs)活性介导。然而，NAC是否抑制基质金属蛋白酶活性尚不清楚 在NAcore抑制t-SP和海洛因恢复。因此，这项提案概述了一系列实验，这些实验将 确定NAC抑制t-SP和恢复海洛因寻找是否涉及基质金属蛋白酶活性以及这是否为细胞类型 具体的。我的初步数据显示15分钟后基质金属蛋白酶活性降低(量化为积分密度 NAC(100 mg/kg/d×5天)组与生理盐水组大鼠对CUE诱导的海洛因戒断的比较 老鼠。我假设NAC在提示恢复期间会抑制NAcore中的MMP活性，这将是 依赖GLT-1。I进一步假设NAC在D1MSN附近选择性地抑制MMP9活性 在消亡过程中恢复并增强D2 MSN附近的基质金属蛋白酶-2活性。这些假设基于 根据初步数据，将通过两个具体目标进行测试。AIM 1将采用体内酶谱和GLT- 1反义吗啡策略评估NAC在海洛因恢复过程中对基质金属蛋白酶活性的影响。 Aim 2将使用细胞特异性病毒转染NAcore中的D1或D2中棘神经元(MSN)来评估 NAC处理是否选择性地影响D1MSN或D2MSN在熄灭和 恢复状态。除了了解基质金属蛋白酶信号和NAC抑制信号恢复的能力外， 这笔奖学金将训练我分析成瘾背后的突触事件的尖端技术。

PROJECT SUMMARY/ABSTRACT Opioid addiction is a major public health issue. This, in part, is due to lack of non-opioid based therapeutics. Following daily heroin use, as well as use of other drugs of abuse, dysregulation in glutamate homeostasis in nucleus accumbens (NAc) has been observed, which serves as a predisposing factor to relapse. This is a result of heroin-induced enduring down-regulation and reduced uptake by the astroglial glutamate transporter, GLT-1. Clinical and preclinical studies utilizing N-acetylcysteine (NAC), an antioxidant that upregulates GLT-1, reveal its ability to reduce cocaine craving and reinstated heroin seeking, respectively. Reinstatement to heroin-associated cues is regulated by transient synaptic potentiation (t-SP) in nucleus accumbens core (NAcore), which is mediated by activity of matrix metalloproteinases (MMPs). However, it is unknown if NAC inhibits MMP activity in NAcore to inhibit t-SP and heroin reinstatement. Hence, this proposal outlines a series of experiments that will determine if NAC inhibition of t-SP and reinstated heroin seeking involves MMP activity and if this is cell-type specific. My preliminary data indicates decreased MMP activity (quantified as integrated density) after 15 minutes of cue-induced heroin reinstatement in NAC-treated rats (100 mg/kg daily X 5 days) compared to saline-treated rats. I hypothesize that NAC will suppress MMP activity in NAcore during cued-reinstatement and this will be GLT-1 dependent. I further hypothesize NAC suppresses MMP-9 activity selectively around D1 MSNs during reinstatement and enhances MMP-2 activity adjacent to D2 MSNs during extinction. These hypotheses, based upon preliminary data, will be tested through two specific aims. Aim 1 will employ in vivo zymography and GLT- 1 anti-sense morpholino strategies to assess NAC’s effects on MMP activity during cued heroin reinstatement. Aim 2 will employ cell-specific viral transfection of D1 or D2 medium spiny neurons (MSNs) in NAcore to assess whether NAC treatment effects MMP activity selectively around D1 or D2 MSNs under extinguished and reinstated conditions. In addition to understanding MMP signaling and NAC’s ability to inhibit cued reinstatement, this fellowship will train me in cutting-edge techniques for analyzing synaptic events underlying addiction.