Role of Lateral Hypothalmic Area Perineuronal Nets in the Reinstatement of Cocaine-Seeking Behavior

摘要 物质使用障碍和随后的复发是由于长期或永久性的 动机行为的神经回路(药物诱导的神经可塑性)。我最近的研究发现了一个 下丘脑外侧区(LHA)，它对可卡因诱导的行为起关键作用，但 到目前为止，它在药物成瘾中的作用尚不清楚。这一地区的引人注目之处在于它被厚厚的 特殊的细胞外基质结构称为神经周围神经网络(PNNS)。PNN是一种新兴的 预防药物诱导的神经可塑性的有希望的目标，因为它们的去除深刻地改变了 可卡因的神经可塑性。我最近的研究发现并定义了背部和 LHA前部中间带(LHAad/I)周围PNNS表达显著增强 我发现GABA能神经元对可卡因--但不是蔗糖诱导的行为--是关键的。这个 LHAad/i接收来自前额叶皮质(PL PFC)的输入，并将投射发送到VTA。普莱 PFC和VTA是动机行为的中皮质边缘回路的主要组成部分，并密切相关 与吸毒复发有关。LHAAD/I在此电路中的作用尚未研究，但已 重要的是参与了寻找可卡因的行为。值得注意的是，它不是更深入研究的地区的一部分 下丘脑外侧区。我已经确定这些PNN对可卡因的获取至关重要--但是 非蔗糖诱导的行为和线索诱导的可卡因寻找的恢复。在这里，我建议测试一下 三个具体目标中的三个假说，重点是预防 去除LHAad/I PNN诱导的可卡因行为。特定目标1(K99阶段)将检验以下假设 去掉LHAad/i PNN将增加VTA DA神经元的突触前GABA输入。我将接受正式的体外训练 电生理和光刺激VTA内的LHAad/I终末以确定LHAad/I PNN的影响 去除对VTA神经元突触传递的影响。我将在K99阶段的最后部分开始具体的目标2。 特异靶2(K99和R00期)将检验LHAad/I神经元的化学生成激活是否 VTA的项目将阻止线索诱导的可卡因寻找的恢复。我将继续我的使用培训 利用先进的病毒载体化学激活投射到VTA的LHAad/I神经元。特定目标3(R00 句点)将检验去除LHAad/i PNN将减少PL PFC谷氨酸输入到LHAad/i的假设 神经元。PL PFC投射到LHAad/i将受到光基因刺激。这一目标将被实现 在R00期间的第四年和第五年独立地应用我在K99期间所接受的培训。中心到 成功的长期复发预防需要修改可卡因诱导的新靶点 动机行为回路中的可塑性。拟议的培训是PI成功的基础 从博士后过渡到独立的终身教职。

Abstract Substance use disorders and subsequent relapse occurs as a result of long-term or permanent changes in the neurocircuitry of motivated behavior (drug-induced neuroplasticity). My recent studies have uncovered a discrete region of the lateral hypothalamus (LHA) that critically contributes to cocaine-induced behaviors, but its role in drug addiction was unknown until now. This region is striking in that it is heavily wrapped in a specialized extracellular matrix structures called perineuronal nets (PNNs). PNNs are an emerging and promising target for preventing drug-induced neuroplasticity because their removal profoundly alters neuroplasticity by cocaine. My recent studies have found and defined a discrete region of the dorsal and intermediate zones of the anterior LHA (LHAad/i) with remarkably robust expression of PNNs around GABAergic neurons that I have discovered to be critical for cocaine- but not sucrose-induced behaviors. The LHAad/i receives input from the prelimbic prefrontal cortex (PL PFC) and sends projections to the VTA. PL PFC and the VTA are major components of the mesocorticolimbic circuitry of motivated behavior and intimately involved in relapse of drug seeking. The role of the LHAad/i within this circuitry has not been studied but is importantly involved in cocaine-seeking behavior. Notably, it is not a part of the more heavily studied regions of the lateral hypothalamic area. I have established that these PNNs are critical for the acquisition of cocaine- but not sucrose-induced behaviors and for cue-induced reinstatement of cocaine seeking. Here I propose to test three hypotheses in three Specific aims that focus on the mechanism and circuitry underlying the prevention of cocaine-induced behavior by LHAad/i PNN removal. Specific Aim 1 (K99 period) will test the hypothesis that LHAad/i PNN removal will increase presynaptic GABA input on VTA DA neurons. I will be formally trained in ex vivo electrophysiology and optically stimulate LHAad/i terminals within the VTA to define the impact of LHAad/i PNN removal on synaptic transmission of VTA neurons. I will begin Specific Aim 2 during the last part of the K99 phase. Specific Aim 2 (K99 and R00 period) will test the hypothesis that chemogenetic activation of LHAad/i neurons that project to the VTA will block cue-induced reinstatement of cocaine seeking. I will continue my training in the use of advanced viral vectors to chemogenetically activate LHAad/i neurons that project to the VTA. Specific Aim 3 (R00 period) will test the hypothesis that LHAad/i PNN removal will reduce PL PFC glutamate input onto LHAad/i neurons. PL PFC projections to the LHAad/i will be optogenetically stimulated. This Aim will be conducted independently during years 4 and 5 of the R00 period to apply the training I received during the K99 period. Central to successful long-term relapse prevention is the need to modify new targets that underlie cocaine-induced plasticity within the circuitry of motivated behavior. The proposed training is fundamental for the PI’s successful transition from postdoctoral fellow to an independent tenure-track faculty position.