Nucleus accumbens fast-spiking interneurons regulate opioid reward and addiction

项目摘要 阿片类药物成瘾是一种公共健康危机，其特征是强迫性寻求毒品和 容易复发，几乎没有可用的治疗选择。伏隔核(NAC)是中枢 在奖赏回路内，并在药物和与药物相关的线索的激励价值中发挥关键作用。在 NAC的异质性神经元亚型存在稀疏分布的快脉冲中间神经元(FSIS)。 NAC FSIS接受来自大脑皮层、丘脑和边缘区域的强烈兴奋性输入，并对 对局部投射神经元的抑制，使它们成为翻译治疗的首选 减轻阿片类药物滥用流行负担的战略。此应用程序的总体目标是 阐明NAC FSI电路如何响应和调节阿片类药物的自我给药。 在明尼苏达大学帕特里克·罗斯韦尔博士的主要指导下，勒费夫尔博士 利用分子和行为药理学技术的研究生培训，以及博士后培训 活体电生理学研究非偶发性阿片成瘾模型中NAC回路的适应性。这 独立之路奖将提供机会，以扩大候选人的专业知识，包括 在罗斯韦尔博士的持续指导下，生物纤维光度法、钙成像和化学遗传学。至 扩大成瘾研究的职业发展，Lefevre博士将得到共同导师Dr。 Mark Thomas在雌性和雄性小鼠中实施或有阿片类药物自我给药模型。 在获奖的指导(K99)阶段，将使用纤维光度法钙成像来监测 NAC FSIS在间歇给药(INTA)芬太尼自我给药方案中的活体活动模式 神经群体如何对临时芬太尼和芬太尼相关提示做出反应。随后，一个 化学发生方法，这将涉及专门激活的设计者受体的靶向表达 NAC FSIS的设计药物(DREADD)将被用来检验这些神经元发挥功能的假设 在与成瘾相关的行为中扮演的角色。芬太尼自行给药后，DREADS将用于兴奋或 在递进比率和线索诱导的恢复测试之前抑制NAC FSIS。这一创新的组合 将使用工具来测试NAC、FSIS和芬太尼自我给药表现之间的关系。 该奖项的R00阶段将把Lefevre博士的独立研究与她的导师和 扩大以识别兴奋性突触传入NAC FSIS的作用。将利用体外电生理学 确定芬太尼自身诱导的NAC-FSIS的传入特异性兴奋性突触可塑性适应 行政管理。此外，R00 AIMS将结合电生理学、光遗传学和钙成像 开发恢复阿片类药物引起的FSI回路和成瘾样改变的刺激方案的专业知识 行为。总体而言，本奖项中提出的目标将确定阿片类药物自我给药和 为勒费夫尔博士研究成瘾的神经回路的独立研究项目奠定了基础。

Project Abstract Opioid addiction is a public health crisis, characterized by compulsive drug seeking and a pervasive vulnerability to relapse, with few therapeutic options available. The nucleus accumbens (NAc) is a central hub within reward circuitry and plays a critical role in the motivational value of drugs and drug-associated cues. Within the heterogeneous neuronal subtypes of the NAc exist the sparsely distributed fast-spiking interneurons (FSIs). The NAc FSIs receive strong excitatory inputs from cortical, thalamic and limbic regions and exert powerful inhibition over the local projection neurons, making them a prime candidate for translational therapeutic strategies to reduce the burden of the opioid abuse epidemic. The overall objectives of this application are to elucidate how NAc FSI circuitry responds to, and mediates, opioid self-administration. Under the primary mentorship of Dr. Patrick Rothwell at the University of Minnesota, Dr. Lefevre has utilized graduate training in molecular and behavioral pharmacology techniques, and post-doctoral training in ex- vivo electrophysiology to study adaptations in NAc circuitry in non-contingent opioid addiction models. This Pathway to Independence Award will provide the opportunity to broaden the candidate’s expertise to include in vivo fiber photometry calcium imaging, and chemogenetics, under the continued mentorship of Dr. Rothwell. To expand career development in addiction research, Dr. Lefevre will receive additional support from co-mentor Dr. Mark Thomas in the implementation of contingent opioid self-administration models in female and male mice. During the mentored (K99) phase of the award, fiber photometry calcium imaging will be used to monitor in vivo activity patterns of NAc FSIs in an Intermittent Access (IntA) fentanyl self-administration protocol to identify how this neural population responds to contingent fentanyl and fentanyl-associated cues. Subsequently, a chemogenetic approach, which will involve targeted expression of Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) by NAc FSIs, will be used to test the hypothesis that these neurons play a functional role in addiction-related behavior. Following fentanyl self-administration, DREADDs will be used to excite or inhibit NAc FSIs prior to progressive ratio and cue-induced reinstatement tests. This innovative combination of tools will be used to test the relationship between NAc FSIs and the manifestation of fentanyl self-administration. The R00 phase of the award will distinguish Dr. Lefevre’s independent research from her mentors and broaden to identifying the role of excitatory synaptic inputs to NAc FSIs. Ex-vivo electrophysiology will be utilized to define input-specific excitatory synaptic plasticity adaptations in NAc FSIs induced by fentanyl self- administration. Additionally, the R00 aims will incorporate electrophysiology, optogenetic and calcium imaging expertise to develop stimulation protocols that restore opioid induced shifts in FSI circuitry and addiction-like behavior. Overall, the aims proposed in this award will identify key FSI circuits in opioid self-administration and provide the foundation for Dr. Lefevre’s independent research program studying the neural circuitry of addiction.