The Role of Fyn Kinase in the Dorsal Striatum in Heroin Use Disorder

项目摘要/摘要： 阿片类药物使用障碍是美国的一种公共健康危机，大约有8万人过量使用阿片类药物 2021年。上瘾可以概念化为三个阶段：沉迷/沉迷，戒断/消极情绪，以及 全神贯注/渴望。目前阿片类药物使用障碍的治疗方法是替代奖励和预防戒断， 但与第三阶段成瘾相关的习惯性/强迫性使用存在治疗缺口， 这就需要更好地理解这种行为的分子和细胞基础。使用 海洛因吸毒者死后背侧纹状体标本表观基因组的无偏筛选 赫德实验室发现编码Fyn激酶基因的启动子区域是变异最大的区域 这可以用神经元中海洛因的使用来解释。在这些人类样本中，Fyn mRNA的表达均升高 海洛因自我给药大鼠的背侧纹状体。对Fyn的抑制要么是用一个小的 分子药物或siRNA注射到背侧纹状体降低了对海洛因的反应 旧病复发的模式。背侧纹状体的不同亚区调节药物寻找的不同方面 行为。我发现，强迫性寻求海洛因的大鼠在两种情况下都表现出Fyn表达增加 背内侧和背外侧纹状体，而非强迫服用海洛因的大鼠显示FYN增加 在背内侧亚区表达。我的项目将研究细胞和分子机制。 芬恩有海洛因自我给药行为。我会击倒背内侧和背外侧纹状体的Fyn 亚区和测试动机和强迫寻求海洛因的行为，假设Fyn 在背内侧纹状体击倒会减少目标定向反应，而在背外侧击倒FYN会减少目标定向反应 纹状体会降低习惯性反应。我将对这些亚区进行RNA测序，以评估 由Fyn调制的分子网络。为了确定Fyn如何调节海洛因寻找过程中的神经活动，我 将使用体内纤维光度法记录背侧纹状体的神经元活动。这些实验将使 我要揭开Fyn在海洛因使用障碍中作用的分子和细胞机制 动机吸毒与习惯性吸毒对行为模式的影响。我将学习一种行为模式 强迫症、钙成像和RNA测序，这将使我有能力回答与 神经活动的分子变化到我未来作为内科科学家的职业生涯中的行为。

Project Summary/Abstract: Opioid use disorder is a public health crisis in the United States with roughly 80,000 overdoses taking place in 2021. Addiction can be conceptualized in three phases: binge/intoxication, withdrawal/negative affect, and preoccupation/craving. Current treatments for opioid use disorder substitute reward and prevent withdrawal, but there exists a treatment gap for the habitual/compulsive use associated with the third phase of addiction, necessitating better understanding of the molecular and cellular underpinnings of this behavior. Using an unbiased screening of the epigenome of postmortem samples of dorsal striatum from human heroin users, the Hurd Lab identified a promoter region for the gene encoding Fyn kinase as the locus with the most variance explained by heroin use in neurons. Fyn mRNA expression was elevated both in these human samples and in the dorsal striatum of rats that underwent heroin self-administration. Inhibition of Fyn either with a small molecule drug or siRNA infusions into the dorsal striatum decreased response for heroin in a translational model of relapse. Different subregions of the dorsal striatum mediate different aspects of drug-seeking behavior. I found that rats that compulsively sought heroin showed increased Fyn expression in both dorsomedial and dorsolateral striatum, while rats that took heroin non-compulsively showed increased Fyn expression in the dorsomedial subregion. My project will investigate the molecular and cellular mechanisms of Fyn in heroin self-administration behavior. I will knock down Fyn in dorsomedial and dorsolateral striatal subregions and test motivated and compulsive heroin seeking behavior, with the hypothesis that Fyn knockdown in dorsomedial striatum will reduce goal-directed responding, while Fyn knockdown in dorsolateral striatum will reduce habitual responding. I will perform RNA-sequencing in these subregions to assess molecular networks modulated by Fyn. To determine how Fyn regulates neural activity during heroin seeking, I will record neuronal activity in the dorsal striatum using in-vivo fiber-photometry. These experiments will enable me to uncover the molecular and cellular mechanisms underlying Fyn’s role in heroin use disorder and its effects on behavioral models of motivated versus habitual drug taking. I will learn a behavioral model of compulsivity, calcium imaging, and RNA-sequencing which will equip me to answer questions relating molecular changes to neuronal activity to behavior in my future career as a physician-scientist.