DISSECTING DYNORPHIN-KAPPA OPIOID MEDIATED REINSTATEMENT OF NICOTINE PREFERENCE

人中κ阿片受体（KOR）的激活引起烦躁不安，以及激动剂或 啮齿类动物中应激诱导强啡肽释放产生药物寻求的恢复。尽管最近努力 尼古丁的使用是有史以来最高的，每年造成数百万人死亡， 最难戒掉的药物强啡肽/KOR系统活性的不良影响与 增加的药物自我给药，并且已知该系统会导致药物寻求（海洛因， 可卡因、酒精）。虽然存在许多关于药物寻求的KOR依赖性调节的报告，但仍然存在一些问题。 少数研究探讨了应激诱导的强啡肽-KOR活性对尼古丁的作用和机制 复职在我们之前的R 01赠款周期中，我们试图确定压力引起的恢复是否 尼古丁偏好是通过强啡肽和KOR介导的，并绘制了关键的大脑区域， 尼古丁偏好和KOR和强啡肽介导的尼古丁恢复发生。我们确定 杏仁核、海马CA 1区和延髓核神经元参与尼古丁位置偏爱 和复职我们还建立了小鼠尼古丁自我给药的恢复模型， 依赖大韩民国。然而，负责KOR依赖性尼古丁恢复的神经网络，动力学和电路机制尚不清楚。了解强啡肽能神经回路和 KOR导致尼古丁复吸提供了有价值和重要的见解和新的治疗方法 治疗和预防与压力相关的尼古丁复发。上一个周期的证据表明 提示杏仁核（BLA）和延伸杏仁核（BNST）回路是介导脑电活动的关键位点。 KOR对恢复的影响。然而，虽然我们分离出了这个重要的区域，但特定的细胞类型， 回路动力学、可塑性和尼古丁恢复中回路的时间作用尚不清楚。在这个周期中 我们建议系统地剖析KOR的激活，无论是通过应激诱导的强啡肽释放， 强啡肽释放的光遗传学/化学遗传学调节，或选择性KOR的全身给药 激动剂，导致兴奋性BLA至BNST回路中尼古丁位置偏好的恢复。我们提出 使用一系列方法的以下目的：1）确定强啡肽/KOR活性在BLA中的作用， BNST回路作为应激诱导尼古丁偏好恢复的必要和充分条件 逆行病毒拯救（“功能获得”）、体内药理学和条件性小鼠遗传学; 2）用途 光遗传学和体内钙成像，以确定强啡肽和KOR+ BLA到BNST回路是如何 由压力激活，并且在恢复期间; 3）使用尼古丁自我给药（IVSA）的小鼠模型， 确定BLA-BNST回路中的KOR/强啡肽是否是应激诱导的尼古丁恢复所必需的 IVSA。这些研究验证了我们的中心假设，即压力诱导的尼古丁寻求恢复是 通过离散的BLA和BNST细胞、受体和回路内的动态强啡肽-KOR活化介导。

Activation of kappa opioid receptors (KOR) in humans elicits dysphoria, and KOR activation by agonists or by stress-induced dynorphin release in rodents produces reinstatement of drug seeking. Despite recent efforts to curb use, nicotine use is at an all time high, is responsible for millions of deaths each year and remains one of the most difficult drugs to stop using. The aversive effects of dynorphin/KOR system activity have been linked to increased drug self-administration, and this system is known to cause reinstatement of drug seeking (heroin, cocaine, alcohol). While many reports of KOR dependent regulation of drug-seeking exist, there are are still few studies examining the role and mechanisms of stress-induced dynorphin-KOR activity on nicotine reinstatement. In our prior R01 grant cycle we sought to determine whether stress-induced reinstatement of nicotine preference is mediated through dynorphin and KOR, and mapped the critical brain regions where nicotine preference, and KOR and dynorphin mediated nicotine reinstatement occur. We determined that the amgydala, CA1 of hippocampus, and nucleus accumbens neurons are involved in nicotine place preference and reinstatement. We also established a reinstatement model of nicotine self-administration in mice that is KOR dependent. However, the neural networks, dynamics and circuit mechanisms responsible for KOR-dependent nicotine reinstatement are not understood. Understanding how dynorphinergic neural circuits and KOR cause nicotine reinstatement provides valuable and important insights and new therapeutic approaches to the treatment and prevention of stress-related nicotine relapse. Evidence from our prior cycle strongly suggests that amygdalar (BLA) and extended amgydala (BNST) circuits are the critical loci mediating the effects of KOR on reinstatement. However, while we isolated this region as important, the specific cell types, circuit dynamics, plasticity, and the temporal role of circuit in nicotine reinstatement is not known. In this cycle we propose to methodically dissect how activation of KOR, either by stress-induced dynorphin release, optogenetic/chemogenetic modulation of dynorphin release, or systemic administration of a selective KOR agonist, results in reinstatement of nicotine place preference in an excitatory BLA to BNST circuit. We propose the following Aims using an array of approaches: 1) determine the role of dynorphin/KOR activity in a BLA to BNST circuit as necessary and sufficient for stress-induced reinstatement of nicotine preference using retrograde viral rescue (“gain of function”), in vivo pharmacology, and conditional mouse genetics; 2) Use optogenetics and in vivo calcium imaging to determine the how dynorphin and KOR+ BLA to BNST circuits are activated by stress, and during reinstatement; 3) Using a mouse model of nicotine self-administration (IVSA), determine if KOR/Dynorphin in the BLA-BNST circuit is required for stress-induced reinstatement of nicotine IVSA. These studies test our central hypothesis that stress-induced reinstatement of nicotine seeking is mediated via dynamic dynorphin-KOR activation within discrete BLA and BNST cells, receptors, and circuits.