Role of lateral habenula in methamphetamine TAAR1-mediated synaptic plasticity and aversion

项目摘要 相当多的研究集中在药物使用障碍作为动机障碍，涉及内在或药物- 诱导奖赏途径功能。然而，本申请的焦点在于对抗以下的令人厌恶的效果： 甲基苯丙胺（MA），可能会遏制其使用，这是很少研究。理查兹一家（菲利普斯） 一个实验室确定了微量胺相关受体1（TAAR 1）作为影响MA诱导的 厌恶TAAR1是一种位于细胞内的G蛋白偶联受体。MA只有在以下情况下才能访问TAAR 1： 被输送到细胞中。这通过细胞外膜转运蛋白发生，如多巴胺和多巴胺受体。 5-羟色胺转运蛋白，分别为DAT和SERT。我们认为MA激活多巴胺中的TAAR 1， 和5-羟色胺神经元负责MA诱导的厌恶和单胺能电路的相互作用， 外侧缰（LHb）是特别重要的。本报告中提出的研究的总体目标 应用是了解单胺能神经元LHb的相互作用，负责MA的经验， 通过TAAR 1诱导厌恶，可能降低MA使用的风险。我们的初步数据显示MA激活了 外侧缰核（LHb）神经元，特别是在具有功能性TAAR 1的小鼠中。目标1中的研究将使用切片 电生理学以检查MA在腹侧被盖区多巴胺和多巴胺中的TAAR 1依赖性作用。 背中缝5-羟色胺神经元，比较野生型和CRISPRed基因敲入小鼠的切片， 功能性与非功能性TAAR1。Aim 1研究还将使用光遗传学刺激， 检查MA对来自LHb的突触能突触的影响。根据我们发表的研究结果， 功能行为学研究将探讨谷氨酸受体亚单位GluN2B在MA中的作用 厌恶和摄入。目标2将进行行为研究，重点是LHb，这已被证明是 介导其他类型的厌恶，尚未研究MA厌恶。我们将在小鼠中消融LHb， 和无功能性TAAR 1的情况下，并研究对MA厌恶和摄入的影响。最后，Aim 3研究将使用 一种逆行示踪剂，用于识别投射到腹侧被盖或中缝背侧的LHb神经元。 电生理学研究将确定多巴胺或5-羟色胺是否调节LHb的MA激活 神经元和确定是否MA激活TAAR 1在腹侧被盖区的突触前终末 多巴胺神经元或中缝背核5-羟色胺神经元调节MA的作用， 没有功能性TAAR1。因此，该建议利用遗传工具，通过电生理学进行电路分析， 和行为分析，以确定MA如何以TAAR1依赖的方式参与LHb神经元， LHb回路对于MA诱导的厌恶行为是必要的，以及它们是否抑制MA摄入。这 该策略可用于研究MA对其他区域中TAAR 1信号传导的影响。机制研究 对MA诱导的厌恶的潜在敏感性可能导致鉴定一类新的治疗剂。

PROJECT SUMMARY Considerable research has focused on drug use disorders as motivational disorders involving inherent or drug- induced reward pathway function. However, the focus of this application is on opposing aversive effects of methamphetamine (MA) that may curb its use, which have been little studied. The Richards (Phillips) laboratory identified the trace amine associated receptor 1 (TAAR1) as a critical target impacting MA-induced aversion. TAAR1 is an intracellularly located G protein-coupled receptor. MA gains access to TAAR1 only if it is transported into the cell. This occurs via extracellular membrane transporters, such as dopamine and serotonin transporters, DAT and SERT, respectively. We propose that TAAR1 activation by MA in dopamine and serotonin neurons is responsible for MA-induced aversion and that monoaminergic circuit interactions with the lateral habenula (LHb) are of particular importance. The overarching goal of the studies proposed in this application is to understand the monoaminergic neuron-LHb interactions responsible for the experience of MA- induced aversion via TAAR1 that may reduce risk for MA use. Our preliminary data show that MA activates lateral habenula (LHb) neurons, specifically in mice with functional TAAR1. The studies in Aim 1 will use slice electrophysiology to examine the TAAR1-dependent effects of MA in ventral tegmental area dopamine and dorsal raphe serotonin neurons, comparing slices from wildtype and CRISPRed knock-in mice, mice that have functional vs. nonfunctional TAAR1, respectively. Aim 1 studies will also use optogenetic stimulation to examine the effects of MA on glutamatergic synapses from the LHb. Based on our published findings, functional behavioral studies in this aim will examine the role of a glutamate receptor subunit, GluN2B, on MA aversion and intake. Aim 2 will perform behavioral studies focused on the LHb, which has been shown to mediate other types of aversion, has not been studied for MA aversion. We will ablate the LHb in mice with and without functional TAAR1 and study the impact on MA aversion and intake. Finally, Aim 3 studies will use a retrograde tracer to identify the LHb neurons that project to either the ventral tegmentum or dorsal raphe. Electrophysiological studies will determine whether dopamine or serotonin modulate MA activation of LHb neurons and determine whether MA activation of TAAR1 in presynaptic terminals of ventral tegmental area dopamine neurons or dorsal raphe serotonin neurons regulate the effects of MA using slices from mice with and without functional TAAR1. Thus, this proposal utilizes genetic tools, circuit analysis via electrophysiology and behavioral analysis to identify how MA engages LHb neurons in a TAAR1-dependent manner, whether LHb circuits are necessary for MA-induced aversion behaviors, and whether they inhibit MA intake. This strategy could be used to study effects of MA on TAAR1 signaling in other regions. The study of mechanisms underlying sensitivity to MA-induced aversion could lead to the identification of a new class of therapeutics.