Isolating the role of endogenous mu-opioid activity in the VTA during natural reward

分离自然奖赏期间 VTA 中内源性 mu-阿片活性的作用

基本信息

批准号：
10749349
负责人：
Catalina Alejandra Zamorano
金额：
$ 4.77万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-07-01 至 2026-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10749349
关键词：
Ablation Address Affect Agonist Anatomy Area Behavior Behavioral Biosensor Brain COVID-19 pandemic Clustered Regularly Interspaced Short Palindromic Repeats Color Complex Consumption Death Rate Development Plans Disinhibition Dopamine Drug usage Electrophysiology (science)Excision Fiber G-Protein-Coupled Receptors Genes Goals Hypothalamic structure Image Individual Lateral Learning Ligands Measures Mentors Methods Modeling Modernization Molecular Mouse Strains National Institute of Drug Abuse Neurobiology Neurons Neuropeptides Neuropharmacology Nucleus Accumbens Opioid Opioid Peptide Opioid Receptor Pathway interactions Phase Photometry Play Property Prosencephalon Receptor Activation Receptor Signaling Regulation Reporting Research Resolution Rewards Role Series Severities Shapes Signal Transduction Slice Source Substance Use Disorder Synapses System Techniques Testing Training United States Ventral Tegmental Area Viral Visualization abuse liability addiction calcium indicator career career development chronic pain relief conditional knockout dopaminergic neuron endogenous opioids experience experimental study gamma-Aminobutyric Acid in vivo insight mu opioid receptors neuronal excitability opioid epidemic opioid mortality opioid overdose opioid use disorder pain reduction receptor response skill acquisition spatiotemporal training opportunity two-photon

项目摘要

SUMMARY: Opioid use disorder and opioid overdose death rates in the United States reached unprecedented levels during the COVID-19 pandemic. Understanding how endogenous opioid activity affects natural reward seeking is crucial to understanding the neuropharmacological basis of opioid use disorder. Previous research implicates the mesolimbic dopamine pathway, which refers to dopamine neurons projecting from the Ventral Tegmental Area (VTA) to the Nucleus Accumbens (NAc), in reward and addiction. Recent studies show that gamma-aminobutyric acid (GABA) containing neurons in the VTA (VTAGABA) provide local inhibition of dopamine neurons that synapse onto the NAc, thus playing a role in regulating reward behaviors. Importantly, these VTAGABA neurons contain a variety of G-protein coupled receptors, specifically the µ-opioid receptor (MOR). However, the exact role of these receptors and their signaling play in VTAGABA neurons and consequent regulation of natural reward is unknown. The source of endogenous opioid neuropeptide onto these MORs, and how these impacts signaling and activity has not been described. The central hypothesis of this proposal is that µ-opioid receptor signaling on VTAGABA neurons is regulated by afferent endogenous opioid peptides, resulting in disinhibition of VTAGABA neuron excitability. This results in control of dopamine neuron activity, and ultimately the expression of natural reward-seeking. This proposal directly addresses NIDA's Priority Scientific Area 1 that aims to further understand the molecular, neuropharmacological and circuit changes induced by drug use. Aim 1 will isolate the role of endogenous µ-opioid peptides in the VTA on dopamine signaling and natural reward- seeking. Aim1A uses ex vivo two-photon imaging and neuropharmacology approaches to visualize VTAGABA and VTA DA dynamics. Aim1B will investigate the effects of MOR ablation in the VTA on dopamine activity and behavior. Aim 2 will isolate the source and dynamics of endogenous µ-opioids in the VTA during natural reward behavior. In Aim 2A, I will use viral tracing techniques to anatomically visualize inputs from the lateral hypothalamus (LH) to the VTA. Aim 2B will test the effects of endogenous µ-opioid signaling on VTAGABA and DA activity in the NAc during reward seeking behaviors. In Aim 2C, I will use molecular approaches including CRISPR gene-editing and a recently developed µ-opioid biosensor (µMASS1) to understand the spatiotemporal aspects of MOR signaling in VTAGABA neurons during reward seeking. This career development training and series of experiments will provide insight into the role of endogenous MOR signaling on dopaminergic activity and natural reward-seeking. For this proposal, I will train in slice electrophysiology, two-photon slice imaging, gene-editing, molecular neuropharmacology, and behavioral approaches to understand how specific neuropeptides regulate reward circuits. This F31 proposal will greatly advance my career development plan and prepare me for a career as an independent, academic neuropharmacologist.

摘要：美国阿片类药物使用障碍和阿片类药物过量死亡率达到前所未有的水平了解 COVID-19 大流行期间内源性阿片类药物活性如何影响自然奖赏。寻求对于理解阿片类药物使用障碍的神经药理学基础至关重要。涉及中脑边缘多巴胺通路，指的是从腹侧投射的多巴胺神经元被盖区 (VTA) 到伏核 (NAc)，在奖励和成瘾中的作用最近的研究表明，含有 VTA (VTAGABA) 中神经元的 γ-氨基丁酸 (GABA) 提供多巴胺的局部抑制突触到 NAc 的神经元，从而在调节奖励行为中发挥作用。 VTAGABA 神经元含有多种 G 蛋白偶联受体，特别是 µ-阿片受体 (MOR)。然而，这些受体及其信号传导在 VTAGABA 神经元中的确切作用以及随之而来的这些 MOR 上的内源性阿片类神经肽的自然奖赏调节的来源尚不清楚，并且尚未描述这些如何影响信号传导和活动。该提案的中心假设是： VTAGABA 神经元上的 µ-阿片受体信号传导受到传入内源性阿片肽的调节，从而产生 VTAGABA 神经元兴奋性的去抑制，最终控制多巴胺神经元的活动。该提案直接涉及 NIDA 的优先科学领域 1：旨在进一步了解药物使用引起的分子、神经药理学和回路变化。 1 将分离 VTA 中内源性 µ-阿片肽对多巴胺信号传导和自然奖励的作用 - Aim1A 使用离体双光子成像和神经药理学方法来可视化 VTAGABA 和 Aim1B 将研究 VTA 中 MOR 消融对多巴胺活性的影响。目标 2 将分离自然奖励期间 VTA 中内源性 µ-阿片类药物的来源和动态。在目标 2A 中，我将使用病毒追踪技术从解剖学角度可视化来自侧面的输入。下丘脑 (LH) 至 VTA 的目标 2B 将测试内源性 µ-阿片类药物信号传导对 VTAGABA 和的影响。在 Aim 2C 中，NAc 中的 DA 活动包括： CRISPR 基因编辑和最近开发的 µ-阿片类生物传感器 (µMASS1) 来了解时空奖励寻求过程中 VTAGABA 神经元 MOR 信号传导的各个方面。系列实验将深入了解内源性 MOR 信号传导对多巴胺能活性的作用对于这个提议，我将接受切片电生理学、双光子切片成像方面的培训，基因编辑、分子神经药理学和行为方法来了解具体的作用神经肽调节奖励回路。这个 F31 提案将极大地推进我的职业发展计划和为我成为一名独立的学术神经药理学家做好准备。