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：美国的阿片类药物使用障碍和阿片类药物过量死亡率达到了前所未有的 19009年大流行期间的水平。了解内源性阿片类活动如何影响自然奖励寻求对于理解阿片类药物使用障碍的神经药物基础至关重要。先前的研究暗示了中唇的多巴胺途径，该途径是指从腹侧突出的多巴胺神经元奖励和成瘾中的伏隔核（NAC）的对接区域（VTA）。最近的研究表明 VTA中含有神经元（Vtagaba）的γ-氨基丁酸（GABA）提供了多巴胺的局部抑制突触到NAC的神经元，从而在控制奖励行为中发挥作用。重要的是，这些 Vtagaba神经元包含多种G蛋白偶联受体，特别是阿片受体（MOR）。但是，这些受体的确切作用及其在Vtagaba神经元中的信号发挥，因此自然奖励的调节尚不清楚。内源性阿片类神经肽的来源这些影响如何尚未描述信号传导和活动。该提议的核心假设是 Vtagaba神经元上的µ-阿片受体信号传导受传入的内源性阿片类药物的调节，由此产生 vtagaba神经元令人兴奋。这导致控制多巴胺神经元的活性，并最终控制自然奖励的表达。该提案直接解决了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，神经药物和电路变化。目的 1将分离内源性µ阿片类药物在VTA中的作用在多巴胺信号传导和自然奖励中的作用 - 寻求。 AIM1A使用离体两光子成像和神经药理学方法可视化Vtagaba和 VTA DA动力学。 AIM1B将研究MOR消融在VTA中对多巴胺活性和行为。 AIM 2将在自然奖励期间隔离VTA中内源性µ-阿片类药物的来源和动力学行为。在AIM 2A中，我将使用病毒追踪技术来解剖可视化后来的输入下丘脑（LH）到VTA。 AIM 2B将测试内源性μ阿片信号传导对Vtagaba和在寻求奖励行为期间，NAC中的DA活动。在AIM 2C中，我将使用分子方法 CRISPR基因编辑和最近开发的µ-阿片类生物传感器（µMASS1）以了解时空在寻求奖励期间，Vtagaba神经元中MOR信号的各个方面。这种职业发展培训和一系列实验将洞悉内源性MOR信号在多巴胺能活性中的作用和自然的回报。对于此建议，我将训练切片电生理学，两光子切片成像，基因编辑，分子神经药理学和行为方法，以了解特定神经肽调节奖励电路。该F31提案将大大推动我的职业发展计划和为我做好一名独立的学术神经药学家的职业。