5HT2c-CRF interactions in the BNST: Relevance to anxiety and alcohol

BNST 中的 5HT2c-CRF 相互作用：与焦虑和酒精的相关性

基本信息

批准号：
8738264
负责人：
Catherine Anne Marcinkiewcz
金额：
$ 5.51万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-09-01 至 2015-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8738264
关键词：
Agonist Agreement Alcohol abuse Alcohol dependence Alcohol withdrawal syndrome Alcohols Anxiety Behavior Behavioral Brain region Chronic Clinical Corticotropin-Releasing Hormone Data Disease Electrophysiology (science)Emotional Ethanol Ethanol dependence Goals Immunoblotting Individual Infusion procedures Investigation Knockout Mice Mediating Membrane Potentials Messenger RNA Molecular Mus National Institute on Alcohol Abuse and Alcoholism Neurons Pharmaceutical Preparations Play Public Health Rattus Receptor Activation Receptor Signaling Regulation Relapse Reporter Research Role Serotonin Signal Pathway Signal Transduction Site Slice Social Interaction Structure of terminal stria nuclei of preoptic region System Techniques Test Result Testing Therapeutic Intervention Tracer United States Substance Abuse and Mental Health Services Administration Ventral Tegmental Area Wild Type Mouse Withdrawal Work alcohol exposure base craving density design drug of abuse effective therapy immunoreactivity neural circuit neurochemistry neuronal excitability problem drinker public health relevance receptor relating to nervous system research study social

项目摘要

DESCRIPTION (provided by applicant): Alcohol abuse is a significant public health burden that is often difficult to manage with current treatment options (NIAAA 1994). Chronic ethanol can induce adaptations in neural circuits that govern emotional behavior and anxiety and may have relevance for ethanol dependence. Serotonin 2c (5HT2c) and corticotrophin-releasing factor (CRF) systems are both dysregulated by chronic ethanol and contribute to the anxiety-inducing effects of ethanol withdrawal (Koob 2001; Overstreet 2003; Knapp 2004; Overstreet 2006; Heilig 2007). The goal of this application is to unravel the molecular basis for 5HT-CRF interactions in the bed nucleus of stria terminalis (BNST), a brain region that was previously shown to be an important neural substrate of anxiety and relapse (Erb 1999). Our central hypothesis is that chronic intermittent ethanol (CIE) increases 5HT2c receptor (5HT2c-R) signaling in the BNST, which in turn activates CRF neurons, causing an increase in anxiety-like behavior that is observed during ethanol withdrawal. Specific Aim 1 is designed to investigate the impact of 5HT2c-R signaling on excitability of CRF neurons in the BNST using ex vivo slice electrophysiology in a recently developed CRF-Ai3 reporter mouse. [Given the potential confounds associated with CRF reporter mice, we include a converging approach that targets the dense CRF projection from the BNST to VTA. Using retrograde tracer beads injected into the VTA of wild-type mice, we will record from putative CRF neurons in the BNST that project to the VTA.] The effects of 5HT2c-R agonists and antagonists on membrane potential and current induced spiking will be examined to determine if 5HT2c-R activation depolarizes CRF neurons in the BNST using both approaches. We will also investigate downstream signaling pathways (e.g. Gq/11/PLC) that may underlie 5HT2c-R effects in CRF neurons. Together, these experiments will clarify the functional interactions between 5HT and CRF systems in the BNST. Specific Aim 2 examines the effects of CIE on 5HT2c-R signaling in the BNST. Using ex vivo slice electrophysiology in CRF-Ai3 reporter [and VTA tracer-injected wild-type mice], we will examine the effects of CIE on excitability and 5HT2c signaling in CRF neurons. Together, these experiments will provide converging results indicating whether CIE leads to functional adaptations in 5HT2c-R systems in the BNST. Specific Aim 3 is designed to clarify the role of 5HT2c-R signaling in the BNST in anxiety-like behavior following CIE. Preliminary data indicates that CIE induces anxiety-like behavior in mice in the social approach test. Given the putative actions of 5HT2c-Rs on CRF neurons in the BNST, we predict that 5HT2c-R antagonists infused into the BNST will alleviate anxiety associated with ethanol withdrawal. The results of this study will indicate whether 5HT2c-R systems in the BNST are a potential target for the treatment of anxiety during ethanol withdrawal. In total, the proposed research will provide essential information concerning 5HT2c- CRF interactions in the BNST and the role that these systems play in alcohol-induced anxiety.

描述（由申请人提供）：酗酒是一个重大的公共健康负担，通常很难用当前的治疗方案来控制（NIAAA 1994）。长期摄入乙醇会引起控制情绪行为和焦虑的神经回路的适应，并可能与乙醇依赖有关。血清素 2c (5HT2c) 和促肾上腺皮质激素释放因子 (CRF) 系统都会因长期乙醇而失调，并导致乙醇戒断引起的焦虑诱发效应 (Koob 2001; Overstreet 2003; Knapp 2004; Overstreet 2006; Heilig 2007)。该应用的目标是揭示终纹床核 (BNST) 中 5HT-CRF 相互作用的分子基础，该大脑区域先前被证明是焦虑和复发的重要神经基质 (Erb 1999)。我们的中心假设是，慢性间歇性乙醇 (CIE) 会增加 BNST 中的 5HT2c 受体 (5HT2c-R) 信号传导，进而激活 CRF 神经元，导致乙醇戒断期间观察到的焦虑样行为增加。具体目标 1 旨在利用最近开发的 CRF-Ai3 报告小鼠的离体切片电生理学研究 5HT2c-R 信号传导对 BNST 中 CRF 神经元兴奋性的影响。 [考虑到与 CRF 报告小鼠相关的潜在混淆，我们采用了一种针对从 BNST 到 VTA 的密集 CRF 投影的收敛方法。使用逆行示踪珠注射到野生型小鼠的 VTA 中，我们将记录 BNST 中推定的 CRF 神经元投射到 VTA 的情况。] 将检查 5HT2c-R 激动剂和拮抗剂对膜电位和电流诱导的尖峰的影响使用这两种方法确定 5HT2c-R 激活是否使 BNST 中的 CRF 神经元去极化。我们还将研究可能是 CRF 神经元中 5HT2c-R 效应的下游信号通路（例如 Gq/11/PLC）。这些实验将共同阐明 BNST 中 5HT 和 CRF 系统之间的功能相互作用。具体目标 2 检查 CIE 对 BNST 中 5HT2c-R 信号传导的影响。在 CRF-Ai3 报告基因 [和注射 VTA 示踪剂的野生型小鼠] 中使用离体切片电生理学，我们将检查 CIE 对 CRF 神经元兴奋性和 5HT2c 信号传导的影响。总之，这些实验将提供收敛结果，表明 CIE 是否会导致 BNST 中 5HT2c-R 系统的功能适应。具体目标 3 旨在阐明 BNST 中 5HT2c-R 信号传导在 CIE 后焦虑样行为中的作用。初步数据表明，CIE 在社交方法测试中会诱发小鼠的焦虑样行为。鉴于 5HT2c-R 对 BNST 中 CRF 神经元的假定作用，我们预测注入 BNST 的 5HT2c-R 拮抗剂将减轻与乙醇戒断相关的焦虑。这项研究的结果将表明 BNST 中的 5HT2c-R 系统是否是治疗乙醇戒断期间焦虑的潜在靶点。总的来说，拟议的研究将提供有关 BNST 中 5HT2c-CRF 相互作用以及这些系统在酒精引起的焦虑中所起的作用的重要信息。