Brain endorphin targets of low dose alcohol

低剂量酒精的大脑内啡肽目标

基本信息

批准号：
9762559
负责人：
M. FOSTER OLIVE
金额：
$ 36.31万
依托单位：
ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-09-19 至 2021-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9762559
关键词：
Acute Affinity Alcohol abuse Alcohol consumption Alcohols Attenuated Biological Blood Brain Consumption Data Dependence Development Dose Endorphins Ethanol Female Gated Ion Channel Genes Genetic Transcription Goals Hypothalamic structure Impaired cognition Intoxication Ion Channel Gating Legal Ligands Medical Methods Molecular Molecular Target Motivation Mouse Protein Mus Nature Neurons Nucleus Accumbens Peptides Pharmacology Pro-Opiomelanocortin Procedures Proteins Rattus Rewards RiboTag Self Administration Societies Specificity Structure of nucleus infundibularis hypothalami System Testing Transgenic Mice Viral alcohol effect cell type cost desensitization drinking drug of abuse endogenous opioids enhanced green fluorescent protein experimental study extracellular male neural circuit neurochemistry novel promoter protein function public health relevance socioeconomics translational impact transmission process voltage

项目摘要

ABSTRACT The precise molecular targets of ethanol action in the brain have remained elusive for decades, primarily as a result of the transient and low-affinity nature of ethanol interactions with specific proteins or other cellular components. The endogenous opioid system has been implicated in the rewarding, reinforcing, motivational, and neurochemical effects of drugs of abuse, including ethanol. We have previously demonstrated that acute ethanol administration in rats significantly increases extracellular endorphin levels in the nucleus accumbens (NAc). We have also generated novel preliminary data indicating that immunoneutralization of -endorphin in the NAc shell subregion, but not the core, attenuates low dose ethanol self-administration. These findings suggest that endorphinergic transmission in the NAc shell contributes to the motivational effects of low dose ethanol. Finally, we utilized transgenic mice that express enhanced green fluorescent protein (EGFP) under the control of the promoter for the -endorphin precursor peptide pro-opiomelanocortin (POMC), to assess the potential activation of these neurons by low dose ethanol. We observed that in these POMC-EGFP mice, low dose ethanol consumption in the drinking-in-the-dark paradigm resulted in brain and blood ethanol levels <10 mM, and activated POMC-expressing neurons in the arcuate nucleus of the hypothalamus (ArcN). Collectively, these data indicate that brain POMC/endorphin systems are molecular targets of low dose ethanol. However, additional studies are needed to test our overarching hypothesis that ArcN POMC-expressing neurons are a target of low dose ethanol in the brain. To accomplish this, we have formulated the following inter-related yet independent Specific Aims. In Aim 1, we will further characterize the ability of low dose ethanol to activate ArcN POMC-expressing neurons. POMC-EGFP mice will be tested in the drinking-in-dark paradigm to determine the dose-dependency, specificity, and desensitization of ethanol-induced activation of ArcN POMC-expressing neurons. In Aim 2, we will determine the accumbal targets of ArcN POMC-expressing neurons activated by low dose ethanol. This will be accomplished by the use of Cre-dependent viral retrograde tracing methods in POMC- Cre mice. Finally, in Aim 3, we will determine the molecular adaptations in ArcN POMC-expressing neurons that occur following low dose ethanol consumption. This will be accomplished by utilizing POMC-Cre Ribotag mice to determine cell-type specific changes in RNA expression of biologically related genes induced by low dose ethanol consumption. To increase the translational impact of these studies, all proposed experiments will utilize both male and female subjects, and ethanol intake procedures that allow voluntary consumption as opposed to passive administration by an experimenter. Together, these studies will ultimately guide the development of pharmacological or other approaches for inactivating the effects of ethanol in the brain, which may ultimately reduce the medical, socioeconomic and legal costs of ethanol abuse to society.

抽象的数十年乙醇相互作用与特定蛋白或其他细胞的瞬时和低亲和力性质的结果成分。内源性阿片类药物系统已在奖励，增强，激励性，以及包括乙醇在内的滥用药物的神经化学作用。我们以前已经证明了急性大鼠的乙醇给药可显着增加伏隔核的细胞外内吗啡水平（NAC）。我们还产生了新的初步数据，表明-内啡肽在 NAC壳子区域（但不是核心）减弱了低剂量的乙醇自我给药。这些发现表明NAC壳中的内啡肽传播有助于低剂量的动机作用乙醇。最后，我们利用了表达增强绿色荧光蛋白（EGFP）的转基因小鼠控制the的启动子的-内啡肽前体辣椒蛋白皮质素（POMC），以评估低剂量乙醇对这些神经元的潜在激活。我们观察到在这些POMC-EGFP小鼠中，低在黑暗范围范围内饮酒中的剂量乙醇消耗导致大脑和血液乙醇水平<10 MM和下丘脑（ARCN）的弧形核中激活了POMC的神经元。共同这些数据表明脑POMC/内啡肽系统是低剂量乙醇的分子靶标。然而，还需要进行其他研究来检验我们的总体假设，即表达ARCN POMC的神经元是一个大脑中低剂量乙醇的靶标。为此，我们已经制定了以下相互关联的在AIM 1中，我们将进一步表征低剂量乙醇激活ARCN的能力表达POMC的神经元。 POMC-EGFP小鼠将在黑暗中的范式中进行测试，以确定乙醇诱导的ARCN POMC表达激活的剂量依赖性，特异性和脱敏神经元。在AIM 2中，我们将确定由低的ARCN表达ARCN表达神经元的授权靶标剂量乙醇。这将通过在POMC-中使用CRE依赖性病毒逆行追踪方法来实现 CRE小鼠。最后，在AIM 3中，我们将确定表达ARCN POMC的神经元中的分子适应发生低剂量的乙醇消耗。这将通过使用pomc-cre ribotag小鼠来实现确定低剂量诱导的生物学相关基因的RNA表达的细胞类型特异性变化乙醇消耗。为了增加这些研究的翻译影响，所有提出的实验都将利用男性和女性受试者以及允许自愿消费而不是专家的被动管理。这些研究共同指导药理学或其他方法使乙醇在大脑中的作用失活，这可能最终可能减少乙醇滥用社会的医学，社会经济和法律成本。