ETHANOL DISCRIMINATION AND G PROTEIN COUPLING IN BRAIN

酒精的区别性刺激特性可能有助于其在人类中的滥用和成瘾潜力。酒精辨别的动物模型已经表明5-羟色胺（5-HT）受体（包括G/I/O-偶联的5-HT/IB/D受体）参与介导酒精的辨别刺激特性。所提出的初步研究的主要假设是，在大鼠中乙醇歧视的收购与5-HT/L受体活性的变化。我们实验室开发了一种技术，通过激动剂刺激的[35 S] GTP γ S放射自显影术在组织切片中测量受体偶联G蛋白活性。该技术允许以高度的解剖分辨率定量G蛋白偶联受体的生化活性。该方法非常适合于研究乙醇歧视对5-HT 1受体偶联G蛋白活性的影响。将解剖放射自显影观察到5-HT 1受体偶联G蛋白活性变化的区域，并使用激动剂刺激的[35 S] GTP γ S结合和膜中的受体结合进行更多定量生化和药理学分析。这种方法结合了行为药理学、神经解剖学和信号转导生物化学，可能阐明5-HT 1受体在乙醇辨别发展中的神经适应作用。这个试点项目直接解决了中心的目标，关于乙醇的歧视性刺激作用的潜在可能的细胞机制。它将提供进口试验数据，以补充中心项目3中进行的研究，并为Grant博士进行的R 01工作提供信息。

The discriminative stimulus properties of alcohol may contribute to its abuse and addiction potential in humans. Animal models of alcohol discrimination have indicated the involvement of serotonin (5-HT) receptors, including the G/i/o-coupled 5-HT/lB/D receptors, in mediating the discriminative stimulus properties of alcohol. The main hypothesis of the proposed pilot study is that the acquisition of ethanol discrimination in rats is associated with changes in 5-HT/l receptor activity. A technique has been developed in our laboratory, whereby receptor-coupled G-protein activity is measured by agonist-stimulated [35S]GTPgammaS autoradiography in tissue sections. This technique allows quantification of the biochemical activity of G-protein-coupled receptors with a high degree of anatomical resolution. This methodology is ideally suited to the study of the effects of the acquisition of ethanol discrimination on 5-HT1 receptor-coupled G-protein activity. Regions where changes in 5-HT1 receptor-coupled G-protein activity are observed autoradiographically will be dissected, and more quantitative biochemical and pharmacological analysis will be performed using both agonist-stimulated [35S]GTPgammaS binding and receptor binding in membranes. This approach, which combines behavioral pharmacology with neuroanatomy and signal transduction biochemistry, may elucidate the neuroadaptive role of 5-HTl receptors in the development of ethanol discrimination. This pilot project directly addresses the Center aims regarding the possible cellular mechanisms underlying ethanol's discriminative stimulus effects. It will provide import pilot data that can supplement the studies performed in Project 3 of the Center, as well as provide information for the R01 work conducted by Dr. Grant.