ALCOHOL ACTIONS--A BEHAVIORAL PHARMACOGENETICS APPROACH

该研究描述的重点是GABA的作用，苯二氮卓类 受体（GABA/BDZR）氯（Cl-）通道复合物介导急性 酒精和相关麻醉剂的初始镇静作用。 目前还不清楚这种相互作用是否直接发生， 是，在或接近复杂的水平，或间接通过机制 由次级系统介导。该研究还检验了假设 乙醇敏感性的遗传差异是由于，至少部分是， 通道的结构/功能和调制的差异 复杂.因此，有两个一般的具体目标。一是 检查和表征酒精对GABA/BDZR Cl-的影响 通道复合物，重点是苯二氮卓类网站的作用。到 为了达到这一目标，急性酒精暴露对功能的影响 和调节GABA/BDZR在啮齿类动物脑膜囊泡将是 测定乙醇和各种苯并二氮杂卓配体对 确定GABA介导的Cl-电导率的动力学参数 Cl-交换和脱敏）将使用淬火流进行测量 技术. 第二个目的是尝试将体外敏感性 （乙醇增强GABA-Cl反应），具有体内敏感性 （镇静）乙醇。特别令人感兴趣的是评估性质和 乙醇与苯二氮卓类药物遗传相关性的有效性 灵敏度第二个目标的一个组成部分是评估遗传 这种酒精表型的结构（单基因与多基因控制）。到 为了实现这一目标，遗传定义的啮齿动物种群（选择 品系和重组近交系）将被测试的能力， 各种试剂调节GABA/BDZR Cl-通道复合物。的影响 将在脑中评估流量平衡和脱敏率 来自重组近交系小鼠品系的膜。 此外， 脂质微环境、糖基化和各种细胞内组分 乙醇调节通道功能的能力将是 使用溶解和纯化的受体复合物进行检查，所述受体复合物来源于 啮齿类动物选择性繁殖的乙醇敏感性的差异。 是 预计这些研究将提供深入了解神经和 对酒精敏感的遗传机制。这将在 转使我们能够更好地了解某些遗传方式 行为和神经化学反应。此外，这些研究 将扩大我们对GABA/BDZR Cl-的调节和功能的认识， 渠道体系

The research described focuses on the role of the GABA,benzodiazepine receptor (GABA/BDZR) chloride (Cl-) channel complex in mediating the acute initial sedative effects of alcohol and related intoxicant-anesthetics. Currently, it is still unknown if this interaction occurs directly, that is, at or near the level of the complex, or indirectly via mechanisms mediated by secondary systems. The research also examines the hypothesis that genetic differences in ethanol sensitivity are due, at least in part, to differences in the structure/function and modulation of the channel complex. Accordingly, there are two general specific aims. First, to examine and characterize the effects of alcohol on the GABA/BDZR Cl- channel complex, with a focus on the role of the benzodiazepine site. To accomplish this goal, the effect of acute alcohol exposure on the function and regulation of the GABA/BDZR in rodent brain membrane vesicles will be determined. The effects of ethanol and various benzodiazepine ligands on the kinetic parameters that determine GABA-mediated Cl- conductance (rates of Cl- exchange and desensitization) will be measured using quench flow techniques. The second aim is to attempt to link in vitro sensitivity (ethanol augmentation of GABA-Cl- response) with in vivo sensitivity (sedation) to ethanol. Of particular interest is evaluating the nature and validity of the genetic correlation between ethanol and benzodiazepine sensitivity. A component of this second aim is to evaluate the genetic architecture (single- vs polygenic control) of this alcohol phenotype. To accomplish this goal, genetically defined populations of rodents (selected lines and recombinant inbred strains) will be tested for the ability of various agents to modulate the GABA/BDZR Cl- channel complex. The effects on flux equilibrium and rates of desensitization will be assessed in brain membranes from recombinant inbred mouse strains. Moreover, the role of lipid microenvironment, glycosylation and various intracellular components on the ability of ethanol to modulate the channel function will be examined using a solubilized and purified receptor complex derived from rodents selectively bred for differences in ethanol sensitivity. It is anticipated that these studies will provide insight into the neural and genetic mechanisms responsible for sensitivity to alcohol. This shall in turn enable us to better understand the mode of inheritance of certain behavioral and neurochemical responses to alcohol. Further, these studies will expand our knowledge of the regulation and function of GABA/BDZR Cl- channel system.