MU OPIOID RECEPTOR GENE IN HEROIN ADDICTS

海洛因（二乙酰吗啡）成瘾是一个主要的社会问题， 影响了美国一百多万人 在身体和 在大脑中，海洛因被水解成吗啡，吗啡作用于μ阿片样物质 受体，并导致欣快效应，从而赋予 加强药物的性质，并有助于开发 成瘾 海洛因成瘾可以通过治疗来控制，主要是 美沙酮维持，但海洛因成瘾的生物学基础， 关于μ受体的遗传多样性和这种遗传多样性的影响， 受体功能的多样性。随着人类μ阿片类药物的克隆 受体，现在有可能研究之间的序列变异 不同的个体，并将它们与受体的变化相关联， 功能 这一提议的假设是，基因组中的DNA序列变异 受体基因存在于人类中，这种自然发生的多态性 影响受体对吗啡的反应为了验证这一 假设，血液样本将收集海洛因成瘾者和正常人 志愿者建立一个储存库， 淋巴细胞系，在印第安纳州储存一式两份样本 一个在洛克菲勒大学。多态性在这些 个体将通过扩增μ受体编码来确定 使用PCR测序并筛选序列变异。的相关性 多态性和受体功能变化之间的关系将通过以下方法进行研究： 突变所述μ受体cDNA以匹配所述多态性。 这些变异 受体将在培养的细胞中表达，并测试其 在配体显带中的功能，腺苷酸环化酶活性的抑制，以及 激活钾离子通道。吗啡效应的时间过程将 研究急性刺激、慢性暴露和急性戒断。 此外，将检查蛋白激酶对受体功能的调节 作为药物诱导细胞变化的分子机制。 这是研究生物学意义的一种新方法 麻醉受体通过使用一组控制良好的受试者。与 健康和药物滥用史的详细信息，详细的分子 对每个受试者的μ受体基因的分析应该会产生有价值的结果 关于μ受体的遗传和功能多样性的信息， 提供其结构-功能关系的直接评估。 此外，这种方法可以很容易地应用于其他蛋白质 参与滥用药物的生理途径，产生重要的 关于这些蛋白质的生物学机制的信息，以及 提供了一个关于药物成瘾的生物学基础的广泛视角。

Addiction to heroin (diacetylmorphine) is a major social problem, affecting over a million people in the United States. In the body and brain, heroin is hydrolyzed to morphine, which acts at the mu opioid receptor and results in an euphoric effect, thus conferring the reinforcing properties of the drug and contributing to the development of addiction. Heroin addiction can be managed through treatment, primarily methadone maintenance, but the biological basis of heroin addiction, with respect to the genetic diversity of the mu receptor and the impact of such diversity on receptor function. With the cloning of the human mu opioid receptor, it is possible now to study the sequence variations among different individuals and correlate them with changes in receptor function. The hypothesis for this proposal is that DNA sequence variations in the mu receptor gene exist in humans, and such natural occurring polymorphisms affect the receptor function in response to morphine. To test this hypothesis, blood samples will be collected from heroin addicts and normal volunteers to establish a repository that contains DNA and viable lymphocyte cell lines, storing duplicate samples with one set at Indiana University and one at Rockefeller University. Polymorphisms in these individuals will be determined by amplifying the mu receptor coding sequence using PCR and screening for sequence variations. A correlation between polymorphisms and changes in receptor function will be examined by mutating the mu receptor cDNA to match the polymorphisms. These mutated receptors will be expressed in cultured cells, and tested for their functions in ligand banding, inhibition of adenylyl cyclase activity, and activation of a potassium channel. The time course of morphine effect will be studied upon acute stimulation, chronic exposure, and acute withdrawal. Also, modulation of receptor function by protein kinases will be examined as a molecular mechanism for drug-induced changes in the cell. This is a novel approach for studying the biological significance of narcotic receptors. By using a well-controlled group of subjects. with detailed information on health and drug abuse history, detailed molecular analysis of each subject's mu receptor gene should yield valuable information on the genetic and functional diversity of the mu receptor and provide a direct assessment of its structure-function relationship. Furthermore, this approach can be readily applied to other proteins involved in the physiological pathways of abused drugs, yielding important information regarding the biological mechanisms for these proteins, and provide a broad perspective on the biological basis of drug addiction.