药物成瘾是一种长期的、具有强烈的复吸特性的脑疾病。该疾病往往表现为强迫性的药物渴求和药物滥用。药物滥用已经变成了一个社会性的健康问题，影响着社会的各个方面。在本研究中，为了更好的理解药物成瘾的机制，我们做了两方面的工作。首先，我们探究了暂时性的失活脑岛皮层对于吗啡诱导的CPP的表达的影响以及重复性的消退（暴露在吗啡注射的环境中，而不给与药物注射）对于吗啡诱导CPP的影响，其次，我们应用RNAseq技术进行了转录组分析，来研究吗啡和吗啡相关的因素导致的差异基因表达及相关的基因网络变化。 CPP（条件化位置偏好）可以用来模拟药物相关因素导致的药物探寻行为。实验早期，我们建立了一个由三个房间组成的猕猴吗啡CPP装置，并且成功的应用递增剂量的吗啡建立了吗啡诱导的CPP。有很多报道表明脑岛与很多药物的成瘾有着密切的关系。为了检测脑岛在吗啡CPP中的作用，我们对七只猕猴进行了脑岛双边套管植入。这些猕猴成功建立吗啡CPP之后，在CPP检测之前五分钟，我们对其脑岛进行了40ul 5% 利多卡因溶液注射来暂时失活脑岛功能。结果发现，相对于脑岛注射盐水组，微注射利多卡因并不能影响吗啡CPP的表达。在接下来的75±0.2个月的时间内，我们对实验猕猴进行了6次CPP检测，来探究吗啡相关的记忆。在这6次CPP检测中，猕猴对于吗啡房间的偏好分数虽然有一个下降的趋势，但是即使在最后一次检测，吗啡诱导的CPP仍然是显著的。这些结果表明在猕猴中吗啡相关的记忆对于重复性的消退有着极大的抵抗性。虽然我们的结果没能表明脑岛参与了吗啡相关的CPP，但是吗啡相关记忆可以维持6年时间的结果提醒我们，在应用消退治疗的方法来治疗药物成瘾时，我们要慎重考虑。 另一方面，对于药物成瘾和药物复吸的分子机制的研究，一直以来都不够透彻。近年来，基因组学、遗传学和相关测序技术（微阵列和转录组测序）的迅猛发展，使我们可以找到很多影响成瘾行为的候选基因。为了更好的理解吗啡成瘾的机制，我们进行了猕猴转录组测序，来试图找到一些吗啡和吗啡相关因素导致的差异表达基因和改变的基因网络。在这部分实验中，我们找到了一些与吗啡成瘾相关的基因和通路。尽管这部分的结果需要进一步的实验来进行功能验证，我们的数据第一次提供了猕猴中吗啡导致的脑组织的转录组水平变化的实验证据。; Drug addiction is a chronic, relapsing disease characterized by compulsive drug seeking and bouts of intense drug craving. Drug abuse has become a major public health problem that impacts society on multiple levels. In this study, to better understanding the drug addiction, we did two different aspects of work. First, we investigated whether expression of morphine-induced CPP can be attenuated by inhibiting activity of insular cortex or by repeated unreinforced exposures to the CPP test. Second, we conducted a transcriptomic analysis using RNA sequencing to assess the differential gene expression induced by morphine and morphine associated cues. Cue-induced drug seeking can be modeled using the conditioned place preference (CPP). In the early stage of the study, we created a three-rooms CPP apparatus and successfully established morphine induced conditioned place preference (CPP) using increasing doses of morphine in rhesus monkeys. The insula has been demonstrated to be involved in addiction to several drugs of abuse. To test its role in morphine CPP, bilateral cannulae were implanted into the insula in seven adult monkeys. After the monkeys established morphine CPP, their insulae were reversibly inactivated by bilateral microinjection with 5% lidocaine (40 ul) prior to the post-conditioning test (expression) of CPP using a within-subject design. The microinjections of lidocaine failed to affect CPP expression when compared to saline injections. We subsequently investigated morphine-associated memory during six episodes of CPP tests performed in these monkeys over the following 75±0.2 months. While the preference score showed a declining trend with repeated testing, morphine-induced CPP was maintained even on the last test performed at 75 months post-conditioning. This observation indicated strong resistance of morphine-induced memories to extinction in rhesus monkeys. Although these data do not confirm involvement of insula in morphine-induced CPP, our observation that drug-associated memories can be maintained over six drug-free years following initial experience with morphine has important implications for treatment of drug addiction using extinction ?therapy. From another point of view, the underlying molecular mechanisms for drug addiction and relapse remain undefined. Recent progress in genomics, genetics and related sequencing technique (microarrays or RNA-Seq) have led to the identification of a large number of potential candidate genes influencing addiction behaviors. To gain further insight into the mechanisms of morphine addiction, we conducted a transcriptomic analysis using RNA sequencing to assess the differential gene expression and altered gene network induced by morphine and morphine associated cues in monkeys. In this part of study, we have found some genes and pathway associated with morphine addiction. Although this part of results need further functional validation, these data provide the first evidence for the morphine in modulating the transcriptional profile of the brain tissues of monkey.
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