正常猕猴与树鼩神经系统和免疫系统组织中大麻素与阿片受体的表达

为应用猕猴和树鼩动物模型研究毒品成瘾对神经/免疫系统的影响提供基础数据,对大麻素及阿片受体在正常猕猴和树鼩神经系统和免疫系统的表达进行初步确定.采集正常猕猴和树鼩新鲜组织(皮质、小脑、脑干、海马、脊髓、脾脏),应用半定量逆转录PCR和实时定量PCR的方法检测大麻素与阿片受体mRNA在猕猴和树鼩各组织中的表达情况.猕猴脑部各区包括脾脏均表达大麻索受体1(CNR1),而大麻素受体2(CNR2)只表达于脾脏内.三类阿片受体中,mu(μ)受体表达最为广泛,在以上各组织中均有表达;delta(δ)受体表达的组织最少,只在海马表达;kappa(κ)受体表达介于两者之间,分别在皮质、小脑、脑干、脊髓中表达.在树鼩组织中,CNR1和CNR2表达于整个大脑重要脑区中,且CNR1表达量高于同一区域内CNR2表达的鼍:脾脏中CNR2的表达较高,而CNR1不表达.三类阿片受体只有检测到μ受体在脑部与脾脏表达,且在各个脑区的表达量明显高于脾脏的表达量;δ体和κ受体在被检各个组织中均无表达.总体而言,两种大麻素受体在猕猴和树鼩体内表达情况与人类和鼠的情况类似,而三类阿片受体在猕猴体内表达情况与人类吏为接近.猕猴和树鼩可能可用于人类毒品成瘾的研究;猕猴在某些神经受体的表达更接近人类,其在研究毒品成瘾的机理和对免疫系统的影响方面仍有不可替代的地位.

Expression of cannabinoid and opioid receptors in nervous as well as immune systems of Macaca mulatta and Tupaia belangeri

To make Macaca mulatta and Tupaia belangeri as experimental animals for studying functions of opioid and cannabinoid receptors in drug addiction, we examined expression of the opioid and cannabinoid receptors in nervous and immune system of the two animals. We dissected normal adult M. mulatta and T. belangeri, collected tissues of cortex, cerebellum, brain stem, hippocampus, spinal cord, and spleen, and then applied the semi-quantitative PCR and real-time quantitative PCR methods to investigate the mRNA expression levels of the opioid and cannabinoid receptors in these tissues. In M. mulatta, the cannabinoid receptor 1 (CNR1) mRNA was expressed in the all tissues; in contrast, the cannabinoid receptor 2 (CNR2) mRNA was only present in the spleen. The mu opioid receptor (MOPR) was detected in all tissues, and the kappa opioid receptor (KOPR) was found in the cortex, cerebellum, brain stem, and spinal cord, but not in hippocampus and spleen. However, the delta opioid receptor (DOPR) was restrictively expressed in the hippocampus. In T. belangeri, CNR1 and CNR2 were expressed in the five regions of the brain. CNR2, but no CNR1, was also detected in the spleen. MOPR was expressed in all examined tissues, and its expression levels in the brain were higher than that in the spleen. DOPR and KOPR were not found in all tissues. Taken together, the expression profiles of cannabinoid receptors in human being, M. mulatta, T. belangeri, and rat were similar, and the expression patterns of the opioid receptors in M. mulatta were more close to human beings. The opioid and cannabinoid receptors were expressed in the tissues of nervous and immune systems of M. mulatta and T. belangeri, and both animals could be used for studying drug addiction. Macaca mulatta is still the best experimental animal for drug addiction research because it shows very similar expression profiles of these receptors to human beings.