伏隔核毁损对MAP模型大鼠行为及脑内DA受体的影响

目的 探讨立体定向伏隔核毁损对甲基苯丙胺（MAP）模型大鼠行为学及不同脑区多巴胺D2受体表达的影响。方法 将80只SD大鼠随机分为对照组、模型组、假手术组和手术组，每组各20只。经腹腔注射MAP制备精神分裂症模型，采用立体定向一直流电毁损伏隔核，观察大鼠刻板行为变化；并采用原位杂交法观察额叶、颞叶、边缘区及脑干部位的D2受体表达。结果 与对照组比较，模型组及假手术组大鼠刻板行为评分及各个脑区D2受体表达均显著性增加；与模型组及假手术组比较，手术组大鼠刻板行为评分及各脑区DA受体阳性细胞数目均显著性减少。结论 伏隔核毁损可能通过抑制MAP诱发的脑内D2表达亢进而改变其行为学异常。

The effect of nucleus accumbens lesion on behavior and expression of cerebral dopamine receptor in methamphetamine-treated rats

Objective To explore the effects of stereotactic lesion to the nucleus accumbens on the behavior and expression of dopamine receptor D2(DRD2) in special areas of the brain in methamphetamine(MAP)-treated rats.Methods Eighty Sprague-Dawley rats were equally divided into four groups: normal control(NC),MAP-treated alone,MAP + sham-lesioned,and MAP + lesion to the nucleus.The rat model of schizophrenia was prepared by MAP injection i.p.and the nucleus lesioned by direct current to observe the changes in stereotypic behavior of MAP + lesion rats.Expressions of DRD2 in the prefrontal lobe and temporal lobe and limbic system and brain stem were then detected by in situ hybridization.Results Compared with the control group,there were remarkable behavior changes and increase of DRD2 expressions in the above mentioned areas in the MAP-treated alone and MAP + sham-lesioned groups;and compared with MAP-treated alone and MAP + sham-lesioned groups,the score of the behavior and DRD2 expression was decreased obviously.Conclusion Nucleus accumbens lesion can improve stereotyped behavior in MAP rats,which may be due to restrain the hyperexpression of DRD2 induced by MAP.