摘要目的 观察苯丙胺干预后小鼠额叶皮质内鼠双微体2(Mdm2)的表达情况.方法 雄性C57BL/6小鼠随机分为正常对照组(10只)、生理盐水组(10只)及苯丙胺组(40只).苯丙胺组又分为1、7、14和28 d 4个亚组,苯丙胺组腹腔注射苯丙胺2 mg·kg-1·d-1,1次/d;生理盐水组注射等体积生理盐水,正常对照组不予任何处理.建模期间对小鼠进行自主行为活动测试.免疫化学染色及Western印迹检测各组小鼠额叶皮质内Mdm2的表达情况.结果 苯丙胺7、14、28 d组小鼠的运动总路程、平均速度、最大运动速度、快速运动时间/总时间比正常对照组和生理盐水组增加,差异有统计学意义(P<0.05).免疫组化显示,与正常对照组和生理盐水组相比,苯丙胺组Mdm2免疫阳性产物灰度值明显降低,差异有统计学意义(P<0.05);苯丙胺14 d组较苯丙胺1 d组免疫阳性产物的灰度值进一步降低,差异有统计学意义[1 d(213.31±6.78),14 d(192.82±7.90),P<0.05].Western印迹结果显示,苯丙胺组小鼠额叶皮质Mdm2蛋白表达量较其他2组增强.结论 苯丙胺可引起小鼠额叶皮质Mdm2表达显著升高.

abstractsObjective To determine the expression of murine double minute 2 (Mdm2) in the frontal cortex of mice after intervention with Amphetamine. Methods Male C57BL/6 mice were randomly divided into the normal control group(n=10),normal saline group(n=10)and Amphetamine group(n=40). The Amphetamine group was divided into 1,7,14 and 28 d subgroups,and was intraperitoneally injected with 2 mg · kg-1 · d-1 Amphetamine,1 time/d. The normal saline group was injected with equal volume of normal saline,and the normal control group received no treatment. The autonomous behavior activities were tested during establishing the models. Immunohistochemistry and Western blotting were used to examine the Mdm2 expression in frontal cortex of the mice. Results The total moving distance,average speed, maximum speed,fast moving time/total time ratio in the 7,14 and 28 d Amphetamine subgroups were significantly increased compared with those in the normal control group and normal saline group,and there were statistically significant differences (P<0.05). Immumohistochemistry showed that the grey values of Mdm2-positive inummoreactive products in the Amphetamine group were significantly lower than those in the normal control group and normal saline group,and there were statistically significant differences(P<0.05). The grey values of the positive inummoreactive products in the Amphetamine 14 d subgroup was significantly decreased compared with those in the Amphetamine 1 d subgroup,and there were statistically significant differences[1 d(213.31 ± 6.78),14 d(192.82 ± 7.90),P<0.05]. The findings of Western blotting showed that Mdm2 protein expression in the frontal cortex was elevated in the Amphetamine group compared with that in the other two groups. Conclusion Amphetamine can significantly increase Mdm2 expression in thefrontal cortex of mice.