诱发癫痫持续状态后基质金属蛋白酶-2在小鼠海马与皮层中的表达

Expressions of matrix metalloproteinases-2 in the hippocampus and cortex of mouse following status epilepticus

摘要:

目的：观察氯化锂-匹罗卡品所致癫痫持续状态（status epilepticus，SE）小鼠皮层和海马基质金属蛋白酶-2（matrix met－alloproteinases-2，MMP-2）的表达变化，探讨 MMP-2在癫痫发病机制中的作用。方法：选用成年雄性C57/BL6小鼠 48只，并随机分成实验组和对照组。实验组小鼠腹腔注射氯化锂-皮罗卡品制备SE模型，在确定模型成功后8 h采取动物标本进行检测。使用 RT-PCR测定 MMP-2 mRNA含量变化，Western blot检测 MMP-2蛋白表达变化，免疫组化观察 MMP-2分别在海马与皮层的分布规律与特点。结果：（1）海马组织中，对照组与实验组MMP-2 mRNA的表达分别为 0.155 5±0.018 1和 0.743 1±0.014 4，皮层组织中的表达分别为0.204 9±0.018 5和0.871 6±0.037 0，实验组MMP-2 mRNA的表达均比对照组高，差异有统计学意义（t=-45.60，P=0.000；t=-71.83，P=0.000）。（2）MMP-2蛋白水平的表达，在海马组织中分别为 0.084 5±0.009 6和 0.728 4±0.245 1，在皮层组织中对照组与实验组分别为 0.155 6±0.003 9和0.912 5±0.027 7，实验组MMP-2蛋白的表达均明显高于对照组，差异有统计学意义（t=-76.52，P=0.000；t=-6.99，P=0.000）。（3）免疫组化结果显示，实验组MMP-2在皮层广泛表达，在海马的表达增加主要以 CA1、齿状回、CA3区为主。结论：SE后小鼠海马及皮层内MMP-2在mRNA和蛋白水平的表达均明显升高，表达增加的区域以海马CA1、齿状回及CA3区为主，提示 MMP-2与癫痫的发生、发展可能有着密切的关系。

Abstract:

Objective：To observe the expression of matrix metalloproteinases-2（MMP-2） in the cortex and hippocampus of LiCl-pilo－carpine induced mice status epilepticus（SE） and to explore the role of MMP-2 in the pathogenesis of epilepsy. Methods：Totally 48 adult male C57/BL6 mice were randomly divided into experimental group and control group. Intraperitoneal injection of the lithium chloride and pilocarpine was applied in experimental mice of epilepsy to induce seizures and animal specimens were made for testing at 8 h after SE. MMP-2 mRNA contents were determined by RT-PCR，MMP-2 protein expressions were detected by Western blot and distribution and characteristics of MMP-2 in hippocampus and cortex were detected by immunohistochemical method. Results：①mRNA expressions of MMP-2 in control group and experimental group were 0.155 5±0.018 1 and 0.743 1±0.014 4 respectively in hippocampus and were 0.204 9±0.018 5 and 0.871 6±0.037 0 respectively in cortex. mRNA expressions of MMP-2 in the hippocam－pus and cortex of experimental mice were significantly higher compared with those in control group（t=-45.60，P=0.000；t=-71.83，P=0.000）. ②Protein expressions of MMP-2 in control group and experimental group were 0.084 5±0.009 6 and 0.728 4±0.245 1 re－spectively in hippocampus and were 0.155 6±0.003 9 and 0.912 5±0.027 7 respectively in cortex. Protein expressions of MMP-2 in hippocampus and cortex of experimental mice were significantly higher compared with those in control group（t=-76.52，P=0.000；t=-6.99，P=0.000）. ③Immunohistochemical results showed that the MMP-2 was widely expressed in cortex in experimental group. MMP-2 expression was increased in hippocampus，mainly in the CA1，dentate gyrus and CA3 region. Conclusions：mRNA and protein expressions of MMP-2 in the hippocampus and cortex of mice are significantly increased after SE，mainly in CA1，dentate gyrus and CA3 region，which indicats that MMP-2 has close relationship with occurrence and process of epilepsy.