心肺复苏大鼠脑基质金属蛋白酶9的表达和血脑屏障的变化

Exploration of Variety of Matrix Metalloproteinase 9 and Blood Brain Barrier in Cardiopulmonary Resuscitation Rats

【目的】探讨心肺复苏后早期大鼠脑组织基质金属蛋白酶9(MMP9)的表达和血脑屏障的变化规律。【方法】将80只大鼠随机分为假手术组(n=40)和复苏组(n=40)。假手术组仅进行麻醉和气管插管、血管穿刺,不进行窒息,复苏组用气管夹闭窒息法致使心跳骤停后进行复苏,其他与对照组相同,分别在0、3、9、24h和48h5个时间点处死大鼠后,取样,测定脑组织MMP9的表达、MMP9 mRNA、脑含水量与脑组织伊文思蓝含量的变化,电镜观察脑组织的超微结构。【结果】复苏组心肺复苏后3、9、24和48h脑组织MMP9表达明显高于假手术组,MMP9 mRNA含量与假手术组相比差异有统计学意义,脑含水量与假手术组比较明显升高,与假手术组比较,脑组织伊文思蓝含量明显升高;超微结构发生改变。【结论】在心肺复苏大鼠脑缺血模型中MMP9蛋白和MMP9 mRNA的表达明显升高;脑组织的脑含水量和伊文思蓝含量明显升高,血脑屏障受到破坏;电镜超微结构观察证实脑组织损伤明显;这些变化在心肺复苏后24h达高峰。

[Objective] To explore the variety of matrix metalloproteinase 9 （MMP9） and blood brain barrier （BBB） in cardiopulmonary resuscitation rats. [ Methods ] Eighty rats were randomly divided into 2 groups： the sham-operated group （n = 40） and the resuscitation group （n = 40）. The two groups were anaesthetized and endotracheally intubated, the resuscitation group was also induced to cardiac arrest by aphysia. Then the rats were put to death and samples were taken at immediate, 3 h, 9 h, 24 h, and 48 h. After that, the expression of MMP9, MMP9 mRNA, water content and Evans blue content in brain tissue were detected. Ultramicrostructure of brain tissue was observed with electron microscope. [ Results ] Compared to the sham-operated group, at 3 h, 9 h, 24 h and 48 b, the expression of MMP9 of resuscitation group was significantly changed. MMP9mRNA significantly increased. Water content statistically increased and so was Evans blue content. The change of ultramicrostructure in the resuscitation group at 3 h, 9 h, 24 h, and 48 h was obvious. [ Conclusion ] The expression of MMP9 and MMP9mRNA obviously increased in the cerebral ischemia model with CPR rats, and got to peak at 24 h. Water content and Evans blue content in brain tissue obviously increased in the cerebral ischemia model with CPR rats, BBB was destroyed, and the peak was 24 h. The injury of uhramicrostructure of brain tissue with electron microscope was obvious, and the peak was 24 h.