补阳还五汤对大鼠脑缺血再灌注损伤后血脑屏障的影响

Effect of Buyang Huanwu Decoction on Blood Brain Barrier after Cerebral Ischemia and Reperfusion Injuries in Rats

目的观察补阳还五汤对大鼠脑缺血再灌注损伤后血脑屏障的影响并探讨其影响机制。方法48只SD大鼠随机分为3组:①假手术组(n=16);②对照组(n=16);③补阳还五汤组(n=16)。线栓法制作大鼠脑缺血再灌注模型,再灌注48 h后干湿重法测定缺血脑组织含水量,经股静脉注射伊文思蓝观察血脑屏障的通透性,取缺血脑组织提取总RNA和蛋白质分别应用逆转录聚合酶链反应和Western杂交技术检测基质金属蛋白酶9的转录及表达情况,同时电镜观察血脑屏障的变化。结果脑缺血再灌注48 h,对照组缺血侧脑含水量明显升高,伊文思蓝含量也明显增加,电镜观察发现血脑屏障破坏严重,基质金属蛋白酶9的转录与表达也较假手术组显著增加;而应用补阳还五汤处理的大鼠其缺血脑组织含水量明显减少,缺血侧伊文思蓝含量较对照组也明显降低(P<0.05),同时电镜观察到血脑屏障的破坏减轻,而基质金属蛋白酶9 mRNA和蛋白表达水平也明显低于对照组。结论对大鼠脑缺血再灌注损伤后的血脑屏障具有保护作用,其作用机制可能是通过抑制基质金属蛋白酶9的转录和表达来实现的。

Aim To investigate the effect of Buyang Huanwu Decoction on blcod-brain barrier of cerebral ischemia and reperfusion rats, and explore the mechenism of the decoction. Methods 48 normal male SD rats were distributed randomLy to 3 groups： ①Sharn-operation （ n = 16） ; ②Control （ n = 16） ; ③Buyang Huanwu Decoction （ n = 16）. Cerebral ischemia and reperfusion rat models were made using the method of thread inserting right middle cerebral artery occlusion（ MCAO）, The brain water content were measured 48 h after reperfusion. At the same time, The permeability of blcod-brain barrier was observed with electron microscope and by detecting the content of Evans Blue leaked out the brain tissue of ischemic side. The expression of MMP-9 in different groups was detected by Western Blotting, The transcription of MMP-9 mRNA was detected by RT-PCR. Results 48 h After erebral ischemia and reperfusion injuries, the content of brain water and Evans Blue leaked out the brain tissue of ischemie side increased obviously, The breakdown of blood-brain barrier was severe on electron microscope, the transcription and expression of MMP-9 also increased obviously. However, Buyang Huanwu Decoction can subtract the content of brain edema （ P 〈 0.05） and Evans blue （ P 〈 0.01 ）, relieve the breakdowm of blood-brain barrier on electron microscope.The transcription and expression of MMP-9 were decreased in BYHWD group contrasted with control group（ P 〈 0.05 ）. Conclusion BYHWD has the protective effect on BBB in the model rats of cerebral ischemia and reperfusion injuries. The mechanism may he by restrainning the expression and transcription of MMP-9.