醒脑静注射液对全脑缺血再灌注大鼠血脑屏障ZO-1表达的影响

目的:探讨醒脑静(XNJ)注射液对大鼠全脑缺血再灌注后血脑屏障通透性及紧密连接蛋白1(ZO-1)表达的影响。方法:采用改良Pulsinelli四血管闭塞法建立大鼠全脑缺血再灌注模型。将雄性Wistar大鼠随机分为4组,即假手术组、全脑缺血再灌注模型组、溶剂对照组和XNJ组。每组均在缺血再灌注后24 h、48 h和72 h处理。用干湿重法测定脑组织中水含量,分光光度计法检测脑组织伊文思蓝(EB)含量,Western blot检测大脑皮层的ZO-1蛋白含量。结果:缺血再灌注后24 h,模型组、溶剂对照组和XNJ组的脑组织含水量均显著高于假手术组(P0.05),但在缺血再灌注后48 h和72 h,模型组和溶剂对照组脑组织含水量显著高于XNJ组和假手术组(P0.05)。缺血再灌注后24 h,模型组、溶剂对照组和XNJ组大鼠脑组织内EB含量均高于假手术组(P0.05),缺血再灌注后48 h和72 h,假手术组和XNJ组的EB含量显著低于模型组和溶剂对照组(P0.05)。缺血再灌注后24h,模型组、溶剂对照组和XNJ组大鼠脑皮层中的ZO-1蛋白表达水平显著低于假手术组(P0.05),同样缺血再灌注后48 h和72 h,假手术组和XNJ组皮层中ZO-1蛋白含量显著高于模型组和溶剂对照组(P0.05)。结论:在缺血再灌注后的48 h和72 h,醒脑静注射液对血脑屏障具有保护作用,可能与醒脑静注射液上调ZO-1蛋白的表达有关。

Effects of Xingnaojing injection on expression of ZO-1 in blood-brain barrier after global ischemia-reperfusion

AIM: To investigate the effect of Xingnaojing (XNJ) injection on the permeability of blood-brain barrier (BBB) and zonula occludens-1 (ZO-1) protein expression after global ischemia-reperfusion in rats. METHODS: Improved Pulsinelli four-vessel occlusion method was adopted to establish the global ischemia-reperfusion model in the rats. Male Wistar rats were randomly divided into sham group, model group, solvent group and XNJ group. The observations were conducted at the time points of 24 h, 48 h and 72 h after ischemia reperfusion. The water content of the brain tissues was determined by dry-wet weight method, while the Evans blue (EB) content of brain tissue was detected by spectrophotometry. The protein levels of ZO-1 in the cerebral cortex were analyzed by Western blot. RESULTS: The water contents in the brain tissues in model group, solvent group and XNJ group were significantly higher than those in sham group (P<0.05) 24 h after ischemia reperfusion. However, the brain water contents in model group and solvent group were significantly higher than those in XNJ group and sham group (P<0.05) 48 h and 72 h after ischemia reperfusion. The EB contents in the brain tissues in model group, solvent group and XNJ group were entirely higher than that in sham group 24 h after ischemia reperfusion (P<0.05). The EB contents in sham group and XNJ group were significantly lower than those in model group and solvent group 48 h and 72 h after ischemia reperfusion (P<0.05). The protein expression of ZO-1 in the rat cerebral cortex in model group, solvent group and XNJ group was significantly lower than that in sham group 24 h after ischemia-reperfusion (P<0.05). Similarly, 48 h and 72 h after ischemia reperfusion, ZO-1 protein level in the cortex in sham group and XNJ group was significantly higher than that in model group and solvent group (P<0.05). CONCLUSION: At 48 h and 72 h after global ischemia-reperfusion, Xingnaojing injection play a protective role in blood-brain barrier and this role may be associated with the increase in ZO-1 protein expression by Xingnaojing injection.