摘要
目的探讨亚甲基蓝对大鼠局灶性脑缺血再灌注引起血脑屏障破坏的保护作用。方法雄性Sprague-Dawley大鼠18只随机分为假手术组(n=6)、模型组(n=6)和亚甲基蓝组(n=6)。用线栓法制备大鼠左侧大脑中动脉栓塞1 h再灌注模型。亚甲基蓝组于再灌注即刻及再灌注2 h分别静脉给予亚甲基蓝3 mg/kg、1.5 mg/kg;模型组给予相同体积的生理盐水;假手术组手术操作与模型组相同,不插入线栓,不静脉注射药物。再灌注47 h后HE染色观察大鼠脑缺血周边皮层组织学结构,白蛋白免疫组化染色法检测血脑屏障通透性的变化,免疫组化染色法和免疫荧光双标染色法检测胶质原纤维酸性蛋白(GFAP)和水通道蛋白-4(AQP-4)的表达。结果 HE染色显示,模型组缺血周边大脑皮层的细胞和血管形态不完整,而亚甲基蓝组病理变化减轻;模型组白蛋白、GFAP和AQP-4表达均明显高于假手术组(P<0.01),亚甲基蓝组白蛋白、GFAP、AQP-4表达均低于模型组(P<0.05)。免疫荧光双标染色显示,AQP-4与GFAP在星形胶质细胞上共定位。结论亚甲基蓝可能是通过减轻胶质细胞增生及下调AQP-4表达来改善局灶性脑缺血再灌注损伤引起的血脑屏障破坏。
Objective To investigate the protective effect of methylene blue （MB） on blood-brain barrier （BBB） injury after focal cerebral ischemia-reperfusion in rats. Methods 18 male Sprague-Dawley rats were randomly divided into sham-operated group （n=6）, model group （n=6） and MB treatment group （n=6）. The left middle cerebral arteries were occluded for 1 hour and reperfused. MB was infused intravenously immediately after reperfusion （3 mg/kg） and again 2 hours post-reperfusion （1.5 mg/kg）, while normal saline was administered in the model group. The sham-operated group was treated as same as the model group without occlusion and infusion. HE staining was used to observe the histological injury in the cortex around the infarcted region 47 hours after reperfusion, while albumin immunohistochemistry was used to evaluate the permeability of the BBB, and immunohistochemistry and double immunofluorescence staining were used to examine the expressions of glial fibrillary acidic protein （GFAP） and aquaporin-4 （AQP-4）. Results HE staining showed that cells and blood vessels were not intact in the cortex around the infarcted region in the model group and they were better in the MB treatment group. The expressions of the albumin, GFAP and AQP-4 were higher in the model group than in the sham-operated group （P〈0.01）, and were lower in MB treatment group than in the model group （P〈0.05）. The double immunofluorescence staining showed the colocalization of GFAP and AQP-4 in the astrocytes. Conclusion MB may ameliorate the BBB disruption induced by focal cerebral ischemia-reperfusion through reducing glio- cyte proliferation and down-regulation of AQP-4 expression in rats.
出处
《中国康复理论与实践》
CSCD
北大核心
2016年第2期125-131,共7页
Chinese Journal of Rehabilitation Theory and Practice
基金
国家自然科学基金项目(No.81271286
No.81228009)
