摘要
目的研究Ras基因家族成员A(RhoA)的特异性抑制剂C3胞外酶(exoenzyme)对缓激肽诱导的血肿瘤屏障通透性的作用。方法应用C3 exoenzyme预处理大鼠原代脑微血管内皮细胞后,测量跨内皮阻抗值(TEER)、辣根过氧化物酶(HRP)流量,分析血肿瘤屏障的通透性的改变;应用Western blot检测紧密连接相关蛋白(ZO-1)的表达;应用免疫荧光法观察原代大鼠脑微血管内皮细胞紧密连接相关蛋白ZO-1和丝状肌动蛋白(F-actin)结构和分布的改变。结果 C3 exoenzyme显著抑制缓激肽诱导TEER值的降低、HRP流量的升高及ZO-1的表达,抑制ZO-1由内皮细胞的边缘向细胞质转移,抑制丝状肌动蛋白由细胞膜边缘向细胞中央区分布,分布于细胞边缘的F-actin明显增加,应力纤维形成明显减少。结论 RhoA能够介导缓激肽开放血肿瘤屏障。
Objective To investigate the effect of C3 exoenzymea,specific Ras homolog gene family member A(RhoA)inhibitoro,n bradykinin(BK)-induced increase in blood-tumor barrier(BTB)permeability.Methods Rat brain microvascular endothelail cells(RB-MECs)were pretreated with C3 exoenzyme and then treated with BK for 15 minutes.Horseradish peroxidase(HRP)flux and TEER assays were employed to reveal BTB permeability.The protein expression level of ZO-1 was observed by Western blot.The stress fiber formation and distribution of filamentous actin(F-actin)and ZO-1 were assessed by immunofluorescence microscopy.Results C3 exoenzyme could par-tially inhibit endothelial leakage and restored normal TEER values in RBMECs.The expression level of ZO-1 protein decreased significantly and it was prevented by C3 exoenzyme.C3 exoenzyme inhibited BK-induced relocation of ZO-1 from cellular borders into the cytoplasm as well as stress fiber formation in RBMECs.Conclusion RhoA plays a key role in BK-induced openning of blood-tumor barrier.
出处
《中国医科大学学报》
CAS
CSCD
北大核心
2011年第2期97-100,共4页
Journal of China Medical University
基金
国家自然科学基金资助项目(30872656,30670723,30973079)
高等学校博士学科点专项科研基金资助项目(20092104110015)
沈阳市科学技术计划项目(1072033-1-00,1081266-9-00)