体外LPS诱导血管内皮细胞通透性改变及其与连接蛋白43的关系

Effect of LPS on vascular permeability of vascular endothelial cells and role of connexin43 in the process

目的研究缝隙连接蛋白(connexin,Cx)43在脂多糖(lipopolysaccharide,LPS)诱导的大鼠血管内皮细胞(vascular endothelial cell,VEC)通透性中的表达变化及其意义。方法以1、2、3、4μg/ml LPS刺激原代培养的大鼠VEC,观察作用15、30 min,1、2、3、4、5、6、7 h后VEC增殖活力和通透性的变化;2μg/ml LPS刺激VEC后,采用RT-PCR和Western blot等方法检测Cx43的表达变化;分析VEC通透性和Cx43表达之间的相关性。结果 1、2μg/ml的LPS对VEC增殖活力无明显影响,3、4μg/ml的LPS明显降低了VEC的增殖(P<0.01);2μg/ml的LPS能够较好地模拟脓毒性休克的血管高通透性(P<0.01);用此浓度的LPS刺激VEC后Cx43的mRNA和蛋白表达均逐渐降低(P<0.01);Cx43的表达与LPS引起的VEC通透性改变呈负相关关系(r=-0.877,P<0.01)。结论 Cx43可能参与了脓毒性休克后VEC通透性的调节;Cx43可能具有抑制脓毒性休克后血管内膜通透性的作用。[关键词]脓毒性休克;脂多糖;血管通透性;血管内皮细胞;

Objective To investigate the expression and significance of connexin43（Cx43） in the increased vascular permeability induced by LPS.Methods Rat vascular endothelial cells（VECs） were primary isolated from normal SD rats＇ superior mesenteric arteries（SMAs）,and then cultured with treatment of 1,2,3 or 4 μg/ml LPS for 15 and 30 min,and 1,2,3,4,5,6 or 7 h.Cell vitality and permeability were determined with MTT assay and Transwell chamber technique respectively.The mRNA and protein expression of Cx43 were determined in the cells after 2 μg/ml LPS treatment.Results LPS at 1 and 2 μg/ml didn＇t change the cell vitality,while 3 and 4 μg/ml LPS diseased it obviously（P0.01）.LPS of 2 μg/ml increased the cell permeability（P0.01）.The expression of Cx43 at mRNA and protein levels was gradually decreased after 2 μg/ml LPS treatment.VECs＇ permeability and the expression of Cx43 had a negative correlationship.Conclusion Cx43 is involved in the regulation of vascular permeability following septic shock.Cx43 may be used to attenuate vascular permeability in septic shock.