摘要
目的探讨血管紧张素Ⅱ对内皮细胞肌动蛋白骨架的影响及其作用机制。方法血管紧张素Ⅱ(10-6mol/L)处理人脐静脉内皮细胞不同时间(0、5、15、30及60 min)。激光共聚焦显微镜下观察细胞纤维状肌动蛋白骨架的形态学变化。Western blotting检测丝裂原活化蛋白激酶磷酸化水平。结果正常组内皮细胞的纤维状肌动蛋白主要富集于细胞膜周边,分布均匀。血管紧张素Ⅱ处理组细胞膜周边的纤维状肌动蛋白消失,胞浆中出现密集的应力纤维,细胞间隙形成,且呈明显的时间依赖性。血管紧张素Ⅱ上调p38丝裂原活化蛋白激酶、c-Jun氨基末端激酶和热休克蛋白27的磷酸化水平,但对细胞外信号调节激酶无明显影响。p38丝裂原活化蛋白激酶特异性抑制剂SB203580阻断血管紧张素Ⅱ引起的纤维状肌动蛋白重排和细胞间隙形成。c-Jun氨基末端激酶特异性抑制剂SP600125则无明显作用。结论血管紧张素Ⅱ通过激活p38丝裂原活化蛋白激酶/热休克蛋白27信号通路引起内皮细胞的纤维状肌动蛋白重排,导致细胞骨架损伤。
Aim To study the effect of angiotensin Ⅱ（AngⅡ） on cytoskeleton rearrangement of endothelial cells and the mechanisms within it.Methods Human umbilical vein endothelial cells（HUVEC） were treated with AngⅡ（10-6 mol/L） for different time points.The morphological images of filamentous actin（F-actin） cytoskeleton were observed with confocal laser scanning microscope.The phosphorylated protein expression of mitogen-activated protein kinase（MAPK） was tested by Western blotting.Results F-actin was mainly enriched along the cell membrane,and well distributed in normal HUVEC;After treatment with AngⅡ,most of the peripheral fibers disappeared,dense stress fibers were observed in the cytoplasm and paracellular gaps formed in a time-dependent manner.AngⅡ increased the phosphorylation of p38 MAPK,JNK1/2 and HSP27,but not ERK1/2.Furthermore,SB203580（a p38 MAPK specific inhibitor） completely attenuated AngⅡ-induced formation of actin stress fibers and paracellular gaps.In contrast,SP600125（a JNK1/2 specific inhibitor） had no effect on these responses.Conclusion AngⅡ induces F-actin rearrangement in HUVEC through the activation of p38 MAPK/HSP27 pathway,which results in cytoskeletal damage.
出处
《中国动脉硬化杂志》
CAS
CSCD
北大核心
2010年第2期117-120,共4页
Chinese Journal of Arteriosclerosis
