尾加压素增加血管平滑肌细胞粘着斑激酶的含量和活力  

Content and activity of the focal adhesion kinase in cultured vascular smooth muscle cells enhanced by urotensin Ⅱ

作　　者：彭旭[1] 尹航[1] 汪丽蕙[1] 柴三葆[1] 苏加林[1] 唐朝枢[1] 

机构地区：[1]北京医科大学第一医院心内科,北京100034

出　　处：《生理学报》2000年第6期455-458,共4页Acta Physiologica Sinica

基　　金：SupportedbytheGrantofNationalDorctorateEducation (No 96 0 2 40 14 )

摘　　要：在体外培养的血管平滑肌细胞上 ,采用蛋白印迹杂交免疫沉淀的方法 ,研究尾加压素Ⅱ (UⅡ )与粘着斑激酶 (FAK)介导的信号传导之间的关系。结果表明 ,UⅡ在 10 -8、10 -7和 10 -6mol/L的浓度时 ,可分别使FAK活力增加 2 2、3 0 4和 0 73倍 ;加入UⅡ (10 -7mol/L) 5min后 ,FAK活力增加 95 % ,但与对照组相比无显著性差异(P >0 0 5 ) ,刺激 10min后 ,FAK活力升高 3 7倍 ,和对照组相比有显著性差异 (P <0 0 5 )。至 30min时活力显著升高 ,较对照组增加 4 8倍 (P <0 0 1)。UⅡ刺激平滑肌细胞 30min内 ,FAK的蛋白含量无明显变化 ;在UⅡ作用 2h后 ,FAK的含量增加 36 % ,至 4h达高峰 ,与对照组相比增加 5 3% ,6h后降低 ;细胞松弛素B不能抑制UⅡ对FAK的激活 ;丝裂素活化蛋白激酶的抑制剂PD980 5 9(5 0 μmol/L) ,钙调素依赖性蛋白激酶的抑制剂W7(5 0 μmol/L) ,对FAK的激活无影响 (P >0 0 5 ) ;蛋白激酶C的阻断剂H7(5 0 μmol/L) ,可与UⅡ发生协同作用 ,使FAK活力较单纯UⅡ组增加 1 98倍。因此 ,UⅡ与FAK介导的信号转导途径之间存在着密切的关系 ,且这种关系不依赖于细胞骨架的完整性 ,与蛋白激酶C介导的信号转导途径有密切的关系。Urotensin Ⅱ (UⅡ) is the most potent vasoconstrictor identified in vivo, which plays an important role in the smooth muscle cell proliferation in atherosclerosis. All available information suggests that focal adhesion kinase (FAK) is at the crossroads of multiple signaling pathways and is essential for cell proliferation. But the effect of UⅡ on the FAK mediated signal transduction pathway is unclear. In this study, FAK content and tyrosine phosphorylation were assessed by Western blot and immunoprecipitation in cultured rat vascular smooth muscle cells. Increased protein tyrosine phosphorylation was observed within 5 min of UⅡ 10 -7 (mol/L) addition and was maximal by 30 min, while FAK protein content showed no change during the first 30 min but it increased at 2 h reaching a plateau by 4 h, and decreased after 6 h. In addition, the elevated phosphorylation of FAK was detected upon UⅡ stimulation at 10 -8 mol/L, being maximal at 10 -7 mol/L, but decreased at 10 -6 mol/L. Treatment of the cells with cytochalasin B (50 μmol/L), which disrupted the organization of cytoskeleton, had no influence on the increased FAK tyrosine phosphorylation in response to UⅡ stimulation. In order to study the relationship between FAK and mitogen activated protein kinase, calmodulin and protein kinase C, selective inhibitors PD98059 (50 μmol/L), W7 (50 μmol/L) and H7 (50 μmol/L) were added following UⅡ treatment. Neither PD98059 nor W7 influenced the increased FAK tyrosine phosphorylation, but H7 further increased it. These findings indicate that FAK activation is independent of the integrity of cytoskeleton and closely related to protein kinase C, but had no relation with mitogen activated pro tein kinase and calmodulin.[WT5HZ]

关 键 词：粘着斑激酶 尾加压素 信号转导 血管平滑肌 活力 

分 类 号：R33[医药卫生—人体生理学]