血管紧张素Ⅱ对培养人脐静脉内皮细胞PAI-1 tPA蛋白表达的影响

Effects of angiotensin Ⅱ on the expression of PAI-1 and tPA in cultured human umbilical vein endothelial cells

目的研究血管紧张素Ⅱ（AngⅡ）对人脐静脉内皮细胞（HUVECs）1型纤溶酶原激活物抑制剂（PAI-1）、组织型纤溶酶原激活剂（tPA）蛋白的释放及活性的影响.方法将不同浓度的AngⅡ（1 ×10-9～1×10-6mmol/L）与HUVECs共同孵育24h,以及将1×10-6 mol/LAngⅡ与HUVECs作用不同时间（0、4、8、12、24 h）后,用细胞酶联免疫法和发色底物法分别检测细胞培养液中PAI-1、tPA的含量及活性.结果1×10-6 mol/L AngⅡ作用HUVECs 24 h后,可使细胞分泌的PAI-1含量与对照组相比明显增高[（280±16）ng/ml vs（83±11）ng/ml,P＜0.01],PAI-1活性明显增高[（10.35±1.47）U/ml vs（5.65±0.44）U/ml,P＜0.01],AngⅡ虽也可刺激tPA含量增加[（102±4）ng/ml vs（70±6）ng/ml,P＜0.01],但PAI-1的增量是tPA增量的6～7倍[△（197±21）ng/mlvs △（31±6）ng/ml,P＜0.01],AngⅡ对tPA活性无影响[（0.97±0.05）U/ml vs（0.95±0.08）U/ml,P＞0.05];1×10-9～1～1×10-6 mol/L不同浓度的AngⅡ分别作用HUVECs 24 h,PAI-1含量增加、活性增加与AngⅡ呈浓度依赖性相关;1×10-6mol/L AngⅡ与HUVECs分别作用4～24 h,PAI-1含量及活性增加与AngⅡ作用于HUVECs的时间呈正相关.结论AngⅡ可促使HUVECs分泌PAI-1,并使其活性增加,AngⅡ虽亦可刺激tPA分泌,但作用弱于PAI-1,且对其活性无明显影响.

Objective To observe the effects of angiotensin Ⅱ （Ang Ⅱ） on plasminogen activator inhibitor-1 （PAI-1） and tissue type plasminogen activator （tPA） releasing and their activity in cultured human umbilical vein endothelial cells（HUVECs）. Methods Several groups of cultured HUVECs were incubated with Ang Ⅱ of 1 × 10^-9 ～1×10^-6 mol/L for 24 hours or with 1×10^-6 mol/L Ang Ⅱ for various times up to 24 hours.Then the antigens and activity of PAI-1 and tPA in the cultured medium were measured by enzyme linked immunosorbent assay（ELISA） and the indirect chromogenic assay. Result Compared to control, 1×10^-9 ～1×10^-6 mol/L Ang Ⅱ could markly induce the increase of PAI-1 antigen[（280±16） ng/ml vs （83±11） ng/ml,P〈0.05, 1×10^-6 mol/L] and activity [（10.35±1.47） U/ml vs （5.65±0.44） U/ml,P〈0.01,1 ×10^-6 mol/L] in a dosedependent manner compared to control; the increase of tPA antigen induced by Angll were less than the increase of PAI-1[A（31±6） ng/ml vs △（197±21） ng/ml,P〈0.01].Various concentration of Ang Ⅱ had seldom effect on tPA activity compareded with control [ （0.97±0.05） U/ml vs （0.95±0.08） U/ml,P〉0.05, 1×10^-6 mol/L]. When HUVECs were cultured with 1×10^-6 mol/L Ang Ⅱ for 0～24 h,PAI-1 antigen[（224±17） ng/ml vs （9.7±1.9） ng/ml,P〈0.01,24 h] and activity [（10.2±0.8） ng/ml vs （1.1±0.4） ng/ml,P〈0.01,24 h]were increased in a time dependent manner compared to control;tPA activity had no change [ （0.95±0.10）U/ml vs （1.00±0.04） U/ml,P〉0.05]. Conclusion Ang Ⅱ could stimulate the release of PAI-1 and tPA and increase the activity of PAI-1.The antigen of PAI-1 were much more than those of tPA. The activity oftPA had seldom any change by AngⅡ stimulating.