血管紧张素Ⅱ和卡托普利、缬沙坦对人脐静脉内皮细胞PAI-1、tPA蛋白表达的影响

Effects of Angiotensin Ⅱ and Captopril, Valsartan 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）和血管紧张素转换酶抑制剂（ACEI），卡托普利和AngⅡ1型受体（AT-1）拮抗剂缬沙坦对人脐静脉内皮细胞（HUVECs）1型纤溶酶原激活物抑制剂（PAH）、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（10^-6～10^-9mol／L）与HUVECs共同孵育24h，以及将10^-6mol／L的AngⅡ与HUVECs作用不同时间（0、4、8、12、24h）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，并观察卡托普利和缬沙坦干预后的影响。结果 10^-6mol／LAngⅡ作用HUVECs 24h后，可使细胞分泌的PAI-1含量与对照组相比明显增高（280±15．60 vs 83．33±10．56）ng／mL，P〈0．01），PAI-1活性明显增加（9．25±0．39 vs 7．53±0．33）Iu／mL，P〈0．01），AngⅡ虽也可刺激tPA含量增加（101．67±3．78 vs 70±5．62）ng／mL，（P〈0．01），但PAI-1的增量是tPA增量的6～7倍（Δ196．67±21．34 vs Δ31±6．50）ng／mL，（P〈0．01），AngⅡ对tPA活性无影响（0．97±0．05 vs 0．95±0．08）ng／mL，（P〉0．05）；缬沙坦可显著抑制AngⅡ的促PAI-1分泌作用（212．67±5．38 vs 290±6．57）IU／mL，（P〈0．01），而卡托普利对Ang1／的促PAI-1分泌作用无明显抑制作用（278．33Ⅱ9．16 vs 290±6．57）IU／mL，（P〉0．05）。结论 AngⅡ可促使HUVECs分泌PAI-1，并使其活性增加；AngⅡ亦可刺激tPA分泌，但作用弱于PAI-1，对其活性无明显影响。缬沙坦可抑制AngⅡ促HUVECs分泌PAI-1的作用；卡托普利的作用不显著。

Objective To observe the effects of angiotensin Ⅱ （Ang Ⅱ }, angiotensin converting enzyrne inhibitor （ACEI） captopril, and a specific type 1 angiotensin Ⅱ receptor （AT-1） antagonist valsartan on plasminogen activator inhibitor-1 （PAI-1） and tissue type plasminogen activator （tPA） in cultured human umbilical vein endothelial cells （HUVECs）. Methods Cultured HUVECs were incubated with Ang Ⅱ of 10^-6-10^-0mol/L for 24 hours. Captopril and valsartan were added respectively to the culture medium with or without Ang Ⅱ. Antigens and activities of PAI-land tPA in the cultured medium were measured by enzyme linked immunosorbent assay （ELISA） and the indirect chromogenic assay. Results Compared to control, 10^-9-10^6mol/L AngⅡ markedly increases PAI-1 antigen （ 280 ±15. 60 vs 83.33±10.56）ng/mL, （ P〈0. 05） and activities （9.25±0. 39 vs 7. 53±0.33 ）IU/mL, （ P〈0. 01, ） in a dose dependent and time dependent manner while no changes in tPA activities were found. Valsartan inhibited the increase of PAI-1 induced by Ang Ⅱ （212.67±5.38 vs 290±6.57）ng/mL, （P〈0.01） . Conclusion Ang Ⅱ stimulated the release of PAI-1 and tPA, but the increments of PAI-1 were much more than those of tPA. The activities of tPA were not increased by Ang Ⅱ. Valsartan inhibited the effects of Ang Hinduced release of PAI-1. Our findings suggest that Ang Ⅱ enhanced thrombosis by decreasing fibrinolytic activity.