摘要
目的 研究一些凝血和纤溶因子对尿激酶型纤溶酶原激活剂 (u PA)诱发纤溶反应的调节作用及机制。 方法 采用凝块溶解测定和纤维蛋白检测板测定观察了一些凝血和纤溶因子对 u PA诱导的纤溶反应的影响及相互作用。 结果 凝血酶激活的纤溶抑制因子 (TAFI)对 u PA或单链 u PA(scu PA)诱发的纤溶反应具有明显的拮抗作用 ,凝血酶调节因子 (TM)可明显增强其抑制作用。凝血酶对 u PA诱导的纤溶反应没有明显的影响 ,但可抑制 scu PA诱导的纤溶反应 ,该作用亦可被TM所增强或被水蛭素所消除。 结论 凝血酶 / TM可通过激活 TAFI对 u PA或 scu PA诱导的纤溶反应产生抑制作用 ,凝血酶对 scu PA诱发的纤溶反应的抑制作用亦可通过其对 scu PA的裂解失活而实现。
Objective To study the roles of fibrinolytic regulators in fibrinolysis induced by urokinase type plasminogen activator (uPA) and underlying mechanisms. Methods Clot lysis assay and fibrin detector plate were used for determining the effects of the regulators, including carboxypeptidase inhibitor (cPI), thrombin, thrombomodulin (TM) and hirudin, on the fibrinolysis induced by uPA or single chain uPA (scuPA). Results With clot lysis assay, uPA (2 nmol/L) or scuPA (6 nmol/L) gave no clot lysis in the absence of cPI, but they induced significant fibrinolysis in the presence of cPI (6 nmol/L), a specific inhibitor of thrombin activatable fibrinolysis inhibitor (TAFI), and again the uPA induced fibrinolysis was inhibited with the addition of TM (1 nmol/L or 10 nmol/L). Exogenous thrombin (3.8 nmol/L) did not influence uPA induced fibrinolysis, but it inhibited scuPA induced fibrinolysis. In fibrin detector plate, uPA and scuPA showed the same fibrinolytic activities in the absence of added thrombin and scuPA but not uPA was inactivated with the addition of thrombin (0.2 nmol/L), and the inactivation of scuPA was enhanced by TM (1 nmol/L), a stimulator of thrombin, or abolished by hirudin (285 nmol/L), a inhibitor of thrombin. Conclusion uPA or scuPA induced fibrinolysis is inhibited as a result of activation of TAFI by thrombin/TM and scuPA induced fibrinolysis may also be inhibited as a result of inactivation of scuPA via cleavage by thrombin.
出处
《空军总医院学报》
2003年第1期1-5,共5页
Journal of General Hospital of Air Force,PLA
关键词
尿激酶型纤溶酶原激活剂
纤溶反应
调节因子
Fibrinolysis
Thrombin
Plasminogen activators
Plasminogen activator inhibitor
