Chen H, Wu Y I, Hsieh Y L, Shi G Y, Jiang M J, Chang W C, Chuang W J, Kan W M, Tang M J, Jen C J
Department of Physiology, National Cheng-Kung University, Tainan, Taiwan, ROC.
Thromb Haemost. 1997 Aug;78(2):934-8.
To investigate whether the endothelium-platelet interactions may be altered by plasminogen activation, cultured human umbilical vein endothelial cells (ECs) were treated with tissue-type plasminogen activator (t-PA) in the presence of plasminogen, and platelet adhesion to ECs was subsequently measured by using a tapered flow chamber. Our results demonstrated that platelets adhered more readily to t-PA treated EC monolayer than to the control monolayer at all shear stress levels tested. This phenomenon was treatment time-dependent and dose-dependent, and it could be blocked by adding plasmin inhibitors, such as epsilon-amino caproic acid and aprotinin. Adherent platelets on t-PA treated EC monolayer underwent more severe shape change than those on the control monolayer. While the extracellular matrix directly treated with t-PA attracted less platelets than the control matrix did, platelet adhesion to the matrix that was produced by t-PA-treated ECs was unaltered. These data suggest that t-PA treatment on ECs compromised antiplatelet-adhesion capability on their apical surface without altering the reactivity of their extracellular matrix towards platelets.
为了研究纤溶酶原激活是否会改变内皮细胞与血小板之间的相互作用，在纤溶酶原存在的情况下，用组织型纤溶酶原激活剂（t-PA）处理培养的人脐静脉内皮细胞（ECs），随后使用锥形流动腔测量血小板与ECs的黏附情况。我们的结果表明，在所有测试的剪切应力水平下，血小板更容易黏附于经t-PA处理的EC单层，而不是对照单层。这种现象具有处理时间依赖性和剂量依赖性，并且可以通过添加纤溶酶抑制剂（如ε-氨基己酸和抑肽酶）来阻断。与对照单层相比，经t-PA处理的EC单层上黏附的血小板发生更严重的形状变化。虽然直接用t-PA处理的细胞外基质比对照基质吸引的血小板少，但血小板对经t-PA处理的ECs产生的基质的黏附没有改变。这些数据表明，对ECs进行t-PA处理会损害其顶端表面的抗血小板黏附能力，而不会改变其细胞外基质对血小板的反应性。
