Peyrou V, Lormeau J C, Hérault J P, Gaich C, Pfliegger A M, Herbert J M
Haemobiology Research Department, Sanofi Recherche, Toulouse, France.
Thromb Haemost. 1999 Mar;81(3):400-6.
Thrombin generation (TG) initiated by diluted tissue-factor was investigated in whole human blood, in platelet-rich plasma (PRP), in platelet-poor plasma (PPP), and in PPP supplemented with red blood cells (RBCs). TG was characterized by the lag time preceding the thrombin burst and by the endogenous thrombin potential (ETP). RBCs at normal haematocrit were found to influence the lag time to the same extent as platelets. When TG was carried out in PRP or in PPP + RBCs, both the ETP and lag time were dependent on the platelet count or on the haematocrit, but the shapes of the dose-response curves were different. The inhibition of TG in PPP+ RBCs by two direct thrombin and factor Xa inhibitors: hirudin and DX 9065A, and two antithrombin III (AT)-dependent anticoagulants: heparin and SR 90107A was found to be similar to that previously described in PPP and in PRP: hirudin and DX 9065A only delayed TG whereas heparin and SR 90107A both delayed and decreased TG. FACscan analysis following labelling with FITC-annexin V or with phycoerythrin-labelled antiglycophorin A of samples taken in the course of TG initiated in PPP + RBCs showed that no significant haemolysis occurred and revealed that 0.51+/-0.075% (mean +/- sem, n = 3) of RBCs steadily exposed procoagulant phospholipids on their outer surface throughout the TG course. Furthermore, incubation of factors Xa and Va with washed RBCs sampled during TG in PPP +RBCs resulted in a significant and constant prothrombinase activity. Taken together, these data show for the first time that normal RBCs may participate in the haemostatic process through exposure of procoagulant phospholipids.
在全血、富血小板血浆（PRP）、贫血小板血浆（PPP）以及补充了红细胞（RBC）的PPP中，研究了由稀释组织因子引发的凝血酶生成（TG）。TG的特征在于凝血酶爆发前的延迟时间和内源性凝血酶潜力（ETP）。发现正常血细胞比容的RBC对延迟时间的影响程度与血小板相同。当在PRP或PPP + RBC中进行TG时，ETP和延迟时间均取决于血小板计数或血细胞比容，但剂量反应曲线的形状不同。发现两种直接凝血酶和因子Xa抑制剂水蛭素和DX 9065A以及两种抗凝血酶III（AT）依赖性抗凝剂肝素和SR 90107A对PPP + RBC中TG的抑制作用与先前在PPP和PRP中描述的相似：水蛭素和DX 9065A仅延迟TG，而肝素和SR 90107A既延迟又降低TG。在用FITC-膜联蛋白V或藻红蛋白标记的抗血型糖蛋白A标记PPP + RBC中启动的TG过程中采集的样品后进行的FACscan分析表明，未发生明显溶血，并显示在整个TG过程中，0.51±0.075%（平均值±标准误，n = 3）的RBC在其外表面稳定地暴露促凝磷脂。此外，在TG期间从PPP + RBC中采集的洗涤RBC与因子Xa和Va一起孵育会产生显著且持续的凝血酶原酶活性。综上所述，这些数据首次表明正常RBC可能通过暴露促凝磷脂参与止血过程。
