Japanese Thrombophilia : Diagnoses and Prevention

磷脂酰丝氨酸可显著加速凝血反应。在之前提交发表的一篇通讯中，我们利用因子xa -凝血酶原反应系统证明了磷脂酰胆碱、磷脂酰乙醇胺和溶血磷脂酰胆碱对凝血反应的影响，并讨论了膜磷脂的新功能。本研究通过研究磷脂对蛋白C/蛋白S反应的影响，探讨磷脂在凝血调节反应（抗凝系统）中的作用。我们建立了测定活化蛋白C活性和蛋白S活性的定量方法，并利用这些方法测定了加入不同磷脂组成的脂质体后的活性。我们发现磷脂酰胆碱以剂量依赖的方式抑制活化蛋白C和蛋白S的活性，如在因子xa -凝血酶原反应系统中。另一方面，磷脂酰乙醇胺和溶血磷脂酰胆碱对活化蛋白C活性没有影响。磷脂酰乙醇胺抑制因子-凝血酶原系统的凝血活性，溶血磷脂酰胆碱加速凝血活性，但在蛋白C/蛋白S反应系统中未观察到这种作用。凝血和抗凝反应被凝血酶巧妙地平衡，同时具有促凝剂和抗凝剂的作用。因此，磷脂酰乙醇胺和溶血磷脂酰胆碱在因子xa -凝血酶原和蛋白C/蛋白S反应体系中表现出不同的作用是可以理解的。凝血和抗凝反应似乎是由发生凝血反应的细胞膜磷脂组成的变化协调和控制的。

Phosphatidylserine is known to significantly accelerate the blood coagulation reaction. In a previous communication submitted for publication, we demonstrated that phosphatidylcholine, phosphatidylethanolamine and lysophosphatidylcholine showed effects on the blood coagulation reaction using the factor Xa-prothrombin reaction system, and discuss a new function of membrane phospholipids.The present study examined the role of phospholipids in the blood coagulation regulatory reaction (anticoagulation system), by studying the effects of phospholipids on the protein C/protein S reaction. We have established quantitative methods for measuring activated protein C activity and protein S activity, and used them to measure their activity after the addition of liposomes with different phospholipid compositions. We found that phosphatidylcholine inhibited activated protein C and protein S activities in a dose-dependent manner, as in the factor Xa-prothrombin reaction system. On the other hand, phosphatidylethanolamine and lysophosphatidylcholine showed no effect on activated protein C activity. Phosphatidylethanolamine inhibited and lysophosphatidylcholine accelerated coagulation activity in the factor Xa-prothrombin system, but such effects were not observed in the protein C/protein S reaction system. The coagulation and anticoagulation reactions are exquisitely balanced by thrombin, with a role both as a procoagulant and anticoagulant. Therefore, it is understandable that phosphatidylethanolamine and lysophosphatidylcholine show different effects in the factor Xa-prothrombin and protein C/protein S reaction systems. It appears that coagulation and anticoagulation reactions are co-ordinated and controlled by changes in phospholipid composition of the cellular membrane where the coagulation reaction takes place.