Effects of phosphoethanolamine and phosphoserine on blood coagulation mechanism

¹ Coagulation Laboratory, Department of Surgery, Presbyterian-St. Luke's Hospital, Chicago, Illinois

Phosphoethanolamine and phosphoserine were studied for their in vitro effects on various phases of the blood coagulation mechanism. When added to freshly drawn, normal human blood both substances exhibit marked anticoagulant characteristics. When added to normal human plasma in the presence of either brain extract thromboplastin or Russell viper venom they produce an inhibition of clot formation which becomes more pronounced with increasing concentration. The effects observed appear to be due to an interference with thrombin formation rather than to an inhibition of the thrombin fibrinogen reaction. Evidence has been obtained which suggests that, depending upon their concentration, phosphoethanolamine and phosphoserine may inhibit either the formation of a prothrombin-converting principle only or inhibit, in addition, the activity of this principle as well.