Anticoagulant properties of placenta protein 4 (annexin V).
A placenta protein, originally termed PP4, was found to inhibit the aPTT in a concentration-dependent manner. PP4 which turned out to be identical with a vascular anticoagulant of the annexin type, inhibits the blood clotting process by binding of the essential lipids in a reaction which is dependent on calcium ions. Also in the presence of calcium PP4 combines with platelet membranes neutralizing their procoagulant effect. By fluorescence-microscopy binding of PP4 to stimulated macrophages is shown. The antithrombotic effect of PP4 is demonstrated by means of thrombelastography of human blood. Coagulation triggered by the addition of thromboplastin/lipid-mixtures is extinguished by PP4.
Römisch
J
J
Research Laboratories of Behringwerke AG, Marburg, FRG.
Schorlemmer
U
U
Fickenscher
K
K
Pâques
E P
EP
Heimburger
N
N
D000925:Anticoagulants; D001777:Blood Coagulation / Q000502:physiology; D001792:Blood Platelets / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D008055:Lipids / Q000502:physiology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D010314:Partial Thromboplastin Time; D011257:Pregnancy Proteins / Q000502:physiology*; D011485:Protein Binding; D013916:Thrombelastography; D015054:Zymosan / Q000494:pharmacology
D000925:Anticoagulants; D008055:Lipids; D011257:Pregnancy Proteins; D015054:Zymosan