Effects of Thrombin on Factor VIII Activity: Stabilization of Factor VIII by Glycine Ethyl Ester

Summary

The action of purified thrombin on a preparation of antihemophilic factor with fibrinogen has been studied. In the absence of active thrombin (thrombin inactivated with DFP) polymerization of fibrin by calcium was accompanied by significant losses of AHF. In the presence of thrombin and calcium, 0.3 M glycine ethyl ester resulted in a significant reduction in the loss of AHF activity.

^* Present Address: Department of Pediatrics, Cincinnati Childrens Hospital, Cincinnati, Ohio.

• References

• 1 Rapaport S. I, Schiffman S, Patch M. J, Arnes S. B. The importance of activation of antihemophilic globulin and proaccelerin by traces of thrombin in the generation of intrinsic prothrombase activity. Blood 21: 221 1963;
• 2 Macfariane R. G, Biggs R, Ash B. J, Denson W. E. Interaction of Factors VIII and IX. Brit. J. Haemat 10: 530 1964;
• 3 Penick G. D. Some factors that influence utilization of antihemophilic activity during clotting. Proc. Soc. exp. Biol. (N. Y.) 96: 277 1957;
• 4 Alexander B, Goldstein R, Rich L, Le Bolloch A.G, Diamond L.K, Borges W. Congenital Afibrinogenemia. A study of some basic aspects of coagulation. Blood 9: 843 1954;
• 5 Miller D, Van Vunakis H. The effect of diisopropyl fluorophosphate on the proteinase and esterase activities of thrombin and on prothrombin and its activators. J. biol. Chem 223: 227 1956;
• 6 Kekwick R. A, Walton P. L. Conditions influencing the stability of human antihemophilic factor. Nature (Lond.) 194: 878 1962;
• 7 Abildgaard V. Acceleration of fibrin polymerization by acetate and other low molecular ions. Scand. J. clin. Lab. Invest 16: 521 1964;
• 8 Lorand L, Jacobsen A. Specific inhibitors and the chemistry of fibrin polymerization. Biochemistry 3: 1939 1964;
• 9 Pool J. G, Robinson J. Assay of plasma antihemophilic globulin. Brit. J. Haemat 5: 17 1959;
• 10 Mosesson M. W. Preparation of human fibrinogen free of plasminogen. Biochim. biophys. Acta (Amst.) 57: 204 1962;
• 11 Biggs R, Macfariane R. G. The reaction between Factors VIII and IX to form a Factor X activator. Thrombos. Diathes. haemorrh. (Stuttg.) Suppl 17: 23 1965;
• 12 Barrow E. M, Amos S. M, Heindel G, Graham J. B. Separation of the antihemophilic factor (F. VIII) from fibrinogen with thrombin and manganese chloride. Proc. Soc. exp. Biol. (N Y.) 121: 1001 1966;