Inactivation of Human Serum Plasminogen Antiactivator by Synthetic Fibrinolysis Inducers^[*]

Summary

Human serum plasminogen antiactivator was separated from serum antiplasmin by isoelectric precipitation and ammonium sulfate fractionation followed by Sephadex chromatography. With the use of human vascular activator it was demonstrated that the serum antiactivator is functionally distinct from serum antiplasmin. Both antiplasmin and antiactivator were irreversibly inactivated when incubated with synthetic fibrinolysis inducing compounds, this inactivation being independent from plasminogen activation. Minor structural modifications of the compounds which abolished the fibrinolytic activity also abolished their effects on serum antiactivator. It is suggested that the pathway of the compound-induced fibrinolysis is an unbalancing of the activator-antiactivator system by inactivating antiactivator, thus freeing the activator for plasminogen activation.

^* Supported by grants from the American Heart Association, Belle Bonfils Memorial Blood Bank, Denver, and National Heart Institute USPHS (HE 9985).

• References

• 1 von Kaulla K. N, Ens G. On structure-related properties of synthetic organic clot-dissolving (thrombolytic) compounds. Biochem. Pharmac. 16: 1023 1967;
• 2 von Kaulla K. N. Inactivation of antiplasmin and complement C’ in human plasma rendered fibrinolytic by synthetic organic compounds. Thrombos. Diathes. haemorrh. (Stuttg.) 10: 151 1963;
• 3 von Kaulla K. N. Structure-dependent fibrinolytic (clot-dissolving) activity of antiinflammatory drugs and related compounds. Arzneim.-Forsch. (Drug Res.) 18: 407 1968;
• 4 Aoki N, von Kaulla K. N. β₁C-globulin and synthetic fibrinolytic agents. Proc. Soc. exp. Biol. (N.Y.) 130: 101 1969;
• 5 Michaelis L. Der Azetat-Veronal-Puffer. Biochem. Z. 234: 139 1931;
• 6 Eggstein M, Kreutz F. H. Vergleichende Untersuchungen zur quantitativen Eiweiß-bestimmung im Liquor und eiweißarmen Lösungen. Klin. Wschr. 33: 879 1955;
• 7 Lowry O. H, Rosebrough N. J, Farr A. L, Randall R. J. Protein measurement with the Folin phenol reagent. J. biol. Chem. 193: 265 1951;
• 8 Aoki N, von Kaidla K. N. The procoagulant in human urine: Purification, assay and some biochemical and physiological properties. Thrombos. Diathes. haemorrh. (Stuttg.) 16: 586 1966;
• 9 Ouchterlony O. Diffusion in gel methods for immunological analysis. II. In: Progress in Allergy. ed. Kallós P, Waksman B. H. vol. 6 30. Karger; Basel: 1962
• 10 von Kaidla K. N, Schiätz R. L. Methods for evaluation of human fibrinolysis: Studies with two combined techniques. Amer. J. clin. Path. 29: 104 1958;
• 11 Schultze H. E, Heimburger N, Heide K, Haupt H, Störiko K, Schwick H. G. Preparation and characterization of α₁-trypsin inhibitor and α₂-plasmin inhibitor of human serum. Proc. 9th Congr. European Soc. Haematol., Lisbon 1963, p. 1315.
• 12 Mann R. D, Cotton S, Jackson D. Antiplasmin activity of electrophoretically separated human serum fractions. J. clin. Path. 19: 185 1966;
• 13 Ganrot P. O. Inhibition of plasmin activity by α₂-macroglobulin. Clin. chim. Acta 16: 328 1967;
• 14 Riding I. M, Ellis D. Antiplasmin activity of β-lipoprotein. J. atheroscler. Res. 4: 189 1964;
• 15 Skrzydlewski Z, Niewiarowski S, Skrzydlewska J. Inhibition of proteolytic enzymes by β-lipoprotein. J. atheroscler. Res. 6: 273 1966;
• 16 Kucinski C. S, Fletcher A. P, Sherry S. Effect of urokinase antiserum on plasminogen activators : Demonstration of immunologic dissimilarity between plasma plasminogen activator and urokinase. J. clin. Inv. 47: 1238 1968;
• 17 Warren B. A. Fibrinolytic activity of vascular endothelium. Brit. med. Bull. 20: 213 1964;
• 18 Celander D. R, Celander E. Characterization of fibrinolytic activity of vascular intima. Amer. J. Physiol. 211: 319 1966;
• 19 Worowski K, Niewiarowski S, Skrzydlewski Z, Farbiszewski R. Inhibitory effect of human serum beta-lipoprotein on plasmin, trypsin, alpha-chymotrypsin and thrombin. Bull. Acad, poi. Sci. Ser. Sci.-Biol. 15: 733 1967;