The Inhibition of Tissue Activator and Urokinase by Human Plasma

Summary

Plasma reduced the activity of urokinase and, to a lesser extent, tissue activator on unheated fibrin plates. After depletion of plasminogen by lysine-Sepharose the inhibitory effect of plasma was increased.

Normal plasma separated on DEAE-Sepharose or, after passage through lysine-Sepharose, on Sephadex G-100 provided fractions in three regions capable of inhibiting tissue activator. The high molecular weight fractions inhibited both activators, but after plasma fractionation on Sephadex 4B the inhibitory activities against tissue activator and urokinase eluted separately. Urokinase inhibition eluted with a₂-macroglobulin: the inhibition of tissue activator was of higher molecular weight and of greater lability. Inhibition of tissue activator was found in two lower molecular weight regions: the fractions of one region inhibited tissue activator and coincided with the elution of fast-acting antiplasmin activity. The other region inhibited both tissue activator and urokinase. Alpha₁ antitrypsin and antithrombin III eluted after both inhibitory regions.

Key words

Urokinase - Tissue activator - Plasma inhibitors of fibrinolysis

• References

• 1 Rijken DC, Wijngaards G, Welbergen J. Relationship between tissue plasminogen activator and the activator in blood and vascular wall. Thromb Res 1980; 18: 815-830
• 2 Deutsch DG, Mertz ET. Plasminogen: purification from human plasma by affinity chromatography. Science 1970; 170: 1095-1096
• 3 Rickli EE, Zaugg H. Isolation and purification of highly enriched tissue plasminogen activator from pig heart. Thrombos Diathes Haemorrh 1970; 23: 64-76
• 4 Harpel P PC. Human plasma ±_2--macroglobulin: an inhibitor of plasma kallikrein. J Exp Med 1970; 132: 330-371
• 5 Beattie AG, Ogston D, Bennett NB, Douglas AS. Inhibitors of plasminogen activation in human blood. Br J Haematol 1976; 32: 135-143
• 6 Bennett NB. A method for the quantitative assay of inhibitor of plasminogen activation in human serum. Thrombos Diathes Haemorrh 1967; 17: 12-22
• 7 Mancini G, Carbonara AO, Heremans JF. Immunochemical quantitation of antigens by single radial immunodiffusion. Int J Immunochem 1965; 2: 235-238
• 8 Brakman P, Astrup T. Selective inhibition in human pregnancy blood of urokinase induced fibrinolysis. Scand J Clin Lab Invest 1963; 15: 603-609
• 9 Thorsen S. The inhibition of tissue plasminogen activator and urokinase-induced fibrinolysis by some natural proteinase inhibitors and by plasma and serum from normal and pregnant subjects. Scand J clin Lab Invest 1973; 31: 51-59
• 10 Hedner U, Nilsson IM, Jacobsen CD. Demonstration of low content of fibrinolytic inhibitors in individuals with high fibrinolytic capacity. Scand J Clin Lab Invest 1970; 25: 329-336
• 11 Aoki N, von Kaulla KN. Human serum plasminogen antiactivator: its distinction from antiplasmin. Am J Physiol 1971; 220: 1137-1145
• 12 Hedner U. Studies on an inhibitor of plasminogen activation in human serum. Thrombos Diathes Haemorrh 1973; 30: 414-424
• 13 Hedner U, Martinsson G. Inhibition of activated Hageman factor by an inhibitor of the plasminogen activation. Thromb Res 1978; 12: 1015-1023
• 14 Seigel-Ralston A, Astrup T. A previously undescribed fibrinolysis inhibitor in human blood. Nature 1972; 234: 180-181
• 15 Lijnen HR, Hoylaerts M, Collen D. Isolation and characterization of a human plasma protein with affinity for the lysine binding sites in plasminogen. J Biol Chem 1980; 255: 10214-10222
• 16 Ogston D, Bennett B, Herbert RJ, Douglas AS. The inhibition of urokinase by ±₂-macroglobulin. Clin Sci 1973; 44: 73-79
• 17 Clemmensen I, Christensen U. Inhibition of urokinase by complex formation with human ±₁-antitrypsin. Biochim Biophys Acta 1976; 249: 591-599
• 18 Clemmensen I. Inhibition of urokinase by complex formation with human antithrombin III in absence and presence of heparin. Thromb Haemostas 1978; 39: 616-623
• 19 Crawford GPM, Ogston D. The influence of α₁-antitrypsin on plasmin, urokinase and Hageman factor co-factor. Biochim Biophys Acta 1974; 354: 107-113
• 20 Crawford GPM, Ogston D. The action of antithrombin III on plasmin and activators of plasminogen. Biochim Biophys Acta 1975; 391: 189-192
• 21 Moroi M, Aoki N. The mechanism of reaction between α₂-plasmin inhibitor (α₂-antiplasmin) and enzymes. In: Collen D, Wiman B, Verstraete M. (Eds) The Physiological Inhibitors of Blood Coagulation and Fibrinolysis. 121-129 Elsevier Biomedical Press; Holland: 1979