Enhancement of plasminogen activation and hydrolysis of purified fibrinogen and fibrin by dextran 70.

Abstract

Dextran 70 significantly enhanced the rate of activation of plasminogen into plasmin by urokinase as evidenced by increments in amidolytic activity using substrate S-2251. Dextran 70 did not enhance the amidolytic activity of preformed plasmin or urokinase. The combined use of gel permeation chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) clearly demonstrated enhancement of purified fibrinogen and fibrin degradation by dextran. High molecular weight soluble fibrin complexes readily demonstrable in early digest mixtures of normal fibrin were virtually absent in digest mixtures of fibrin containing dextran. In addition, digest mixtures of fibrinogen or fibrin with dextran contained a significantly lower proportion of fragment X than did digest mixtures without dextran. In contrast, fibrinolysis and fibrinogenolysis induced by preformed plasmin was not influenced by dextran. Steric exclusion effects may explain these findings.