Effect of Chloride and Other Ions on the Activation of Bovine Plasminogen (Profibrinolysin)

Abstract

Sodium chloride inhibits the activation of crude plasminogen (profibrinolysin) by streptokinase and human globulin, or urokinase. The plasmin yield obtained in the presence of sodium chloride is increased by the use of increased activator (streptokinase + human globulin) concentrations. Anions other than chloride ion produce smaller and varying amounts of inhibition. Calcium ions have either a stabilizing or activating effect. In the absence of salt, bovine plasminogen activates spontaneously. During chloroform-activation the time to the onset of activation is related to the concentration of salt present. Purified human plasminogen does not appear to be susceptible to sodium chloride inhibition.