STUDIES ON PLASMA KALLIKREIN AND ITS RELATIONSHIP TO PLASMIN

• Published in: The Journal of pharmacology and experimental therapeutics Vol. 130; no. 4; pp. 484 - 491
• Main Authors: WEBSTER, M E, PIERCE, J V
• Format: Journal Article
• Language: English
• Published: United States American Society for Pharmacology and Experimental Therapeutics 01.12.1960
• Subjects: Fibrinolysin; Fibrinolysis - physiology; Humans; Kallikreins - blood; Old Medline; Plasma Kallikrein; KALLIKREIN/blood; FIBRINOLYSIS/physiology
• ISSN: 0022-3565; 1521-0103

The possibility that plasmin and plasma kallikrein (acetone-activated) are identical proteinases has been investigated. Although these proteinases are similar with respect to their inhibition by various inhibitors, differences in the ratio of their inhibition can be demonstrated. In addition, the separation of plasminogen by euglobulin precipitation divides kallikreinogen into two fractions. The kallikrein from these fractions when activated with acetone could not be distinguished by their reaction to inhibitors. It is unlikely that plasmin is involved in the acetone activation of plasma kallikrein. Streptokinase did cause the activation of small quantities of plasma kallikrein. However, acetone activation of plasma kallikrein was not inhibited with ovomucoid inhibitor nor was plasmin activated with acetone. Acetone probably caused the destruction of plasmin inhibitors, since streptokinase can activate plasminogen in plasma after acetone treatment. Plasmin is probably not the protease responsible for the destruction of kallidinogen when human plasma is stored at pH 8.0, 4°C for 4 days, since ovomucoid failed to inhibit this destruction. The addition of streptokinase to plasma also causes the destruction of kallidinogen, but this destruction is not due to either plasma kallikrein or plasmin, since it is not inhibitable with soybean trypsin inhibitor.