Identification of a reversible inhibitor of plasminogen activators in blood plasma

• Published in: FEBS letters 1985-10, Vol.190 (2), p.315-318
• Main Authors: Kluft, C., Jie, A.F.H., Sprengers, E.D., Verheijen, J.H.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Blood coagulation. Blood cells; DDAVP, desamino-D-arginine vasopressin; DFP, diisopropyl phosphofluoridate; Fundamental and applied biological sciences. Psychology; General aspects, investigation methods, hemostasis, fibrinolysis; Glycoproteins - blood; Hot Temperature; Humans; IgG, immunoglobulin G; Immunochemistry; Kinetics; Molecular and cellular biology; PA, plasminogen activator; plasma; plasminogen activator; Plasminogen Inactivators; Protein Binding; t-PA, tissue type plasminogen activator; Tissue Plasminogen Activator - antagonists & inhibitors; Tissue Plasminogen Activator - metabolism; tissues
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(85)81309-0

Inhibition of tissue-type plasminogen activator (t-PA) by pooled plasma could be ascribed for only 60% to the endothelial cell type PA inhibitor. The residual inhibition is ascribed to a so-far undescribed plasma component present at 0.2 nmol l . This component shows reversible binding to t-PA with an apparent K i of 10 pmol l (does not hinder t-PA binding to fibrin); also reacts with urokinase, but not with DIP-t-PA; is stable at 37°C and does not occur in media of endothelial cells, hepatocytes and fibroblasts. This PA binding component in plasma adds to the regulation of plasminogen activator activities. Fibrinolysis Tissue-type plasminogen activator Urokinase Blood plasma Endothelial cell type plasminogen activator inhibitor Protease inhibitor