Plasminogen activation by a tissue activator and effector properties of fibrinogen-N-terminal disulfide (N-DSK) fibrin complex

• Published in: Ukrainskij biohimičeskij žurnal Vol. 63; no. 3; p. 17
• Main Authors: Makogonenko, E M, Druzhina, N N, Lugovskoĭ, E V, Kolesnik, L A, Kudinov, S A
• Format: Journal Article
• Language: Russian
• Published: Ukraine 01.05.1991
• Subjects: Disulfides - chemistry; Electrophoresis, Polyacrylamide Gel; Fibrin - metabolism; Fibrinogen - metabolism; Humans; Kinetics; Plasminogen - metabolism; Tissue Plasminogen Activator - pharmacology
• ISSN: 0201-8470

Fibrinogen-NDSK complex is a model of protofibril having some features of the fibrin polymer structure. This complex has been studied for its ability to stimulate the plasminogen activation by t-PA. The fibrinogen-NDSK complex have increased the rate of plasminogen activation by t-PA as compared to fibrinogen or NDSK taken separately. This acceleration had slow and fast phases. Lys-plasminogen was activated more effectively as compared to glu-plasminogen. The kinetic parameters of glu- and lys-plasminogen activation at fast phase were: Km--0.18 and 0.015 mu/M, Kkat--0.27 and 0.06 s-1, respectively. Fibrinogen X2--fragments, deprived of alpha C-domains and NH2-end peptides of bB-chains, formed complexes with NDSK, which however did not stimulate the plasminogen activation by t-PA. These findings have shown that the fibrinogen-NDSK complex is an effective stimulator of the plasminogen activation by t-PA. The activating ability of the complex may be due to structures formed in the course of fibrinogen and NDSK polymerization as a result of alpha C-domain interaction.