Reexamination of the extent of the activation of Lys78 plasminogen by tissue plasminogen activator in the presence of polymerized fibrin

Haemostasis. 1996 Jul-Aug;26(4):220-7. doi: 10.1159/000217211.

Abstract

The rate of the conversion of Lys78 plasminogen (Lys78-plg) to Lys78 plasmin by tissue plasminogen activator (tPA) was directly quantitated by SDS-PAGE. The apparent second-order rate constant (Kapp) was (0.27 +/- 0.07) x 10(3)/M/s for single-chain tPA and Lys78-plg, and was enhanced approximately 5-fold by fibrinogen and 17-fold by polymerized fibrin. Kapp was (1.57 +/- 0.46) x 10(3)/M/s for two-chain tPA and Lys78-plg, and was enhanced approximately 2.6-fold by fibrinogen and 3.6-fold by fibrin. The factor of the enhancement by polymerized fibrin was far less than in previous reports in which chromogenic substrate was commonly employed.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biopolymers
  • Drug Synergism
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme Activation / drug effects
  • Fibrin / chemistry
  • Fibrin / pharmacology*
  • Fibrinolysin / biosynthesis
  • Humans
  • Kinetics
  • Plasminogen / metabolism*
  • Recombinant Proteins / pharmacology
  • Tissue Plasminogen Activator / pharmacology*

Substances

  • Biopolymers
  • Recombinant Proteins
  • lysyl(78) plasminogen
  • Fibrin
  • Plasminogen
  • Tissue Plasminogen Activator
  • Fibrinolysin