Low-Affinity Heparin Stimulates the Inactivation of Plasminogen Activator Inhibitor-l by Thrombin
نویسنده
چکیده
The influence of heparin on the reaction between thrombin and plasminogen activator inhibitor-l (PAI-1) has been examined. With a 50-fold excess of PAI-1, the rate constant for the inhibition of thrombin was 458 mol/L"s", which increased to 5,000 mol/L"s" in the presence of 25 pg/mL unfractionated heparin or heparin with low affinity for antithrombin. The effect of low affinity heparin was then examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, using close to equimolar concentrations of reactants. Thrombin and PAI-1 formed a stable stoichiometric complex in the absence of heparin, which did not dissociate after the addition of 25 pg/mL low-affinity heparin. In contrast, when low-affinity heparin was added at the beginning of the reaction, there was an initial increase in PAI-1thrombin complex formation, but this was rapidly followed
منابع مشابه
Low-affinity heparin stimulates the inactivation of plasminogen activator inhibitor-1 by thrombin.
The influence of heparin on the reaction between thrombin and plasminogen activator inhibitor-1 (PAI-1) has been examined. With a 50-fold excess of PAI-1, the rate constant for the inhibition of thrombin was 458 mol/L-1s-1, which increased to 5,000 mol/L-1s-1 in the presence of 25 micrograms/mL unfractionated heparin or heparin with low affinity for antithrombin. The effect of low affinity hepa...
متن کاملLow-Affinity Heparin Stimulates the Inactivation of Plasminogen Activator Inhibitor-l by Thrombin
The influence of heparin on the reaction between thrombin and plasminogen activator inhibitor-l (PAI-1) has been examined. With a 50-fold excess of PAI-1, the rate constant for the inhibition of thrombin was 458 mol/L"s", which increased to 5,000 mol/L"s" in the presence of 25 pg/mL unfractionated heparin or heparin with low affinity for antithrombin. The effect of low affinity heparin was then...
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