Aprotinin inhibits urokinase but not tissue-type plasminogen activator.
The protease inhibitor, aprotinin, has been examined for its ability to inhibit urokinase and tissue-type plasminogen activators at pH 7.4 in assays utilizing pyroGlu-Gly-Arg-p-nitroanilide and H-D-Ile-Pro-Arg-p-nitroanilide as substrates, respectively. Aprotinin inhibited both two-chain low molecular weight urokinase and the high molecular weight form of the enzyme in a competitive manner with a similar Ki (27 microM). There was no observable inhibition of tissue-type plasminogen activators at aprotinin concentrations up to 500 microM. These findings suggest that sensitivity to inhibition by aprotinin could be used to distinguish tissue-type and urokinase-type plasminogen activators.
Lottenberg
R
R
Department of Medicine, University of Florida College of Medicine, Gainesville 32610.
Sjak-Shie
N
N
Fazleabas
A T
AT
Roberts
R M
RM
D007611:Aprotinin / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D013053:Spectrophotometry; D010959:Tissue Plasminogen Activator / Q000037:antagonists & inhibitors*; D014568:Urokinase-Type Plasminogen Activator / Q000037:antagonists & inhibitors*
D007611:Aprotinin; D010959:Tissue Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator