GGACK is an inhibitor of urokinase-type plasminogenactivator (uPA) and factor Xa (Kis = 1.8 and 8.7 μM, respectively).1,2 1.Kettner, C., and Shaw, E.The susceptibility of urokinase to affinity labeling by peptides of arginine chloromethyl ketoneBiochim. Biophys. Acta569(1)31-40(1979) 2.Kettner, C., and Shaw, E.The selective affinity labeling of factor Xa by peptides of arginine chloromethyl ketoneThromb. Res.22(5-6)645-652(1981)
THR-18 is an 18-mer peptide derived from the sequence of human plasminogenactivatorinhibitor 1 (PAI-1), having the ability to bind to a site of tissue plasminogenactivator (tPA) distal to its catalytic site and uncouple the beneficial clot-dissolving properties of tPA from its deleterious non-fibrinolytic effects.