Preliminary data suggest that plasma concentration of plasminogen activators inhibitor type 1 (PAI-1) is genetically determined and may be related to differential regulation of plasma PAI-1 concentration at baseline and after stimulation...In conclusion, the rebound effect in serum PAI-1 concentration observed after streptokinase treatment may be related to the 4G/5G polymorphism in the PAI-1 gene promoter