uPAR-mediated plasminogen activation on VSMCs. VSMCs in suspension were preincubated with pro-uPA and washed, and plasmin generation was determined after the addition of plasminogen (200 nmol/L) and H-;D-Val-Leu-Lys-AMC (0.2 mmol/L). Data are shown for plasmin generation assayed in the absence (▪) and presence (•) of 6AHA (1 mmol/L) as an antagonist of plasminogen binding and after preincubation of the cells with PI-PLC (▿) or the anti-uPAR MoAb R3 (▵). The inset shows a similar experiment performed with VSMC monolayers in a 24-well tissue culture plate. Data are shown in the absence (▪) and presence (•) of 6AHA.