UROKINASE PLASMINOGEN ACTIVATOR SYSTEM IN HUMANS WITH STABLE CORONARY ARTERY DISEASE

1. The present study compares plasma urokinase plasminogen activator (uPA) peptide levels, plasma plasminogen inhibitor (PAI‐1) activity and urokinase receptors (uPAR) on peripheral blood monocytes of patients with stable coronary artery disease (SCAD) and healthy volunteers. 2. Urokinase plasminogen activator levels were analysed by ELISA and PAI‐1 activity was determined by a plasmin generation method using the chromogenic substrate S2390. Relative uPAR numbers and the adhesion molecules CD11b/CD18 on peripheral blood monocytes were estimated using specific antibodies and flow cytometry. 3. Patients with SCAD were found to have higher plasma uPA peptide levels than age‐matched healthy subjects (10.40±0.99 vs 8.25±0.53 pmol/L, respectively; P < 0.05). 4. Plasma PAI‐1 activity was also higher in patients with SCAD than in healthy subjects (13.6±2.5 vs 5.2±1.0 IU/mL, respectively; P < 0.05). 5. Relative uPAR and CD11b/CD18 adhesion molecules were similar on peripheral blood monocytes of patients with SCAD and in healthy subjects. 6. The data indicate a pattern of expression/activity of uPA and PAI‐1 in patients with SCAD suggestive of an impaired fibrinolytic ability.