We have measured various fibrinolytic and coagulation parameters (t-PA antigen, PAI, fibrinogen, plasminogen and factor VII) before and after 10 min of venous occlusion in 20 hypertryglyceridaemic subjects (twelve males and eight females, age 38 +/- 4 years, body mass index 23 +/- 1.5) and 20 healthy normal subjects, matched for sex (twelve males and eight females), age (37 +/- 3.5 years) and body mass index (22.8 +/- 1.4). At rest, t-PA:Ag, PAI, fibrinogen, plasminogen and factor VII were significantly (P < 0.005) higher in hypertriglyceridaemic subjects than in normal controls. After venous occlusion, the increase in all parameters except t-PA:Ag was more marked in the patient group than in the controls. Only the percentage increase in t-PA:Ag was higher in normal controls (358.8%) than in hypertriglyceridaemic subjects (91.9%). There was a positive correlation between serum triglycerides levels and PAI at rest (r = 0.72, P < 0.01) and a negative correlation between serum triglycerides levels and t-PA antigen after venous occlusion (r = -0.45, P < 0.05) suggesting an impairment of fibrinolysis in hypertriglyceridaemia.