PLATELET PLASMINOGEN-ACTIVATOR INHIBITOR-1 IN PATIENTS WITH TYPE-II DIABETES

OBJECTIVE - To compare platelet plasminogen activator inhibitor 1 (PAI-1) concentration in type II diabetic patients and healthy control subjects. RESEARCH DESIGN AND METHODS - We studied a group of 12 diabetic patients whose disease was controlled by diet or sulfonylurea therapy and a group of 17 nondiabetic control subjects. All subjects were free of clinically advanced vascular disease. PAI-1 antigen concentrations were measured in 5 X 10(8) isolated platelets, which were lysed by 1% Triton X-100. RESULTS - Mean platelet PAI-1 was significantly higher in diabetic patients (264 +/- 83 ng/5 X 10(8) platelets) compared with control subjects (202 +/- 71 ng/5 X 10(8) platelets) (P < 0.05). A significant independent positive correlation was found between platelet PAI-1 concentrations and fasting plasma specific insulin levels in the diabetic patients (r = 0.63, P = 0.03). CONCLUSIONS - These findings suggest that 1) a higher platelet PAI-1 concentration may contribute to enhanced thrombosis in type II diabetes and 2) megakaryocyte PAI-1 synthesis may be under the control oi insulin.