CHANGES IN ANTIOXIDANT ENZYME-ACTIVITIES FOLLOWING THROMBOLYTIC THERAPY IN ACUTE MYOCARDIAL-INFARCTION

The aim of this study was to determine whether oxidative stress occurs in patients that received thromboyltic therapy. In 16 patients with a cute myocardial infarction, erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) activities (GSH) levels were measured before and 5 min, 1 h and 24 h after streptokinase infusion. The same parameters were studied upon admission, after the chest pain declined, 1 h and 24 h later in seven patients with acute myocardial infarction . In the treatment group, SOD activity and GSH level were significantl y decreased during the first 24 h after an attack (mean SOD activities were 2,889, 2,566, 2,606, 2,485 U/g Hb, the mean GSH levels were 64.3 6, 56.41, 54.28, 55.88 mg dL(-1) erythrocyte, respectively). GSHPx act ivities were not changed after the thrombolytic therapy. SOD, GSHPx an d GSH levels were not significantly altered in untreated patients duri ng the observation period. Our findings suggest that in acute myocardi al infarction, thrombolytic therapy significantly decreased erythrocyt e SOD activity and GSH level, possibly due to the generation of reacti ve oxygen species.