Effect of angiotensin convertase inhibitors on lipid peroxidation and peroxyl radical-trapping capacity in rats with experimental diabetes.

Effect of two angiotensin convertase inhibitors, enalapril and captopril, on blood plasma and erythrocyte lipid peroxidation and plasma peroxyl radical-trapping capacity was studied in rats with streptozotocin-induced diabetes. A progressive increase in blood erythrocyte malondialdehyde (MDA) level was observed in diabetic rats after 6 and 12 weeks. Blood plasma MDA level increased while plasma peroxyl radical-trapping capacity was decreased after 12 weeks. Captopril (2 mg/kg body weight) augmented the diabetes-induced changes in MDA content after 6 weeks and prevented them after 12 weeks increasing also the peroxyl radical-trapping capacity. Enalapril (1 mg/kg body weight) counteracted the diabetes-induced changes in MDA content after both 6 and 12 weeks but did not affect the plasma peroxyl radical-trapping capacity. These results suggest a possibility of a therapeutic use of angiotensin convertase inhibitors to attenuate the effects of oxidative stress in diabetes.