Experimental evaluation of Enalapril on the antioxidant protection and nitrogen oxide system of the brain in rats with type 2 diabetes mellitus

Abstract

Abstract. Enalapril effect produced on the antioxidant protection and nitrogen oxide system in the brain of rats with experimental type 2 diabetes mellitus is examined. The experiments were conducted on nonlinear laboratory albino male rats with 0.18-0.20 kg of their body weight and type 2 diabetes mellitus simulated by streptozotocin and high-fat diet. Intensity of lipid peroxide oxidation was evaluated by the content of products reacting with 2-thiobarbituric acid. The state of the antioxidant protection system was evaluated by the activity of superoxide dismutase and catalase. To evaluate the state of NO-system in the cerebral cortex and hippocampus, the content of stable nitrogen monoxide metabolites was determined: nitrite-ions as well as activity of NO-synthase. Under conditions of damaged nervous system induced by type 2 diabetes mellitus the content of products reacting with 2- thiobarbituric acid in the cerebral cortex and hippocampus is found to increase and the activity of catalase and superoxide dismutase is found to decrease; the content of nitrite-ions and NO-synthase activity increases which is indicative of intensification of lipid peroxide oxidation processes and inhibition of the antioxidant protection and nitrogen oxide systems. Under effect of enalapril (14 days) rats with type 2 diabetes mellitus demonstrate the following in both examined structures of the brain: the content of products reacting with 2-thiobarbituric acid decreases, activity of catalase and superoxide dismutase increases in the cerebral cortex, the content of nitrite-ions in both examined structures of brain decreases, and activity of NO-synthase decreases in the hippocampus only. The obtained results are indicative of a correcting effect of enalapril on the prooxidant-antioxidant balance, and moreover, on the indices of NO system in the cerebral cortex and hippocampus of rats with nervous system damage, which evidences its available neuroprotective properties with central genesis complications due to type 2 diabetes mellitus.