Antioxidant enzymes in mammals naturally adapted to oxygen deficiency

The activity of the key antioxidant enzymes, superoxide dismutase (SOD) and catalase, were studied in the liver, kidneys and heart of 8 mammalian species from 2 Orders – Insectivora and Rodentia. Some species-specific differences were found – the activities of the enzymes in the organs considerably differed even in the taxonomically close species. The specific profile of antioxidant enzymes in the organism of birch mouse appears to be due to the occurance of hibernation in this animal. In the heart of semi-aquatic Eurasian water shrew and European water vole, an increase of the catalase activity was noted. The activity of SOD and catalase in the same organ can differ significantly even in taxonomically close species of studied mammals, and it was caused, first of all, by the specificity of their ecological features and adaptation to hypoxia.