Possible involvement of free radicals and antioxidants in the early stages of the development of cardiomyopathy in BIO 14.6 Syrian Hamster.

The BIO 14.6 cardiomyopathic Syrian hamster is a well-known animal model of congestive cardiomyopathy. To evaluate the role of free radicals and antioxidant protection in the pathogenesis of cardiomyopathy in this animal, we studied the concentration of heart mitochondrial free radicals, the activities of glutathione peroxidase (GSHPx) and superoxide dismutase (SOD), and the effect of alpha-tocopherol on the early stage of myocardial damage (up to 90 days). The GSHPx activity in BIO 14.6 hamsters was found to be twice that in the normal control hamsters at 30 days of age, while SOD activity was unchanged at 30 and 90 days of age. The concentrations of mitochondrial free radicals in BIO 14.6 hamsters at 40 and 90 days of age were significantly higher than those in the normal control hamsters. A protective effect of alpha-tocopherol therapy was shown in BIO 14.6 hamsters treated during the early stage of cardiomyopathy (up to 90 days). These results show the role of free radicals and antioxidant protection in the pathogenesis of hamster cardiomyopathy. We suspect that an increase in the GSHPx activity in BIO 14.6 hamsters may be due to a compensatory mechanism to counteract oxidative stress, but antioxidant reserve was not sufficient to protect the heart from the toxic effects of increased free radicals in the early stage of cardiomyopathy.