Effect of a purified diet on dystrophic cardiac calcinosis in mice.

Male and female C3H/HeNCrl mice were divided into test groups and fed either a purified diet (AIN-76A) or a natural ingredient diet (NIH-07). Lesions of dystrophic cardiac calcinosis (DCC) were found to be more prevalent and more severe in mice fed the purified diet. The cardiac changes, which were similar in nature in both groups of mice, consisted of randomly distributed foci of myocardial mineralization and fibrosis. These lesions were not associated with clinical disease or significant alterations in serum calcium, lactic dehydrogenase, aspartate aminotransferase, alkaline phosphatase or creatine kinase levels. We conclude that AIN-76A purified diet should be utilized with caution in toxicology studies which use mice as experimental subjects, especially if the heart is a potential target organ.