Cytochrome oxidase and reductase in muscle from vitamin E-deficient rabbits

1. 1. One member of a pair of male litter mate New Zealand rabbits was placed on a vitamin E-deficient diet, and the other member was pair-fed the same diet supplemented with vitamin E. 2. 2. Cytochrome c reductase and oxidase enzyme determinations were carried out on biopsy material obtained at weekly intervals. 3. 3. Cytochrome c reductase was elevated in deficient animals in the terminal stages of deficiency. This elevation was apparent when the enzyme activity was expressed in units of activity per milligram of nondialyzable nitrogen, enzyme activity per milligram dry weight, or units of enzyme activity per milligram of wet weight. 4. 4. Cytochrome c oxidase tended to decrease in the first week and then returned to normal levels. 5. 5. These results strongly suggest that disruption of the cytochrome system may be a part of the biochemical metabolic defect in nutritional muscular dystrophy.