QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Lammi-Keefe, C. J. Articles by Hegarty, P. V. J. Search for Related Content PubMed PubMed Citation Articles by Lammi-Keefe, C. J. Articles by Hegarty, P. V. J.

Effect of Level of Dietary Protein and Total or Partial Starvation on Catalase and Superoxide Dismutase Activity in Cardiac and Skeletal Muscles in Young Rats^1,2,

Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN 55108

In cells the level of potentially toxic superoxide radical (O₂^-) is controlled by superoxide dismutase (SOD); the level of hydrogen peroxide (H₂O₂), also potentially toxic, is controlled by catalase and glutathione peroxidase. To study the effects of altered food intake or dietary protein content on SOD and catalase in cardiac and skeletal muscles, young rats were fed ad libitum diets containing 3, 6 or 25% casein or were subjected to total or partial food restriction (resulting in similar body weight losses). Rats fed a diet containing 3 or 6% casein had much lower growth rates than those fed 25% casein, but the muscle catalase activities were similar in all three groups. Catalase activities in muscles of rats whose food intake was restricted were twice those in rats fed ad libitum. Rats fed ad libitum had higher muscle SOD activities at 41 days of age than did 25-day-old rats, irrespective of the amount of dietary protein or the rate of growth. Twenty-five-day-old rats whose food intake was totally restricted for 2 days had skeletal muscle SOD activities similar to the higher activities seen at 41 days of age in ad libitum-fed rats, but SOD activity in the heart was unchanged after food restriction. The responses of catalase and SOD in muscles differ from the responses reported for these enzymes in liver and erythrocytes when food intake or dietary protein is altered.

KEY WORDS: • dietary protein • starvation • muscles • catalase • superoxide dismutase

¹ This study was supported in part by the Science and Education Administration, U.S. Department of Agriculture (Grant No. 5901-0410-8-0014-0). Scientific Journal Series, Paper No. 13,822, Minnesota Agricultural Experiment Station.

² Presented in an abstract: Lammi-Keefe, C. J., Hegarty, P. V. J. & Swan, P. B. (1982) Effects of varying protein or food intake on catalase and superoxide dismutase activities in rat muscles. Proc. Nutr. Soc. 41, 40A.

³ Present address: Department of Nutritional Sciences, University of Connecticut, Storrs, CT 06268.

⁴ Present address: Department of Human Development and Consumer Sciences, University of Houston, Houston, TX 77004.

Manuscript received 11 January 1984.