Abstract
Twenty-four female rats consisting of 6 sets of litters were used for the experiment. After weaning, rats were divided into 4 groups and fed with 10, 18, 27 and 36% casein diet. Effect of protein nutrition on aging was examined from the anthropometric and biochemical viewpoint. The difference of growth in body weight, and that of the urinary excretion of creatinine and 17-ketosteroids observed in the early period of growing disappeared by the end of growth period. From 1 year after birth, serum alkaline phosphatase activity and serum cholesterol were also measured. However, effect of protein nutrition on these parameters was not clear due to the scatter of data. The difference in diet did not affect life span in the present experiments, but the effect of the variance of litters on it seemed to be significant between the rats fed 18% casein diet and those fed 10% casein diet. Rats fed high-protein diet had a great number of lesions in the kidney and hypophysis, and often an incidence of tumors.
