Robert E. Burch

The effect of aging on trace element content of various rat tissues: I. Early stages of aging

The total protein and trace element content in various tissues from 1, 2, 4, 8, 16, 32, 64, and 128 day-old rats were determined. Protein content in heart, skin and hair continued to increase as a function of age whereas liver, kidney and lung protein content showed no change after the weaning period. The protein content in all tissues tested decreased sharply to minimum values at 2 to 4 days of age before increasing to constant levels.The trace element content of tissues tested fluctuated prior to weaning. This fluctuation was parallel to changes in milk copper and zinc levels from lactating rats. The concentration of most trace elements in the various tissues leveled off to steady values after weaning. Among the various trace elements studied, selenium and manganese content had the most profound increase as a function of age in liver and kidney.