Effects of dietary sulfur-containing amino acids on tissue levels of copper, ascorbic acid and α-tocopherol in rats

Abstract

We previously reported that addition of 5% L-cystine to 10% casein diet caused marked increase in tissue concentrations of ascorbic acid and α-tocopherol and depression in serum activity of ceruloplasmin in rats. In this report, an attempt was made to examine the effects of addition of 0.3 %~5% L-cystine, 0.3% L-cysteine and 0.3% L-methionine to 10% casein diet on serum and tissue levels of copper, iron, zinc, ascorbic acid and α-tocopherol. Dietary addition of these sulfur-containing amino acids caused changes in these metabolic parameters. Among these changes, the increases in kidney copper and liver and kidney ascorbic acid and the decrease in the activity of serum ceruloplasmin were prominent and the maximum changes in these responses were observed with the addition of 2. 5-5 % cystine.