Influence of Ascorbic Acid on the Absorption of Copper by Rats

Abstract

Experiments were conducted to determine the effects of high levels of ascorbic acid on rats and to determine which step or steps in the utilization of copper are influenced by these high levels of ascorbic acid. The effects of high levels of dietary ascorbic acid on rats are much less severe than those reported for chicks and rabbits. Ascorbic acid significantly depressed the absorption of 64Cu when the acid was put into a ligated intestinal segment along with the radiocopper. A smaller, non-significant, depression in 64Cu resulted when ascorbic acid was given intraperitoneally and 64Cu was put into the ligated segment. In other experiments, the whole-body retention of a single dose of 64Cu was determined. Rats fed a diet containing 1% ascorbic acid retained less of an orally administered dose of 64Cu than did the controls; however, when 64Cu was given intraperitoneally, retention was not significantly affected by 1% dietary ascorbic acid. Thus, the results of both ligated segment studies and whole-body retention experiments indicate that, in rats, ascorbic acid depresses the intestinal absorption of copper, but has little or no effect on copper excretion.