Effects of chronic vanadium pentoxide administration on L-ascorbic acid metabolism in rats: influence of L-ascorbic acid supplementation.

1. Rats toxicated with vanadium pentoxide showed drastic retardation in growth rate and supplementation of L-ascorbic acid to these rats could not reverse this effect. The urinary excretion of L-ascorbic acid and D-glucuronic acid was decreased in the toxicated group of rats. 2. Considerable lowering of L-ascorbic acid content of the liver tissues of rats was observed under vanadium toxicated conditions. Supplementation of L-ascorbic acid to this group raised the tissue Vitamin C reserve considerably. 3. The normal histological patterns of the liver and kidney tissues of rats were severely disturbed under vanadium toxicated conditions. L-ascorbic acid supplementation to this group of rats showed marked signs of restoration in this respect. 4. Vanadium pentoxide treatment brought about a significant reduction in the biosynthetic capacity of L-ascorbic acid, along with an enhanced utilization of this vitamin. Subsequent supplementation of L-ascorbic acid to the toxicated group of rats was found to be effective in reversing these effects almost to the basal level.