Ascorbic Acid and the Calcium Metabolism of Embryonic Chick Tibias 1

Abstract

Summary

Previous work in this laboratory and by others has shown that ascorbic acid is involved in bone matrix production and energy metabolism. However, scant information is to be found concerning a possible involvement of the vitamin in bone mineral metabolism. The present study was undertaken to ascertain if ascorbic acid has an effect on ⁴⁵Ca mobilization from cultured chick tibias. Tibias from 18-day embryos were labeled with ⁴⁵Ca in ovum and cultured for 5 days in chemically defined culture medium. Half the cultures received a single dose of ascorbic acid (50 μg/ml) on day 5. Release of ⁴⁵Ca from the bones during tissue culture and during subsequent short-term incubations was assessed. The results of this study showed that ascorbic acid increased calcium turnover in bone; possibly through increased metabolic activity of the bone cells. The response was transient as the rate of ⁴⁵Ca release in the treated bones eventually returned to the control level.