In Vitro Studies on the Effect of In Vivo Zinc Deficiency on the Formation of Glycos-Aminoglycans in Rat Costal Cartilage

Abstract

The effects of in vivo zinc deficiency and restricted food intake, on the in vitro synthesis of glycosaminoglycans of rib cartilage were studied in the rat. ³⁵S-sulfate and ¹⁴C-glucosamine were used as precursors. The glycosaminoglycans were separated on microcolumns and specific radioactivities determined for the different fractions.

Chemical analyses showed that zinc deficiency or reduced food intake did not cause any qualitative or quantitative changes in the glycosaminoglycans. The radioassays indicated that zinc deficiency and reduced food intake, alone or combined, caused a somewhat lowered synthetic rate of chondroitin sulfate. In the discussion it is underlined that it seems difficult to determine conclusively the importance of zinc for the formation of the mucopolysaccharides through further in vivo deficiency studies, because of the difficulties to control and evaluate the inanition factor.