EFFECT OF AGE ON GLYCOSAMINOGLYCAN SYNTHESIS IN RABBIT ARTICULAR AND COSTAL CARTILAGES

Abstract

The rates of synthesis of chondroitin 4- and 6-sulfate were compared for articular and costal cartilage from rabbits of 3 different ages. Cartilages were labeled in vitro with 3H glucosamine and 35SO4. The glycosaminoglycans were isolated and separated and assayed for radioactivity and uronic acid content. In immature articular cartilage the rate of synthesis of chondroitin 4-sulfate is considerably greater than for chondroitin 6-sulfate, and this condition is reversed as the animal ages. These results are concordant with the known variation in distribution of the glycosaminoglycans with age and suggest that the chondrocyte aleters its synthetic activity with advancing age.