Six samples of human epiphyseal cartilage obtained from skeletally normal children, from one day to thirteen years old, were studied.
The collagen and mucopolysaccharide content was rather constant in epiphyseal-plate cartilage of older children, but in the cartilage from the new born infant the amount of galactosamine was significantly increased.
Light protein polysaccharides were extracted from three of the samples. In each case, both chondroitin sulphate and keratosulphate were present in the light protein-polysaccharide complex. The ratio of these substances seemed to be age-dependent. The amino acid composition was very similar to that of other light protein-polysaccharide preparations described in the literature. By electrophoresis, the light protein-polysaccharide fraction did not behave as an homogenous compound. Prior to any enzymatic digestion or alkaline degradation, the light protein-polysaccharide complex in each case could be resolved in two well defined bands by electrophoresis.
The heavy protein-polysaccharides complex had a very low amino sugar content, which increased slightly in the samples obtained from older children.