Comparisons between extracted and residual proteoglycans on the glycosaminoglycan level and changes with ageing

Sheep nasal cartilage from animals of five different ages were studied. Significant variations in the composition and on the extractability of the tissue occur with ageing. The ratio chondroitin sulphate to keratan sulphate in extracted and residual proteoglycans does not change in the same manner with ageing. The relative distribution of molecular sizes of keratan sulphate differs between extracted and residual proteoglycans. Hyaluronic acid and chondroitin sulphate appear homogeneous on the gel chromatography for all ages both in extracted and residual proteoglycans.