Urinary Protein and Carbohydrate III. Age Differences in Acid Mucopolysaccharides in Human Beings

Summary 1. Urinary acid mucopolysac-charide-glycopeptide fraction and its enzymic digest were fractionated on Dowex 1-X2 column, chloride form. The chemical composition of the eluates was determined. 2. The acid mucopolysaccharide-glycopeptide fraction of normal urine contains a mixture of acid mucopolysaccharide-glycopeptide complexes (70-80%) with a small amount of free acid mucopolysaccharide (20-30%). With increasing age, there were higher percentages of bound acid mucopolysaccharides and less free acid mucopolysaccharides in urine. 3. After enzymic digestion, there was an increase of chondroitin sulfate A or chondroitin sulfate C and a decrease in bound acid mucopolysaccharides in 0.5 M and 1.25 M NaCl eluates. With increasing age, a smaller proportion of the glycopeptides could be digested with a mixture of pronase, trypsin and papain. 4. In normal subjects, 60-90% of acid mucopolysaccharides are equally distributed between the 1.25 M and 1.5 M NaCl fraction. With increasing age, less acid mucopolysaccharides are distributed in these two fractions. 5. The present report suggests the presence of heparitin sulfate, heparin and chondroitin sulfate B as minor components of AMP in normal urine. 6. There was no evidence for the presence of keratosulfate in the normal urines examined. The possible presence of hyaluronic acid in normal urine is not excluded by the results of the present study.