RELATIONSHIP BETWEEN URINARY HYDROXYPROLINE AND GROWTH*

Abstract

Beginning with the report of Ziff, Kibrick, Dresner, and Gribetz (2), evidence accumulated in recent years has indicated that urinary hydroxyproline excretion reflects collagen metabolism, since collagen is the only protein in the body that contains hydroxyproline in significant amounts (3). Ziff and co-workers, observing that the excretion of this amino acid in peptide form was greater in children than in adults, suggested that the level of urinary hydroxyproline might be re- lated to the size of the metabolically active, solu- ble collagen pool available for breakdown. The results of a number of investigations (4-7) have supported this suggestion.