Urinary Hydroxyproline Excretion in Metastatic Cancer of Bone

Abstract
HYDROXYPROLINE, a nonessential amino acid, comprises 13 per cent of the amino acid content of collagen and is almost absent in the composition of other tissue proteins.1 It is excreted in free and bound forms in human urine.2 , 3 The free form normally makes up only 4 per cent of the total. The remaining hydroxyproline can be released from its bound form (polypeptide) by acid hydrolysis.It has been found to be excreted in the urine in greater than normal quantities in the presence of increased osteoblastic activity as found in normal bone growth, acromegaly and Paget's disease or after the . . .