Urinary Metabolites of Collagen

Academic Article


  • The urinary excretion of hydroxyproline and hydroxylysine has been a commonly used standard for the evaluation of collagen degradation. Free urinary hydroxylysine does not appear to give a quantitative estimate of degraded collagen. However, a variable proportion of hydroxylysine residues in collagen have been shown to be glycosylated as a-l,2-glucosylgalactosyl-O-hydroxylysine (GGH) and fl-l-galactosyl-Ohydroxylysine (GH), these hydroxylysylglycosides (HLG) are also present in urine. Urinary hydroxyproline and hydroxylysine can be determined by amino acid analysis or by a colorimetric assay. Analysis is carried out by the method of Miller and Piez or by use of any single-column amino acid analyzer system. In colorimetric assay hydroxyproline is oxidized to pyrrole and the pyrrole is quantitated by a colorimetric reaction with Ehrlich's reagent. There are number of procedures for determination of urinary HLG levels. These procedures generally consist of three basic steps: (a) sample preparation; (b) ion-exchange chromatography; and (c) quantitation by one of three methods, the ninhydrin assay for free amino groups, a colorimetric assay for hydroxylysine, or the orcinol-H2SO4 assay for hexose. © 1982, Elsevier Inc. All rights reserved.
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    Author List

  • Segrest JP
  • Start Page

  • 398
  • End Page

  • 410
  • Volume

  • 82
  • Issue

  • C