title: Age-related changes in the proportion of types I and III collagen.
abstract: Previous studies of the age-related changes in interstitial collagens, have suggested that the proportion of type III collagen compared with type I decreases with age. In this study collagen concentration and the proportion of types were measured in heart, lung and skin of male Lewis rats aged between 1 day and 2 years. Collagen concentration, based on hydroxyproline levels, increased in all tissues up until 6 months of age, thereafter it increased in heart and lung, yet decreased in skin. The relative proportions of types I and III collagen were assessed after cyanogen bromide digestion of the tissue and separation of the resultant peptides by sodium dodecyl sulphate polyacrylamide gel electrophoresis. At 2 weeks of age collagen type III represented about one-third of types I and III in all tissues. After this age the proportion of type III increased up to 1 year in both heart (53.9 +/- 1.8%) and lung (47.7 +/- 2.8%), whereas it decreased in skin (18.6 +/- 1.5%). These data show that there are age-related changes in both collagen concentration and the relative proportions of types I and III collagen, but that the direction of these changes differs between tissues.
authors.affiliation: Department of Thoracic Medicine, University of London, (UK).
authors.forename: P K
authors.initials: PK
authors.lastname: Mays
authors.forename: J E
authors.initials: JE
authors.lastname: Bishop
authors.forename: G J
authors.initials: GJ
authors.lastname: Laurent
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology; D003094:Collagen / Q000032:analysis*; D004591:Electrophoresis, Polyacrylamide Gel; D008168:Lung / Q000032:analysis; D008297:Male; D009206:Myocardium / Q000032:analysis; D051381:Rats; D011917:Rats, Inbred Lew; D012867:Skin / Q000032:analysis
chemical_list: D003094:Collagen