title: Biochemical characterization of cartilage affected by osteochondritis dissecans in the humeral head of dogs.
abstract: OBJECTIVE
  To determine glycosaminoglycan (GAG) concentration and immunohistochemical staining characteristics of type-I, -II, and -X collagen from cartilage affected by osteochondritis dissecans (OCD) in dogs.
  
  
  METHODS
  31 dogs with OCD and 11 clinically normal purpose-bred dogs.
  
  
  METHODS
  Cartilage samples were evaluated microscopically, and GAG content was determined. Immunohistochemical staining was performed for type-I, -II, and -X collagen. Sections were subjectively evaluated for location and intensity of staining.
  
  
  RESULTS
  Cartilage affected by OCD had a variety of pathologic changes and significantly lower GAG concentrations than did normal cartilage. Normal cartilage had no detectable type-I collagen. For dogs < 9 months of age, cartilage affected by OCD had significantly more type-I collagen but significantly less type-X collagen than did control cartilage. For dogs > 12 months of age, cartilage affected by OCD contained significantly more type-I collagen than did control cartilage. There was a significant negative correlation between immunoreactivity of type-I collagen and that of type-II and -X collagen. A significant positive correlation was found between immunoreactivity of type-II and -X collagen.
  
  
  CONCLUSIONS
  Cartilage affected by OCD contains less GAG, more type-I collagen, and less type-X collagen, compared with normal cartilage. A direct correlation between these changes and the etiopathogenesis of OCD was not established.
authors.affiliation: Comparative Orthopaedic Laboratory, College of Veterinary Medicine, University of Missouri-Columbia, 65211, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Tomlinson
authors.forename: J L
authors.initials: JL
authors.lastname: Cook
authors.forename: K
authors.initials: K
authors.lastname: Kuroki
authors.forename: J M
authors.initials: JM
authors.lastname: Kreeger
authors.forename: M A
authors.initials: MA
authors.lastname: Anderson
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000737:chemistry* / Q000473:pathology; D003094:Collagen / Q000378:metabolism; D004283:Dog Diseases / Q000378:metabolism* / Q000473:pathology; D004285:Dogs; D005260:Female; D006025:Glycosaminoglycans / Q000378:metabolism*; D006811:Humerus / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry / Q000662:veterinary; D008297:Male; D010008:Osteochondritis Dissecans / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D018709:Statistics, Nonparametric
chemical_list: D006025:Glycosaminoglycans; D003094:Collagen