Biochemical characterization of cartilage affected by osteochondritis dissecans in the humeral head of dogs

Am J Vet Res. 2001 Jun;62(6):876-81. doi: 10.2460/ajvr.2001.62.876.

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.

Animals: 31 dogs with OCD and 11 clinically normal purpose-bred dogs.

Procedure: 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 and clinical relevance: 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.

MeSH terms

  • Animals
  • Cartilage, Articular / chemistry*
  • Cartilage, Articular / pathology
  • Collagen / metabolism
  • Dog Diseases / metabolism*
  • Dog Diseases / pathology
  • Dogs
  • Female
  • Glycosaminoglycans / metabolism*
  • Humerus / metabolism
  • Humerus / pathology
  • Immunohistochemistry / veterinary
  • Male
  • Osteochondritis Dissecans / metabolism
  • Osteochondritis Dissecans / pathology
  • Osteochondritis Dissecans / veterinary*
  • Statistics, Nonparametric

Substances

  • Glycosaminoglycans
  • Collagen