title: Enhanced type X collagen expression in the extruded nucleus pulposus of the chondrodystrophoid dog.
abstract: The causes of early degeneration and calcification of the nucleus pulposus in the chondrodystrophoid dog are poorly understood, and the underlying molecular mechanism of this process has not yet been clearly defined. Type X collagen is one of the key molecules in endochondral bone growth and development, especially matrix calcification. The relationship between type X collagen and disc degeneration and calcification in chondrodystrophoid dogs has not yet been studied. We analyzed the expression of type X collagen in degeneration and calcification of the intervertebral disc in chondrodystrophoid dogs, using type X collagen immunohistochemistry. Control intervertebral discs were collected from five dogs (4 female, 1 male, average age 1.3 years, beagle breed). Degenerated intervertebral discs were surgically removed from 11 canine patients with intervertebral disc extrusion (1 female, 10 male, average age 5.1 years, dachshund breed) in Nippon Veterinary and Animal Science University. All extruded disc samples showed hypertrophic changes and clustering of cells, typical features observed in the degenerated nucleus pulposus. The relative expression of type X collagen in the degenerated nucleus pulposus (84.3 +/- 11.0%) was significantly increased compared to the control nucleus pulposus (5.4 +/- 5.4%). Our findings suggest that type X collagen might contribute to the development of degeneration or calcification in the nucleus pulposus of the chondrodystrophoid dog.
authors.affiliation: Division of Veterinary Surgery, Nippon Veterinary and Animal Science University, Tokyo, Japan. hisanori.itoh@gmail.com
authors.forename: Hisanori
authors.initials: H
authors.lastname: Itoh
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Asou
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hara
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Haro
authors.forename: Kenichi
authors.initials: K
authors.lastname: Shinomiya
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tagawa
mesh_terms: D000818:Animals; D024121:Collagen Type X / Q000378:metabolism*; D004283:Dog Diseases / Q000235:genetics / Q000378:metabolism*; D004285:Dogs; D005260:Female; D005786:Gene Expression Regulation; D020022:Genetic Predisposition to Disease; D007403:Intervertebral Disc / Q000378:metabolism*; D007405:Intervertebral Disc Displacement / Q000235:genetics / Q000378:metabolism / Q000662:veterinary*; D008297:Male
chemical_list: D024121:Collagen Type X