A pathological study of experimental chemonucleolysis with collagenase.
This study was undertaken to examine and quantitate the chemical injury and repair of the dog nucleus pulposus in collagenase-induced chemonucleolysis. Thirty three adult mongrel dogs were used into which the purified collagenase was injected at a rate of 200 units. The dogs were sacrificed after roentgenography. Disc specimens were stained primarily with safranin-O for microscopic study, and fresh tissues were used for electron microscopic study. For immunohistochemical analysis, paraffin sections were reacted with anti-bovine types I, II and III collagen antibodies. Two weeks after the injection, the height of the injected disc was reduced by about 50% and there was no sign of recovery for 52 weeks. There was a profound loss of safranin-O stainability in the nucleus pulposus, annulus fibrosus and cartilagenous endplate. By 8 weeks, regeneration of the nucleus pulposus began and chondrocytes appeared from the junctional area. The regenerated nucleus pulposus was stained well with safranin-O and consisting largely of type II collagen immunohistochemically. In the regenerated nucleus pulposus, collagen fibers and proteoglycans were reconstructed in a net-work with hyaluronic acids.
Tsuchida
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Department of Orthopaedic Surgery, School of Medicine Chiba University, Japan.
D000818:Animals; D003094:Collagen / Q000032:analysis; D004285:Dogs; D007150:Immunohistochemistry; D007403:Intervertebral Disc / Q000032:analysis / Q000473:pathology* / Q000503:physiopathology; D007404:Intervertebral Disc Chemolysis / Q000379:methods; D003012:Microbial Collagenase / Q000494:pharmacology*; D012038:Regeneration
D003094:Collagen; D003012:Microbial Collagenase