Quantitative assessment of human proteinases as agents for chemonucleolysis.
A rabbit model system is described. It allows accurate measurement of the dose-dependent loss of glycosaminoglycan from the nucleus pulposus of lumbar intervertebral discs after injection of a proteinase. At the dose equivalent to that of chymopapain used in human chemonucleolysis, two human serine proteinases, cathepsin G and chymotrypsin, were as effective as chymopapain in removing up to 80% of the glycosaminoglycan from the disc. A cysteine proteinase, cathepsin B released no more than 45% of glycosaminoglycan. X-ray films clearly showed narrowing of the disc space when 30-40% of glycosaminoglycan was removed. The degradation of the nucleus pulposus was seen histologically as loss of toluidine blue metachromasia.
D000818:Animals; D056649:Cathepsin G; D002403:Cathepsins / Q000627:therapeutic use*; D002917:Chymopapain / Q000494:pharmacology; D002918:Chymotrypsin / Q000627:therapeutic use*; D010450:Endopeptidases / Q000627:therapeutic use*; D006025:Glycosaminoglycans / Q000378:metabolism; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D007404:Intervertebral Disc Chemolysis; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D011859:Radiography; D012697:Serine Endopeptidases
D006025:Glycosaminoglycans; D002403:Cathepsins; D010450:Endopeptidases; D012697:Serine Endopeptidases; D002918:Chymotrypsin; C534094:CTSG protein, human; D056649:Cathepsin G; D002917:Chymopapain