Enzyme Studies in the Articular Cartilage of Diabetic Rats and of Rats Bearing Transplanted Pancreatic Islets

The articular cartilage of normal rats, of rats made diabetic with streptozotocin, and of rats made diabetic with streptozotocin and subsequently transplanted with isologous pancreatic islets was examined for the activities of enzymes engaged in the synthesis and degradation of glycosaminoglycans (mucopolysaccharides). The activities assayed were those of the degrading enzymes B-glucuronidase, B-acetyglucosaminidase, B-acetylgalactos-aminidase, B-galactosidase, and those active in synthesis: uridine-diphosphate dehydrogenase, ghicose-6-phosphate dehyrogenase, and phosphofructokinase. In the diabetic animals all enzyme activities were increased, those of the degrading enzymes more than those of the others. Implantation of pancreatic islets reversed the changes produced by diabetes, enzyme activities returning to near-normal levels.