Effect of prednisolone on the glycosaminoglycan components of the regenerating articular cartilage.

Investigations were performed on the effect of prednisolone (0.5 mg/kg) on the regenerating femoral articular cartilage of the knee joint in dogs that had been subjected to semiarthroplasty. After 70 days of prednisolone treatment the dogs were killed and the regenerating articular cartilage was removed, minced, and dried with acetone. The acetone-dried material was used for the determination of galactosamine, glucosamine, uronic acid, sulphate, sialic acid and hydroxyproline. Prednisolone treatment elicited a quantitative increase in galactosamine (30.2%), uronic acid (76.2%), and sulphate (9.1%), while no difference was observed in sialic acid content between the treated and untreated groups. From the molar ratio of the measured components it appears that prednisolone produced an increase in chondroitin sulphate and hyaluronic acid, and a decrease in the keratosulphate content of cartilage. By comparing the values measured in the regenerating articular cartilage of control and prednisolone-treated dogs with the values obtained in the mature articular cartilage, we may conclude that prednisolone--at least as regards the glycosaminoglycans of the ground substance--exerts an accelerating effect on cartilage regeneration.