Influence of sulfasalazine on established collagen arthritis in rats

Collagen induced arthritis (CIA) in rats is an experimental model that is characterized by an erosive synovitis associated with periostitis and both peripheral and axial ossifying enthesopathy. The influence of long-term therapy with sulfasalazine (80 mg/day on weekdays) on established CIA in Wistar Furth rats was investigated. Clinical and X-ray examination showed a significant improvement in the joint lesions of the uninjected paws in the treated rats as compared to controls. This effect was, however, delayed. On the other hand, periosteal new bone formation and caudal enthesopathy (spondylodiscitis) were not altered by the treatment.