RESUMO
<p><b>OBJECTIVE</b>To study the effect of carboxyamidotriazole (CAI) on adjuvant arthritis (AA) in rats.</p><p><b>METHODS</b>The rats were randomly divided into normal group,two vehicle groups (polyethylene glycol 400 control and normal sodium control group), CAI-treated groups (10, 20, and 40 mg/kg) and positive control dexamethasone group. Freund's completed adjuvant was used to induce AA in rats. The arthritis index (AI) was scored, and X-ray check of the hind limbs and histopathological examination were performed. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in the inflamed paw tissues were measured.</p><p><b>RESULTS</b>The administration of CAI significantly decreased the AI, restored the body weights, and ameliorated the radiological and histopathological features of joint destruction in AA rats (P<0.05, P<0.01). In addition, CAI reduced the TNF-α, IL-1β, and IL-6 levels in the inflamed paw tissues (P<0.05, P<0.01).</p><p><b>CONCLUSION</b>CAI has therapeutic effect on AA rats, which may be achieved by decreasing the pro-inflammatory cytokines at the site of inflammation.</p>