Pathological sections of ankle joints and molybdenum target X-rays of rat limb joints. Pathological sections of ankle joints from (A) a normal rat, (B) a CIA rat at 10 weeks post-primary immunization and (C) a CIA rat at 21 weeks post-primary immunization (magnification, ×400). Molybdenum target X-rays of the rat limb joints from (D) a normal control group rat at 10 weeks post-primary immunization, (E) a CIA rat at 10 weeks post-primary immunization, (F) an artesunate-treated (20 mg/kg/day) rat at 10 weeks post-primary immunization, (G) a normal control group rat at 21 weeks post-primary immunization, (H) a CIA rat at 21 weeks post-primary immunization and (I) an artesunate-treated (20 mg/kg/day) rat at 21 weeks post-primary immunization. CIA, collagen-induced arthritis.