Figure 4. As₂O₃ prevented the progression of arthritis in CIA mice.

A. Representative photography of the hind limb from mice were shown. There was no obvious remission of arthritis in CIA control mice on the 1^st(I), 7^th(II) and 14^th(III) day after drug treatment, while clinical symptoms of CIA mice treated with As₂O₃ at dose of 5.0 mg/kg/day had been improved significantly through the 1^st(IV), 7^th(V) and 14^th(VI) days after drug administration. B. Arthritis scores of the mice were evaluated from 19^th day after primary immunization to 40^th day. Mice with CIA were administrated As₂O₃ and MTX intraperitoneally from 26^th day to 39^th day after 1^st immunization. The arthritis scores of normal group were nearly 0 on each test day (data not shown). CIA mice treated with As₂O₃ at doses of 2.0 mg/kg/day (n = 6), 5.0 mg/kg/day (n = 6) and MTX 1.5mg/kg/week (n = 6) showed significant improvement on arthritis score along with the treatment compared to the CIA control group (n = 6, *p < 0.05, **p < 0.01). Data are expressed as the mean ± S.E.M, Con = control = CIA control group. MTX = methotrexate.