Fig 1: The effects of matrine on the expression of MMP-2, MMP-3 and MMP-9 in the serum of CIA rats. (a) MMP-2 content; (b) MMP-3 content; (c) MMP-9 content. Norm: normal rats; Cont: control rats; Dex: rats treated with dexamethasone. The data are presented as the mean ± SD (n = 10); * p < 0.05, ** p < 0.01, compared with the Cont.