MMP9 and arthritic joint disease: mRNA levels of IL-1β, matrix metalloproteinase-1 (MMP-1), tumour necrosis factor-α (TNF-α) levels, anti-tartrate acid phosphatase (TRAP), matrix metalloproteinase-9 (MMP-9), tissue proteinase K (CtsK) and integrin β3 (β3-Integrin) in the joints of mice were determined.<h4>Results</h4>The paw edema score at 18-30 d and the paw arthritis score at 12-30 d in CIA group were higher than those in control group, and the paw edema score and paw arthritis score at 24-30 d in NF-kB inhibitor group were lower than those in CIA group.