ABSTRACT
OBJECTIVE: Hemophilic arthropathy, which results from recurrent intra-articular bleeding, is a proliferative synovitis, but the sequence of pathogenic events in hemophilic synovitis (HS) is not known in detail. To investigate the pathogenic mechanism of HS and to evaluate the suppressive effect of rifampicin for HS, we designed this study. METHODS: Twenty normal male New Zealand white rabbits weighing approximately 2,000 gm were used for this study. We injected 1 mL of autologous whole blood of the rabbits into the right knee joint and normal saline into the left knee joint (control) thrice a week for 10 weeks and sacrificed 10 of them. We injected 10 mg of rifampicin into the right knee joint of HS, which is 5 rabbits of remained 10, once a week from 11th week until 15th week. At 11th week and 20th week, the rabbits were sacrificed and both knee joints of each rabbit were opened, synovial membrane specimens were collected and examined pathologically and biologically such as mRNA of IL-1, TNF-alpha, MMP-1 and MMP-3 in hemophilic synovium using by real-time quantitative PCR method (comparative Ct method). RESULTS: At 20th week, in rifampicin treated group showed decreased proliferative, and infiltrated mononuclear cells compared with control group. And mRNA of TNF-alpha, IL-1 and MMP-3 levels were decreased also. CONCLUSION: In animal model of HS, histological changes showed the same as human hemophilic synovitis. And this study suggested that rifampicin has a controlling effect on the inflammatory process of HS by suppression of inflammatory cytokine production in the experimental hemophilic synovitis model.