**5. Conclusions**

In our study, plasma ADM level was found to be elevated in patients with RA and the origin of ADM was shown to be synovial tissue. ADM may exert anti-inflammatory effects because the cultured RA synoviocytes secrete ADM, have ADM receptors, and inhibit IL-6 production. Therefore, the effects of daily intra-articular injections of ADM into the knees of rabbits with AIA were examined. The results suggest that ADM suppresses the inflammatory response in inflamed joints by inhibiting the expression of TNFα mRNA and increasing IL-6 mRNA level.

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