Objective: To study the therapeutic mechanism of Santeng Dingtong recipe (STDT) on monosodium urate crystal (MSU) induced rabbit arthritis.Methods: Forty-two rabbits were randomly divided into six groups

7 in each group. Group 1 received 0.9% saline 2.5 ml/kg per day by gastrogavage (ig) for 10 days; Group 2

3 and 4 received STDT 0.125 g/kg

1.0 g/kg and 8.0 g/kg per day respectively by ig for 10 days; Group 5 received colchicine 4.5 mg/kg per day by ig for 4 days; and Group 6 was untreated. MSU crystals 10 mg /500 μl containing polymyxin B 10 u/ml was injected into the knee joints of Group 1–5 to make rabbit arthritis models. Leukocytes in synovial lavage fluids was then counted and differentiated; pathological injury of synovial membranes was observed under HE staining; interleukin-1 beta (IL-lβ)

tumor necrosis factor alpha (TNFα) and leukotriene B4 (LTB4) content in synovial lavage fluids were determined by ELISA.Results: MSU caused a rapid leukocyte infiltration and increased production of IL-lβ

TNFα and LTB4 2 hrs after intra-articular injection. STDT inhibited neutrophil infiltration in synovial fluids dose-dependently

protected the synovial membrane against pathological injury and reduced the production of IL-lβ

TNFα and LTB4; while colchicine did not decrease the level of TNFα

but significantly inhibited neutrophil infiltration in synovial fluid and reduced the production of IL-11β and LTB4.Conclusion: STDT exerts an anti-inflammatory effect in rabbit model of acute MSU arthritis

its mechanism being probably due to the decrease of IL-1β

TNFα and LTB4 synthesis.