Objective:To explore the effects and mechanisms of Additional Si-miao Decoction on gouty arthritis and hyperuricemia in animal models.Methods:Mice were given uric acid ip or yeast extract ig to establish hyperuricemic model

serum uric acid levels were detected.Rat hyperuricemic models were made by orally administering yeast extract

uric acid in serum or urine was detected.Rat acute gouty arthritis model were established by MSU intraarticular injection

the joint swell degree

TNF-α and PGE_2 in synovia were also measured.Results:Additional Si-miao Decoction 24 g·kg-1 and 12 g·kg-1 ig could significantly reduce the serum uric acid level in hyperuricemic mice

meanwhile

12 g·kg-1 and 6 g·kg-1 ig could significantly reduce the serum uric acid level in hyperuricemic rat

together with increasing 24 hrs uric acid excretion.Additional Si-miao Decoction 12 g·kg~(-1) and

6 g·kg-1 ig could obviously restrain the joint swelling degree in the gouty arthritis model rat and improve their gait accordingly.TNF-α and PGE2 levels in the gouty arthritis model rat were also decreased significantly after administration.Conclusions:Additional Si-miao Decoction could obviously ameliorate symptoms of hyperuricacidemia and gouty arthritis.Mechanisms of its effects may consist in accelerating the uric acid excretion and restraining the synthesis of TNF-α

PGE2 in joint.