Objective: To explore the effect and preliminary mechanism of the Aconiti Lateralis Radix Praeparata for treating adjuvant arthritis (AA) in rats. Method: Ten rats was randomly selected from sixty rats as the normal control

the other rats were used to made the AA model. The model was induced by Freund's complete adjuvant (CFA)

then the rats were divided into drug treatment 4 weeks

model control of drug treatment 4 weeks

Drug treatment 2 weeks and model control of drug treatment 2 weeks. In the drug treatment group the Aconiti Lateralis Radix Praeparata was given intragastrically 0.2 g ·kg-1

once daily.The rats were treated for 2 and 4 weeks respectively. The influence on swelling rate

serum nitric oxide(NO) and interleukin-1β(IL-1β) level were observed after treatment for 2 weeks and 4 weeks. The synovial histopathology was observed under optical microscope too. Result: Drug treatment significantly decreased swelling rate of joints in AA rats and the pathology of synovisl tissues was markedly ameliorated compared with that in the control(P<0.05).After administration for 2 weeks

the levels of serum NO and IL-1β of the rats in drugs groups were significantly decreased compared with those in the control(P<0.05).Continuous administration for 4 weeks

the levels of the targets reached to near the normal leve1. Conclusion: All the results demonstrate that the Aconiti Lateralis Radix Praeparata may play anti-inflammatory and immune-regulatory roles in AA rats through inhibiting the levels of serum NO and IL-1β

adjusting related cytokines expression

then eliminating the joint swelling and improving synovitis pathologically.