Abstract: Abstract:Objective To observe the therapeutic effect of Simiaoyong’an Decoction (SMYA) on the rat models with thromboangiitis obliterans (TAO),and to explore the action mechanism.Methods The rats were randomly divided into 6 groups:sham operation group,model group,mailuoning group(MLN 2.7 g/kg),high,medium and low doses of SMYA groups (24.3,16.2,8.1 g/kg). The  TAO model was prepared by injecting sodium laurate into the femoral artery of rats.The rats were administered by intragastric administration after prepared model.After 15 d administration,the pathological changes of blood vessel and surrounding tissue were observed with HE staining,the contents of IL-6,TNF-α,CRP,TXB2 and 6-K-PGF1α in plasma were measured by enzyme-linked immunosorbent assay (ELISA),and the content of NO in plasma was measurd by ultraviolet spectrophotometer.Results Compared with model group,the contents of plasma IL-6,TNF-α,TXB2 and CRP in high dose of SMYA(24.3 g/kg) group were significantly decreased,and the contents of NO and 6-K-PGF1α were markedly increased (P<0.05 or P<0.01);the contents of plasma TNF-α in medium and low doses of SMYA (16.2 and 8.1 g/kg) groups were significantly decreased (P<0.01).The  vascular endothelial cells in model group were badly damaged with a large number of  inflammatory cells infiltration,and the  vascular endothelial cells in high dose of SMYA group showed integrity with  little inflammatory cells infiltration.Conclusion SMYA has a good therapeutic effect on rat model of TAO,and the mechanism may be related to anti-inflammatory and  maintaining the balance function of TXA2 and PGI2 in plasma.

Key words: Simiaoyong&rsquo, an Decoction, thromboangitis obliterans, inflammation