Objective:To study the expression levels of endothelin-1(ET-1)in lung vascular endothelium,bronchial and alveolar epithelia,thromboxane A2(TAX2)and prostacyclin(PGI2)in plasma and arterial blood gas in acute pulmonary thromboembolism(APTE)of rabbit,and explore the effects of thrombolytic(urokinase,UK)and ant-inflammatory therapy(xuebijing)on their expressions. Methods:Thirty rabbits were randomly divided into the control group,the pulmonary thromboembolism(PTE)model group,the Xuebijing therapy group,the UK therapy group and an UK + Xuebijing therapy group,with 6 rabbits in each group. The PTE model was established by intravenous injection of autologous blood clots. Arterial bloodgas were analyzed,and Plasma’s concentrations of TXA2 and PGI2 by were examined by radioimmunoassay before and 1 h,2 h,4 h,8 h after injection. Pathological changes of the lung were examined with light microscope,and the expression levels of ET-1 in lung vascularendothelium,bronchial and alveolar epithelia were examined by immunohistochemistry. Results:①Arterial blood gas analysis showed that PO2 and PCO2 were obviously lower in PTE model group than the control group,no significance found in Xuebijing group and PTE group;the PO2 improved earlier in UK and UK + Xuebijing groups than in PTE group;②radioimmunoassay showed that TXA2 and PGI2 in the PTE group increased at 1 h,peaked at 2 h,decreased at 4 h,which also were higher than those in the control group at 1 h,2 h,4 h(P < 0.01),In the treat group TXA2 and PGI2 increased at 1 h,peaked 2 h,decreased after 2 h,also decreased fasted than those in PTE group at 1 h,2 h and 4 h irrespectively(P < 0.01),especially in UK + Xuebijing group. There were no differences in TXA2 and PGI2 before injection and 8 h after injectionin in each groups;③Histopathological study showed that lung injury was obvious in the PTE,but was less inUK and Xuebijing groups,and least inthe UK + Xuebijing group;④the immunohistochemistry results showed in the PTE and Xuebijing groups,the expression levels of ET-1 in lung vascular endothelium,bronchial and alveolar epithelia were significantly higher compared those in the control group. The UK and UK + Xuebijing groups were significantly lower in ET-1 as compared to the PTE group. Conclusion:After APTE,thrombolytic and anti-inflammatory treatment could improve arterial blood gas,decrease TXA2,PGI2 and acute lung injury induced by ET-1. Thus,Xuebijing injection may alleviate pulmonary inflammation and decrease acute lung injury in APTE . Anti-inflammatory therapy should be considered in APTE when thrombolytic treatment was used.