Abstract: AIM: To observe the effect of puerarin on the contents of MCP-1,TNF-ɑ and pulmonary ultrastructure after thrombolytic therapy in acute pulmonary thromboembolism.METHODS: Twenty-four Japanese rabbits were randomly divided into sham operation group, thrombolysis-only group, and puerarin group.Acute pulmonary thromboembolism models of rabbits were established with injection of autologous blood clots through the right heart catheters. Haemodynamic monitoring was performed by introducing heart catheter through right jugular vein. These rabbits were sacrificed at 4 h after thrombolysis, the lung was removed and the ratio of wet to dry of lung tissue weight (W/D) was detected. The contents of MCP-l and TNF-α were also investigated with ELISA. The myeloperoxidase (MPO) activities of lung tissue were detected with colorimetry. The ultrastructure of lung tissue was observed by electronic microscope.RESULTS: The pulmonary arterial mean pressure (mPAP) was decreased immediately at 1 h after thrombolysis both in thrombolysis-only group and puerarin group (P<0.01), the mPAP in puerarin group were significantly lower than those in thrombolysis-only group at 1 h after thrombolysis(P<0.05); The contents of MCP-l and TNF-α, the value of W/D and the MPO activity of lung tissue were significantly increased in thrombolysis-only group and puerarin group than those of sham operation group; The histopathologic analysis showed the injuries of vascular endothelial cells and alveolar cells in thrombolysis-only group were more severe than those in puerarin group.CONCLUSION: Chinese herb puerarin can protect lung against reperfusion injury after thrompolytic therapy in acute pulmonary thrombembolism which may associate with the action of inhibiting inflammation reaction by reducing the contents of MCP-1 and TNF-α.

Key words: Puerarin, pulmonary thromboembolism, thrombolytic therapy, MCP-1, TNF-α