Objective: To discuss the effect of bone marrow mobilization on chemotaxis of aggregation of macrophages in venous thrombosis. Methods:SD adult rats were divided randomly into normal group,sham operation group,thrombus group and rhG-CSF group.Peripheral blood was harvested at 30min before operation and on the 7th and 14th day after operation.Level of MCP-3 in peripheral blood was detected by ELISA.Inferior vena cava specimens of thromus group and rhG-CSF group were collected at postoperative 7th and 14th day. With the application of RT-PCR,expression of MCP-3mRNA in thrombus was detected.Results:The level of MCP-3 in peripheral blood of rhG-CSF group was significantly higher than that before operation and also higher than the levels of MCP-3 in peripheral blood of sham operation group and thrombus group on the 14th day after operation(P<0.05),and the difference was significant.On the 7th and 14th day after operation,compared with thrombus group,the expression of MCP-3 mRNA in rhG-CSF group remarkablely increased,and the difference Was significant beween these two groups(P<0.01).Conclusion:Brone marrow cell mobilization enhances the chemotaxis of MCP-3 on macrophages.