Abstract:Objective: To investigate the effect of Shenmai injection on chronic aplastic anemia patients and its mechanism. Method: Sixty-five chronic aplastic anemia patients were randomized into treatment group and control group. The patients of the treatment group were treated by injecting Shenmai injection and taking western medicine orally, those of the control group taking western medicine orafly only, then the effect was evaluated. The concentration of tumor necrosis factor-α(TNF-α) in blood serum was detected and the apoptosis of bone marrow CD34+ cell was analysed by DNA ISEL technic before and after treatment. Result: The effective rate of the treatment group and the control group was 63.6 % and 40.6 % respectively, the effect of the Shenmai injection on the treatment group was obviously better than that of the control group (P<0.01). Before treatment, the concentration of TNF-α in blood serum and the apoptosis rate of bone marrow CD34+ cell of the chronic aplastic anemia patient were higher than normal (P< 0.01). After treatment, the concentration of TNF-a in blood serum of the treatment group decreased obviously(P< 0.01), and the apoptosis rate of bone marrow CD34+ cell of the treatment group also decreased (P< 0.05), which had significant difference compared with those of the control group(P< 0.05). Conclusion: Shenmai injection is efficient to chronic aplastic anemia. The mechanism is decreasing the concentration of TNF-a in blood serum and the apoptosis rate of bone marrow CD34+ cell.