目的　研究电磁脉冲 (EMP)对肺癌细胞A5 4 9凋亡的影响。方法　以场强为 6× 10 4V/m的EMP辐照 5次 /2min ,然后采用细胞计数、MTT、流式细胞术及免疫组化染色的图像分析 ,观察EMP对肺癌细胞A5 4 9的损伤作用 ,所有数据经SPSS8 0软件进行分析。结果　EMP可明显抑制肺癌细胞A5 4 9的增殖与活力。流式细胞术证明 ,A5 4 9细胞发生明显的凋亡。免疫组化的图像分析表明 ,伴有不同程度的Bcl 2蛋白表达的下调及P5 3蛋白表达的上调。结论　EMP可诱导肺癌细胞A5 4 9的凋亡。Bcl 2及P5 3蛋白参与了A5 4 9细胞的凋亡过程 Objective To study the effect of electromagnetic pulse (EMP) on the apoptosis of A549 cells. Methods The EMPs with a field intensity of 6 × 10 4 V / m were irradiated 5 times / 2 min. Then the cell damage, the damage of E 4 against A549 cells were observed by using cell counting, MTT, flow cytometry and immunohistochemical staining. All data were analyzed by SPSS8 software. Results EMP could significantly inhibit the proliferation and viability of A549 cells. Flow cytometry showed that A549 cells showed obvious apoptosis. Immunohistochemical image analysis showed that down-regulation of Bcl 2 protein expression and up-regulation of P5 3 protein were associated with different degrees. Conclusion EMP can induce the apoptosis of A549 cells. Bcl 2 and P5 3 proteins are involved in the apoptosis of A549 cells