目的 研究阿司匹林联用华法林对肝药物代谢酶CYP3A4活性的影响及其机制。方法 不同质量浓度的阿司匹林、华法林及联合用药处理HepG2细胞48 h，采用MTT法检测细胞存活率；通过荧光素酶报告基因技术检测各组对PXR转录酶活性和酶CYP3A4活性的影响；采用荧光定量PCR法和Western blotting法检测HepG2细胞的酶CYP3A4的mRNA和蛋白表达水平。结果 与对照组比较，阿司匹林组、联合用药组细胞的孕烷X受体（PXR）转录酶活性、酶CYP3A4活性均显著降低（P<0.01），CYP3A4 mRNA和蛋白表达水平显著降低（P<0.05、0.01），华法林组均无显著差异。结论 阿司匹林联用华法林能够抑制药物代谢酶CYP3A4活性，其机制可能是通过抑制PXR受体的mRNA和蛋白表达实现的。

Objective To study the effects of aspirin combined with warfarin on CYP3A4 and its mechanism. Methods HepG2 cells were treated with different concentrations of aspirin, warfarin and its combine for 48 h. cell survival rate was determined by MTT method. The transcriptional activation of PXR and activities of CYP3A4 were detected by luciferase reporter gene technique. The expressions of CYP3A4 mRNA and protein in HepG2 cells were detected by PCR and Western blotting method. Results Compared with the control group, the transcriptional activation of PXR and activity of CYP3A4 in aspirin group and combined groups were significant decreased (P<0.01), and the expressions of CYP3A4 mRNA and protein in HepG2 cells were significant decreased (P<0.05, 0.01), but there were no differences in warfarin group. Conclusion Aspirin combined with warfarin can inhibit the activity of drug metabolizing enzyme CYP3A4, which may be related to inhibition of the expressions of mRNA receptor PXR and protein.