目的　了解肿瘤坏死因子 α(TNF α)对体外培养大鼠肝细胞凋亡的作用。方法　在半乳糖胺 (GaIN)或放线菌素D(ActD)致敏情况下 ,加入TNF α,通过光镜、电镜及DNA电泳等方法 ,观察TNF α对体外培养肝细胞凋亡的作用。结果　在大鼠注射GalN后分离肝细胞加入TNF α,ALT上升 ,电镜下可见细胞坏死及凋亡 ;给正常鼠肝细胞ActD加TNF α,光镜下出现典型凋亡细胞 ,DNA电泳出现凋亡的梯形带。结论　TNF α可诱导体外培养肝细胞凋亡 Objective To investigate the effect of tumor necrosis factor α (TNF α) on rat hepatocyte apoptosis in vitro. Methods TNF α was added under the sensitization of galactosamine (GaIN) or actinomycin D (ActD). The effects of TNF α on hepatocyte apoptosis in vitro were observed by light microscope, electron microscopy and DNA electrophoresis. Results After GalN injection, hepatocytes were isolated and TNFα was added. ALT increased, and cell necrosis and apoptosis were observed under electron microscope. Normal rat hepatocyte ActD plus TNFα were detected. Typical apoptotic cells appeared under light microscope and DNA electrophoresis showed apoptosis. Trapezoidal tape. Conclusion TNF α can induce hepatocyte apoptosis in vitro