Aim To investigate the effects of interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) on endothelial lipase(EL) in rat aortic smooth muscle cell(ASMC).Methods The rat ASMC were obtained from thoracic aortas and cultured by tissue explant method.Passage 3~5 cells were used in experiment,and were randomly divided into 3 groups:GroupⅠ:treated without intervention as the control;GroupⅡ:the rat ASMC were treated in serum-free culture medium containing IL-1β(1 to 30 μg/L) for 24 hours;GroupⅢ:TNF-α(5 to 50 μg/L) for 24 hours.The levels of EL were tested by the method of enzyme linked immunosorbent assay(ELISA) and reverse transcription polymerase chain reaction(RT-PCR).Results Smooth muscle cells were treated with increasing concentrations of IL-1β,ranging from 1 μg/L to 30 μg/L.The relative increases in EL protein and mRNA were greater at the highest concentrations(30 μg/L) of IL-1β.There was a significant difference between the intervention group and the control group(P<0.05).There were significant differences among the intervention groups(P<0.05).The relative increases in EL protein and mRNA were greater at the highest concentrations(50 μg/L) of TNF-α.There was a significant difference between the intervention group and the control group(P<0.05).There were significant differences among the intervention groups(P<0.05).Conclusion Smooth muscle cells were treated with increasing concentrations of IL-1β and TNF-α,then secreted protein and EL mRNA were noted.