RESUMO
Objective To investigate the role of nuclear factor-kappa B (NF-κB)signaling pathway in propofol-induced suppression of up-regulation of inducible nitric oxide synthase (iNOS) gene expression in LPSstimulated RAW264.7 cells.Methods RAW264.7 cells were purchased from cell bank of Chinese Academy of Sciences and cultured in DMEM culture medium containing 10％ fetal bovine serum.The cells were seeded in 6 cm diameter dishes (3 ml/dish) or in 6-well plates (2 ml/well) with a density of 5 × 105/ml and randomly divided into 3 groups ( n =18): normal control group (group C),group LPS (group L)and group LPS + propofol (group LP).The cells were incubated with LPS 1 μg/ml in groups L and LP.Propofol 50μmol/L was added to the culture medium at 2 h before LPS in group LP.Cells were harvested at 30 min after being stimulated with LPS.Phosphorylation of IκB kinase(p-IKK) and NF-κB activity were detected by Western blot.The expression of iNOS mRNA was determined after 6 h exposure of the cells to LPS.Results LPS significantly up-regulated the expression of p-IKK and iNOS mRNA and increased NF-κB activity in group L as compared with group C.Propofol pretreatment significantly attenuated the effects of LPS on p-IKK,iNOS mRNA expression and NF-κB activity.Conclusion NF-κB signaling pathway is involved in the propofol-induced suppression of up-regulation of iNOS mRNA expression in LPS-stimulated RAW264.7 cells.