Propofol inhibits lipopolysaccharide (LPS)-stimulated nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation in microglial cells. (A) NADPH oxidase activity was evaluated with cytochrome c reduction assay in BV2 microglial cells pretreated with propofol for 1 h and stimulated with LPS for a 4 h incubation period. N = 6 independent measurements. (B–D) The protein expressions of NADPH oxidase p22^phox and gp91^phox subunits were measured in primary microglial cells pretreated with propofol for 1 h and stimulated with LPS for a 24 h incubation period. Data are presented as percentage of control-treated values. N = 4 independent measurements. ##P < 0.01, ###P < 0.001 versus control; *P < 0.05, ** P < 0.01 versus LPS group. Statistical analyses were performed by one-way ANOVA with Student–Newman–Keuls post hoc test. GAPDH = glyceraldehydes-3-phosphate dehydrogenase.