Fig. 1. Increased nitric oxide production and cyclooxygenase-2 (COX-2) expression by lipopolysaccharide (LPS) treatment in BV2 cells. The concentration of nitrite in the culture supernatants after BV2 cells were treated with 0.1, 1, and 10 µg/ml concentrations of LPS for 24 hours (A) or 1 µg/ml concentrations of LPS for 3, 6, 12, and 24 hr (B), the concentration of nitrite in the culture supernatants was measured by Griess assay. BV2 cells were treated with LPS (1 µg/ml) for 3, 6, 12, and 24 hours. Then, the transcriptional expression of inducible nitric oxide synthase (iNOS) (C) or the translational expression of COX-2 (D) was examined by reverse transcriptase-polymerase chain reaction or immunoblotting, respectively. β-Actin was used as an internal control. CTL, control.