Fig. 6.

Effect of replacement by fresh culture medium before LPS administration on inhibition by GGA of NO production in LPS-treated RAW 264 cells. GGA (0, 20, 40, or 80 µM) was added to the medium 2 h before LPS administration and subsequently culture medium was replaced by fresh one without GGA just before LPS addition. Cells were further incubated in the presence of LPS (1 µg/ml) for 24 h at 37°C under a 5% CO₂ and 95% air atmosphere. The level of NO in the medium was measured as described in Materials and Methods. Data points represent the means ± SE (n = 3).