Fig. 1.

Effects of Papaver nudicaule extracts on cytotoxicity and NO production. a RAW264.7 cells were treated with Papaver nudicaule extracts (15.625–500 μg/ml) for 24 h. Cell viability was measured by MTT assays. b RAW264.7 cells were treated with Papaver nudicaule extracts (125–500 μg/ml) and LPS (100 ng/ml) for 24 h. NO production was examined in the culture supernatants. Data are presented as mean ± SD from at least three independent experiments in triplicate. *P < 0.05, **P < 0.01 and ***P < 0.001 indicate statistically significant differences compared with the group treated with LPS alone