Figure 3.

Effect of Kentucky reference 1R4F cigarette smoke (0.6 mg WTPM/L) on the lung and liver concentrations of O⁶-MeG in NNK-treated A/J mice. Mice received a one-time, nose-only inhalation regimen of either HEPA-filtered and humidified air (control) or 1R4F cigarette smoke at the previously determined MNLD (0.6 mg WTPM/L) for 2 h to monitor the effect of cigarette smoke on the concentration of O⁶-MeG in mice treated with NNK. A single ip dose of NNK (0, 3.75, or 7.5 μmol/mouse) was administered to mice at the midpoint of the 2-h exposure. Mice were euthanized 4 h after the NNK treatment, lung and liver DNA were analyzed for O⁶-MeG by HPLC. (Mean ± SE; n = 18; * = p < 0.05). (From Brown et al. 1999.)