Fig. 5.

Pulmonary antioxidant enzyme levels in C57BL/6J wild-type mice exposed to LPS and hyperoxia during the saccular phase of lung development. C57BL/6J wild-type mice were exposed to 21% O₂ (normoxia) or 70% O₂ (hyperoxia) during postnatal days (PNDs) 1–5 and injected intraperitoneally with 3 (L3) or 6 (L6) mg/kg of LPS or the vehicle (PBS) on PNDs 3–5. Whole-lung tissues were harvested on PND 14 for real-time RT-PCR and immunoblot analyses. A and B: real-time RT-PCR analysis-based determination of NQO1 (A) and HO1 (B) mRNA expression. C: immunoblot determination of NQO1, HO1, and β-actin protein levels. densitometric analysis wherein NQO1 (D) and HO1 (E) band intensity was quantified and normalized to β-actin. Values are expressed as means ± SD (n = 3–7 mice/group). Significant differences between PBS- and LPS-treated mice are indicated by †P < 0.05 and †††P < 0.001 under hyperoxic conditions. Significant differences between treatment-matched mice under normoxic and hyperoxic conditions are indicated by §P < 0.05, §§P < 0.01 and §§§P < 0.001.