Fig. 5.

Acute hyperoxia resulted in an adequate oxidative stress response and caffeine reduced the response. Quantitation of lung homogenates by qPCR of a) Nrf2, and b) Keap1 for 3 days’ postnatal oxygen exposure (P3) and recovery (P3_P15), and 5 days’ postnatal oxygen exposure (P5) and recovery (P5_P15), respectively. Data are expressed relative to the normoxia-exposed control group (100%). Error bars represent SEM, n = 7–8/group. *p < 0.05, **p < 0.01, and ***p < 0.001 versus control (NO); #p < 0.05, ##p < 0.01, and ###p < 0.001 versus hyperoxia group (HY) with Mann Whitney test