Fig. 2

Weight gain of rat pups exposed to normoxia or hyperoxia and treated or not with caffeine for the examination groups a) oxygen exposure from P0 to P3 with monitored body weight on P2, P3, and P15, and b) oxygen exposure from P0 to P5 with monitored body weight on P2, P4, P5, and P15. Values are the mean of the difference in weight of all animals used for immunohistochemical and molecular biological experiments (n = 14–16). Data are expressed relative to the control group at each time point as mean ± SEM. *p < 0.05, **p < 0.01, and ***p < 0.001 versus control (NO); ###p < 0.001 versus hyperoxia group (HY) with Mann Whitney test