GSR and bronchopulmonary dysplasia: In 1978, Yam et al. detected the increase of superoxide dismutase (SOD), glutathione peroxidase (GP), glutathione reductase (GR), and glutathione (GSH) in newborn rats increased by exposing to hyperoxia, which proved that the above substances increased the tolerance of lung tissue to hyperoxia injury, and successfully established a BPD animal model of newborn rats with hyperoxia (20).