Effects of 60% oxygen on the morphologic characteristics in lung of neonatal mouse

Objective To determine the effects of moderate hyperoxic exposure (60%)on neonatal mouse lung.Methods Thirty female KM mice were randomly divided into two groups:the normoxia group (21% O2,n=15) and hyperoxia group (60% O2,n=15).Body weight were recorded,histopathology examination of the lung tissue and radical alveoli count (RAC)were carried out.Results Hyperoxia-treated mice had lower body weight than those in normoxia group 7 days after oxygen uptaking (P0.05).The results of HE assay of the hyperoxia group showed that the structure of normal alveoli disappeared,alveolar were fused andalveolar septum were thickened.The RAC value was significantly decreased in the hyperoxia group (P0.01).Conclusion Long-term exposure on high concentration oxygen can result in impediment to growth and impairment of lung development in newborn mouse,which show morphologic changes of lung similar to human bronchopulmonary dysplasia.