Dynamic changes of extracellular matrix in newborn rat with hyperoxia-induced pulmonary injury

Objective To investigate dynamic changes of extracellular matrix(ECM) deposition in newborn rat with hyperoxia-induced pulmonary injury. Methods The levels of type Ⅰcollagen, fibronectin(FN) and hyaluronic acid(HA) were assayed with enzyme-linked immunoadsorbent technique, and pathological changes of lung were observed from lung specimen of day 1,3,7,14 and 21 in 30 full-term newborn rats with hyperoxia-induced pulmonary injury and 30 control full-term newborn rats.Results Hyperoxia during neonatal period resulted in alveolar inflammation in early stage, proliferation of fibroblast and collagen deposition in late stage. Increased levels of type Ⅰcollagen, FN,and HA of model group respectively on day 7,3 and 1with peak on day 21,7 and 3 were found.Conclusion (1)Prolonged exposure to hyperoxia for the newborn rats creates lesion which was very similar to lung fibrosis;(2)Increased HA, FN and type Ⅰcollagen of lung associated respectively with alveolar inflammation, proliferation of fibroblast and lung fibrosis during exposure to hyperoxia.