Changes in apoptosis and Fas/FasL expression in newborn rats with acute lung injury.

【Objective】To observe the expression of apoptosis related gene Fas/FasL on lung injury caused by hypoxia and inhaled 100% O_2 after hypoxia. Two lung injury rat models were established by hypoxia or inhaled 100% O_2 respectively. Apoptosis of the lung tissue was observed with the methods of Tunel and in situ hybridization. mRNA expression of Fas/FasL was detected by SqRt-PCR. Apoptosis of rat pulmonary alveolar epithelial cells and pneumoangiogram endothelial cells appeared after 4 hours in two groups. And the index of apoptosis increased with the time passing by ( P =0.003, 0.005 respectively). And expression of Fas/FasL mRNA was up-regulated in two groups, which in inhaled pure oxygen group was higher than in hypoxia group. [Conclusion] Apoptosis and upregulated Fas/FasL mRNA plays an important role on lung injury which is caused by hypoxia or inhaled pure oxygen after hypoxia.