Effect Of Recombinant Human Erythropoietin On PI-3K,AKT Gene Expression And Apoptosis In The Lungs Of Neonatal Rats Exposured To Infection Of Intra-amniotic And Hyperox

Objective：To study the effect of recombinant human erythropoietin (rhEPO) on PI-3K、AKT gene expression and apoptosis in the lungs of neonatal rats exposured to infection of intra-amniotic and hyperoxia. We sought to assess the experimental proofs for the treatmens of bronchopulmonary dysplasia (BPD). Methods：Lipoplysaccharide (LPS) were injected intra-amniotic of scheduled pregnant Sprague-Dawley rats in their later gestation. Then neonatal rats were exposured to60%oxygen, and were administered by rhEPO after first day of hyperoxia exposure, alternate days one. The rats were sacrificed after1day,3days and7days of exposure, Lung cell apoptosis was evaluated by TUNEL assay. The levels of PI-3K mRNA ang AKT mRNA expression were detected by RT-PCR. The levels of AKT and pAKT protein expression were detected by Western blot. Results：The number of lung cell apoptosis increased due to LPS-injected intra-amniotic and hyperoxia-exposed, and it descended obviously after rhEPO-treated (P<0.05). Compared with the air-exposed control group, the levels of PI-3K mRNA, AKT mRNA and their proteins expression, were significantly lower than those in the controls (P<0.05). Meanwhile, the levels of PI-3K mRNA, AKT mRNA and their proteins expression in other two groups which were LPS-injected intra-amniotic hyperoxia-exposed rhEPO-treated group and PBS-injected intra-amniotic hyperoxia-exposed rhEPO-treated group, were significantly higher than those that without rhEPO-treated. All these datas were significant difference (P<0.05) in statistically.Conclusion：It is concluded that the number of lung cell apoptosis may increase due to LPS-injected intra-amniotic and hyperoxia-exposed, meanwhile rhEPO may obviously reduce apoptosis. Thus we inferred that the mechanism of rhEPO antiapoptosis may be related with PI-3K, AKT expression.