| Objective: We used different therapeutic doses of recombinant human erythropoietin(rhEPO) on SD newborn rats of the new type of bronchial pulmonary dysplasia(BPD) to observe the changes of Bcl-2 and endothelial nitric oxide synthase(eNOS) expression in the lung tissue. eNOS and BCL-2 are two downstream effectors in the PI3K/AKT signaling pathway. This article aimed to detect the protective effect of recombinant human erythropoietin on the lung tissue in the new model of bronchial pulmonary dysplasia, and furthermore to find out the appropriate time of administration and dosage in the experimental conditions. Methods:Lipopolysaccharide(LPS) was used to cause the intrauterine infection of SD newborn rats, and then placed them at 60 percent high-oxygen environment for manufacturing the new BPD model. Before rhEPO intervention, 5 newborn pups from normal pregnant mice and LPS produced pregnant ratswere randomly selected, after anesthetizing them, we choose the lung tissue and stained them by HE, and observed the pathological changes of lung tissue. Next, 18 newborn pups produced by the normal pregnant mice were randomly selectedas air control group. The remaining newborn mice produced by the pregnant mice treated with LPS were placed at the high oxygen environment for manufacturing the new BPD model, and were randomly divided into five groups, namely the control group(group A), rhEPO800 group(group B), rhEPO1000 group(group C), rhEPO1200 group(group D), and rhEPO1400 group(group E), each groups had 18 newborn pups, and treated with rhEPO intervention. The drugs were given subcutaneously in the back of the new BPD model, the first administration time was recorded as the 1st day, 7th and14 days later, Random number table were used to select 6 pups from each group, after anesthetizing them, we choosed their lung tissue and placed at liquid nitrogen, and transferred to-80 ℃ ultra-low temperature refrigerator. RT-PCR and Western blot assay were used to detect the expression levels of eNOS, BCL-2 mRNA and protein in lung tissue of newborn rats new BPD model treated with recombinant human erythropoietin intervention. Results:(1) The results showed the expansion, congestion of pulmonary capillary, and infiltration of inflammatory cells in the alveolar septa and alveolar in the lung tissue of newborn rats produced by the pregnant mice treated with LPS, when compared to the lung tissue of newborn rats produced by the normal pregnant mice group.(2) The BCL-2 mRNA and protein expression levels were significantly lower in newborn rats new BPD model than normal at the group A, while the expression level of eNOS was significantly increased. Compared the B, C, D, E group with the group A, along with the increased concentration of rhEPO administration, the expression levels of BCL-2 mRNA and protein were gradually enhanced, while the expression of eNOS gradually decreased, and more importantly, the expression change of pent-group were most obvious, and was statistically significant(P< 0.05). Conclusions:(1) It was successful to make infection of gestational sac of pregnant mice with LPS.(2) rhEPO resulted in the increased BCL-2 expression, and the decreasedeNOS expression in the new BPD model lung tissue, and the changes become significant evident with the time extension. Between the four different dose groups, with the high dose of upgrading, the expression of two factors between the group become larger, suggesting that rhEPO had a therapeutic effect on the new BPD, but continuous use of 1400IU/kg rhEPO of 14 days, it will get better treatment effect. |
PDF Full Text Request