Expression and significance of KL-6/MUC1 in lung tissue of newborn rats with hyperoxia-induced bronchopulmonary dysplasia / 中华实用儿科临床杂志

ABSTRACT

Objective To explore the expression of KL-6/MUC1 and the possible impact on alveolar development in lung tissue of newborn rats with hyperoxia-induced bronchopulmonary dysplasia (BPD).Methods Sixty-four newborn rats were randomly divided into 2 groupshyperoxic group and control group.The rats in hyperoxic group were exposed to high oxygen volume fraction of 900 mL/L,and the rats in control group were exposed to normal oxygen volume fraction of 210 mL/L.The experimental control factors were the same in two groups.Eight rats were randomly selected from each group on day 1,3,7,and 14 after oxygen exposure.The alveolar development was evaluated by the number of radial alveolar count (RAC) and the alveolar area/pulmonary septal area ratio (A/S).The location,distribution,and expression of KL-6/MUC1 in the lung tissue were detected by the fluorescent immunoassay,Western blot,and reverse transcription polymerase chain reaction.Results Compared with the control group,the RAC in hyperoxic group decreased on day 3 and continued to decline on day 14.The A/S in hyperoxic group increased on day 7 and peaked on day 14 (P ＜0.05).KL-6/MUC1 expressed in both bronchial epithelial cells and alveolar epithelial cells of newborn rats.KL-6/MUC1 protein in hyperoxic group peaked on day 1 and decreased later,which was higher than that of the control group (P ＜ 0.05),the level of KL-6/MUC1 was positively correlated with RAC (r =0.707,P ＜ 0.05)and negatively correlated with A/S(r =-0.716,P ＜ 0.05).MUC1 mRNA in hyperoxic group was slightly higher than that in control group,but no significant inter-or intra-group difference was observed (P ＞ 0.05).Conclusions The highest expression of KL-6/MUC1 can be observed in the early phase of hyperoxic exposure,and it decreases to the lowest on the key point of pulmonary development.KL-6/MUC1 may play an important role in the alveolar development.