The Expression of Hoxa5 gene in fetal lungs in rat model of Nitrofen-induced congenital diaphragmatic hernia

Abstract

Objective To investigate the feature of Hoxa5 gene expression in different development stages of fetal lungs of rats and the role of Hoxa5 in the development of pulmonary hypoplasia with congenital diaphragmatic hernia(CDH).Methods Expression of Hoxa5 mRNA in different development stages(E17.5,E19.5,E21.5)of fetal lungs in rat models of nitrofen-indueed CDH and normal rats was detected by real-time quantitative PCR. Results The expression level of Hoxa5 mRNA kept decreasing during the development of normal lungs at E17.5,E19.5 and E21.5.The Hoxa5 mRNA levels at E21.5 was significantly lower than that of other two gestational ages(P＜0.05).The expression curve of Hoxa5 in the fetal lungs of CDH rats at different development stages was similar to that of normal fetal lungs.There was no significant difference at E17.5 and E19.5 between the CDH group and the control group.The relative quantities of Hoxa5 mRNA in the CDH group was significantly higher than that of the control at E2 1.5(P＜0.05).Conclusions The expression level of Hoxa5 mRNA in normal fetal lungs decreases gradually to a nadir at E21.5,which suggests that lower Hoxa5 mRNA expression at the last stage of gestation may be one of the molecular basis in the morphogenesis of normal lungs.The higher level of Hoxa5 mRNA at E21.5 in CDH group than that in control group suggests that pulmonary hypoplasia in CDH may be caused by increased expression level of Hoxa5 at the last stage of gestation(E21.5). Key words: Hemia; diaphragmatic; Bronchopulmonary; dysplasia; Rats