Expression of lung surfactant proteins SP-B and SP-C and their modulating factors in fetal lung of FGR rats.

This study investigated the expression of lung surfactant proteins SP-B and SP-C, and their modulating factors TTF-1 and PLAGL2 in the fetal lung of rats with fetal growth restriction (FGR). The rat FGR model was established by prenatal hypoxia in the first stage of pregnancy, 180 rats for experiment served as hypoxia group, and 197 healthy rats served as normal control group. The FGR incidence in hypoxia was compared with that in normal control group. The histological changes in the fetal lung were observed under the light microscope and electronic microscope in two groups. The SP-B, SP-C, TTF-1 and PLAGL2 proteins were determined in the fetal lung of two groups immunohistochemically. The expression levels of SP-B, SP-C, TTF-1 and PLAGL2 protein and mRNA in the fetal lung of two groups were detected by using Western blotting and RT-PCR respectively. The FGR rat model was successfully established by using hypoxia. Pathologically the fetal lung developed slowly, and the expression levels of SP-B, SP-C, TTF-1 and PLAGL2 protein and mRNA in the fetal lung were significantly reduced in hypoxia group as compared with those in normal control group. It was suggested that maternal hypoxia in the first stage of pregnancy could induce FGR, and reduce the expression of SP-B and SP-C, resulting in the disorder of fetal lung development and maturation.