SURFACTANT PROTEIN-A IS DECREASED IN A RAT MODEL OF CONGENITAL DIAPHRAGMATIC-HERNIA

We hypothesized that the expression of surfactant protein A (SP-A) wou ld be altered in developing lungs from rat fetuses with congenital dia phragmatic hernia (CDH) induced by maternal ingestion of 2,4-dichlorop henyl-p-nitrophenyl ether (Nitrofen) on Day 9 of gestation. We compare d our findings in fetuses exposed to Nitrofen with a CDH with those in Nitrofen-exposed fetuses without a CDH, and control fetuses whose mot hers received olive oil only, the vehicle for Nitrofen. In late gestat ion, immunocytochemistry using a polyclonal rabbit antihuman SP-A anti body revealed decreased amounts of this protein in lungs from fetuses with CDH. Using immunoblotting, the relative amount of SP-A on Day 21 of gestation was also decreased in lung tissue from fetuses with CDH c ompared with the other groups. Abnormalities of mRNA for SP-A were obs erved in both groups of Nitrofen-exposed fetuses compared with control rats, These findings suggest that there is decreased expression of SP -A in rat fetuses with CDH secondary to Nitrofen exposure.