Lung hypoplasia and surfactant system immaturity induced in the fetal rat by prenatal exposure to nitrofen.

We studied the biochemical maturity of the lungs of fetuses born to rats exposed to nitrofen on day 9.5 of gestation. In comparison with controls, nitrofen-treated fetuses had pulmonary hypoplasia (decreased lung/body weight), lung hypocellularity (low DNA content) and cellular atrophy (low protein/DNA and phospholipid/DNA) on gestational days 19 and 21. Treated animals with congenital diaphragmatic hernia (CDH) also had cell atrophy and surfactant immaturity (decreased disaturated phosphatidylcholine/DNA) near term. Our data demonstrate that nitrofen causes lung hypoplasia and some degree of surfactant system immaturity that is particularly prominent in fetuses with CDH.