Fetal lung liquid secretion: insights using the tools of inhibitors and genetic knock-out experiments.

Abstract

At birth, the newborn infant’s organ for gas exchange switches from the placenta to the lungs. Despite major advances in our understanding of the fundamental mechanisms involved in fetal lung development, respiratory disorders continue to be the major cause of perinatal morbidity and mortality. It is therefore not surprising that many investigators continue their research into the mechanisms responsible for the normal development of the fetal lung. The initial key observation that led to our present understanding of fetal lung liquid production occurred in the 1940s when Jost and Policard (1) showed that the fluid within the fetal lung arises from the lung and did not, as it had been believed, represent aspirated amniotic fluid. At this time investigators speculated that the fluid was a transudate arising from the vasculature. However, experiments in the 1960s demonstrated that the fetal lung liquid