Effects of Gestational Age, Dexamethasone, and Metopirone on Lecithin Concentration in Fetal Lung Tissue and Amniotic Fluid in Rats and Guinea Pigs

Abstract

There is a significant increase in acetone-precipitable lecithin (APL) concentration with advancing gestation in fetal lung tissue and amniotic fluid in rats. Measurement of the APL concentration in fetal lung tissue and/or amniotic fluid provides an excellent model for evaluation of fetal lung maturation. The surge of lecithin concentration in amniotic fluid lags behind that in fetal lungs by about 1 day. This supports the concept that fetal lungs are a main contributor to the amniotic fluid lecithin pool. Dexamethasone stimulates the biosynthesis of APL in fetal lungs in rats and guinea pigs. These data support the hypothesis that glucocorticoid treatment in the pregnant woman accelerates fetal lung maturation. Metopirone inhibits the biosynthesis of APL in fetal lungs.