Bile-Salt Metabolism in the Newborn

Abstract

Bile-salt synthesis and bile-salt pool size were determined in five normal newborn infants by isotope dilution with the use of nonradioactive deuteriumlabeled bile salts. Bile-salt isotope ratios were determined with a gas liquid chromatography-mass spectroscopy-acceleration voltage alternation system. The results establish that the newborn infant is capable of bile-salt synthesis. The average cholate synthesis rate was 110 mg per square meter per day, with an average pool size of 290 mg per square meter; both values are reduced when compared to values obtained from normal adults. This discrepancy suggests that "immaturity" of the mechanisms that control bile-acid metabolism and turnover may be one of the factors responsible for the inefficient fat absorption observed in normal newborn infants.