Conjugation Reactions in the Newborn Infant: the Metabolism of Para-aminobenzoic Acid.

It has been shown that the liver of the newborn infant has a limited capacity to perform certain transformation or conjugation reactions when compared to older subjects (Driscoll and Hsia, 1958; Kretchmer, Levine, McNamara, and Barnett, 1956). This limitation is evident in the formation of glucuronides (Brown and Zuelzer, 1958; Vest, 1958) and plays an important role in the genesis of neonatal jaundice. There are indications that other conjugation or detoxification mechanisms are also carried out in a different way from that of later life. The observation that after administration of sodium benzoate the excretion as hippuric acid is incomplete and delayed during the first three to four months of life (Vest, 1959) prompted us to investigate hippurate formation and acetylation in this age period.