Thyroxin and development of hepatic microsomal drug oxidation and electron transport in man and rats.

Abstract

The neonatal phase of the ontogenetic pattern of hepatic microsomal mixed function oxidases (HMMFQ) in man and the influence of thyroid hormone on this ontogenetic pattern in rats were studied. In the neonatal period in man, there is a significant deficiency in the activity of hepatic microsomal aminopyrine N-demethylase, aniline p-hydroxylase, NADPH oxidase, NADPH cytochrome c reductase and in the amount of cytochrome P-450 and no measurable activity of NADPH cytochrome P-450 reductase. All of these enzymes except aminopyrine N-demethylase significantly correlated with postconceptional age indicating that significantly developmental events occur during the newborn period. [...]Nous avons étudie l'ontogénèse des oxidases hépatiques à function mixte chèz l'homme, et l'influence des hormones thyroidiennes sur l'ontogénèse de ces enzymes chez le rat. Durant la période néonatale chez l'homme, on observe une déficience significative de l'aminopyrine-N-danethylase, de l'aniline-p-hydroxylase, de l'NADPH oxidase, NADPH cytochrane c reductase et du cytochrome P-450, tandis que l'NADPH cytochrome P-450 reductase n'est pas mesurable