Sulphate and glucuronic acid conjugation of harmol in human fetal and adult liver tissue.

Glucuronidation of harmol in microsomal preparations and sulphate conjugation in hepatic 105,000 g supernatant fractions were studied comparatively in human fetal and adult liver subcellular preparations. The formation of harmol sulphate in the fetal liver was slightly lower than in the adult liver and considerably lower than in rat liver. No glucuronidation of harmol was found in fetal liver, while the activity in adult liver was 30-80 nmol glucuronide formed/2 mg/20 min. In an ontogenic perspective, our in vitro findings are consistent with drug metabolic studies in the human neonate in whom negligible glucuronidation but well-developed sulphate conjugation of paracetamol has been demonstrated.