Developmental pattern of 3-oxo-Ä bile acids in neonatal bile acid metabolism
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چکیده
Aims—To investigate whether a fetal pathway of bile acid synthesis persists in neonates and infants. Methods—3-oxo-Ä bile acids were determined qualitatively and quantitatively in the urine, meconium, and faeces of healthy neonates and infants, using gas chromatography–mass spectrometry. Results—The mean percentage of 3-oxo-Ä bile acids in total bile acids in urine at birth was significantly higher than that at 3 or 7 days, and at 1 or 3 months of age. The concentration of this component in meconium was significantly higher than that in faeces at 7 days and at 1 or 3 months of age. Conclusions—The presence of large amounts of urinary 3-oxo-Ä bile acids may indicate immaturity in the activity of hepatic 3-oxo-Ä-steroid 5â-reductase in the first week of postnatal life. Large amounts of this component in meconium may be due to the ingestion of amniotic fluid by the fetus during pregnancy. (Arch Dis Child 1997;77:F52–F56)
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