Onset of xenobiotic metabolism in children: toxicological implications

摘要

The level of expression of cytochromes P450 shows a wide interindividual variability, depending on the age and tissue investigated. Several lines of evidence in- dicate that the human foetal liver is an active site for the biotransformation of drugs, chemicals and hydro- phobic endogenous molecules. Besides this high degree of maturity, many studies have shown a discrepancy in the onset of activities and suggested that cytochrome P450 isoforms developed independently. Thus, many Cytochromes P450 are absent or barely detectable in the foetal liver and develop postnatally.