Drug metabolism by the fetal stump-tailed monkey (Macaca arctoides). Hepatic microsomal N-demethylation and glucuronidation as measured by radiometric assays.
Sensitive radiometric assays were adapted to study the development and kinetics of meperidine and methadone N-demethylation and morphine glucuronidation by microsomes isolated from livers of fetal stump-tailed macaques (Macaca arctoides). Times in development selected for study were midterm, three-quarter term, near term and newborn (0.5 h and 14 days). With appropriate attention to keeping blanks low, hepatic drug metabolism was demonstrable as early as midterm. Vmax for the N-demethylation reactions (nmole product/10 min/mg microsomal protein) increased throughout gestation, whereas the apparent Kms remained constant. With respect to morphine glucuronidation, all kinetic parameters remained constant throughout the last half of gestation.
D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005865:Gestational Age; D005966:Glucuronidase / Q000378:metabolism*; D000882:Haplorhini; D008099:Liver / Q000033:anatomy & histology / Q000196:embryology / Q000378:metabolism*; D008251:Macaca / Q000196:embryology / Q000378:metabolism*; D008614:Meperidine / Q000378:metabolism; D008691:Methadone / Q000378:metabolism; D008862:Microsomes, Liver / Q000201:enzymology / Q000378:metabolism*; D009020:Morphine / Q000378:metabolism; D009929:Organ Size; D010089:Oxidoreductases, N-Demethylating / Q000378:metabolism; D011506:Proteins / Q000032:analysis
D011506:Proteins; D009020:Morphine; D003577:Cytochrome P-450 Enzyme System; D008614:Meperidine; D010089:Oxidoreductases, N-Demethylating; D005966:Glucuronidase; D008691:Methadone