title: Placental permeability for morphine-3-beta-D-glucuronide in the guinea pig.
abstract: The fetal Vd and the PS of the major metabolite of morphine, M3G, were studied in pregnant guinea pigs during the last half of gestation. Fetal Vd was determined to be 0.334 ml/g of fetal plus placental weight and did not vary as the gestation progressed. The mean +/- s.e. PS for M3G was 3.7 +/- 0.3 X 10(-5) ml/sec/g and was independent of anaesthesia. This value was consistent with previous studies of other hydrophilic compounds, indicating that diffusion governs the placental passage of M3G. The PS value increased with increasing fetal weight which was consistent with structural changes in the guinea pig placenta as fetal age progresses in late gestation.
authors.affiliation: Department of Pharmacology, School of Medicine, Oregon Health Sciences University, Portland 97201.
authors.forename: G D
authors.initials: GD
authors.lastname: Olsen
authors.forename: S R
authors.initials: SR
authors.lastname: Norris
authors.forename: K M
authors.initials: KM
authors.lastname: Sommer
authors.forename: S M
authors.initials: SM
authors.lastname: Grosso
mesh_terms: D000758:Anesthesia; D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D005260:Female; D005312:Fetal Blood / Q000032:analysis; D005333:Fetus / Q000378:metabolism; D005865:Gestational Age; D006168:Guinea Pigs; D009022:Morphine Derivatives / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D010539:Permeability; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011485:Protein Binding
chemical_list: D001798:Blood Proteins; D009022:Morphine Derivatives; C018108:morphine-3-glucuronide