The transfer and metabolism of 7-ethoxycoumarin and androstenedione during the in vitro perfusion of the human placental lobule.
1. The in vitro metabolism of 7-ethoxycoumarin in the perfused placental lobule has been investigated and compared with that of androstenedione. 2. Perfusion studies showed that the placental lobule was capable of sustaining the metabolism of 7-ethoxycoumarin to 7-hydroxycoumarin for at least one hour but at a considerably lower rate than that for the conversion of androstenedione to oestrone under the same conditions. 3. Following perfusion with androstendione disproportionately large amounts of oestrone were found in the maternal outflow and ostradiol in the foetal outflow. 4. Appreciably more testosterone was formed when the foetal side of the lobule was perfused with androstenedione than when the maternal side was perfused. 5. The data indicate that the human placenta has only a limited capacity for the metabolism of xenobiotics.
Cummings
A J
AJ
Section of Perinatal and Child Health, MRC Clinical Research Centre, Harrow, Middlesex, UK.
Copas
D K
DK
Kaelin
A C
AC
Rosankiewicz
J R
JR
Landon
M J
MJ
D000735:Androstenedione / Q000378:metabolism*; D003374:Coumarins / Q000378:metabolism*; D004970:Estrone / Q000378:metabolism; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D010477:Perfusion; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D013739:Testosterone / Q000378:metabolism; D014468:Umbelliferones / Q000378:metabolism
D003374:Coumarins; D014468:Umbelliferones; D004970:Estrone; C017299:7-ethoxycoumarin; D013739:Testosterone; D000735:Androstenedione; C031477:7-hydroxycoumarin