Age-related changes in O-deethylase and aldrin epoxidase activity in mouse skin and liver microsomes.
The metabolism of three model substrates for the cytochrome P450 dependent mono-oxygenase enzyme system (P450-MMO) was studied in microsomes isolated from skin and liver of young adult and senescent C57B1/6J mice. The substrates chosen were aldrin (AE), 7-ethoxycoumarin (EOC), and 7-ethoxyresorufin (EOR). Both EOC and EOR activities were lower in senescent skin. By contrast, no-age related changes were seen in senescent liver. AE was similar in young and old, in both tissues. We suggest that some important age-related differences in cutaneous xenobiotic metabolism do occur, but that these are not mirrored by hepatic differences, and are substrate specific. Previous work from these laboratories would also suggest significant species differences.
Williams
D
D
Department of Geriatric Medicine, University of Wales College of Medicine, Llandough Hospital, Penarth, South Glamorgan.
Woodhouse
K
K
D000375:Aging / Q000502:physiology*; D000452:Aldrin; D000818:Animals; D003374:Coumarins; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism*; D008658:Inactivation, Metabolic / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008862:Microsomes, Liver / Q000201:enzymology*; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D010078:Oxazines; D012867:Skin / Q000201:enzymology*
D003374:Coumarins; D010078:Oxazines; C017299:7-ethoxycoumarin; C007649:ethoxyresorufin; D006899:Mixed Function Oxygenases; C019647:aldrin epoxidase; D019363:Cytochrome P-450 CYP1A1; D000452:Aldrin