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1. The metabolism of [3-14C]coumarin has been studied in rat hepatic microsomes and with two purified cytochrome P-450 isoenzymes. 2. [3-14C]Coumarin was converted by liver microsomes to several polar products including 3- and/or 5-hydroxycoumarin, omicron-hydroxyphenylacetic acid and a major unidentified novel coumarin metabolite. 3. [3-14C]Coumarin was also converted to reactive metabolite(s) as indicated by covalent binding to proteins, and by the depletion of reduced glutathione added to the microsomal incubations. 4. [3-14C]Coumarin metabolism to polar and covalently bound metabolites by rat liver microsomes was induced by pretreatment with phenobarbitone, 3-methylcholanthrene, beta-naphthoflavone, Aroclor 1254 and isosafrole; but not by dexamethasone or nafenopin. 5. The profile of [3-14C]coumarin metabolism to polar products was similar in control and pretreated liver microsomes and in incubations with purified cytochrome P450 IA1 and P450 IIB1 isoenzymes. 6. The results indicate that coumarin is a substrate for isoenzymes of the cytochrome P450 IA and P450 IIB subfamilies. The bioactivation of coumarin by rat hepatic microsomes is postulated to result in the formation of a coumarin 3,4-epoxide intermediate which may rearrange to 3-hydroxycoumarin, be further metabolized to a coumarin 3,4-dihydrodiol, or form a glutathione conjugate.
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
August 1994,
Xenobiotica; the fate of foreign compounds in biological systems,
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
September 1997,
European journal of biochemistry,
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
July 1986,
Biochemical pharmacology,
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
January 1977,
General pharmacology,
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
January 1989,
Drug metabolism reviews,
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
March 1986,
The Journal of pharmacology and experimental therapeutics,
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
September 1980,
Biochemical and biophysical research communications,
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
July 1990,
Biokhimiia (Moscow, Russia),
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
January 1983,
Die Nahrung,
M M Peters, and
D G Walters, and
B van Ommen, and
P J van Bladeren, and
B G Lake
March 1997,
Human & experimental toxicology,
