PT  - JOURNAL ARTICLE
AU  - P H Beaune
AU  - P G Kremers
AU  - L S Kaminsky
AU  - J De Graeve
AU  - A Albert
AU  - F P Guengerich
TI  - Comparison of monooxygenase activities and cytochrome P-450 isozyme concentrations in human liver microsomes.
DP  - 1986 Jul 01
TA  - Drug Metabolism and Disposition
PG  - 437--442
VI  - 14
IP  - 4
4099  - http://dmd.aspetjournals.org/content/14/4/437.short
4100  - http://dmd.aspetjournals.org/content/14/4/437.full
SO  - Drug Metab Dispos1986 Jul 01; 14
AB  - Concentrations of three human liver microsomal cytochrome P-450 isozymes and 20 different monooxygenase activities were determined in human liver microsomal preparations. The results of correlation analysis suggest that: there are important variations in the amounts of the three cytochrome P-450 isozymes measured, particularly P-450(8) and P-450(9); aldrin epoxidase, d-benzphetamine N-demethylase, and S-warfarin 4-hydroxylase activities are linked to cytochrome P-450(5); aryl hydrocarbon (benzo(a)pyrene) hydroxylase and 4-nitroanisole-O-demethylase activities are linked to P-450(8); hydroxylations at the 4'-, 6-, 7-, and 8-positions of R-warfarin are closely linked to each other but are not correlated with other measured monooxygenase activities or P-450 isozyme levels; and P-450(9) is not related to any of the catalytic activities tested. Thus, certain monooxygenase activities can be attributed to specific cytochrome P-450 isozymes. This approach should be useful in suggesting the roles of different cytochromes P-450 in drug metabolism in man which can be further examined using in vitro and in vivo methods.