Table 1

Michaelis-Menten kinetic parameters of sertraline N-demethylation in microsomes of human B-lymphoblastoid cells expressing CYP2B6, CYP2C9, CYP2C19, CYP2D6, or CYP3A4, the contents of five CYP isoforms in pooled human liver microsomes, and the estimated V_max/K_M of each CYP isoform in human liver microsomes

Microsomes	K_M	V_max	V_max/K_M	Contents of CYP in Human Liver Microsomes	EstimatedV_max/K_M in Human Liver Microsomes
	μM	pmol/min/pmol CYP	μl/min/pmol CYP	pmol CYP/mg of protein	μl/min/mg of protein
CYP2B6	30.7 ± 1.2^1-a	2.04 ± 0.36^1-a	0.067 ± 0.012^1-a	41^1-b	2.7^1-c (14%)^1-d
CYP2C9	30.3 ± 5.3	1.73 ± 0.28	0.057 ± 0.006	96	5.5 (29%)
CYP2C19	9.0 ± 1.7	1.11 ± 0.22	0.124 ± 0.016	19	2.4 (13%)
CYP2D6	2.6 ± 0.3	0.79 ± 0.05	0.309 ± 0.022	22	6.8 (35%)
CYP3A4	45.3 ± 8.5	0.57 ± 0.06	0.013 ± 0.002	142	1.8 (9%)

↵1-a The values are expressed as the mean ± S.D. from three different experiments.
↵1-b Provided in data sheets by the manufacturer.
↵1-c Estimated from theV_max/K_M values of cDNA-expressed CYP isoforms and their contents in pooled human liver microsomes.
↵1-d Numbers in parentheses represent the estimatedV_max/K_M as a percentage of the total V_max/K_M values of five CYP isoforms (CYP2B6, CYP2C9, CYP2C19, CYP2D6, and CYP3A4).