. Author manuscript; available in PMC: 2008 May 21.

Published in final edited form as: Mol Pharmacol. 2007 Dec 21;73(3):1029–1036. doi: 10.1124/mol.107.043869

Table 1.

Kinetic parameters for midazolam metabolism by liver and intestinal microsomes. All values are the means of three independent experiments ± S.D. Incubations were performed as described in Materials and Methods.

		1′-OH Midazolam			4-OH Midazolam
Microsomes	Strain	K_m^a	V_max^b	V_max/K_m^c	K_m^a	V_max^b	V_max/K_m^c
Liver	Cyp3a^+/+	0.95 ± 0.18	630 ± 29	662	8.43 ± 0.27	224 ± 12.7	26.6
	Cyp3a^−/−	6.38 ± 1.2	735 ± 11	115	17.5 ± 6.9	49.8 ± 5.0	2.36
	Human	2.93 ± 0.33	2097 ± 155	715	38.7 ± 6.3	1226 ± 87	27.8
Intestine	Cyp3a^+/+	10.4 ± 1.8	62.3 ± 3.2	6.02	55.9 ± 2.0	38.0 ± 5.2	0.68
	Cyp3a^−/−	-^d	-^d	-^d	-^d	-^d	-^d
	Human	1.61 ± 0.04	596 ± 18	369	24.5 ± 3.3	330 ± 11	13.5

K_m expressed in μM

V_max expressed in pmol/min/mg protein

V_max/K_m expressed in μL/min/mg protein

No metabolite detected (detection limit <5 pmol/min/mg protein)