TABLE 1

Initial rate conditions and incubation conditions used to measure kinetic parameters for MNTX reduction to M4 and M5 in liver cytosol of mice, rats, monkeys, and humans, and for naltrexone reduction to 6β-naltrexol in human liver cytosol

Substrate	Species	Linear Range				Conditions for Kinetic Study
		Incubation Time		Protein Concentration		Incubation Time	Protein Concentration	MNTX Concentration
		M4	M5	M4	M5	Incubation Time	Protein Concentration	MNTX Concentration
		min	min	mg/ml	mg/ml	min	mg/ml	μM
MNTX	Mouse	N.A.	0–120	0–6.0	0–6.0	120	4.0	5–2000
	Rat	N.A.	0–120	N.A.	0–6.0	120	4.0	5–5000
	Monkey	0–60	0–60	0–6.0	0–6.0	60	4.0	5–2000
	Human	0–120	0–120	0–4.0	0–4.0	120	1.0	0.5–5000
Naltrexone	Human	0–120		0–0.5		30	0.5	5–1000

N.A., not applicable.