Table 1

Michaelis-Menten constant (Km), maximum velocity (Vmax), inhibition constant for diclofenac (Ki), and intrinsic clearance (Cli) of codeine-6-glucuronide formation in homogenates of liver and small intestinal enterocytes

μM pmol/min/mg μM μl/min/mg
Liver donor no. 1154755.889.
Liver donor no. 2170764.61311.860.077
Liver donor no. 3121140.860.80.686.82.120.050
Small intestine donor no. 2214931111.10.510.005
Small intestine donor no. 315652195.800.280.004

Mean Km and Vmax of codeine-6-glucuronidation in liver homogenate: 1488 μM, 93.6 pmol/min/mg; mean Km andVmax of codeine-6-glucuronidation in enterocyte homogenate (small intestine): 1857 μM, 8.5 pmol/min/mg; meanKi of diclofenac on codeine-6-glucuronidation in liver homogenate: 7.9 μM.