Table 1.
Kinetic data for zidovudine glucuronidation by native and detergent-activated human liver microsomes in phosphate- and Tris-buffered incubations (0.1 m, pH 7.4)a.
| Microsome treatment | Km (µm) | Vmax (pmol min−1 mg−1) | CLint (µl min−1 mg−1) |
|---|---|---|---|
| Native, | 926 ± 197 | 920 ± 280 | 1.04 ± 0.42 |
| phosphate buffered | (682, 1170) | (527, 1268) | (0.53, 1.56) |
| Native, | 1235 ± 219 | 1684 ± 394 | 1.37 ± 0.30 |
| Tris-buffered | (963, 1506) | (1195, 2174) | (1.00, 1.73) |
| Activated (Brij58), | 1011 ± 261 | 3695 ± 954* | 3.66 ± 1.40* |
| phosphate-buffered | (687, 1334) | (2311, 4680) | (1.92, 5.39) |
| Activated (Brij58), | 1390 ± 221 | 5193 ± 907* | 3.79 ± 0.74* |
| Tris-buffered | (1116, 1664) | (4068, 6319) | (2.87, 4.71) |
a
Data presented as mean ± s.d., with 95% confidence intervals in parenthesis, for microsomes from 5 human livers.
*
P < 0.05 compared with values for phosphate- and Tris- buffered native microsomes.