Apparent Km and apparent Vmax values and intrinsic formation clearances (CLint = Vmax/Km) for the formation of K11777 metabolites by human liver microsomes
| Sample | N-Oxide K11777 | β-Hydroxy-homoPhe K11777 | N-Desmethyl K11777 |
|---|---|---|---|
| K m(μmol · l−1) | |||
| HLF10 | 9.9 | 13.9 | 15.1 |
| HLF42 | 10.7 | 14.7 | 16.9 |
| HLM06 | 15.6 | 16.9 | 12.7 |
| HLM23 | 19.6 | 21.7 | 28.5 |
| mean ± S.D. | 14.0 ± 4.5 | 16.8 ± 3.5 | 18.3 ± 7.0 |
| V max(pmol · min−1 · mg−1) | |||
| [pmol · min−1 · pmol P450−1] | |||
| HLF10 | 2744 [9.7] | 1144 [4.1] | 1833 [6.5] |
| HLF42 | 8150 [14.3] | 2835 [5.0] | 4724 [8.3] |
| HLM06 | 1724 [4.5] | 640 [1.7] | 966 [2.5] |
| HLM23 | 1226 [4.0] | 432 [1.4] | 755 [2.4] |
| mean ± SD | 3460 ± 3189 | 1263 ± 1090 | 2069 ± 1830 |
| [8.1 ± 4.9] | [3.1 ± 1.8] | [4.9 ± 3.0] | |
| CLint(μl · min−1 · mg−1) | |||
| mean ± S.D. | 303 ± 319 | 83 ± 82 | 126 ± 110 |
Data are presented as mean ± standard deviation. Liver microsomes were prepared from four patients (two female [HLF] and two male [HLM]). Apparent Km values were calculated after linearization according to Hanes-Woolf using the Sigma-Plot software (version 5.0; SPSS Inc.).