Kinetic data for the two main metabolic steps of (R,S-)MDMA
Units used are: Vmax, picomoles per minute per picomole; and Km, micromolar.
MDA Formation | DHMA Formation | |||||
|---|---|---|---|---|---|---|
| Vmax | Km | Vmax | Km | |||
| R,S-MDMA | ||||||
| CYP1A2 | 36 ± 2.5 | 519 ± 68 | 6.9 ± 0.2 | 35 ± 2.9 | ||
| CYP2B6 | 55 ± 2.2 | 205 ± 15 | Not determined | Not determined | ||
| CYP2C19 | 27 ± 1.7 | 144 ± 17.4 | 12 ± 0.5 | 76 ± 12.7 | ||
| CYP2D6 | 5.7 ± 1.0* | 13 ± 4.6* | 13 ± 0.4 | 0.3 ± 0.05 | ||
| CYP3A4 | Not determined | Not determined | 2.2 ± 0.6* | 52 ± 19* | ||
| R-MDMA (from racemic MDMA) | ||||||
| CYP1A2 | 19 ± 1.3 | 285 ± 33 | 3.0 ± 0.5 | 19 ± 0.5 | ||
| CYP2B6 | 32 ± 1.5 | 131 ± 11 | Not determined | Not determined | ||
| CYP2C19 | 13 ± 0.9 | 156 ± 18.1 | Not determined | Not determined | ||
| CYP2D6 | 2.0 ± 0.9* | 5.2 ± 1.1* | 6.6 ± 0.2 | 0.2 ± 0.02 | ||
| CYP3A4 | Not determined | Not determined | 2.3 ± 1.2* | 46 ± 10* | ||
| S-MDMA (from racemic MDMA) | ||||||
| CYP1A2 | 16 ± 1.5 | 244 ± 42 | 3.9 ± 0.6 | 16 ± 0.6 | ||
| CYP2B6 | 26 ± 1.3 | 106 ± 9.6 | Not determined | Not determined | ||
| CYP2C19 | 16 ± 1.1 | 53 ± 7.0 | 12 ± 0.4 | 38 ± 5.1 | ||
| CYP2D6 | 2.4 ± 0.8* | 2.5 ± 0.4* | 6.5 ± 0.2 | 0.2 ± 0.03 | ||
| CYP3A4 | Not determined | Notdetermined | 1.1 ± 0.5* | 27 ± 8.2* | ||
| R-MDMA | ||||||
| CYP1A2 | 101 ± 6.8 | 814 ± 91 | 3.6 ± 0.2 | 64 ± 2.6 | ||
| CYP2B6 | 31 ± 3.4 | 93 ± 29 | Not determined | Not determined | ||
| CYP2C19 | 17 ± 1.7 | 158 ± 32 | 3.4 ± 0.1 | 29 ± 4.8 | ||
| CYP2D6 | 7.0 ± 3.3* | 6.6 ± 2.9* | 5.4 ± 0.2 | 4.4 ± 0.9 | ||
| CYP3A4 | Not determined | Not determined | 2.8 ± 0.2* | 387 ± 46.7* | ||
| S-MDMA | ||||||
| CYP1A2 | 74 ± 4.4 | 873 ± 79 | 3.7 ± 0.3 | 65 ± 3.9 | ||
| CYP2B6 | 28 ± 3.9 | 100 ± 36 | Not determined | Not determined | ||
| CYP2C19 | 14 ± 0.7 | 78 ± 8.1 | 7.5 ± 0.3 | 14 ± 3.9 | ||
| CYP2D6 | 3.6 ± 1.3* | 4.0 ± 1.9* | 5.9 ± 0.4 | 2.7 ± 0.9 | ||
| CYP3A4 | Not determined | Not determined | 4.4 ± 0.2* | 460 ± 42.1* | ||
↵* Vmax1 and Kml.