TABLE 1.
Kinetic parameters of 6β-OH-T, 2β-OH-T, and 2α-OH-T metabolites for recombinant CYP3A4, CYP3A5, and CYP3A7 enzymes
| Testosterone Metabolites | CYP3A4 |
CYP3A5 |
CYP3A7 |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Fit (n) | Vmax (nmol/min/nmol P450) | S50 (µM) | Fit (n) | Vmax (nmol/min/nmol P450) | S50 (µM) | Fit (n) | Vmax (nmol/min/nmol P450) | S50 (µM) | |
| 6β-OH-T | Hill (1.0) | 95.5 ± 8.0 | 26.1 ± 6.4 | Hill (1.4) | 17.4 ± 0.6 | 41.6 ± 4.1 | Hill (1.4) | 0.72 ± 0.03 | 11.8 ± 1.2 |
| 2β-OH-T | Hill (0.9) | 5.4 ± 0.4 | 25.8 ± 6.5 | Hill (1.6) | 4.5 ± 0.1 | 40.3 ± 3.5 | Hill (1.2) | 0.15 ± 0.01 | 12.2 ± 1.7 |
| 2α-OH-T | NA | ND | NA | NA | ND | NA | Hill (1.5) | 0.51 ± 0.03 | 6.6 ± 0.9 |
Hill, Hill equation; n, Hill coefficient; NA, not applicable; ND, not detected; P450, cytochrome P450.