Kinetic parameters for OAT1-mediated uptake by wild-type and mutant transporters
Mutations were created by site-directed mutagenesis of both hOAT1 and cyOAT1 at position 203. Statistical analyses were performed by one-way analysis of variance followed by Tukey’s multiple comparisons test. N ≥ 2; * represents comparison with human; # represents comparison between cynomolgus monkey and cynomolgus monkey A203S.
| Parameter | Human | Cynomolgus Monkey | Cynomolgus Monkey A203S | Human S203A |
|---|---|---|---|---|
| Km (μM) | 72.6 ± 20 | 254 ± 0.1**** | 105 ± 27### | 216 ± 19*** |
| Vmax (nmol/mg/min) | 4.6 ± 1.4 | 2.5 ± 0.2 | 2.8 ± 0.1 | 3.6 ± 0.7 |
| Vmax/Km (μl/mg/min) | 63 | 10 | 27 | 17 |
↵*** P < 0.001; ****P < 0.0001; ###P < 0.001.