Table IV.
Bidirectional Permeability Data in Buffer and Plasma for P-gp Substrates. Data Represent the Mean ± SD for n = 3–4 Flux Profiles Per Experiment
| Compound (fu in plasma)a | Assay media | Mass balance (%) | Papp (10−6 cm/s) | Efflux ratio | ||
|---|---|---|---|---|---|---|
| A-B | B-A | A-B | B-A | |||
| 3H-Digoxin (0.61) | Buffer | 100 ± 0 | 100 ± 0 | 2.7 ± 0.21 | 18 ± 0.58 | 6.7 ± 0.56 |
| Plasma | 93 ± 7.6 | 100 ± 5.8 | 4.7 ± 0.15b | 26 ± 1.5 | 5.5 ± 0.36b | |
| 3H-Digoxin (0.61) + 100 μM Verapamil | Buffer | 99 ± 0.58 | 100 ± 0.58 | 4.6 ± 0.46 | 5.8 ± 0.53 | 1.3 ± 0.18 |
| Plasma | 96 ± 2.1 | 99 ± 0.58 | 6.2 ± 1.0 | 7.4 ± 0.49b | 1.2 ± 0.21 | |
| Talinolol (0.48) | Buffer | 99 ± 1.7 | 100 ± 6.1 | 1.1 ± 0.058 | 17 ± 1.5 | 15 ± 1.5 |
| Plasma | 96 ± 1.2 | 98 ± 2.1 | 2.8 ± 0.46b | 34 ± 2.6b | 12 ± 2.2 | |
| Rhodamine 123 (0.35) | Buffer | 99 ± 11 | 99 ± 1.2 | 1.6 ± 0.32 | 9.7 ± 1.1 | 6.1 ± 1.4 |
| Plasma | 98 ± 1.5 | 92 ± 4.7 | 1.2 ± 0.058 | 14 ± 1.5b | 12 ± 1.4b | |
| Verapamil (0.14) | Buffer | 91 ± 8.5 | 83 ± 5.8 | 41 ± 4.6 | 45 ± 1.5 | 1.1 ± 0.13 |
| Plasma | 94 ± 2.1 | 96 ± 5.5b | 110 ± 12b | 120 ± 5.8b | 1.1 ± 0.13 | |
| Saquinavir (0.040) | Buffer | 76 ± 0.58 | 60 ± 5.6 | 2.4 ± 1.4 | 34 ± 2.1 | 14 ± 8.2 |
| Plasma | 100 ± 7.2b | 110 ± 7.5b | 8.4 ± 2.5b | 140 ± 42b | 17 ± 7.2 | |
afu values determined at a similar concentration compared to that used for the Caco-2 experiment
bvalue in plasma was statistically different to the corresponding value in buffer (α = 0.05)