Values of IC50 and the Hill coefficient of local anesthetics in μ1 wild-type and mutant channels.
| LA drugs | μ1 wild-type | μ1-N434K1-a | μ1-L437K1-a | μ1-N434D1-a |
|---|---|---|---|---|
| QX-314 | 8.9 ± 0.8 (n = 5) | 155 ± 11 (n = 5) | 74 ± 13 (n = 5) | N.D. |
| [μm]internal | [0.96 ± 0.08] | [1.02 ± 0.07] | [1.13 ± 0.21] | |
| Etidocaine | 27 ± 2 (n = 14) | 194 ± 11 (n = 9) | 85 ± 6 (n = 5) | 19 ± 1 (n = 6) |
| [μm]external | [1.30 ± 0.11] | [1.11 ± 0.07] | [1.12 ± 0.08] | [1.13 ± 0.07] |
| Lidocaine | 239 ± 7 (n = 8) | 696 ± 22 (n = 7) | 453 ± 15 (n = 5) | 108 ± 3 (n = 6) |
| [μm]external | [0.97 ± 0.02] | [0.91 ± 0.02] | [1.12 ± 0.04] | [0.96 ± 0.02] |
| Benzocaine | 802 ± 16 (n = 8) | 1562 ± 48 (n = 8) | 960 ± 54 (n = 6) | 437 ± 14 (n = 5) |
| [μm]external | [1.47 ± 0.05] | [1.88 ± 0.10] | [1.53 ± 0.11] | [1.49 ± 0.06] |
The values of IC50 (mean ± standard error,n = number of experiments) were determined as described in Figure 3. The differences in LA potency between wild-type and mutant channels were all statistically significant. The Hill coefficient is listed in brackets. If estimated by a single concentration of 30 μm QX-314, the IC50 value was 8.8 μm for μ1-N434D, no difference from the wild-type channels.
↵1-a *, p < 0.05.
N.D., not determined.