Table 2.
Voltage-dependent block of sodium currents by chiral analogs of Mex
| Drug | Voltage-dependent block |
Inactivated state block |
|
|---|---|---|---|
| HP −140 mV |
HP −70 mV |
Calculated Ki (μM) | |
| IC50 (μM); Kr | IC50 (μM); K-70 | ||
| R-Me10 | 117 ± 4 | 14.2 ± 1.2 | 11.8 |
| S-Me11 | 82 ± 12 | 6.8 ± 1.2 | 5.5 |
| S-Me12 | 13.1 ± 0.4 | 1.3 ± 0.1 | 1.2 |
| RS-Me13 | 68 ± 3 | 31.7 ± 0.4 | 28.6 |
| RS-Me14 | 56 ± 7. | 21.5 ± 0.4 | 18.8 |
| R-Me15 | 12.8 ± 1.7 | 1.2 ± 0.3 | 1.9 |
Abbreviations: HP, holding potentials; IC50, half-maximal blocking concentration; Ki, affinity constant for the inactivated state; Kr, affinity constant for the resting state.
The columns from left to right are as follows: drug used; IC50 values at two different HP values: −140 and −70mV; inactivated-state block refers to the affinity constants for inactivated sodium channels (Ki) according to the equation in Materials and Methods.