Table 2.
Electrophysiological properties of sodium channels in HEK293 cells co-expressing SCN5A, PMCA4b, nNOS, and either WT or mutant SNTA1
| Samples | Peak INa† | Activation | Inactivation | Late INa | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| pA/pF | n | V1/2(mV) | K | n | V1/2(mV) | K | n | % | n | |
| WT-SNTA1 | -185 ± 18 | 33 | -40.7 ± 0.9 | 4.0 | 30 | -77.4 ± 0.9 | 5.0 | 30 | 0.155±0.03 | 30 |
| G460S-SNTA1 | -254 ± 23* | 12 | -39.8 ± 1.1 | 4.0 | 12 | -72.8 ± 0.8* | 5.5 | 12 | 0.361±0.06* | 12 |
| T372M-SNTA1 | -271 ± 28* | 13 | -40.8 ± 1.0 | 4.1 | 12 | -74.9 ± 0.5* | 5.1 | 13 | 0.412±0.07* | 13 |
| S287R-SNTA1 | -284 ± 35* | 14 | -42.5 ± 2.3 | 4.2 | 9 | -74.0 ± 1.4* | 5.0 | 12 | 0.357±0.05* | 12 |
| T262P-SNTA1 | -335 ± 51* | 17 | -40.3 ± 0.6 | 4.1 | 9 | -74.1 ± 0.7* | 5.0 | 16 | 0.223±0.04 | 12 |
| P56S-SNTA1 | -221 ± 30 | 14 | -42.8 ± 1.4 | 4.3 | 14 | -79.4 ± 0.9 | 5.0 | 14 | 0.080±0.04 | 14 |
| G54R-SNTA1 | -240 ± 40 | 12 | -39.9 ± 1.0 | 4.0 | 9 | -76.0 ± 1.0 | 5.0 | 9 | 0.148±0.04 | 10 |
| G460S-SNTA1 + L-NMMA | -231 ± 39 | 6 | -43.0 ± 1.7 | 4.2 | 5 | -78.9 ± 1.2 | 5.3 | 6 | 0.167±0.07 | 5 |
| T372M-SNTA1 + L-NMMA | -228 ± 34 | 8 | -41.7 ± 2.1 | 4.3 | 5 | -76.7 ± 1.1 | 5.0 | 8 | 0.203±0.04 | 7 |
| S287R-SNTA1 + L-NMMA | -258 ± 41 | 6 | -41.4 ± 1.4 | 4.0 | 5 | -77.0 ± 1.6 | 5.1 | 6 | 0.194±0.06 | 5 |
*
P < 0.05 versus WT-SNTA1.
†
I Na = Sodium current