Spontaneous action potential characteristics by genotype in SAN myocytes
| . | WT (n = 19/15a) . | Kcna1−/− (n = 14/11) . | ||
|---|---|---|---|---|
| Control | DTX-K | Control | DTX-K | |
| APD50, ms | 46.5 ± 12.9 | 52.6 ± 9.0* | 58.4 ± 16.9† | 59.7 ± 18.2 |
| APD90, ms | 88.0 ± 22.9 | 106.8 ± 24.6*** | 113.2 ± 22.5†† | 116.3 ± 23.2 |
| MDP, mV | −58.9 ± 7.1 | −58.3 ± 7.5 | −58.8 ± 6.3 | −59.0 ± 6.7 |
| DDR, mV/s | 151.4 ± 76.5 | 107.1 ± 104.2* | 129.9 ± 44.9 | 124.4 ± 48.7 |
| . | WT (n = 19/15a) . | Kcna1−/− (n = 14/11) . | ||
|---|---|---|---|---|
| Control | DTX-K | Control | DTX-K | |
| APD50, ms | 46.5 ± 12.9 | 52.6 ± 9.0* | 58.4 ± 16.9† | 59.7 ± 18.2 |
| APD90, ms | 88.0 ± 22.9 | 106.8 ± 24.6*** | 113.2 ± 22.5†† | 116.3 ± 23.2 |
| MDP, mV | −58.9 ± 7.1 | −58.3 ± 7.5 | −58.8 ± 6.3 | −59.0 ± 6.7 |
| DDR, mV/s | 151.4 ± 76.5 | 107.1 ± 104.2* | 129.9 ± 44.9 | 124.4 ± 48.7 |
Values are means ± SD. Sample numbers (n) represent the number of cells recorded followed by the number of mice. WT, wild-type. APD50 and APD90, action potential durations at 50% and 90% of repolarization, respectively.
*, P < 0.05 and ***, P < 0.001 versus WT control (paired two-tailed Student’s t test); †, P <0.05 and ††, P <0.01 versus WT control; (unpaired two-tailed Student’s t test).
Measurements could not be obtained for one cell following DTX-K treatment so the sample size for the WT DTX-K column represents 18 cells from 14 mice.