Table 1.
Ventricular INa Biophysical Properties
| WT | Scn2b null | P-value | |
|---|---|---|---|
|
| |||
| N=6 | N=6 | ||
| Voltage dependence of activation | |||
| V1/2(mV) | −55.9 (−60.66,−51.12) | −61.9 (−66.26,−57.53) | P=0.065 |
| κ | 6.2 (5.4,7) | 4.5 (3.8,5.2) | P=0.005 |
| n | 9 | 12 | |
| Voltage dependence of inactivation | |||
| V1/2(mV) | −91.2 (−96.25,−86.2) | −92.4 (−96.7,−88) | P=0.712 |
| κ | −6 (−643,−5.58) | −6.1 (−6.5,−5.76) | P=0.632 |
| C | 0.03 (0.008,0.058) | 0.02 (0.01,0.042) | P=0.390 |
| n | 9 | 12 | |
| Kinetics of inactivation | |||
| τslow (ms) | 5.2 (3.32,7.13) | 4.42 (2.54,6.3) | P=0.516 |
| n | 9 | 9 | |
| τfast (ms) | 1.96 (1.39,2.53) | 1.59 (1.07,2.11) | P=0.317 |
| n | 9 | 12 | |
| Steady-state persistent current | |||
| % of peak current | 3.9 (2.8,4.9) | 2.7 (1.7,3.7) | P=0.100 |
| n | 9 | 11 | |
| Kinetics of recovery | |||
| τ (ms) | 10.4 (7.33,13.4) | 8.6 (5.84,11.3) | P=0.344 |
| n | 8 | 10 | |
Data are expressed as mean (95% CI). Kinetics of inactivation were recorded at a test potential of −45 mV. Persistent INa was recorded at a test potential −45 mV, 50–52 ms after the voltage step.
*
Significance determined by MRE analysis with P < 0.05. n: number of cells tested. N: number of animals tested.