Table 2.
Biophysical and pharmacological properties of channels containing wild-type and R144 mutant Kv7.2 subunits.
| TEA blockade (% of inhibition) |
||||||||
|---|---|---|---|---|---|---|---|---|
| n | Vmid (mV) | K | Maximal current density (pA/pF) | Current reversal potential (mV) | 0.3 mM | 3 mM | 30 mM | |
| Kv7.2 | 16 | −25.0 ± 1.2 | 14.1 ± 0.7 | 36.5±6.6 | −78±1 | 53.5 ± 11.4 | 87.9 ± 5.1 | 93.0 ± 7.5 |
| Kv7.2+ PIP5K | 14 | −39.5±0.6* | 10.1±0.5 | 107.1±7.3* | – | – | – | – |
| Kv7.2 R144Q | 19 | −43.2 ± 1.6* | 17.2 ± 0.9* | 38.2±5.5 | −79±1 | 57.5 ± 0.4 | 85.5 ± 4.1 | 93.0 ± 4.6 |
| Kv7.2 R144Q + PIP5K | 13 | −81.3±0.7⁎⁎ | 10.5±0.6 | 100.4±17.2⁎⁎ | – | – | – | – |
| Kv7.2 R144W | 15 | −29.1 ± 1.5* | 17.9 ± 1.1* | 25.6 ±3.3 | −79±1 | 60.0 ± 2.8 | 91.7 ± 0.9 | 97.7 ± 0.6 |
| Kv7.2 R144G | 22 | −49.9 ± 1.3* | 12.9 ± 0.4 | 36.0±5.4 | −79±1 | 59.7 ± 3.6 | 93.2 ± 2.1 | 97.2 ± 1.3 |
| Kv7.2 + Kv7.2 R144Q | 12 | −35.7 ± 1.9* | 15.1 ± 0.4 | 39.4 ±4.5 | – | – | – | – |
| Kv7.2 + Kv7.2 R144W | 6 | −27.9±0.9* | 15.8±1.0 | 36.4±10.1 | – | – | – | – |
| Kv7.2 + Kv7.2 R144G | 6 | −36.4 ± 3.4* | 14.8 ± 0.9 | 25.7 ± 6.6 | – | – | – | – |
| Kv7.2 + Kv7.3 | 26 | −29.9 ± 1.1 | 12.7 ± 0.5 | 119.7 ± 12.2 | – | 9.2 ± 2.2 | 42.1 ± 7.4 | 73.1 ± 6.8 |
| Kv7.2 + Kv7.2R144Q + Kv7.3 | 12 | −33.5 ± 1.8 | 11.5 ± 0.4 | 94.8 ± 18.9 | – | 19.0 ±10.0 | 49 ±10.0 | 88 ±2.0 |
| Kv7.2 + Kv7.2R144W + Kv7.3 | 14 | −30.5 ± 1.9 | 11.3 ± 0.5 | 111.9 ± 16.7 | – | 7.8 ± 6.3 | 42.0 ± 8.2 | 78.7 ± 5.9 |
| Kv7.2 + Kv7.2R144G + Kv7.3 | 22 | −37.0 ± 1.4$ | 12.5 ± 0.7 | 87.4 ± 10.3 | – | 8.0 ± 5.3 | 44 .0± 5.0 | 78.5 ± 5.2 |
⁎
p<0.05 versus Kv7.2,
⁎⁎
p<0.05 versus Kv7.2 R144Q
$
p<0.05 versus Kv7.2+Kv7.3.