Table 1.
Electrophysiological properties of TRPM8(+) DRG neurons in wild type and TASK-3 KO mice
| Wild type | TASK-3 KO | ||
|---|---|---|---|
| (n = 21) | (n = 16) | p value | |
| RMP (mV) |
54.6 ± 0.8 | −50 ± 2.0 | < 0.05 |
| AP Threshold (mV) |
−32.8 ± 0.7 | −31.4 ± 0.8 | 0.19 |
| AP Overshoot (mV) |
33.82 ± 1.27 | 33.82 ± 1.27 | 0.24 |
| AP Amplitude (mV) |
104.7 ± 1.2 | 97.4 ± 1.9 | < 0.001 |
| AP Duration (ms) |
1.12 ± 0.02 | 1.20 ± 0.05 | 0.24 |
| AP Depolarization Rate (mV/ms) |
314 ± 5 | 268 ± 23 | 0.11 |
| AP Repolarization Rate (mV/ms) |
−104 ± 5 | −84 ± 6 | < 0.05 |
| AHP Peak (mV) |
−71.1 ± 0.8 | −66.2 ± 1.1 | < 0.001 |
| Input Resistance (MΩ) |
857 ± 65 | 971 ± 90 | 0.30 |
| Rheobase Current (pA) |
22.9 ± 1.6 | 22.5 ± 1.7 | 0.88 |
| Sag Ratio (%) |
0.78 ± 0.02 | 0.73 ± 0.02 | 0.07 |
All recordings were performed in perforated whole-cell current clamp mode. After determining the resting membrane potential (RMP), the potential was adjusted to −60 mV. Action potential (AP) overshoot is the absolute peak voltage value from 0 mV. AP amplitude is measured from the overshoot peak to the most negative voltage reached during the afterhyperpolarization (AHP) immediately after the AP. AP duration is measured at half-maximal amplitude. The sag ratio, a measure of the Ih current, was assessed from the amplitude ratio of the voltage at peak and at steady state during a 150 ms hyperpolarizing current pulse of −120 pA. All statistical comparisons were performed with an unpaired t-test.