Table 1.
Intrinsic electrophysiological properties of insular cortical neurons.
| Neuron subtype | Pyramidal Mean ± SEM | Fast spiking Mean ± SEM | Regular spiking Mean ± SEM | Late spiking Mean ± SEM |
|---|---|---|---|---|
| The number of neurons | 66 | 35 | 10 | 11 |
| Vma (mV) | -72.8 ± 1.0 | -73.6 ± 1.2 | -67.6 ± 2.7 | -74.0 ± 1.8 |
| Input resistance (MΩ) | 167.8 ± 8.7 | 176.9 ± 19.2 | 232.5 ± 33.7 | 232.5 ± 33.7 |
| Action potential | ||||
| Threshold (mV) | 50.5 ± 0.5 | -50.9 ± 0.5 | 50.7 ± 0.9 | 48.5 ± 0.9 |
| Amplitude (mV) | 94.2 ± 1.8 | 76.2 ± 2.2*** | 82.4 ± 5.3 | 82.4 ± 2.8* |
| Half duration (ms) | 1.63 ± 0.06 | 0.76 ± 0.04*** | 1.3 ± 0.1### | 0.96 ± 0.10*** |
| AHPb amplitude (mV) | -11.0 ± 0.5 | -18.8 ± 0.71*** | -11.4 ± 1.9### | -18.2 ± 1.4***,†† |
| Rheobase (pA) | 82.0 ± 10.7 | 156.0 ± 11.7*** | 75.0 ± 28.4# | 131.8 ± 24.0 |
| Repetitive firing | ||||
| F-I slopec (spikes/pA) | 0.05 ± 0.01 | 0.19 ± 0.02*** | 0.07 ± 0.01## | 0.14 ± 0.01 |
aResting membrane potential; bAfterhyperpolarization. One-way ANOVA followed by post hoc Bonferroni’s test. cThe number of spikes for 300 ms is divided by the intensity of the injected current (pA). ∗, ∗∗∗P < 0.05, 0.001 in comparison with pyramidal cell. #, ##, ###P < 0.05, 0.01, 0.001 in comparison with fast spiking cell. ††P < 0.01 in comparison with regular spiking cell.