TABLE 2.
Firing and action potential properties of type I and II nucleus incertus neurons.
| Parameter | Type I (n) | Type II (n) | Statistics | ||
| Firing properties | |||||
| Spontaneous firing rate (Hz) | 2.38 ± 1.64 (36) | 3.70 ± 3.944 (34) | † p = 0.006 | ||
| Interspike interval (s) | 0.44 ± 0.27 (35) | 0.24 ± 0.11 (28) | # p = 0.0002 | ||
| CV of interspike interval | 0.12 ± 0.14 (37) | 0.15 ± 0.28 (34) | † p = 0.028 | ||
| Threshold (mV) | −43.98 ± 7.32 (130) | −48.09 ± 3.95 (78) | † p < 0.0001 | ||
| Rheobase (nA) | 0.13 ± 0.05 (110) | 0.06 ± 0.01 (52) | § p < 0.0001 | ||
| Time to first AP (ms) | 152.9 ± 127.8 (191) | 18.79 ± 7 (100) | † p < 0.0001 | ||
| Neuronal gain | 0.08 ± 0.003 (123) | 0.14 ± 0.005 (69) | Comparison of slopes: F = 129.806 DFn = 1 DFd = 2337, p < 0.0001 | ||
| Regular firing | 36/37 | 26/36 | Fisher’s exact test, p = 0.0031 | ||
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| Membrane properties | |||||
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| Resting membrane potential (mV) | −59.04 ± 3.52 (20) | −52.64 ± 5.757 (20) | # p = 0.0002 | ||
| Resistance (MOhm) | 791.9 ± 426.5 (96) | 789.1 ± 391.3 (53) | †p = 0.618 | ||
| Time constant (ms) | 56.38 ± 29.18 (96) | 40.51 ± 31.18 (53) | † p = 0.0002 | ||
| Capacity (pF) | 72.07 ± 29.6 (94) | 57.58 ± 21.61 (53) | † p < 0.0001 | ||
| Sag amplitude (mV) | −3.97 ± 3.72 (32) | −2.52 ± 2.40 (17) | † p = 0.038 | ||
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| Single AP properties | |||||
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| Threshold (mV) | −39.18 ± 5.25 (48) | −39.6 ± 5.44 (38) | § p = 0.714 | ||
| 10–90 rise (us) | 295.6 ± 62.2 (48) | 301.8 ± 89.8 (38) | †p = 0.617 | ||
| Amplitude (mV) | 55.37 ± 19.57 (48) | 51.92 ± 15.94 (38) | † p = 0.02 | ||
| Half-width (us) | 699.2 ± 104.1 (48) | 654.7 ± 137.8 (38) | § p = 0.092 | ||
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| AHP properties | |||||
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| medium AHP | fast AHP | medium AHP | m AHP only | ||
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| AHP trough (mV) | −88.0 ± 2.73 (48) | −65.0 ± 2.9 (18) | −77.1 ± 1.96 (17) | −79.02 ± 4.26 (20) | One way ANOVA: p < 0.0001
F(3,99) = 266.9; Tukey’s multiple comparisons: I mAHP vs. II fAHP p ≤ 0.0001 I mAHP vs. II mAHP p ≤ 0.0001 I mAHP vs. II mAHP only p ≤ 0.0001 II fAHP vs. II mAHP p ≤ 0.0001 II fAHP vs. II mAHP only p ≤ 0.0001 II mAHP vs. II mAHP only ns |
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| Medium AHP | Fast AHP | Medium AHP | m AHP only | ||
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| Peak—AHP time (ms) | 9.136 ± 3.08 (45) | 2.51 ± 1.48 (18) | 65.7 ± 42.93 (18) | 42.69 ± 34.4 (20) | Kruskal—Wallis test: p < 0.0001; Dunn’s multiple comparisons: I mAHP vs. II fAHP p ≤ 0.001 I mAHP vs. II mAHP p ≤ 0.0001 I mAHP vs. II mAHP only p ≤ 0.0001 II fAHP vs. II mAHP p ≤ 0.0001 II fAHP vs. II mAHP only p ≤ 0.0001 II mAHP vs. II mAHP only ns |
Bold values denote statistical significance at the p < 0.05 level. †Unpaired Mann–Whitney test; #Unpaired t-test with Welch’s correction; §Unpaired t-test.