Table 2.

Statistical analysis of electrophysiological parameters in wild-type and Kv4.3−/− SNc DA neurons

ParameterMean/medianSD/IQRnMean/medianSD/IQRnp value (t test)
Passive properties
Rm (MΩ)386.00202.0097422.00147.00720.2351
ISI (ms)669.50334.5084304.00118.00732.2 × 10–16***
CVISI (%)5.764.45843.843.31734 × 10–4***
Postinhibitory rebound
Voltage sag (mV)31.704.2910132.503.95770.2082
Rebound delay (ms)256.00199.009729.0018.00772.2 × 10–16***
Action potential
AP threshold (mV)–42.905.80101–41.604.00770.15
AP amplitude (mV)65.297.8410166.016.27770.5024
AP half-width (ms)1.290.241011.400.33770.038*
AP rise slope (mV/ms)86.4724.9510187.8924.61770.7049
AP decay slope (mV/ms)–47.718.73101–45.338.89770.0756
AHP trough Vm (mV)–73.844.58101–73.833.58770.9892
AHP latency (ms)55.5638.2810153.7628.68770.84
Start frequency 100 pA (Hz)7.233.989810.683.73774 × 10–8***
Gain start (Hz/100 pA)8.754.189710.274.11771.7 × 10–3**
Gain end (Hz/100 pA)3.411.61763.111.69660.37
SFA index2.731.94763.241.54660.012*
V50 inactivation (mV)–68.915.1087–73.313.84394.3 × 10–6***
Inactivation tau (ms)30.9027.158312.906.72427.1 × 10–12***
Amplitude (nA)2.142.79870.930.64391.8 × 10–12***
Charge (pA.s)152.80177.808319.4022.40376.4 × 10–15***
Charge density (pA.s/pF)1.171.00820.180.20366.4 × 10–13***
V50 activation (mV)–88.414.2475–88.423.81550.9886
Amplitude (pA)453.00212.5075575.30275.80576 × 10–4***
Amplitude density (pA/pF)3.491.93745.762.36547.6 × 10–11***
  • The values for 16 electrophysiological parameters measured under current-clamp (corresponding to passive properties, spontaneous activity, postinhibitory rebound, action potential, and excitability) and eight electrophysiological parameters measured under voltage-clamp (corresponding to IA and IH properties) are presented for WT and Kv4.3−/− SNc DA neurons. Mean and SD (black text) are reported for normally-distributed data, while median and interquartile range (IQR) are reported otherwise (italic text). Accordingly, statistical differences between WT and Kv4.3−/− neurons were tested using a t test or a Mann–Whitney test, depending on the normality of the data. Asterisks indicate statistically significant differences (*p < 0.05, **p < 0.01, ***p < 0.001).