Table 2.

Membrane properties and spike features in pyramidal cells of layer 2/3 visual cortex

	Three to four weeks			Six to eight weeks
	WT	KO	Statistical value	WT	KO	Statistical value
Input resistance (MΩ)	91.51 ± 4.96	104.33 ± 13.07	t₍₂₃₎ = 1.125 p = 0.2721	75.49 ± 6.19	82.32 ± 5.57	t₍₂₂₎ = 0.8119 p = 0.4255
V_spike peak (mV)	46.41 ± 1.17	42.93 ± 2.65	t₍₂₃₎ = 1.407 p = 0.1727	48.54 ± 1.65	46.75 ± 1.34	t₍₂₂₎ = 0.8498 p = 0.4046
V_trough (mV)	−47.87 ± 0.44	−49.13 ± 0.94	t₍₂₃₎ = 1.388 p = 0.1785	−48.08 ± 0.59	−48.46 ± 0.62	t₍₂₂₎ = 0.4247 p = 0.6752
Spike height (mV)	94.28 ± 1.41	92.06 ± 3.15	t₍₂₃₎ = 0.7528 p = 0.4592	96.63 ± 1.97	95.21 ± 1.62	p = 0.5036*
Spike width (ms)	1.18 ± 0.04	1.22 ± 0.05	t₍₂₃₎ = 0.5595 p = 0.5812	1.05 ± 0.06	0.92 ± 0.03	t₍₂₂₎ = 2.069 p = 0.0505
V_threshold (mV)	−37.25 ± 0.56	−38.67 ± 0.90	t₍₂₃₎ = 1.401 p = 0.1747	−38.20 ± 1.02	−39.14 ± 0.58	t₍₂₂₎ = 0.8592 p = 0.3995
Upstroke (mV/ms)	265.83 ± 8.82	250.42 ± 18.31	t₍₂₃₎ = 0.8626 p = 0.3973	349.53 ± 17.73	358.53 ± 12.56	p = 0.9431*
Downstroke (mV/ms)	−68.02 ± 2.31	−65.86 ± 3.44	t₍₂₃₎ = 0.5238 p = 0.6054	−79.90 ± 4.59	−91.96 ± 3.79	t₍₂₂₎ = 2.033 p = 0.0543
Upstroke/downstroke ratio	−3.93 ± 0.11	−3.79 ± 0.18	t₍₂₃₎ = 0.7090 p = 0.4854	−4.45 ± 0.26	−3.93 ± 0.11	t₍₂₂₎ = 2.088p = 0.0486
RMP (mV)	−68.40 ± 0.81	−67.01 ± 1.71	p = 0.6659*	−70.27 ± 1.10	−69.72 ± 0.83	t₍₂₂₎ = 0.4048 p = 0.6895
First ISI (ms)	6.95 ± 0.26	7.86 ± 1.47	t₍₂₃₎ = 0.8638 p = 0.3966	6.41 ± 0.46	5.26 ± 0.58	p = 0.0220*
Mean ISI (ms)	26.99 ± 0.76	28.63 ± 2.24	p = 0.7504*	29.41 ± 1.43	26.41 ± 1.44	t₍₂₂₎ = 1.436 p = 0.1650
Adaptation index	0.02 ± 0.001	0.02 ± 0.001	t₍₂₃₎ = 0.6344 p = 0.5321	0.02 ± 0.004	0.03 ± 0.002	p = 0.7879*
Slope of current-firing curve	7.02 ± 0.23	6.41 ± 0.60	p = 0.0883*	6.35 ± 0.28	7.19 ± 0.47	p = 0.1583*

Spike features were obtained from the first action potential evoked by the step current which was just above the threshold. ISIs were obtained from the response evoked by the step current which was 360 pA above the threshold. Two-tailed unpaired t test or M–W test (*) was used for statistical analyses. Bold text indicates statistical significance, p < 0.05.