Table 2

Electrophysiological properties of sampled pyramidal neurons

	Pyramidal neurons
	Layer 2/3	Layer 4	Layer 5a	Layer 5b	Layer 6 CTL	Layer 6 CCL
Resting membrane potential (mV)	-77.4 ± 6.2	-70.7 ± 7.0	-63.7 ± 8.3	-71.7 ± 9.5	-63.7 ± 6.6*	-72.2 ± 5.2
Membrane time constant (ms)	9.9 ± 1.4	14.3 ± 6.2	17.5 ± 0.5	10.3 ± 1.9	10.0 ± 4.1	7.4 ± 10.0
Input resistance (MΩ)	73.0 ± 16.4	121.4 ± 39.9	119.9 ± 38.9	63.4 ± 11.9	111.5 ± 28.5	81.3 ± 11.4
Action potential (AP) threshold (mV)	-44.7 ± 1.5	-47.5 ± 2.4	-46.1 ± 3.8	-52.8 ± 4.1	-50.3 ± 2.0	-47.2 ± 9.4
AP height (mm)^a	111.9 ± 11.1	101.4 ± 10.3	90.7 ± 12.6*	99.5 ± 6.0	84.8 ± 3.2**	108.5 ± 7.6^¶¶
AP half width (ms)	1.04 ± 0.32	1.20 ± 0.23	1.03 ± 0.11	0.76 ± 0.01	0.68 ± 0.12^†	0.98 ± 0.20
Fast afterpotential (mV)^b	2.7 ± 3.1	6.4 ± 5.8	-0.8 ± 3.3	1.7 ± 4.4	-6.1 ± 2.0^†	8.3 ± 6.6^¶¶
Slow afterpotential (mV)^b	-0.8 ± 1.5	2.0 ± 3.4	-3.5 ± 1.0	-2.0 ± 2.3	-2.1 ± 2.1	0.7 ± 3.4

*,^†,^‡,^§,^¶Significant differences (*,^†,^‡,^§,^¶ p < 0.05; **,^††,^‡‡,^§§,^¶¶ p < 0.01; ***,^†††,^‡‡‡,^§§§,^¶¶¶ p < 0.001; ****,^††††,^‡‡‡‡,^§§§§,^¶¶¶¶ p < 0.0001 by one-way-ANOVA and Tukey's multiple comparison test) from the value of layer 2/3, layer 4, layer 5a, layer 5b, or layer 6 CT-like (CTL) neurons, respectively.
^aAP height was measured form resting membrane potential.
^bFast and slow afterpotential was measured from baseline prior to action potential evoked by a short (<5 ms) depolarizing pulse, at 3.3 ms or 29 ms from action potential onset, respectively. Pulse response without action potential to the same depolarizing pulse was recorded in another trace and subtracted. Our previous study showed that one type of layer 6 pyramidal neurons has a peak of fast afterhyperpolarization (AHP) at 3.3 ms on average, and that another type of layer 6 pyramidal neurons lacks fast AHP and has a peak of medium-range AHP at 29 ms on average (Kaneko et al., 1995).