Table 1.

Membrane properties of striatal fast-spiking GABAergic interneurons, cholinergic interneurons and medium spiny neurons (MSNs)

	Fast-spiking GABAergic interneurons (n = 45), a	Cholinergic interneurons (n = 65), b	MSNs (n = 50), c	a vs. b	a vs. c	b vs. c
Passive membrane properties
RMP (mV)	−72.8 ± 0.7	−61.9 ± 0.4	−75.3 ± 0.9	< 0.001	< 0.05	< 0.001
Ri (MΩ)	209.7 ± 7.4	307.3 ± 16.9	225.7 ± 12.9	< 0.001	n.s.	< 0.001
Action potential properties
AP threshold (mV)	−30.2 ± 1.0	−41.6 ± 0.9	−37.4 ± 0.5	< 0.001	< 0.001	< 0.001
Rheobase (pA)	161.9 ± 9.0	40.1 ± 3.1	163.6 ± 8.8	< 0.001	n.s.	< 0.001
Delay to first spike (ms)	248.5 ± 16.0	281.0 ± 13.2	414.6 ± 4.3	n.s.	< 0.001	< 0.001
AP amplitude (mV)	46.3 ± 1.0	61.3 ± 1.0	68.5 ± 1.3	< 0.001	< 0.001	< 0.001
AP duration (ms)	1.4 ± 0.1	5.2 ± 0.2	3.3 ± 0.2	< 0.001	< 0.001	< 0.001
fAHP peak amplitude (mV)	12.8 ± 0.4	12.0 ± 0.3	8.6 ± 0.3	n.s.	< 0.001	< 0.001
fAHP time to peak (ms)	1.84 ± 0.15	25.7 ± 1.5	16.1 ± 0.6	< 0.001	< 0.001	< 0.001
sAHP duration (ms)	17.9 ± 0.8	64.6 ± 2.9	38.3 ± 1.3	< 0.001	< 0.001	< 0.001
AP rise/AP decay	1.43 ± 0.13	4.22 ± 0.31	2.63 ± 0.13	< 0.001	< 0.001	< 0.001
Action potential trains
Initial firing rate (Hz)	34.4 ± 2.0	9.4 ± 0.5	12.5 ± 0.4	< 0.001	< 0.001	< 0.001
Final firing rate (Hz)	22.2 ± 1.7	8.0 ± 0.4	13.0 ± 0.4	< 0.001	< 0.001	< 0.001
SFA ratio	2.0 ± 0.2	1.2 ± 0.1	0.96 ± 0.02	< 0.001	< 0.001	< 0.001

RMP, resting membrane potential; R_i, input resistance; AP, action potential; AHP, afterhyperpolarization (f, fast; s, slow); SFA, spike frequency adaptation. The AP characteristics were measured when injecting a current of 30 pA above AP threshold. AP rise/AP decay is the ratio of AP rise (dV/dt; mV ms⁻¹) and AP decay (dV/dt; mV ms⁻¹). P < 0.001, extremely significant; P < 0.01, very significant; P < 0.05, significant; n.s., not significant.