Table 4

Single-channel properties of native, WT, and mutant AChRs

Property	BC₃H1	WT	10′αβ	6′αδ
Single-channel current (pA)	−4.0 ± 0.2	−4.0 ± 0.3	−4.0 ± 0.2	−3.9 ± 0.2
Brief burst duration (ms)	0.23 ± 0.13	0.20 ± 0.10	0.18 ± 0.04	0.38 ± 0.10^4-a
Fraction of brief bursts	0.30 ± 0.15	0.37 ± 0.17	0.49 ± 0.16	0.34 ± 0.08
Long burst duration (ms)	4.6 ± 1.4	5.9 ± 0.9	7.4 ± 3.2	13.5 ± 6.8^4-a
Brief closed duration (ms)	0.09 ± 0.05	0.11 ± 0.05	0.54 ± 0.24^4-a	0.20 ± 0.10^4-b

Results are presented as mean ± S.D. for nine patches of WT, ten patches of 10′αβ, and seven patches of 6′αδ (all expressed in HEK-293 cells). Data for receptors in BC₃H1 cells are fromDilger et al., 1992, except for the brief long burst durations, which were not previously published (but are based on the same experiments with 20 patches) 0.2 μM ACh, −100 mV.

↵4-a Significantly different from WT, t test, p < 0.01.
↵4-b Significantly different from WT, t test, p < 0.05.