Table 2.
Analyses of open and burst durations for wild-type and mutant AChRs in HEK cells
| AChR | Open Intervals | Bursts | ||||
|---|---|---|---|---|---|---|
| T1,ms (a1) |
T2, ms (a2) |
T3, ms (a3) |
T1,ms (a1) |
T2, ms (a2) |
T3, ms (a3) |
|
| Wild type | 0.037 ± 0.033a | 0.31 ± 0.050 | 1.35 ± 0.051 | 0.036 ± 0.0017b | 0.47 ± 0.059 | 3.31 ± 0.12 |
| (0.17 ± 0.022) | (0.27 ± 0.038) | (0.67 ± 0.042) | (0.24 ± 0.021) | (0.21 ± 0.027) | (0.58 ± 0.038) | |
| βP248L | 0.12 ± 0.014 | 0.88 ± 0.014 | 0.14 ± 0.019c | 1.24 ± 0.026 | ||
| (0.23 ± 0.035) | (0.77 ± 0.035) | (0.21 ± 0.013) | (0.86 ± 0.069) | |||
| αT237L | 1.59 ± 0.12 | 4.50 ± 0.27 | ||||
| (1.00± 0.00) | (1.00± 0.00) | |||||
| δA251L | 0.21 ± 0.065c | 0.85 ± 0.17 | 0.29 ± 0.091c | 1.11 ± 0.15 | ||
| (0.24 ± 0.066) | (0.84 ± 0.088) | (0.30 ± 0.083) | (0.80 ± 0.11) | |||
| εA246L | 1.35 ± 0.066 | 0.30 ± 0.00d | 3.27 ± 0.18 | |||
| (1.00± 0.00) | (0.26± 0.00) | (0.91 ± 0.86) | ||||
| αT237P | 2.02 ± 0.050 | 8.70 ± 1.20 | ||||
| (1.00± 0.00) | (1.00± 0.00) | |||||
| δA251P | 1.67 ± 0.048 | 4.55 ± 0.50 | ||||
| (1.00 ± 0.00) | (1.00 ± 0.00) | |||||
| εA246P | 1.26 ± 0.11 | 0.30 ± 0.024 | 3.33 ± 0.11 | |||
| (1.00 ± 0..00) | (0.15± 0.036) | (0.86 ± 0.036) | ||||
| βP248T | 1.05 ± 0.10 | 0.15 ± 0.084 | 2.26 ± 0.11 | |||
| (1.00 ± 0.00) | (0.17 ± 0.035) | (0.83 ± 0.035) | ||||
| βP248A | 0.051 ± 0.0012c | 0.68 ± 0.079 | 0.38 ± 0.10 | 1.68 ± 0.21 | ||
| (0.18 ± 0.098) | (0.88 ± 0.081) | (0.52 ± 0.15) | (0.48 ± 0.15) | |||
| βP248G | 0.61 ± 0.088 | 0.28 ± 0.067 | 1.54 ± 0.098 | |||
| (1.00 ± 0.00) | (0.44 ± 0.14) | (0.56 ± 0.14) | ||||
Values indicate mean ± SE from 21 patches for wild-type, 3 patches for all mutants except for αT237L with 5 patches. [ACh] = 50 nM for wild-type, δA251L, εA246L, βP248A, and βP248G; 1 μM for others. Final bandwidth 10–12 kHz. MP = −80 mV. τn and an are time constants and fractional areas.
a,b,c,d
corresponding component of open and burst durations were not detected for 12, 3, 1, and 2 patches, respectively.