Table 2.
Parameters of I GABA enhancement of wild‐type α1β3γ2S and mutant GABAA receptors by VA
| Subunit composition | Emax (%) | EC50 (μM) | n H | n |
|---|---|---|---|---|
| α1β3γ2S | 632 ± 88 | 20.2 ± 5.2 | 1.50 ± 0.29 | 9 |
| α1I227Aβ3γ2S | 776 ± 60 | 40.8 ± 8.4 | 1.13 ± 0.08 | 6 |
| α1L231Aβ3γ2S | 703 ± 82 | 18.8 ± 4.4 | 1.37 ± 0.18 | 5 |
| α1M235Aβ3γ2S | 546 ± 28 | 21.1 ± 2.8 | 1.19 ± 0.08 | 6 |
| α1M235Wβ3γ2S | 193 ± 16 *** | 24.3 ± 7.7 | 1.37 ± 0.34 | 6 |
| α1L268Aβ3γ2S | 582 ± 80 | 19.9 ± 5.6 | 1.06 ± 0.13 | 5 |
| α1β3T262Aγ2S | 573 ± 96 | 2.5 ± 0.8 | 1.00 ± 0.16 | 5 |
| α1β3T262Sγ2S | 578 ± 42 | 3.4 ± 0.7 | 0.85 ± 0.15 | 9 |
| α1β3N265Sγ2S | 134 ± 32 *** | 142.9 ± 67.5 *** | 1.33 ± 0.39 | 7 |
| α1β3T266Aγ2S | 666 ± 55 | 7.5 ± 1.5 | 1.26 ± 0.1 | 12 |
| α1β3R269Aγ2S | 259 ± 22 *** | 84.1 ± 14.7 | 1.63 ± 0.19 | 7 |
| α1β3M286Aγ2S | 283 ± 52 *** | 60.1 ± 18.5 | 1.47 ± 0.21 | 6 |
| α1β3M286Wγ2S | 67 ± 35 *** | n.d. | n.d. | 10 |
| α1β3F289Sγ2S | 222 ± 12 *** | 180.6 ± 21.6 *** | 1.20 ± 0.07 | 8 |
Maximal efficacies (Emax, %), EC50 concentrations (μM) and Hill coefficients (n H) are given for each receptor as mean ± SEM for n number of cells tested. Statistical significance of difference from wild‐type was calculated using a one‐way ANOVA followed by Dunnett's mean comparison test. n.d., non‐determined. *** P < 0.001.