Table 1.
Summary of GABA and flurazepam concentration–response data from cysteine mutant and wild-type α1β2γ2 GABAAreceptors
| Receptor | GABA | Flurazepam | ||||||
|---|---|---|---|---|---|---|---|---|
| EC50(μm) | nH | n | EC50mut/EC50 αβγ | EC50(nm) | nH | n | EC50mut/EC50 αβγ | |
| αβγ | 18 ± 4.7 | 1.7 ± 0.3 | 3 | 1.0 | 250 ± 49 | 1.2 ± 0.1 | 3 | 1.0 |
| αβγY72C | 70 ± 121-160 | 1.3 ± 0.2 | 3 | 3.9 | 270 ± 64 | 1.3 ± 0.3 | 3 | 1.1 |
| αβγT73C | 20 ± 5.6 | 1.6 ± 0.3 | 3 | 1.1 | 160 ± 15 | 1.8 ± 0.3 | 3 | 0.6 |
| αβγI74C | 30 ± 4.5 | 1.2 ± 0.1 | 3 | 1.7 | 80 ± 12 | 2.9 ± 1.2 | 3 | 0.3 |
| αβγD75C | 39 ± 4.91-160 | 1.5 ± 0.3 | 3 | 2.2 | 4700 ± 13001-160 | 1.6 ± 0.6 | 3 | 18.8 |
| αβγI76C | 30 ± 13 | 1.4 ± 0.5 | 3 | 1.7 | 2600 ± 12001-160 | 2.4 ± 0.7 | 3 | 10.4 |
| αβγF77C | 24 ± 11 | 1.0 ± 0.3 | 3 | 1.3 | >10,000 | 3 | ||
| αβγF78C | 33 ± 5.8* | 1.3 ± 0.2 | 4 | 1.8 | 130 ± 35 | 1.8 ± 0.3 | 3 | 0.5 |
| αβγA79C | 30 ± 12 | 1.4 ± 0.3 | 9 | 1.7 | 310 ± 45 | 1.4 ± 0.3 | 3 | 1.2 |
| αβγQ80C | 9.0 ± 2.5 | 1.6 ± 0.4 | 3 | 0.5 | 260 ± 28 | 1.0 ± 0.1 | 3 | 1.0 |
| αβγT81C | 15 ± 1.6 | 1.5 ± 0.1 | 4 | 0.8 | 350 ± 170 | 1.5 ± 0.2 | 3 | 1.4 |
| αβγW82C | No expression | No expression | ||||||
| αβγY83C | 10 ± 1.9 | 1.6 ± 0.2 | 3 | 0.6 | 170 ± 17 | 1.1 ± 0.2 | 4 | 0.7 |
Data represent mean ± SD values. n, Number of independent experiments; nH, calculated Hill coefficient.
*
,
F1-160: Indicate values significantly different from wild-type receptors, withp < 0.05 and p < 0.01, respectively.