Effect of mutation of α1 subunit His101 on modulation of the α1β2γ2 receptor by Ro15-1788
| α1 Subunit (no. of oocytes) | Ki (from binding studies)5-a | EC50 or IC505-b | Maximum Effect |
|---|---|---|---|
| nM | % of control | ||
| Wild type (4) | 1.29 ± 0.46 | 7.9 ± 1.95-b | Antagonist |
| H101F (4) | 5.05 ± 0.48 | 16.3 ± 2.65-b | Antagonist |
| H101Y (4) | 90 ± 10 | 147 ± 30 | 164 ± 16 |
| H101K (6) | 26.6 ± 3.9 | 37 ± 6 | 159 ± 3 |
| H101E (3) | 79.1 ± 7.0 | ||
| H101Q (4) | 8.45 ± 0.87 | 4.3 ± 1.6 | 130 ± 2 |
↵5-a Data from Davies et al. (1998), in which wild-type and mutant receptors were expressed in tsA201 cells. Kivalues were obtained in experiments in which Ro15-1788 was used to displace [3H]Ro15-4513, which was present at a concentration equivalent to its Kd value for each receptor type.
↵5-b IC50 values were obtained based on the ability of Ro15-1788 to inhibit the FNZ potentiation of GABA-induced currents in these receptors.