Comparison of the intrinsic efficacy profiles of α5IA, DMCM, FG 7142, and diazepam
Values shown are mean ± S.E.M. of four to nine separate determinations.
| Human Recombinant GABAA Receptors Containing β3, γ2 Plus | |||||
|---|---|---|---|---|---|
| α1 | α2 | α3 | α5 | ||
| α5IA | % modulationa | -18 ± 3 | +13 ± 3 | -7 ± 4 | -40 ± 1 |
| EC50, nMb | N.C. | N.C. | N.C. | 2.2 ± 0.2 | |
| DMCM | % modulation | -71 ± 1 | -53 ± 3 | -62 ± 2 | -57 ± 1 |
| EC50, nM | 3.9 | 3.7 | 2.4 | 1.2 | |
| FG 7142 | % modulation | -47 ± 2 | -38 ± 6 | -40 ± 5 | -35 ± 4 |
| EC50, nM | 137 | 5.7 | 1020 | 1439 | |
| Diazepam | % modulation | 103 ± 14 | 135 ± 11 | 118 ± 28 | 106 ± 3 |
| EC50, nM | 27 | 19 | 48 | 17 | |
N.C., not calculated because of small responses producing poorly defined concentration-effect curves.
↵ a Values for % modulation are the maximum effects of compound on the current produced by an EC20-equivalent concentration of GABA with negative and positive values representing an attenuation (inverse agonism) or potentiation (agonism), respectively.
↵ b The EC50 represents the concentration at which compound produces an effect that is 50% of the maximum at that particular subtype.