Inhibition by various 5-HT receptor ligands of [3H]5-CT (2 nM) binding to membranes of Sf9 cells coexpressing the h5-ht5A receptor and G protein subunits of the Gi/o and Gs family
| Proteins Expressed | pIC50 | |||||
|---|---|---|---|---|---|---|
| 5-CT | 5-HT | 5-MT | DHE | LSD | Methiothepin | |
| −logM (n) | ||||||
| h5-ht5A-HEK 2932-a | 8.28 ± 0.04 (4) | 7.40 ± 0.08 (7) | 7.17 ± 0.08 (3) | 7.15 ± 0.09 (4) | 8.40 ± 0.06 (4) | 8.26 ± 0.13 (4) |
| h5-ht5A-Sf9 | 7.72 ± 0.032-c (3) | 6.85 ± 0.082-c (7) | 6.67 ± 0.142-c (3) | 7.38 ± 0.17 (3) | 8.64 ± 0.062-c (3) | 8.44 ± 0.15 (3) |
| h5-ht5A + Gβ1γ2-Sf9 | 7.95 ± 0.092-c (3) | 6.94 ± 0.132-c (3) | 6.79 ± 0.042-c (3) | 7.41 ± 0.122-c (3) | 8.61 ± 0.16 (3) | 8.21 ± 0.27 (3) |
| h5-ht5A + Gαi/o + Gβ1γ2-Sf92-b | 8.26 ± 0.12 (3) | 7.37 ± 0.03 (3) | 7.21 ± 0.12 (3) | 6.82 ± 0.182-c (3) | 8.08 ± 0.132-c (3) | 7.19 ± 0.012-c (3) |
| h5-ht5A + Gαi1 + Gβ1γ2-Sf9 | 8.35 ± 0.09 (3) | 7.61 ± 0.28 (3) | 7.20 ± 0.15 (3) | 7.14 ± 0.08 (3) | 8.43 ± 0.14 (3) | 7.49 ± 0.292-c (3) |
| h5-ht5A + Gαi2 + Gβ1γ2-Sf9 | 8.23 ± 0.10 (3) | 7.35 ± 0.32 (3) | 7.16 ± 0.08 (3) | 7.29 ± 0.06 (3) | 8.44 ± 0.10 (3) | 7.72 ± 0.182-c (3) |
| h5-ht5A + Gαi3 + Gβ1γ2-Sf9 | 8.24 ± 0.11 (3) | 7.28 ± 0.21 (3) | 7.19 ± 0.15 (3) | 7.13 ± 0.09 (3) | 8.45 ± 0.03 (3) | 7.49 ± 0.192-c (3) |
| h5-ht5A + Gαo + Gβ1γ2-Sf9 | 8.21 ± 0.12 (3) | 7.28 ± 0.17 (3) | 6.99 ± 0.09 (3) | 7.18 ± 0.04 (3) | 8.17 ± 0.092-c (3) | 7.83 ± 0.112-c (3) |
| h5-ht5A + Gαz + Gβ1γ2-Sf9 | 8.01 ± 0.072-c (3) | 7.14 ± 0.182-c (3) | 6.81 ± 0.052-c (3) | 7.29 ± 0.19 (3) | 8.37 ± 0.07 (3) | 8.07 ± 0.11 (3) |
| h5-ht5A + Gαs-s + Gβ1γ2-Sf9 | 8.09 ± 0.032-c (3) | 7.10 ± 0.042-c (3) | 6.88 ± 0.042-c (3) | 7.02 ± 0.50 (3) | 8.51 ± 0.08 (3) | 8.37 ± 0.07 (3) |
Radioligand binding studies were performed as described inExperimental Procedures, and pIC50 (−logM) values were derived from individual curves. Results are mean pIC50 ± S.D. values from n independent experiments.