Agonist binding affinities of neuronal nAChRs
| Ligand | α2β2 | α2β4 | α3β2 | α3β4 | α4β2 | α4β4 | |
|---|---|---|---|---|---|---|---|
| K d app (pm) (n H) | [3H]Epibatidine | 10.3 ± 1.1 | 86.8 ± 9.4 | 13.6 ± 1.9 | 303.0 ± 44 | 30.0 ± 3.9 | 84.7 ± 6.7 |
| (1.13 ± 0.20) | (1.17 ± 0.08) | (1.21 ± 0.10) | (1.18 ± 0.04) | (1.07 ± 0.06) | (0.91 ± 0.06) | ||
| K i app (nm) (n H) | Acetylcholine | 1.8 ± 0.51 | 110 ± 20 | 29.0 ± 1.9 | 560 ± 72 | 34 ± 6.6 | 72 ± 9.2 |
| (0.67 ± 0.13) | (0.64 ± 0.08) | (0.92 ± 0.05) | (0.96 ± 0.11) | (1.1 ± 0.21) | (0.85 ± 0.09) | ||
| Anabasine | 14 ± 1.1 | 450 ± 32 | 57 ± 14 | 2100 ± 480 | 76 ± 3.6 | 370 ± 22 | |
| (0.79 ± 0.05) | (0.96 ± 0.06) | (0.92 ± 0.17) | (0.79 ± 0.12) | (1.04 ± 0.05) | (0.90 ± 0.05) | ||
| Cytisine | 0.38 ± .02 | 4.9 ± 1.1 | 14 ± 1.6 | 56 ± 7.3 | 0.99 ± 0.07 | 1.2 ± 0.08 | |
| (1.2 ± 0.08) | (0.71 ± 0.11) | (1.04 ± 0.11) | (0.77 ± 0.07) | (1.1 ± 0.07) | (.96 ± 0.06) | ||
| DMPP | 10 ± 0.58 | 1200 ± 130 | 18 ± 1.0 | 1300 ± 210 | 48 ± 1.8 | 1000 ± 75 | |
| (0.87 ± 0.04) | (0.99 ± 0.09) | (0.98 ± 0.05) | (0.78 ± 0.10) | (1.03 ± 0.04) | (0.90 ± 0.05) | ||
| Lobeline | 2.6 ± 0.24 | 220 ± 33 | 13 ± 1.3 | 480 ± 56 | 4.0 ± 0.63 | 49 ± 5.3 | |
| (0.88 ± 0.07) | (1.1 ± 0.17) | (0.68 ± 0.05) | (0.60 ± 0.05) | (0.68 ± 0.06) | (0.75 ± 0.06) | ||
| Nicotine | 0.81 ± .08 | 70 ± 4.2 | 16 ± 0.52 | 300 ± 110 | 4.6 ± 0.33 | 26 ± 2.4 | |
| (0.88 ± 0.07) | (0.98 ± 0.06) | (1.0 ± 0.03) | (0.74 ± 0.18) | (0.87 ± 0.05) | (1.0 ± 0.09) |
K d app values for [3H]epibatidine were taken from the fit data in Fig. 3.K i app values for acetylcholine, anabasine, cytisine, DMPP, lobeline, and nicotine were calculated from the IC50 values taken from the fit data in Fig. 4 (see Experimental Procedures).