Affinities of muscarinic agonists for the M1-M4subtypes of muscarinic receptors expressed in membranes of CHO cells
| M1 | M2 | M3 | M4 | |||||
|---|---|---|---|---|---|---|---|---|
| pKi | nH | pKi | nH | pKi | nH | pKi | nH | |
| Arecaidine propargyl ester | 6.35 ± 0.08 | 0.97 ± 0.03 | 5.71 ± 0.08 | 0.99 ± 0.01 | 5.72 ± 0.12 | 0.96 ± 0.04 | 5.93 ± 0.11 | 0.98 ± 0.01 |
| Arecoline | 5.73 ± 0.13 | 0.96 ± 0.02 | 5.24 ± 0.10 | 0.96 ± 0.02 | 5.42 ± 0.03 | 0.97 ± 0.03 | 5.45 ± 0.05 | 0.98 ± 0.03 |
| Acetylcholine | 4.32 ± 0.07 | 0.99 ± 0.04 | 4.33 ± 0.09 | 0.99 ± 0.01 | 4.54 ± 0.08 | 0.97 ± 0.00 | 4.49 ± 0.08 | 0.97 ± 0.01 |
| Bethanechol | 4.01 ± 0.11 | 0.99 ± 0.05 | 4.04 ± 0.10 | 0.97 ± 0.02 | 4.15 ± 0.07 | 0.97 ± 0.05 | 4.03 ± 0.05 | 0.96 ± 0.02 |
| Carbachol | 4.46 ± 0.11 | 0.97 ± 0.05 | 4.19 ± 0.08 | 0.97 ± 0.02 | 4.42 ± 0.06 | 0.98 ± 0.03 | 4.29 ± 0.09 | 0.96 ± 0.04 |
| Furmethide | 4.11 ± 0.11 | 0.97 ± 0.03 | 4.53 ± 0.06 | 0.96 ± 0.04 | 4.11 ± 0.08 | 0.97 ± 0.02 | 4.27 ± 0.15 | 0.96 ± 0.02 |
| Methylfurmethide | 4.55 ± 0.07 | 0.97 ± 0.04 | 4.93 ± 0.1 | 0.96 ± 0.05 | 4.59 ± 0.11 | 0.95 ± 0.04 | 4.71 ± 0.03 | 0.97 ± 0.02 |
| McN-A-343 | 5.1 ± 0.18 | 0.98 ± 0.02 | 4.77 ± 0.05 | 0.96 ± 0.02 | 5.06 ± 0.07 | 0.97 ± 0.04 | 4.96 ± 0.08 | 0.97 ± 0.03 |
| Oxotremorine | 5.48 ± 0.16 | 0.96 ± 0.04 | 5.03 ± 0.11 | 0.97 ± 0.05 | 5.28 ± 0.07 | 0.98 ± 0.02 | 5.15 ± 0.08 | 0.96 ± 0.03 |
| Oxotremorine-M | 5.09 ± 0.13 | 0.98 ± 0.03 | 4.92 ± 0.09 | 0.96 ± 0.04 | 5.14 ± 0.01 | 0.99 ± 0.02 | 5.19 ± 0.15 | 0.97 ± 0.02 |
| Pilocarpine | 5.14 ± 0.11 | 0.98 ± 0.05 | 4.92 ± 0.04 | 0.96 ± 0.01 | 5.09 ± 0.04 | 0.99 ± 0.03 | 5.22 ± 0.19 | 0.97 ± 0.01 |
| Pentylthio-TZTP | 8.62 ± 0.13 | 0.96 ± 0.04 | 7.89 ± 0.11 | 0.99 ± 0.05 | 8.09 ± 0.09 | 0.97 ± 0.01 | 8.70 ± 0.39 | 0.97 ± 0.01 |
Data were obtained from measurements of the binding competition between the agonists and [3H]NMS in the presence of 0.5 mm GTP. Data are mean ± standard error of three experiments with triplicate incubations.