Ligand affinities for the H4 receptor
| −LogEC50(Ki) | Hill Coefficient | |
|---|---|---|
| nM | ||
| Amitriptyline | 7.31 ± 0.26 (33.6) | 0.8 |
| Chlorpromazine | 7.13 ± 0.29 (50.2) | 0.7 |
| Doxepin | 6.79 ± 0.13 (105.9) | 0.6 |
| Cinnarizine | 6.73 ± 0.20 (141.6) | 0.7 |
| Promethazine | 6.71 ± 0.19 (150.2) | 0.6 |
| Cyproheptadine | 6.53 ± 0.09 (201.5) | 0.9 |
| Clemizole | 6.16 ± 0.12 (402.2) | 0.5 |
| Mianserin | 5.96 ± 0.40 (750.0) | 0.9 |
| Clozapine | 5.90 ± 0.22 (849.6) | 1.2 |
| Chlorpheniramine | 5.39 ± 0.16 (2910.0) | 1.1 |
| Histamine | 5.30 ± 0.04 (3442.3) | 0.5 |
| Imetit | 5.25 ± 0.44 (3795.6) | 0.2 |
| Pheniramine | 5.21 ± 0.47 (4184.0) | 0.2 |
| Dimaprit | 4.76 ± 0.19 (11812.7) | 0.4 |
| α-Methylhistamine | >10,000 | Undetermined |
| Cimetidine | >10,000 | Undetermined |
Data represent mean ± S.E. for two to four separate experiments. Twelve different concentrations spanning 6 log units of test drug were used to displace 15 nM [3H]pyrilamine.