Efficacies (Emax values) and potencies (pEC50 values) of antiparkinson agents at recombinant h5-HT1A, h5-HT1B, and h5-HT1D receptors
| Ligand | h5-HT1A | h5-HT1B | h5-HT1D | |||
|---|---|---|---|---|---|---|
| Emax | pEC50 | Emax | pEC50 | Emax | pEC50 | |
| Apomorphine | 35 ± 7 | 5.92 | 0 | <5 | 0 | <5 |
| Bromocriptine | 72 ± 11 | 7.24 | 66 ± 7 | 5.96 | 86 ± 10 | 7.07 |
| Cabergoline | 93 ± 3 | 6.43 | 102 ± 9 | 5.65 | 68 ± 10 | 7.80 |
| Lisuride | 98 ± 1 | 8.90 | 85 ± 7 | 7.58 | 81 ± 7 | 8.49 |
| Pergolide | 63 ± 8 | 6.95 | 90 ± 15 | 5.96 | 86 ± 7 | 7.46 |
| Piribedil | 80 ± 14 | 5.17 | N.D. | N.D. | N.D. | N.D. |
| Roxindole1-a | 60 ± 1 | 8.28 | 27 ± 2 | 5.83 | 14 ± 6 | 7.80 |
| Terguride | 71 ± 3 | 7.24 | 37 ± 3 | 6.37 | 62 ± 7 | 7.85 |
Efficacy (Emax) and potency (pEC50) values at h5-HT1A, h5-HT1B and h5-HT1D receptors were determined by [35S]GTPγS binding. Emaxvalues are percentages of the stimulation observed with a maximally efficacious concentration of serotonin (10 μM) and are expressed as means ± S.E.M. values of at least three independent determinations performed in triplicate. pEC50 values are the means of at least three independent determinations with S.E.M. values of less than 0.2 log units. Serotonin exhibited pEC50 values of 7.70, 8.06, and 8.89 at h5-HT1A, h5-HT1B, and h5-HT1D receptors, respectively.
N.D., not determined (pKi < 5.0).
↵1-a Newman-Tancredi et al., 1999.