Ki values of OPC-28326 and yohimbine determined by ligand binding assay with [3H]RX821002 (n = 3) and by luciferase assay with epinephrine (n = 5, mean ± S.D.), using the CHO cells overexpressing rat α2D-adrenoceptors, α2B-adrenoceptors, or α2C-adrenoceptors
| Ki | α2D | α2B | α2C |
|---|---|---|---|
| nM | |||
| Radioligand Binding Assay | |||
| Yohimbine | 59.0 ± 6.5 | 16.8 ± 1.4 | 10.6 ± 1.4 |
| OPC-28326 | 3840 ± 887 | 663 ± 46 | 13.7 ± 1.9 |
| Luciferase Assay | |||
| Yohimbine | 12.9 ± 1.8 | 7.2 ± 1.6 | 2.7 ± 1.7 |
| OPC-28326 | 1059 ± 337 | 240 ± 29 | 7.8 ± 1.2 |