Table 4.
Human β-arrestin-2 translocation to CB1 and CB2.
| hβ-Arrestin-2 |
||||||||
|---|---|---|---|---|---|---|---|---|
| CB1 |
CB1 + GRK2 |
CB2 |
CB2 + GRK2 |
|||||
| logEC50 ± SEM (M) | Emax ± SEM (ΔBRET.sec) | logEC50 ± SEM (M) | Emax ± SEM (ΔBRET.sec) | logEC50 ± SEM (M) | Emax ± SEM (ΔBRET.sec) | logEC50 ± SEM (M) | Emax ± SEM (ΔBRET.sec) | |
| CP55,940 | –7.81 ± 0.13 | 83.7 ± 8.6 | –8.53 ± 0.03Δ | 120.0 ± 12.5 | –8.70 ± 0.12§ | 37.4 ± 6.2 | –8.71 ± 0.06 | 70.4 ± 7.1Δ |
| 2-AG | –5.35 ± 0.09 | 235.6 ± 17.9 | –5.69 ± 0.10Δ | 149.9 ± 17.6Δ | –5.73 ± 0.17 | 31.3 ± 3.9 | –5.68 ± 0.16 | 68.7 ± 2.5Δ |
| WIN55,212-2 | –6.60 ± 0.13§ | 164.2 ± 19.9 | X | X | –8.56 ± 0.20§ | 24.4 ± 1.4 | X | X |
| AEA | –6.09 ± 0.19 | 47.9 ± 3.6 | X | X | X | X | X | X |
| THC | NA∧ | 5.9 ± 3.1∧ | X | X | NA∧ | –3.8 ± 4.3∧ | X | X |
| BAY | NA∧ | 15.3 ± 4.6∧ | X | X | X | X | X | X |
| JWH-015 | X | X | X | X | –7.07 ± 0.21 | 34.0 ± 2.6 | X | X |
| JWH-133 | X | X | X | X | –6.55 ± 0.04§ | 37.8 ± 2.3 | X | X |
X, Not determined; NA, Not active. ∧A concentration–response curve could not be fitted; therefore, efficacy at 10 μM is noted instead of Emax. §Value is significantly different to bovine β-arrestin-2 for the same ligand. ΔValue is significantly different in the presence of GRK2 compared to the absence of GRK2 for the same ligand.