Table 3
Affinity of N273Y and the wt human A2B receptors for 2-substituted agonists and representative antagonists
 | ||||
|---|---|---|---|---|
| Ligand | R | KiN273Y | Ki wt | Fold |
| μM | ||||
| 1 | -C≡C-(CH2)3-CH3 | 0.18 ± 0.10 | 11 ± 4.3 | 613-150 |
| 2 | -CH=CH-(CH2)3-CH3(E) | 2.5 ± 1.0 | 53 ± 23 | 213-150 |
| 3 | -NH-N=CH-CH2-CH(CH3)2 | 7.4 ± 2.9 | 26 ± 3.2 | 3.53-150 |
| 4 | -O-(CH2)2-(C6H4)-p-CH3 | 7.7 ± 1.9 | 47 ± 26 | 6.13-150 |
| CGS216803-a | -NH-(CH2)2-(C6H4)-p-(CH2)2-COOH | 95 ± 32 | 300 ± 44 | 3.23-150 |
| 2Cl Ado | -Cl | 26 ± 2.6 | 8.9 ± 3.4 | 0.33-150 |
| 5(LUF5599) | (R) -C≡C-CHOH(C6H5) | 2.9 ± 1.1 | 10 ± 4.5 | 3.4 |
| 6 (LUF5600) | (S) -C≡C-CHOH(C6H5) | 0.19 ± 0.1 | 1.7 ± 0.5 | 8.93-150 |
| ZM241385 | 0.064 ± 0.030 | 0.026 ± 0.007 | 0.4 | |
| SCH58261 | 0.39 ± 0.3 | 0.34 ± 0.16 | 0.9 | |
| XAC | 0.003 ± 0.001 | 0.008 ± 0.004 | 2.7 | |
K i values were determined in [3H]DPCPX binding experiments to transiently transfected COS-7 cells as described under Experimental Procedures. The fold difference is defined as the affinity of the ligand for the wt receptor divided by the affinity of the ligand for the mutant receptor. Data are shown as means ± SD.