TABLE 3.
The influence of temperature on the binding to the β2-AR of the antagonist propranolol and the agonists isoproterenol, (R,R′)-Fen, (R,S′)-Fen, (S,R′)-Fen, and (S,S′)-Fen using [3H](R,R′)-MFen as the maker ligand, where n = 3
All values are Ki except for (R,R′)-MFen, which are Kd values derived from saturation analysis. These Kd values were used to calculate Ki for the remaining compounds, as described under Materials and Methods. See Materials and Methods for experimental procedures.
| Compound |
Ki |
||
|---|---|---|---|
| 4°C | 25°C | 37°C | |
| nM | |||
| (R,R′)-MFen | 5.68 ± 1.35 | 4.88 ± 0.41 | 3.66 ± 0.82 |
| Propranolol | 4.74 ± 1.94 | 3.69 ± 1.36 | 3.66 ± 0.66 |
| Isoproterenol | 4.40 ± 0.59 | 2.44 ± 0.28 | 1.89 ± 0.53 |
| (R,R′)-Fen | 7.97 ± 3.79 | 4.00 ± 0.75 | 2.59 ± 0.20 |
| (R,S′)-Fen | 187.40 ± 35 | 183 ± 30 | 83.00 ± 3.22 |
| (S,R′)-Fen | 3338 ± 764 | 1827 ± 117 | 1798.50 ± 198 |
| (S,S′)-Fen | 3800 ± 482 | 3370 ± 210 | 1639 ± 340 |