TABLE 1.
Binding affinity, potency and relative efficacy (Emax) of AngII to promote Ca2+ mobilization and β-arrestin 2 recruitment.
| Receptor | Binding | Ca2+ Mobilization | β-arrestin 2 recruitment | ||||||
|---|---|---|---|---|---|---|---|---|---|
| pIC50 | n | Kd (nM) | pEC50 | n | Emax (% WT) | pEC50 | n | Emax (% WT) | |
| WT | 9.00 ± 0.17 | 3 | 0.63 ± 0.51 | 8.89 ± 0.08 | 5 | 100 | 8.49 ± 0.05 | 3 | 100 |
| I103T | 8.63 ± 0.19 | 3 | 1.18 ± 0.94 | 9.57 ± 0.13* | 3 | 65 ± 4 | 8.54 ± 0.08 | 3 | 97 ± 2 |
| A244S | 8.19 ± 0.12* | 3 | 6.33 ± 2.0 | 9.07 ± 0.17 | 5 | 85 ± 15 | 8.68 ± 0.10 | 3 | 106 ± 2 |
| I103T-A244S | 8.61 ± 0.10 | 3 | 2.15 ± 0.67 | 9.17 ± 0.09 | 3 | 81 ± 5 | 8.50 ± 0.10 | 3 | 50 ± 4 |
HEK293T expressing AT1R/mutant receptors were stimulated with various concentrations of AngII. Ang II binding affinities were obtained from [3H]-AngII competition binding assay. Ca2+ mobilization and BRET were normalized to the maximal response of WT (% Emax of WT) and then averaged. pEC50 and Emax were obtained from the nonlinear regression curve of the averaged data. Data represents the means ± SEM of three or more independent experiments. *p < 0.05 compared to the WT receptor.