Table 1

Affinity (log Ki values) of β-adrenoceptor ligands for the β1-WT and β2-WT obtained from 3H-CGP12177 whole cell binding in cells stably transfected with whole TM or EL changes The values are mean ± S.E. mean for n separate experiments. The β1 over β2-selectivity for the wild-type receptors is also given, thus xamoterol had 20-fold higher affinity for β1 than β2.

Log Ki xamoterolnLog Ki nebivololn
β1-WT−7.19 ± 0.0425−8.33 ± 0.0514
β1-N−7.10 ± 0.115−8.18 ± 0.1110
β1-EL1−7.38 ± 0.085−8.35 ± 0.0710
β1-EL2−7.01 ± 0.115−8.11 ± 0.0910
β1-EL3−7.41 ± 0.135−8.10 ± 0.0910
β1-TM1−7.31 ± 0.088−8.53 ± 0.046
β1-TM2−6.35 ± 0.05****8−7.32 ± 0.07****6
β1-TM3−7.17 ± 0.088−8.15 ± 0.096
β1-TM4−7.41 ± 0.088−7.91 ± 0.09*6
β1-TM5−7.24 ± 0.088−8.28 ± 0.056
β1-TM6−6.97 ± 0.097−7.93 ± 0.05*6
β1-TM7−6.89 ± 0.107−8.06 ± 0.066
β2-WT−5.89 ± 0.0330−6.93 ± 0.0612
β2-N−5.97 ± 0.118−6.89 ± 0.0810
β2-EL1−5.85 ± 0.048−7.05 ± 0.0410
β2-EL2−6.06 ± 0.058−6.82 ± 0.059
β2-EL3−5.91 ± 0.068−7.15 ± 0.0710
β2-TM1−5.85 ± 0.048−7.05 ± 0.066
β2-TM2−6.84 ± 0.07****7−7.74 ± 0.12****6
β2-TM3−6.01 ± 0.078−6.76 ± 0.036
β2-TM4−5.68 ± 0.047−6.90 ± 0.036
β2-TM5−5.89 ± 0.036−6.95 ± 0.026
β2-TM6−6.09 ± 0.057−6.91 ± 0.056
β2-TM7−6.23 ± 0.04***9−6.97 ± 0.086
β1-selectivity20.025.1

  • ****P < 0.000001 One-way ANOVA with post hoc Tukey comparing values from the mutant receptors with those obtained from the β1-WT or the β2-WT.

  • ***P < 0.00003 and *P < 0.05 compared with β1-WT or the β2-WT.