Table 2. Summary of Antagonist Potency at κ- and μ-Receptors in the Isolated Guinea Pig Ileum Preparationa.
| antagonist potency (pA2) |
||
|---|---|---|
| ligand | κ | μ |
| BU09057 | 6.87 (7.13–6.35) (134.9 nM) | 7.01 (7.89–6.79) (97.7 nM) |
| BU09058 | 6.76 (7.45–6.05) (173.8 nM) | 7.03 (7.32–6.90) (93 nM) |
| BU09059 | 8.62 (9.12–8.03) (2.39 nM) | |
| NorBNI | 8.30 (10.3–7.72) (5.0 nM) | |
a
pA2 values were determined by Schild plot analysis. Values are the mean and 95% confidence interval for n = 4 tissues. Values for the prototypic κ-antagonist norBNI were obtained from our previously published data.25 Mean values are also shown as nM.