TABLE 4 Comparison of BoPz ligand binding properties at the EGFP(Δ17)hM1 receptor and its four mutants as assessed from equilibrium [3H]NMS and FRET binding measurements
Affinity constants (mean ± S.E. values for 3–5 independent determinations) for the fluorescent ligands are from competition experiments (Ki values) performed in the presence of a fixed [3H]NMS concentration or from saturation experiments (Kd values) taking each BoPz ligand as a FRET tracer over a 1 nM to 10 µM concentration range (Materials and Methods).