Binding Affinities of CCK Receptor Ligand–Targeted Radioimaging Agents in HEK 293 Cells
| Compound | Kd (nM) of HEK 293 CCK2R cells | Kd (nM) of HEK 293 CCK2i4svR cells* |
| CRL-1 | 16 | |
| CRL-2 | 46 | 31 |
| CRL-3 | 30 | 4 |
| CRL-4 | 270 |
↵* Kd could not be determined for compounds CRL-1 and CRL-4 in HEK 293 CCK2i4svR cells because of very high levels of nonspecific binding of these compounds and significantly smaller numbers of receptors on these cells.