sstr-2 and sstr-4 Affinities for Various Agonist 19F-Fluoroethyltriazole-Tyr3-Octreotate Ligands Expressed as Concentration at Which Half-Maximal Receptor Activation Occurs (Half-Maximal Effective Concentration, EC50)
Predicted agonist EC50 potency value | ||
Compound identity | sstr-2 | sstr-4 |
Somatostatin | 5.6 nM | 3.8 nM |
19F-FET-G-PEG-TOCA | 19.0 nM | >10 mM |
19F-FETE-PEG-TOCA | 12.0 nM | >10 mM |
19F-FET-βAG-TOCA | 4.7 nM | 8.6 mM |
19F-FET-G-TOCA | 6.9 nM | 5.4 mM |
19F-FETE-TOCA | 4.1 nM | 6.5 mM |
19F-FET-βAG-[W-c-(CTFTYC)K] | 220 nM | ND |
ND = could not be determined because of lack of activity.