TABLE 1.

Chemical Structures, Binding Affinity, and Agonistic Potency of Bicyclic Somatostatin-Based Analogs

Binding affinity
CodeChemical structuresst1sst2sst3sst4sst5Functional test
SRIF-282.5 ± 0.32.6 ± 0.23.0 ± 0.52.6 ± 0.52.4 ± 0.2
HR3005cyclo(Arg-cyclo(Cys-Phe-D-Trp-Lys-Thr-Cys)-GABA)34 ± 102.4 ± 0.63.4 ± 0.868 ± 2214.5 ± 4.5sst2: agonist; sst3: agonist
AM8cyclo(Arg-cyclo(Cys-Phe-D-Trp-Lys-Thr-Cys)-DAB)52 ± 132.7 ± 0.13.4 ± 1.175 ± 2111.7 ± 1.7sst2: agonist; sst3: agonist
AM1DOTA-cyclo(DAB-Arg-cyclo(Cys-Phe-D-Trp-Lys-Thr-Cys))124 ± 711.0 ± 1.018.0 ± 2.0141 ± 2535 ± 12sst2: agonist; sst3: agonist
AM2DOTA-cyclo(DAB-Arg-cyclo(Cys-Tyr-D-Trp-Lys-Thr-Cys))866 ± 12021 ± 5169 ± 29154 ± 3559 ± 8sst2: agonist; sst3: agonist
AM3DOTA-Tyr-cyclo(DAB-Arg-cyclo(Cys-Phe-D-Trp-Lys-Thr-Cys))119 ± 62.3 ± 0.24.0 ± 0.0397 ± 2127 ± 1sst2: agonist; sst3: agonist

  • Values are mean inhibitory concentration of 50% (IC50) ± SEM (nM; n ≥ 3).