Four isomers of the Somatostatin analogue H-D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 (CTAP) were made with β-MePhe in position 1 and assayed for opioid binding in rat brain, biological activity in MVD and GPI bioassays, and antinociception in mouse warm-water tail flick assays. These analogues displayed varying potencies and biological activities including: simultaneous δ receptor agonism/μ receptor antagonism, μ receptor antagonism, and δ receptor agonism. These analogues demonstrated that the N-terminal residue is important for receptor potency/selectivity and signal transduction. These analogues may represent leads to therapeutic agents that yield analgesia via δ agonist effects, yet lack side effects associated with μ activity.
- antinocic eption
ASJC Scopus subject areas
- Cellular and Molecular Neuroscience