CTOP is an opioid antagonist cyclic peptide related to somatostatin.[1] It has been used in research about other opioid ligands.[2][3]
Pharmacology
CTOP is described as a highly potent mu-opioid receptor antagonist. In mice, its analgesic effects are qualified as being more potent than naloxone’s, a well-known opioid antagonist typically used as an antidote in humans.[4] Additionally, CTOP appears to lack significant affinity at the delta and kappa opioid receptors, suggesting that this peptide is selective for the μ receptor.[5]
References
- ^ PubChem. “Phenylalanyl-cyclo(cysteinyltyrosyl-tryptophyl-ornithyl-threonyl-penicillamine)threoninamide”. pubchem.ncbi.nlm.nih.gov. Retrieved 2026-01-01.
- ^ Soini, S. L.; Ovaska, T.; Honkanen, A.; Hyytiä, P.; Korpi, E. R. (April 1998). “Brain opioid receptor binding of [3H]CTOP and [3H]naltrindole in alcohol-preferring AA and alcohol-avoiding ANA rats”. Alcohol (Fayetteville, N.Y.). 15 (3): 227–232. doi:10.1016/s0741-8329(97)00125-0. ISSN 0741-8329. PMID 9539380.
- ^ Leite dos Santos, Gisele Graça; Casais e Silva, Luciana Lyra; Pereira Soares, Milena Botelho; Villarreal, Cristiane Flora (November 2012). “Antinociceptive properties of Micrurus lemniscatus venom”. Toxicon. 60 (6): 1005–1012. Bibcode:2012Txcn…60.1005L. doi:10.1016/j.toxicon.2012.07.003. ISSN 1879-3150. PMID 22841808.
- ^ Gulya, K.; Kriván, M.; Nyolczas, N.; Sarnyai, Z.; Kovács, G. L. (1988-06-10). “Central effects of the potent and highly selective mu opioid antagonist D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP) in mice”. European Journal of Pharmacology. 150 (3): 355–360. doi:10.1016/0014-2999(88)90018-0. ISSN 0014-2999. PMID 2901358.
- ^ Hawkins, K. N.; Knapp, R. J.; Gehlert, D. R.; Lui, G. K.; Yamamura, M. S.; Roeske, L. C.; Hruby, V. J.; Yamamura, H. I. (1988). “Quantitative autoradiography of [3H]CTOP binding to mu opioid receptors in rat brain”. Life Sciences. 42 (25): 2541–2551. doi:10.1016/0024-3205(88)90322-0. ISSN 0024-3205. PMID 2898716.