Beta-endorphin-(1-27) is a Naturally Occurring Antagonist to Etorphine-induced Analgesia
Overview
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The potent opioid peptide beta-endorphin is found in the brain and pituitary with two related fragments, beta-endorphin-(1-27) and beta-endorphin-(1-26). The fragments retain substantial opioid-receptor binding activity but are virtually inactive analgesically. beta-Endorphin-(1-27) inhibits beta-endorphin-induced and etorphine-induced analgesia when coinjected intracerebroventricularly into mice. Antagonism by competition at the same site(s) is suggested from parallel shifts of the dose-response curves of etorphine or beta-endorphin in the presence of beta-endorphin-(1-27). Its potency is 4-5 times greater than that of the opiate antagonist naloxone. beta-Endorphin-(1-26) does not antagonize the antinociceptive action of etorphine or beta-endorphin in doses up to 500 pmol per animal.
Garzon-Nino J, Cortes-Montero E, Rodriguez-Munoz M, Sanchez-Blazquez P Int J Mol Sci. 2023; 24(1).
PMID: 36614024 PMC: 9820303. DOI: 10.3390/ijms24010582.
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Lindberg I, Fricker L Endocrinology. 2021; 162(12).
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Roles of β-Endorphin in Stress, Behavior, Neuroinflammation, and Brain Energy Metabolism.
Pilozzi A, Carro C, Huang X Int J Mol Sci. 2021; 22(1).
PMID: 33396962 PMC: 7796446. DOI: 10.3390/ijms22010338.
Five Decades of Research on Opioid Peptides: Current Knowledge and Unanswered Questions.
Fricker L, Margolis E, Gomes I, Devi L Mol Pharmacol. 2020; 98(2):96-108.
PMID: 32487735 PMC: 7330675. DOI: 10.1124/mol.120.119388.
Biased signaling by endogenous opioid peptides.
Gomes I, Sierra S, Lueptow L, Gupta A, Gouty S, Margolis E Proc Natl Acad Sci U S A. 2020; 117(21):11820-11828.
PMID: 32393639 PMC: 7261131. DOI: 10.1073/pnas.2000712117.