β-Endorphin (1-27) (human)

β-Endorphin (1-27) (human) is an opioid antagonist that selectively binds to μ-, δ-, and κ-opioid receptors, with dissociation constants (Kis) of 5.31, 6.17, and 39.82 nM, respectively. It inhibits analgesia induced by both β-Endorphin and etorphine [1][2].

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