PZM21 is a μ-opioid receptor agonist (Ki = 1.1 nM).1 It is selective for μ- over κ- and δ-opioid receptors (Kis = 18 and 506 nM, respectively). PZM21 induces Gi/o signaling (EC50 = 4.6 nM in HEK293T cells expressing human receptors) but has no detectable activity in a β-arrestin2 recruitment assay. In vivo, PZM21 (10, 20, and 40 mg/kg) induces analgesia in the hot plate test and reduces formalin-induced paw licking in mice when administered at a dose of 40 mg/kg.
1.Manglik, A., Lin, H., Aryal, D.K., et al.Structure-based discovery of opioid analgesics with reduced side effectsNature537(7619)185-190(2016)