Opioid Receptor Mu 1 Subunit

The mu (μ) opioid receptor, encoded by the OPRM1 gene, is a principal component of the endogenous opioid system. It regulates pain perception, reward mechanisms, and addictive behaviors. Upon activation by endogenous or exogenous opioids, it couples to inhibitory G-proteins, leading to analgesia, euphoria, and other effects. Variants in OPRM1 are associated with altered risk for substance dependence and pain sensitivity.

Other names

Mu-type opioid receptorMORMOPOP3

Agonist binding to the mu-opioid receptor leads to activation of inhibitory G-proteins, resulting in decreased adenylyl cyclase activity, reduced cAMP levels, opening of potassium channels, closing of voltage-gated calcium channels, decreased neuronal excitability, and neurotransmitter release.