Opioid Receptor Mu-Type (MOR)

The mu-type opioid receptor (MOR) is a G protein-coupled receptor (GPCR) that plays a central role in mediating the effects of both endogenous and exogenous opioids. It is primarily responsible for analgesia, euphoria, respiratory depression, sedation, and inhibition of gastrointestinal transit. Activation leads to inhibition of adenylyl cyclase and altered ion channel activity. Drugs targeting MOR are widely used for pain management but carry significant risks including addiction potential and respiratory depression.

Other names

MOPhMOPMOR1MOR-1Mu opiate receptor

Agonist binding leads to Gi/o-mediated inhibition of adenylyl cyclase/cAMP production, opening of potassium channels, and closing of calcium channels. Phosphorylation leads to β-arrestin recruitment and downstream signaling.