Opioid Receptor (OR)

Opioid receptors are a group of inhibitory G protein-coupled receptors (GPCRs) that mediate the effects of endogenous and exogenous opioids. These receptors play a central role in pain modulation, reward, addiction, and various physiological processes. There are three main classical opioid receptor subtypes: Mu (μ), Delta (δ), and Kappa (κ), as well as the Nociceptin/orphanin FQ peptide (NOP) receptor. Activation results in decreased neuronal excitability and reduced neurotransmitter release.

Other names

Opioid receptorsOpioid receptor family

Agonist binding induces conformational change, activating G proteins. Gαi/o subunit inhibits adenylyl cyclase, reducing cAMP levels, and modulates ion channels, leading to decreased neuronal excitability and reduced neurotransmitter release.