Group of biological receptors
An animated view of the human κ-opioid receptor in complex with the antagonist JDTic .
Opioid receptors are a group of inhibitory G protein-coupled receptors with opioids as ligands .[ 1] [ 2] [ 3] The endogenous opioids are dynorphins , enkephalins , endorphins , endomorphins and nociceptin . The opioid receptors are ~40% identical to somatostatin receptors (SSTRs). Opioid receptors are distributed widely in the brain , in the spinal cord , on peripheral neurons, and digestive tract .
^ Dhawan BN, Cesselin F, Raghubir R, Reisine T, Bradley PB, Portoghese PS, Hamon M (December 1996). "International Union of Pharmacology. XII. Classification of opioid receptors" . Pharmacological Reviews . 48 (4): 567–92. PMID 8981566 .
^ Janecka A, Fichna J, Janecki T (2004). "Opioid receptors and their ligands". Current Topics in Medicinal Chemistry . 4 (1): 1–17. doi :10.2174/1568026043451618 . PMID 14754373 .
^ Waldhoer M, Bartlett SE, Whistler JL (2004). "Opioid receptors". Annual Review of Biochemistry . 73 : 953–90. doi :10.1146/annurev.biochem.73.011303.073940 . PMID 15189164 .