Table 1.
Major types of opioid receptors.
| Receptor Nomenclature 1 |
Gene | Most Common Location in the CNS 2 |
Most Common Roles and Functions |
Selective Agonist 3 |
Selective Antagonist 4 |
|---|---|---|---|---|---|
| μ, mu, MOP | OPRM1 | Thalamus, amygdala, dorsal horn, cerebral cortex, striatum, hippocampus, locus coeruleus | Analgesia, intestinal transit, feeding, mood, hormone secretion, thermoregulation, cardiovascular function | DAMGO, sufentanil, PL017 |
CTAP, CTOP, β-FNA |
| δ, delta, DOP | OPRD1 | Olfactory bulb, thalamus, cortex, caudate putamen, nucleus accumbens (NAc), amygdala, dorsal horn | Analgesia, mood, gastrointestinal motility, behaviour, cardiovascular regulation |
DPDPE, [D-Ala2]deltorphin I, [D-Ala2]deltorphin II SNC80 |
Naltrindole, TIPPᴪ, Naltriben |
| κ, kappa, KOP | OPRK1 | Olfactory bulb, NAc, cerebral cortex, claustrum, amygdala, caudate nucleus, hypothalamus, subthalamic nucleus, thalamus, corpus callosum. | Analgesia in inflammation, diuresis, feeding, neuroprotection, neuroendocrine functions |
Enadoline, U50488, U69593, salvinorin A |
norBNI, GNTI |
| N/OFQ, NOP | OPRL1 | Hippocampus, hypothalamus, amygdala, substantia nigra, dorsal horn, lateral septum | Spinal analgesia, anxiety, mood, memory, feeding, locomotor activity | UFP-102, Ro64-6198, N/OFQ-(1-13)-NH2, UFP-112 |
UFP-101, SB 612111, J-113397, JTC-801 |
1,2,3,4 Further detailed information can be obtained from IUPHAR/BPS guide to pharmacology (http://www.guidetopharmacology.org; accessed on: 26 October 2021) and Alexander and colleagues [14]. Abbreviations: β-funaltrexamine (β-FNA), [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO), norbinaltorphimine (norBNI), [D-Pen2, D-Pen5] enkephalin (DPDPE), nociceptin/orphanin-FQ (N/OFQ), H-Tyr–Tic–Phe–Phe-OH (TIPP).