Receptor and Site of Action | Effects | Agonist | Antagonist |
---|---|---|---|
μ | |||
Systemic | Analgesia | DAMGO | CTOP |
Euphoria | Morphine | Naloxone | |
Constipation | Fentanyl | ||
Respiratory depression | Endomorphins | ||
β-Endorphin | |||
Peripheral | Analgesia | DiPOA | Alvimopan |
Constipation | HS731/AS006 | Naloxone methiodide | |
Reduced inflammation | Loperamide | Methylnaltrexone | |
Frakefamide | |||
DALDA | |||
δ | |||
Systemic | Analgesia | DPDPE | Naltrindole |
Constipation | SNC 80 | ICI 174,864 | |
Respiratory depression | Enkephalins | Naloxone | |
Deltorphin | |||
β-Endorphin | |||
Peripheral | Analgesia | UK-321,130 | Naloxone methiodide |
Constipation | |||
κ | |||
Systemic | Analgesia | U-69593, U50,488 | Norbinaltorphimine |
Diuresis | Bremazocine | Naloxone | |
Dysphoria | Dynorphin A-B | ||
Peripheral | Analgesia | Asimadoline | Naloxone methiodide |
Reduced inflammation | FE200665/CR845 |
DAMGO, [d-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin; CTOP, d-Phe-Cys-Tyr-d-Trp-Orn-Thr-Pen-Thr-NH2; HS731, 14-O-methyloxymorphone; DALDA, Tyr-Arg-Phe-Lys-NH2; DPDPE, [d-Pen2,d-Pen5]-enkephalin; SNC 80, 4-(α-(4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide; ICI 174,864, N,N-diallyl-Tyr-Aib-Aib-Phe-Leu; U-69593, N-methyl-2-phenyl-N-[(5R,7S,8S)-7-(pyrrolidin-1-yl)-1-oxaspiro[4.5]dec-8-yl]acetamide; U50,488, trans-3,4-dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide.