Table 1.
Behavioral effects of MOR, KOR, and DOR drugs in preclinical studies
| Receptor | Drug Type | Compound | Route of Administration | Subregion | Species | Sex | Pain Model | Behavioral Effect | Behavioral Test | References |
|---|---|---|---|---|---|---|---|---|---|---|
| Systemic | ||||||||||
| MOR | Agonist | Morphine | i.p. | - | Mouse | Male | Formalin | Antinociceptive | Licking and biting time | Zeng 2021 |
| i.p. | Mouse | Male | CCI | Increased preference behavior | CPP | Kai 2018 | ||||
| Oral | Rat | Both | Naïve | Antinociceptive (in male offspring) | Hot plate test, acetic acid writhing test | Ashabi 2018 | ||||
| Formalin | Licking time | |||||||||
| s.c. | Mouse | Male | Hindpaw incision | Increased preference behavior | CPP | Nwaneshiudu 2020 | ||||
| i.v. | Rat | Male | SNL | Antinociceptive | von Frey test | Navratilova 2015b | ||||
| Increased preference behavior | CPP | |||||||||
| i.p. | Rat | Male | SNL | Antinociceptive | von Frey test | LaGraize 2006 | ||||
| Decreased avoidance behavior | LDB | |||||||||
| i.p. | Rat | Male | NMDA-induced CeA lesion | No effect | Formalin test | Manning 1995a | ||||
| NMDA-induced BLA lesion | Antinociceptive | |||||||||
| i.p. | Rat | Male | NMDA-induced CeA lesion | No effect | Tail flick test | Manning 1995b | ||||
| Fentanyl (long-term) | s.c. | Rat | Male | Naïve | Pronociceptive | von Frey test, Hargreaves test | Wang 2022 | |||
| Remifentanil (long-term) | i.v. | Mouse | Female | Naïve | Increased cognitive deficits | ED shift task | Anderson 2021 | |||
| Male | No effect | |||||||||
| Female | Naïve | Increased depressive-like behavior | FST | |||||||
| Male | No effect | |||||||||
| Agonist + antagonist | Morphine + naloxone | s.c. + intra-NAc microinjection | Rat | Male | Naïve | Pronociceptive | Hot plate test | Dill 1977 | ||
| s.c. + intra-CN microinjection | No effect | |||||||||
| s.c. + intra-GP microinjection | No effect | |||||||||
| Agonist + acetaldehyde dehydrogenase inhibitor | Morphine + disulfram | Oral | Rat | Male | Naïve | Antinociceptive | Randall-Selitto test, tail flick test | de Corde-Skurska 2021 | ||
| Antagonist + agonist | Naloxone + morphine | i.p. + intra-ACC microinjection | Rat | Male | SNL | No effect | von Frey test | LaGraize 2006 | ||
| No effect | LDB | |||||||||
| KOR | Agonist | U69,593 (long-term) | s.c. | Rat | Male | Naïve | Increased aversion behavior | CPA | Tejeda 2013 | |
| U69,593 | s.c. | Mouse | Male | KOR KO on dopaminergic neurons | Decreased aversive behavior | CPA | Chefer 2013 | |||
| Antagonist | nor-BNI | s.c. | Rat | Male | Naïve | No effect | OFT | Tejeda 2015 | ||
| DOR | Antagonist | NTI | s.c. | Mouse | Male | Naïve | Increased anxiety-like behavior | LDB, EPM | Narita 2006b | |
| mPFC | ||||||||||
| MOR | Agonist | Morphine | Microinjection | ACC | Rat | Male | Incision model | Increased preference behavior | CPP | Navratilova 2015b |
| No effect | von Frey test | |||||||||
| SNL | Increased preference behavior | CPP | ||||||||
| No effect | von Frey test | |||||||||
| Microinjection | ACC | Rat | Male | SNL | No effect | von Frey test | LaGraize 2006 | |||
| Decreased avoidance behavior | LDB | |||||||||
| Microinjection | rostral ACC, caudal ACC | Rat | Male | SNL | No effect | Tail flick assay, von Frey test, Randall-Selitto test, Hargreaves test | Gomtsian 2018 | |||
| rostral ACC | Increased preference behavior | CPP | ||||||||
| caudal ACC | No effect | |||||||||
| Microinjection | ACC | Rat | Male | CCI | Antinociceptive | Randall-Selitto test, hot plate test | Wang 2020 | |||
| Agonist + antagonist | Morphine + naloxone | No effect | ||||||||
| Morphine + β-FNA | No effect | |||||||||
| Antagonist | Naloxonazine | Microinjection | PL | Rat | Male | Orofacial formalin | Pronociceptive | Face rubbing | Tamaddonfard 2020 | |
| Naloxone | Microinfusion | PL | Rat | Male | SNL | Pronociceptive | von Frey test | Zeng 2018 | ||
| Microinjection | ACC | Rat | Male | Incision model | Decreased preference behavior | CPP | Navratilova 2015b | |||
| No effect | von Frey test | |||||||||
| SNL | Decreased preference behavior | CPP | ||||||||
| No effect | von Frey test | |||||||||
| Antagonist + agonist | β-FNA + morphine | Microinjection + i.v. | Antinociceptive | von Frey test | ||||||
| Decreased preference behavior | CPP | |||||||||
| Selective ablation of MOR-expressing neurons | Derm-SAP | Microinjection | Decreased preference behavior | CPP | ||||||
| No effect | Hargreaves test | |||||||||
| Antagonist + agonist | β-FNA + morphine | Microinjection | right ACC + right CeA | Rat | Male | SNL | Decreased preference behavior | CPP | Navratilova 2020 | |
| KOR | Antagonist | nor-BNI | Microinfusion | PL | Rat | Male | U69,593-conditioned | Decreased aversion behavior | CPA | Tejeda 2013 |
| Microinfusion | PL | Rat | Male | Naïve | Decreased anxiety-like behavior | OFT | Tejeda 2015 | |||
| DOR | Agonist | DADLE | Microinjection | rostral ACC | Rat | Male | CFA | Decreased aversion behavior | CPA | Ma 2022 |
| No effect | Hot plate test | |||||||||
| KNT-127 | Microinfusion | PL | Mouse | Male | Naïve | No effect | OFT | Saitoh 2018 | ||
| Agonist + sodium channel activator | KNT-127 + veratrine | Decreased anxiety-like behavior | ||||||||
| Antagonist | Naltrindole | Microinjection | ACC | Mouse | Male | Naïve | Increased anxiety-like behavior | LDB, EPM | Narita 2006b | |
| Amygdala | ||||||||||
| MOR | Agonist | Morphine | Microinjection | right CeA | Rat | Male | SNL | No effect | von Frey test, Randall-Selitto test | Navratilova 2020 |
| Increased preference behavior | CPP | |||||||||
| left CeA | No effect | von Frey test, Randall-Selitto test, CPP | ||||||||
| Microinjection | BLA | Rat | Male | Naïve | Antinociceptive | Tail flick test | Helmstetter 1995 | |||
| Microinjection | BLA | Rat | Male | Naïve | Antinociceptive | Tail flick test, jump test | Pavlovic 1996 | |||
| CeA | ||||||||||
| Microinfusion | BLA | Rat | Male | Naïve | Antinociceptive | Tail flick test | McGaraughty 2002 | |||
| DAMGO | Microinjection | BLA | Rat | Male | Naïve | Antinociceptive | Tail flick test | Helmstetter 1998 | ||
| Microinjection | CeA | Rat | Male | CFA | Decreased aversion behavior | CPA | Zhang 2013 | |||
| No effect | Hargreaves test | |||||||||
| β-endorphin | Microinjection | BLA | Rat | Male | Naïve | Antinociceptive | Tail flick test, jump test | Pavlovic 1996 | ||
| CeA | ||||||||||
| Agonist + antagonist | Morphine + naltrexone | Microinjection | BLA + PAG | No effect | ||||||
| β-endorphin + naltrexone | ||||||||||
| Antagonist | CTAP | Microinjection | CeA | Mouse | Both | Plantar incision model | Pronociceptive | von Frey test | Cooper 2022 | |
| Chemogenetic inhibition of MOR-expressing PB input neurons | AAVDJ-EF1a-DIO-hM4D(Gi)-mCherry | Microinjection | CeA | Mouse | Both | Formalin | Antinociceptive | Hot plate test | Liu 2022 | |
| Decreased anxiety-like behavior | EPM | |||||||||
| KOR | Agonist | U69,593 | Microinfusion | right CeA | Rat | Male | Naïve | Increased emotional-affective responses | Vocalizations to noxious stimulus | Hein 2021 |
| Increased anxiety-like behavior | OFT | |||||||||
| Decreased preference behavior | CPP | |||||||||
| No effect | Paw pressure test | |||||||||
| Antagonist | nor-BNI | Microinfusion | right CeA | Rat | Male | SNL | Decreased gabapentin-induced preference behavior | CPP | Navratilova 2019 | |
| No effect | von Frey test | |||||||||
| Microinfusion | right CeA | Rat | Male | Functional pain model | Decreased emotional-affective responses | Vocalizations to noxious stimulus | Yakhnitsa 2022 | |||
| Decreased anxiety-like behavior | EPM | |||||||||
| Antinociceptive | von Frey test | |||||||||
| No effects | Paw pressure test | |||||||||
| Microinfusion | right CeA | Rat | Male | Medication overuse model | Antinociceptive | von Frey test | Xie 2017 | |||
| left CeA | No effect | |||||||||
| Microinfusion | right CeA | Rat | Male | Infraorbital CCI | Antinociceptive | von Frey test | Turnes 2022 | |||
| No effect | EPM | |||||||||
| left CeA | No effect | von Frey test, EPM | ||||||||
| Microinjection | right CeA | Rat | Male | SNL + capsaicin | Antinociceptive | Randall-Selitto test | Phelps 2019 | |||
| left CeA | No effect | |||||||||
| Microinjection | right CeA | Rat | Male | Functional pain model | Antinociceptive | Randall-Selitto test | Nation 2018 | |||
| left CeA | No effect | |||||||||
| DOR | Agonist | DPDPE | Microinfusion | CeA | Mouse | Male | Naïve | Pronociceptive | von Frey test | Zhou 2021 |
| No effect | OFT, EPM | |||||||||
| CFA | No effect | von Frey test, OFT, EPM | ||||||||
| Deltorphin II | Naïve | No effect | von Frey test, OFT, EPM | |||||||
| CFA | No effect | Von Frey test | ||||||||
| Decreased anxiety-like behavior | OFT, EPM | |||||||||
| DOR1 antagonist | BNTX | No effect | ||||||||
| DOR2 antagonist | Naltriben | Increased anxiety-like behavior | ||||||||
| Antagonist | Naltrindole | Microinjection | BLA | Mouse | Male | CFA | Increased anxiety-like behavior | LDB, EPM | Narita 2006a | |
| CCI | ||||||||||
| NAc | ||||||||||
| MOR | Agonist | Morphine | Microinjection | n.s. | Rat | Male | Naïve | Antinociceptive | Hot plate test | Dill 1977 |
| Microinfusion | n.s. | Rat | Male | SNL | Antinociceptive | Hot plate test, Randall-Selitto test | Bian 2015 | |||
| DAMGO | Microinjection | n.s. | Rat | Male | Naïve | No effect | Jaw-opening reflex | Schmidt 2002 | ||
| Antagonist | CTOP | Microinjection | n.s. | Rat | Male | DAMGO-induced antinociception | Pronociceptive | Jaw-opening reflex | Gear 2011 | |
| Microinjection | n.s. | Rat | Male | Capsaicin-induced antinociception | Pronociceptive | Jaw-opening reflex | Schmidt 2022 | |||
| Microinjection | n.s. | Rat | Male | UFP-512-induced anxiolytic and antidepressant effects | Increased anxiety- and depressive-like behavior | EPM, novelty-induced hypophagia test | Kabli 2014 | |||
| Naloxone | Microinjection | n.s. | Rat | Male | Capsaicin-induced antinociception | Pronociceptive | Jaw-opening reflex | Gear 1999 | ||
| Dopamine receptor antagonist + agonist | α-flupenthixol + morphine | Microinjection | NAc + rostral ACC | Rat | Male | SNL | Decreased preference behavior | CPP | Navratilova 2015b | |
| MOR + DOR | Agonist + agonist | DAMGO + DPDPE | Microinjection | n.s. | Rat | Male | Naïve | Antinociceptive | Jaw-opening reflex | Schmidt 2002 |
| UFP-512 | Microinjection | n.s. | Rat | Male | Naïve | Decreased anxiety- and depressive-like behavior | EPM, novelty-induced hypophagia test | Kabli 2014 | ||
| KOR | Photoactivation of dynorphin neurons | - | Optical activation | ventral NAc shell | Mouse | Both | Naïve | Decreased motivation | Sucrose self-administration | Massaly 2019 |
| Increased aversion behavior | Real-time place aversion | |||||||||
| NAc shell cold spot | Rat | Male | CFA | Increased aversion behavior | ||||||
| Photostimulation | ventral NAc shell | Mouse | Male | Naïve | Increased aversion behavior | Real-time place aversion | Al-Hasani 2015 | |||
| No effect | OFT | |||||||||
| dorsal NAc shell | Increased preference behavior | Real-time place preference | ||||||||
| No effect | OFT | |||||||||
| Photoactivation of dynorphin neurons + antagonist | nor-BNI | Microinjection | NAc shell cold spot | Rat | Male | CFA | Decreased aversion behavior | Real-time place aversion | Massaly 2019 | |
| Agonist | U69,593 | Microinjection | n.s. | Rat | Male | Capsaicin-induced antinociception | Pronociceptive | Jaw-opening reflex | Schmidt 2022 | |
| DAMGO-induced antinociception | ||||||||||
| DPDPE-induced antinociception | ||||||||||
| E-2078 | Microinjection | n.s. | Rat | Male | Naïve | Increased aversion behavior | CPA | Bals-Kubik 1993 | ||
| U50,488 | ||||||||||
| Microinjection | n.s. | Mouse | Male | Naïve | Increased anxiety-like behavior | EPM, LDB | Wang 2016 | |||
| Antagonist | nor-BNI | U50,488-induced anxiety-like behavior | Decreased anxiety-like behavior | EPM | ||||||
| Microinfusion | NAc shell | Rat | Male | Learned helplessness model | Decreased depressive-like behavior | Conditioned avoidance test | Shirayama 2004 | |||
| Microinjection | ventral NAc shell | Mouse | Both | Dynorphin neuron stimulation | Decreased aversive behavior | Real-time place aversion | Massaly 2019 | |||
| Chemogenetic silencing of dynorphin neurons | Dyn2.0-hM4Di-IRES-mCherry | Microinjection | NAc shell cold spot | Rat | Male | Naïve | Increased motivation | Sucrose self-administration | ||
| DOR | Agonist | DPDPE | Microinjection | n.s. | Rat | Male | Naïve | No effect | Jaw-opening reflex | Schmidt 2002 |
| Antagonist | Naltrindole | Microinjection | n.s. | Rat | Male | DAMGO-induced antinociception | Pronociceptive | Jaw-opening reflex | Gear 2011 | |
| Microinjection | n.s. | Rat | Male | Capsaicin-induced antinociception | Pronociceptive | Jaw-opening reflex | Schmidt 2002 | |||
| Microinjection | n.s. | Rat | Male | UFP-512-induced anxiolytic and antidepressant effects | Increased anxiety- and depressive-like behavior | EPM, novelty-induced hypophagia test | Kabli 2014 | |||
β-FNA, β-funaltrexamine; BNTX, 7-benzylidenenaltrexone; CCI, chronic constriction injury; CeA, central nucleus of the amygdala; CFA, complete Freund’s adjuvant; CMS, chronic mild stress; CN, caudate nucleus; CPA, conditioned place aversion; CPP, conditioned place preference; CTOP, [Cys2-Tyr3-Orn5-Pen7]-amide; DADLE, [D-Ala2, D-Leu5]-enkephalin; DAMGO, D-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin; Derm-SAP, dermorphin-saporin; DPDPE, D-Pen2,5 enkephalin D-Pen2,5-enkephalin; ED, extradimensional shift task; EPM, elevated plus maze; FST, forced swim test; GP, globus pallidus; i.p., intraperitoneal; i.v., intravenous; KO, knock out; LDB, light/dark box; mPFC, medial prefrontal cortex; NMDA, N-methyl-D-aspartate; nor-BNI, nor-binaltorphimine; n.s., not specified; NTI, naltrindole; OFT, open field test; PB, parabrachial nucleus; PL, prelimbic; RVM, rostral ventromedial medulla; s.c., subcutaneous; SNL, spinal nerve ligation; TST, tail suspension test; UFP-512, (H-Dmt-Tic-NH-CH(CH2-COOH)-Bid); vlPAG, ventrolateral periaqueductal gray