Heroin-induced locomotion and mesolimbic dopamine release is unchanged in mice lacking the ORL.1 receptor gene.
We sought evidence for a role of endogenous nociceptin in modulating opiate effects on locomotion and mesolimbic dopamine release. Heroin administration (1, 3 and 10 mg/kg) induced dose-dependent increases in locomotion and mesolimbic dopamine release. However, no differences were identified between wild-type and nociceptin receptor-deficient mice, suggesting that either these systems are not influenced by an endogenous nociceptin tone, or that compensatory mechanisms activated during development normalize the response.
Murphy
Niall P
NP
Department of Psychiatry, UCLA Neuropsychiatric Institute, 760 Westwood Plaza, Los Angeles, CA 90024-1759, USA.
Lam
Hoa A
HA
Chen
Zhenping
Z
Pintar
John E
JE
Maidment
Nigel T
NT
D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D003932:Heroin / Q000494:pharmacology*; D008032:Limbic System / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D009043:Motor Activity / Q000187:drug effects; D018847:Opioid Peptides / Q000502:physiology; D011957:Receptors, Opioid / Q000235:genetics*; D000094942:Nociceptin Receptor; D000097629:Nociceptin
D000701:Analgesics, Opioid; D004298:Dopamine; D003932:Heroin; D018847:Opioid Peptides; D011957:Receptors, Opioid; D000094942:Nociceptin Receptor; D000097629:Nociceptin; C000722287:Oprl1 protein, mouse