Lesion of dopamine mesolimbic neurons blocks behavioral effects induced by the endogenous enkephalins but not by a mu-opioid receptor agonist.
Lesioning of dopamine neurons by injection of 6-hydroxydopamine into the nucleus accumbens blocked the increased rearing activity measured in the open-field and induced by injection into the ventral tegmental area of: [R)-3-(N-hydroxylcarboxamido-2-benzyl-propanoyl)-L-alanine), kelatorphan (complete inhibitor of enkephalin catabolism) or by (Tyr-D-Ser(OtBu)-Gly-Phe-Leu-Thr(OtBu)): BUBU (selective delta agonist) but not the hypolocomotion evoked by the mu agonist (Tyr-D-Ala-Gly-N(Me)-Phe-Glyol): DAMGO. This suggests the involvement of different neuronal pathways in mu and delta effects.
Calenco-Choukroun
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G
Pharmacochimie Moléculaire, INSERM U266, CNRS UA498, UFR des Sciences Pharmaceutiques et Biologiques, Paris, France.
Daugé
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V
Gacel
G
G
Roques
B P
BP
D000595:Amino Acid Sequence; D000700:Analgesics / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004151:Dipeptides / Q000494:pharmacology; D004298:Dopamine / Q000502:physiology*; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004745:Enkephalins / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D008032:Limbic System / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008969:Molecular Sequence Data; D009043:Motor Activity / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology; D016627:Oxidopamine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects / Q000502:physiology*; D017465:Receptors, Opioid, delta; D017450:Receptors, Opioid, mu; D013681:Tegmentum Mesencephali / Q000187:drug effects / Q000378:metabolism
D000700:Analgesics; D004151:Dipeptides; D004745:Enkephalins; D009842:Oligopeptides; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D017450:Receptors, Opioid, mu; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; C062971:tyrosyl-seryl(O-t-butyl)-glycyl-phenylalanyl-leucyl-threonine(O-t-butyl); C042591:kelatorphan; D016627:Oxidopamine; D004298:Dopamine