title: State-dependent effect of dopamine D₁/D₅ receptors inactivation on memory destabilization and reconsolidation.
abstract: Object recognition memories (ORM) can incorporate new information upon reactivation. This update initially involves destabilization of the original memory, which is followed by restabilization of the upgraded engram through a reconsolidation process that requires gene expression and protein synthesis in the hippocampus. We found that when given in dorsal CA1 either immediately after training or 15 min before ORM reactivation in the presence of a novel object, the dopamine D1/D5 receptor antagonist SCH23390 did not affect ORM consolidation, expression or retention but impeded the amnesia caused by the post-retrieval administration of the mRNA synthesis inhibitor α-amanitin or the protein synthesis blocker anisomycin. This anti-amnesic effect was not observed when SCH23390 was given immediately after training and again 15 min before memory reactivation. Our results demonstrate that hippocampal D1/D5 receptors are not needed for formation, retrieval or post-retrieval restabilization of the ORM trace but are essential for its destabilization when reactivation occurs together with the incorporation of new information into the original memory. Importantly, they also suggest that reenactment of the animal's post-learning neurochemical milieu at the moment of memory reactivation can be a boundary condition for reconsolidation.
authors.affiliation: Memory Research Laboratory, Brain Institute, Federal University of Rio Grande do Norte (UFRN), Natal, Brazil.
authors.forename: Janine I
authors.initials: JI
authors.lastname: Rossato
authors.affiliation: Memory Research Laboratory, Brain Institute, Federal University of Rio Grande do Norte (UFRN), Natal, Brazil.
authors.forename: Cristiano A
authors.initials: CA
authors.lastname: Köhler
authors.affiliation: Memory Research Laboratory, Brain Institute, Federal University of Rio Grande do Norte (UFRN), Natal, Brazil.
authors.forename: Andressa
authors.initials: A
authors.lastname: Radiske
authors.affiliation: Center for Biosciences - Federal University of Rio Grande do Norte (UFRN), Natal, Brazil.
authors.forename: Ramón H
authors.initials: RH
authors.lastname: Lima
authors.affiliation: Memory Research Laboratory, Brain Institute, Federal University of Rio Grande do Norte (UFRN), Natal, Brazil.
authors.forename: Lia R M
authors.initials: LR
authors.lastname: Bevilaqua
authors.affiliation: Memory Research Laboratory, Brain Institute, Federal University of Rio Grande do Norte (UFRN), Natal, Brazil. Electronic address: martin.cammarota@neuro.ufrn.br.
authors.forename: Martín
authors.initials: M
authors.lastname: Cammarota
mesh_terms: D053959:Alpha-Amanitin / Q000494:pharmacology; D000818:Animals; D000841:Anisomycin / Q000494:pharmacology; D001552:Benzazepines / Q000494:pharmacology*; D018492:Dopamine Antagonists / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D000069077:Memory Consolidation / Q000187:drug effects* / Q000502:physiology; D009483:Neuropsychological Tests; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D017208:Rats, Wistar; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D050641:Receptors, Dopamine D5 / Q000037:antagonists & inhibitors / Q000378:metabolism; D021641:Recognition, Psychology / Q000187:drug effects* / Q000502:physiology
chemical_list: D053959:Alpha-Amanitin; D001552:Benzazepines; D018492:Dopamine Antagonists; D019384:Nucleic Acid Synthesis Inhibitors; D011500:Protein Synthesis Inhibitors; D017447:Receptors, Dopamine D1; C534628:SCH 23390; D050641:Receptors, Dopamine D5; D000841:Anisomycin
keywords: Gene expression; Hippocampus; Object recognition memory; Protein synthesis; Retrieval