title: The relationship between protein synthesis and protein degradation in object recognition memory.
abstract: For decades there has been a consensus that de novo protein synthesis is necessary for long-term memory. A second round of protein synthesis has been described for both extinction and reconsolidation following an unreinforced test session. Recently, it was shown that consolidation and reconsolidation depend not only on protein synthesis but also on protein degradation by the ubiquitin-proteasome system (UPS), a major mechanism responsible for protein turnover. However, the involvement of UPS on consolidation and reconsolidation of object recognition memory remains unknown. Here we investigate in the CA1 region of the dorsal hippocampus the involvement of UPS-mediated protein degradation in consolidation and reconsolidation of object recognition memory. Animals with infusion cannulae stereotaxically implanted in the CA1 region of the dorsal hippocampus, were exposed to an object recognition task. The UPS inhibitor β-Lactacystin did not affect the consolidation and the reconsolidation of object recognition memory at doses known to affect other forms of memory (inhibitory avoidance, spatial learning in a water maze) while the protein synthesis inhibitor anisomycin impaired the consolidation and the reconsolidation of the object recognition memory. However, β-Lactacystin was able to reverse the impairment caused by anisomycin on the reconsolidation process in the CA1 region of the hippocampus. Therefore, it is possible to postulate a direct link between protein degradation and protein synthesis during the reconsolidation of the object recognition memory.
authors.affiliation: National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, and Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690 - 2nd Floor, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Cristiane R G
authors.initials: CR
authors.lastname: Furini
authors.affiliation: National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, and Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690 - 2nd Floor, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Jociane de C
authors.initials: Jde C
authors.lastname: Myskiw
authors.affiliation: National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, and Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690 - 2nd Floor, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Bianca E
authors.initials: BE
authors.lastname: Schmidt
authors.affiliation: National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, and Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690 - 2nd Floor, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Carolina G
authors.initials: CG
authors.lastname: Zinn
authors.affiliation: National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, and Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690 - 2nd Floor, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Patricia B
authors.initials: PB
authors.lastname: Peixoto
authors.affiliation: National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, and Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690 - 2nd Floor, 90610-000 Porto Alegre, RS, Brazil.
authors.forename: Luiza D
authors.initials: LD
authors.lastname: Pereira
authors.affiliation: National Institute of Translational Neuroscience (INNT), National Research Council of Brazil, and Memory Center, Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690 - 2nd Floor, 90610-000 Porto Alegre, RS, Brazil. Electronic address: izquier@terra.com.br.
authors.forename: Ivan
authors.initials: I
authors.lastname: Izquierdo
mesh_terms: D000111:Acetylcysteine / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D000841:Anisomycin / Q000494:pharmacology; D056547:CA1 Region, Hippocampal / Q000187:drug effects / Q000378:metabolism*; D002408:Catheters, Indwelling; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D008297:Male; D009483:Neuropsychological Tests; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D059748:Proteolysis / Q000187:drug effects; D017208:Rats, Wistar; D021641:Recognition, Psychology / Q000187:drug effects / Q000502:physiology*; D025801:Ubiquitin / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D015853:Cysteine Proteinase Inhibitors; D011500:Protein Synthesis Inhibitors; D025801:Ubiquitin; C067713:lactacystin; D000841:Anisomycin; D046988:Proteasome Endopeptidase Complex; D000111:Acetylcysteine
keywords: Consolidation; Hippocampus; Protein degradation; Protein synthesis; Recognition memory; Reconsolidation