title: Spermidine improves fear memory persistence.
abstract: Persistence is the most characteristic attribute of long-term memory (LTM). For memory persistence, a second late event of consolidation, that occurs around 12h after the acquisition, is necessary. Although the N-methyl-d-aspartate (NMDA) receptor has been involved in the persistence of memory, whether endogenous modulators of the NMDA receptor actually modulate memory persistence is unknown. In the current study we investigated whether spermidine and arcaine, respectively agonist and antagonist of polyamine binding site at NMDA receptor, alter the persistence of the memory of contextual fear conditioning task in rats. While 12h post-training administration of spermidine (10 and 30mg/kg, i.p.) facilitated, arcaine (10mg/kg, i.p.) impaired the memory of fear assessed 2 and 7 days after training. Arcaine (0.1mg/kg) prevented the facilitatory effect of spermidine (10mg/kg, i.p.), and spermidine (1mg/kg), prevented the memory impairment induced by arcaine (10mg/kg, i.p.) when tested 2 and 7 days after training. These results suggest that endogenous polyamines improve the persistence of fear memory.
authors.affiliation: Graduation Program in Biological Sciences: Toxicological Biochemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Cristiane
authors.initials: C
authors.lastname: Signor
authors.affiliation: Graduation Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Mello
authors.affiliation: Graduation Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Gerusa P
authors.initials: GP
authors.lastname: Porto
authors.affiliation: Graduation Program in Biological Sciences: Toxicological Biochemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Daniela A
authors.initials: DA
authors.lastname: Ribeiro
authors.affiliation: Graduation Program in Biological Sciences: Toxicological Biochemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil; Graduation Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil. Electronic address: maribel.rubin@gmail.com.
authors.forename: Maribel A
authors.initials: MA
authors.lastname: Rubin
mesh_terms: D000818:Animals; D001645:Biguanides / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005239:Fear / Q000187:drug effects* / Q000523:psychology*; D008297:Male; D008568:Memory / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D013095:Spermidine / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D001645:Biguanides; C006624:arcaine; D013095:Spermidine
keywords: Arcaine; Long-term memory; Memory persistence; NMDA receptor; Polyamines; Spermidine