title: Spermidine-induced improvement of reconsolidation of memory involves calcium-dependent protein kinase in rats.
abstract: In this study, we determined whether the calcium-dependent protein kinase (PKC) signaling pathway is involved in the improvement of fear memory reconsolidation induced by the intrahippocampal administration of spermidine in rats. Male Wistar rats were trained in a fear conditioning apparatus using a 0.4-mA footshock as an unconditioned stimulus. Twenty-four hours after training, animals were re-exposed to the apparatus in the absence of shock (reactivation session). Immediately after the reactivation session, spermidine (2-200 pmol/site), the PKC inhibitor 3-[1-(dimethylaminopropyl)indol-3-yl]-4-(indol-3-yl) maleimide hydrochloride (GF 109203X, 0.3-30 pg/site), the antagonist of the polyamine-binding site at the NMDA receptor, arcaine (0.2-200 pmol/site), or the PKC activator phorbol 12-myristate 13-acetate (PMA, 0.02-2 nmol/site) was injected. While the post-reactivation administration of spermidine (20 and 200 pmol/site) and PMA (2 nmol/site) improved memory reconsolidation, GF 109203X (1, 10, and 30 pg/site) and arcaine (200 pmol/site) impaired it. GF 109203X (0.3 pg/site) impaired memory reconsolidation in the presence of spermidine (200 pmol/site). PMA (0.2 nmol/site) prevented the arcaine (200 pmol/site)-induced impairment of memory reconsolidation. Anisomycin (2 µg/site) also impaired memory reconsolidation in the presence of spermidine (200 pmol/site). Drugs had no effect when they were administered in the absence of reactivation. These results suggest that the spermidine-induced enhancement of memory reconsolidation involves PKC activation.
authors.affiliation: Graduate Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Bruna Amanda
authors.initials: BA
authors.lastname: Girardi
authors.affiliation: Graduate Program in Biological Sciences: Toxicological Biochemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Daniela Aymone
authors.initials: DA
authors.lastname: Ribeiro
authors.affiliation: Graduate Program in Biological Sciences: Toxicological Biochemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Cristiane
authors.initials: C
authors.lastname: Signor
authors.affiliation: Undergraduate in Pharmacy, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Michele
authors.initials: M
authors.lastname: Muller
authors.affiliation: Undergraduate in Pharmacy, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Mayara Ana
authors.initials: MA
authors.lastname: Gais
authors.affiliation: Graduate Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Carlos Fernando
authors.initials: CF
authors.lastname: Mello
authors.affiliation: Graduate Program in Pharmacology, Center of Health Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil Graduate Program in Biological Sciences: Toxicological Biochemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria, Santa Maria, RS 97105-900, Brazil maribel.rubin@gmail.com.
authors.forename: Maribel Antonello
authors.initials: MA
authors.lastname: Rubin
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000841:Anisomycin / Q000494:pharmacology; D001645:Biguanides / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005239:Fear / Q000187:drug effects / Q000502:physiology; D006624:Hippocampus / Q000187:drug effects; D007211:Indoles / Q000494:pharmacology; D008297:Male; D008301:Maleimides / Q000494:pharmacology; D008568:Memory / Q000187:drug effects*; D011494:Protein Kinases / Q000378:metabolism*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013095:Spermidine / Q000494:pharmacology*; D017871:Calcium-Calmodulin-Dependent Protein Kinases
chemical_list: D000841:Anisomycin; D001645:Biguanides; D004791:Enzyme Inhibitors; D007211:Indoles; D008301:Maleimides; D011494:Protein Kinases; D011500:Protein Synthesis Inhibitors; D013095:Spermidine; D017871:Calcium-Calmodulin-Dependent Protein Kinases; C006624:arcaine; C070515:bisindolylmaleimide I