title: Intrahippocampal spermidine administration improves inhibitory avoidance performance in rats.
abstract: Polyamines are polycations present at high concentrations in the mammalian brain. We investigated the effect of an intrahippocampal infusion of spermidine, a polyamine agonist, immediately post-training on the inhibitory avoidance learning paradigm in rats. Bilateral intrahippocampal microinjection of spermidine (0.02-20 nmol) caused an increase in test step-down latencies at low concentrations. Administration of arcaine (0.002-0.2 nmol), an antagonist of the N-methyl-D-aspartate (NMDA) receptor polyamine binding site, did not modify the test step-down latencies. In contrast, co-administration of arcaine and spermidine completely reversed the facilitatory effect of spermidine on the test step-down latencies. These results provide evidence that polyamines may be involved in learning and memory modulation.
authors.affiliation: Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Brazil.
authors.forename: M A
authors.initials: MA
authors.lastname: Rubin
authors.forename: R L
authors.initials: RL
authors.lastname: Boemo
authors.forename: A
authors.initials: A
authors.lastname: Jurach
authors.forename: D B
authors.initials: DB
authors.lastname: Rojas
authors.forename: G R
authors.initials: GR
authors.lastname: Zanolla
authors.forename: A D
authors.initials: AD
authors.lastname: Obregon
authors.forename: D O
authors.initials: DO
authors.lastname: Souza
authors.forename: C F
authors.initials: CF
authors.lastname: Mello
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001645:Biguanides / Q000494:pharmacology; D006624:Hippocampus / Q000502:physiology*; D007267:Injections; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013095:Spermidine / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D001645:Biguanides; C006624:arcaine; D013095:Spermidine