Systemic administration of polyaminergic agents modulate fear conditioning in rats.
BACKGROUND
The polyamines putrescine, spermine, and spermidine are a group of aliphatic amines that physiologically modulate the N-methyl-D-aspartate (NMDA) receptor, a glutamate receptor implicated in memory formation.


OBJECTIVE
Given the potential application of these drugs in the treatment of memory disorders, we investigated whether agonists and/or antagonists of the NMDA receptor polyamine binding site alters the memory of fear conditioning and determined the time window in which fear conditioning is modulated by polyaminergic agents given by the systemic route.


RESULTS
Post-training intraperitoneal administration of spermidine (10-100 mg/kg) immediately after training increased, whereas arcaine (10 mg/kg) and MK-801 (0.01-0.1 mg/kg) decreased contextual and auditory fear conditioning. Arcaine and MK-801, at doses that had no effect per se, reversed the facilitatory effect of spermidine. Memory of fear conditioning was impaired by polyaminergic blockade up to 180 min but not at 360 min after training.


CONCLUSIONS
These results provide evidence that systemic administration of polyamine binding site ligands modulate early consolidation of fear conditioning.
Camera
Keli
K
Laboratório de Neurotoxicidade e Psicofarmacologia, Centro de Ciências Naturais e Exatas, Departamento de Química, Universidade Federal de Santa Maria, Santa Maria, 97105-900 RS, Brazil.
Mello
Carlos Fernando
CF
Ceretta
Ana Paula Chiapinotto
AP
Rubin
Maribel Antonello
MA
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001645:Biguanides / Q000008:administration & dosage / Q000494:pharmacology*; D003214:Conditioning, Classical / Q000187:drug effects*; D016291:Dizocilpine Maleate / Q000008:administration & dosage / Q000494:pharmacology*; D005239:Fear / Q000187:drug effects* / Q000502:physiology; D007274:Injections, Intraperitoneal; D008297:Male; D008568:Memory / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000819:agonists / Q000037:antagonists & inhibitors; D013095:Spermidine / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors
D001645:Biguanides; D016194:Receptors, N-Methyl-D-Aspartate; C006624:arcaine; D016291:Dizocilpine Maleate; D013095:Spermidine