Oral administration of guanosine impairs inhibitory avoidance performance in rats and mice.
Extracellular guanine-based purines, mainly the nucleoside guanosine, have recently been shown to exert neuroprotective effects, which seem to be related to antagonism of the glutamatergic system. In this study, we investigated the effects of acute oral administration of guanosine on inhibitory avoidance task in rats and mice. We also studied its effects on locomotor activity, anxiety-related behaviors and mechanisms of action involving the purinergic system. Guanosine (2.0 and 7.5mg/kg, per os), administered 75min pretraining, dose-dependently impaired retention of the inhibitory avoidance task in rats and mice, an effect not prevented by the adenosine receptor antagonist caffeine. Guanosine presented no effects on locomotor activity and anxiety-related behaviors. This amnesic effect of guanosine may be compatible with inhibition of glutamatergic system and seems to be not mediated by adenosine.
Department of Biochemistry, ICBS, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
Elsa Regina
ER
Vinadé
Ivan
I
Izquierdo
Diogo Rizzato
DR
Lara
André Prato
AP
Schmidt
Diogo Onofre
DO
Souza
D000284:Administration, Oral; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001522:Behavior, Animal / Q000187:drug effects; D006151:Guanosine / Q000008:administration & dosage / Q000009:adverse effects*; D007266:Inhibition, Psychological; D008297:Male; D018782:Maze Learning / Q000187:drug effects*; D051379:Mice; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors
D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate; D006151:Guanosine