Long-term memory modulation by posttraining epinephrine in rats: differential effects depending on the basic learning capacity.
Effects of posttraining epinephrine on retention of a massed (1 session, 30 trials) 2-way active avoidance task were studied in rats. Immediately after the training session rats received an injection of 0.05 or 0.01 mg/kg ip epinephrine, or distilled water. Retention was tested 11, 20, or 45 days after training, in independent groups of rats. The 20- and 45-day retention was improved in poor-learning rats and disrupted in good-learning rats. It was concluded that the effect (facilitatory or disruptive) of posttraining epinephrine on memory consolidation depends on the basic learning capacity of rats for this task and needs a long time to be expressed.
Torras-Garcia
M
M
Departament de Psicobiologia i Metodologia de les Ciènces de la Salut,Universitat Autònoma de Barcelona, Spain.
Portell-Cortés
I
I
Costa-Miserachs
D
D
Morgado-Bernal
I
I
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001921:Brain / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004837:Epinephrine / Q000494:pharmacology*; D007274:Injections, Intraperitoneal; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012153:Retention, Psychology / Q000187:drug effects*
D004837:Epinephrine