Lewis and Fischer 344 rats as a model for genetic differences in spatial learning and memory: Cocaine effects.
Prog Neuropsychopharmacol Biol Psychiatry
; 76: 49-57, 2017 06 02.
Article
em En
| MEDLINE
| ID: mdl-28263897
ABSTRACT
Lewis (LEW) and Fischer 344 (F344) rats are considered a model of genetic vulnerability to drug addiction. We previously showed important differences in spatial learning and memory between them, but in contrast with previous experiments demonstrating cocaine-induced enhanced learning in Morris water maze (MWM) highly demanding tasks, the eight-arm radial maze (RAM) performance was not modified either in LEW or F344 rats after chronic cocaine treatment. In the present work, chronically cocaine-treated LEW and F344 adult rats have been evaluated in learning and memory performance using the Y-maze, two RAM protocols that differ in difficulty, and a reversal protocol that tests cognitive flexibility. After one of the RAM protocols, we quantified dendritic spine density in hippocampal CA1 neurons and compared it to animals treated with cocaine but not submitted to RAM. LEW cocaine treated rats showed a better performance in the Y maze than their saline counterparts, an effect that was not evident in the F344 strain. F344 rats significantly took more time to learn the RAM task and made a greater number of errors than LEW animals in both protocols tested, whereas cocaine treatment induced deleterious effects in learning and memory in the highly difficult protocol. Moreover, hippocampal spine density was cocaine-modulated in LEW animals whereas no effects were found in F344 rats. We propose that differences in addictive-like behavior between LEW and F344 rats could be related to differences in hippocampal learning and memory processes that could be on the basis of individual vulnerability to cocaine addiction.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Comportamento Animal
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Cocaína
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Aprendizagem em Labirinto
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Inibidores da Captação de Dopamina
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Modelos Animais
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Espinhas Dendríticas
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Região CA1 Hipocampal
Tipo de estudo:
Guideline
Limite:
Animals
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article