The modified 2VO ischemia protocol causes cognitive impairment similar to that induced by the standard method, but with a better survival rate

Permanent bilateral occlusion of the common carotid arteries (2VO) in the rat has been established as a valid experimental model to investigate the effects of chronic cerebral hypoperfusion on cognitive function and neurodegenerative processes. Our aim was to compare the cognitive and morphological...

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Detalhes bibliográficos
Autores: Cechetti, Fernanda, Worm, Paulo Valdeci, Silva, Lenir Orlandi Pereira, Siqueira, Ionara Rodrigues, Netto, Carlos Alexandre
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2010
País:Brasil
Recursos:Universidade Federal do Rio Grande do Sul (UFRGS)
Repositório:Repositório Institucional da UFRGS
Idioma:inglês
OAI Identifier:oai:www.lume.ufrgs.br:10183/30588
Acesso em linha:http://hdl.handle.net/10183/30588
Access Level:Acceso aberto
Palavra-chave:Memória
Hipocampo
Hipoperfusão crônica
Chronic cerebral hypoperfusion
Spatial memory
Hippocampus
Striatum
Water maze
Descrição
Resumo:Permanent bilateral occlusion of the common carotid arteries (2VO) in the rat has been established as a valid experimental model to investigate the effects of chronic cerebral hypoperfusion on cognitive function and neurodegenerative processes. Our aim was to compare the cognitive and morphological outcomes following the standard 2VO procedure, in which there is concomitant artery ligation, with those of a modified protocol, with a 1-week interval between artery occlusions to avoid an abrupt reduction of cerebral blood flow, as assessed by animal performance in the water maze and damage extension to the hippocampus and striatum. Male Wistar rats (N = 47) aged 3 months were subjected to chronic hypoperfusion by permanent bilateral ligation of the common carotid arteries using either the standard or the modified protocol, with the right carotid being the first to be occluded. Three months after the surgical procedure, rat performance in the water maze was assessed to investigate long-term effects on spatial learning and memory and their brains were processed in order to estimate hippocampal volume and striatal area. Both groups of hypoperfused rats showed deficits in reference (F(8,172) = 7.0951, P < 0.00001) and working spatial memory [2nd (F(2,44) = 7.6884, P < 0.001), 3rd (F(2,44) = 21.481, P < 0.00001) and 4th trials (F(2,44) = 28.620, P < 0.0001)]; however, no evidence of tissue atrophy was found in the brain structures studied. Despite similar behavioral and morphological outcomes, the rats submitted to the modified protocol showed a significant increase in survival rate, during the 3 months of the experiment (P < 0.02).