Participação dos receptores histaminérgicos na consolidação da memória de reconhecimento de objetos em ratos

• Ano de defesa: 2011
• Autor(a) principal: Silveira, Clarice Krás Borges da
• Orientador(a): Izquierdo, Ivan Antônio
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul; Porto Alegre
• Palavras-chave em Português: MEDICINA; NEUROCIÊNCIA; MEMÓRIA; HISTAMINA; RECEPTORES DE HISTAMINA; HIPOCAMPO; RATOS - EXPERIÊNCIAS
• Link de acesso: http://hdl.handle.net/10923/4566

The histamine system of the brain has been implicated in both arousal and reinforcement. Previous evidence from our laboratory has shown that histamine receptors located into the hippocampus modulate learning and memory on the fear extinction and aversive processes. Therefore, to determine the role of hippocampal histaminergic receptors on recognition memory, adult male Wistar rats with infusion cannulae stereotaxically aimed to the CA1 region of dorsal hippocampus were trained in an object recognition learning task involving exposure to two different stimulus objects. Immediately, 30, 120 or 360 min after training, they received (1μl/side) agonist and antagonist from histamine receptors. Memory retention was assessed 24 hours after training. In the test session, one of the objects presented during training was replaced by a novel one. When infused in the CA1 region the ranitidine, H2 receptor antagonist, and imetit, H3 receptor agonist, blocked long-term memory retention in a time-,dose-dependent manner (30 to 120 min) without affecting exploratory behavior, anxiety state or the functionality of the hippocampus. Our data indicate that histaminergic system is involved in consolidation of object recognition memory.