Histamina Hipocampal, Aprendizagem e Memória
Data
2010
Autores
Goulart, Carolina de Souza 
Orientadores
Medalha, Carla Christina
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A neuroplasticidade é a capacidade do SNC de alterar a sua estrutura com base nas
experiências, responsável pelo mecanismo de aprendizagem. Estudos sugerem que
drogas e neurotransmissores que participam dos processos de memória e
aprendizagem são de fundamental importância para o entendimento do processo de
recuperação após lesão de SNC. O presente estudo visa analisar as ações do
sistema histaminérgico hipocampal sobre os processos de aquisição e consolidação
da memória, em um teste de esquiva. Ratos Wistar machos foram implantados com
cânulas nas regiões ventral e dorsal do hipocampo e treinados em um paradigma de
esquiva inibitória. O animal foi individualmente colocado na plataforma, e no
momento em que colocava as quatro patas no assoalho metálico, um choque foi
liberado nas patas por 2s (0,4 mA; 40V). O procedimento era repetido até o rato
permanecer 50s na plataforma. A latência de descida foi registrada e imediatamente
após o treino os grupos de animais receberam o tratamento com histamina, salina
(controle), coinfusão de histamina e antagonistas antagonistas receptores H1
(Pirilamina; 10,0 nmol/região) e H2 (Ranitidina; 20,0 nmol/região) no hipocampo
dorsal ou ventral. Após 24 horas foi feito o teste no qual a evocação da memória foi
testada por meio da repetição do procedimento de esquiva. A retenção da memória
foi verificada através da latência, em segundos, do treino e do teste do animal da
caixa de esquiva. Foi encontrado que a redução da atividade histaminérgica no
hipocampo ventral, a partir da injeção intra de ranitidina foi capaz de reverter à
tendência a extinção de memória aversiva propiciada pela histamina
Neuroplasticity is the ability of the CNS to alter its structure based on experience, it is responsible for the learning mechanism. Studies suggest that drugs and neurotransmitters that participate in learning and memory are of fundamental importance for understanding the recovery process after CNS injury. This study aims to examine the actions of the hippocampal histaminergic system on the processes of acquisition and memory consolidation in an avoidance test. Wistar rats were surgically canullaed in ventral and dorsal hippocampus and trained in an avoidance test. The animals were individually placed on the platform and, when they put their four legs on the metal floor, a shock was released in the legs by 2s (0.4 mA, 40V). The procedure was repeated until the rat remain 50s on the platform. The latency was recorded immediately after training and the groups of animals received treatment with their respective drugs: histamine, saline (control), coinfusão histamine H1 receptor antagonists and antagonists (pyrilamine, 10.0 nmol / region) and H2 (ranitidine, 20,0 nmol / region) in the dorsal or ventral hippocampus. 24h later, the test were performed by the procedure repetition without any shock delivery. Memory retention was measured by the latency in seconds of training and testing the animal's box avoidance. It was found that the reduction of histaminergic activity in the ventral hippocampus, from intrahippocampal injection of ranitidine was able to reverse the trend toward extinction of aversive memory afforded by histamine
Neuroplasticity is the ability of the CNS to alter its structure based on experience, it is responsible for the learning mechanism. Studies suggest that drugs and neurotransmitters that participate in learning and memory are of fundamental importance for understanding the recovery process after CNS injury. This study aims to examine the actions of the hippocampal histaminergic system on the processes of acquisition and memory consolidation in an avoidance test. Wistar rats were surgically canullaed in ventral and dorsal hippocampus and trained in an avoidance test. The animals were individually placed on the platform and, when they put their four legs on the metal floor, a shock was released in the legs by 2s (0.4 mA, 40V). The procedure was repeated until the rat remain 50s on the platform. The latency was recorded immediately after training and the groups of animals received treatment with their respective drugs: histamine, saline (control), coinfusão histamine H1 receptor antagonists and antagonists (pyrilamine, 10.0 nmol / region) and H2 (ranitidine, 20,0 nmol / region) in the dorsal or ventral hippocampus. 24h later, the test were performed by the procedure repetition without any shock delivery. Memory retention was measured by the latency in seconds of training and testing the animal's box avoidance. It was found that the reduction of histaminergic activity in the ventral hippocampus, from intrahippocampal injection of ranitidine was able to reverse the trend toward extinction of aversive memory afforded by histamine
Descrição
Citação
GOULART, Carolina de Souza. Histamina Hipocampal, Aprendizagem e Memória. 2010. 27 f. Trabalho de conclusão de curso de graduação (Fisioterapia) - Instituto de Saúde e Sociedade (ISS), Universidade Federal de São Paulo (UNIFESP), Santos, 2010.