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Previous issue date: 2012-04-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Toxoplasma gondii is a protozoan parasite that induces behavioral changes in rodents. The aim of this study was to evaluate the effect of infection by T. gondii during the chronic phase in working memory and impulsivity in rodents as well as the effect of antipsychotics to reverse any behavioral changes resulting from infection. Female Wistar rats (n = 40) were infected with 25 cysts of the strain ME-49 T. gondii after 4 months the animals were subjected to behavioral tests: tolerance to delay gratification, in which the animal must choose between two rewards, a smaller and more immediate, but delayed and the test of spontaneous alternation, in which the animal must use spatial cues to remember previously visited arms. Antipsychotic drugs were intraperitoneally administered during the testing of the behavioral experiments, the antipsychotic is haloperidol (1.5 mg / kg) administered 60 min before the start of the session and the antipsychotic clozapine (2.5 mg / kg) 30 min before. Animals infected with the parasite did not show operating deficits of memory, and motor impairment did not develop, however motor impairment was observed only in animals treated with haloperidol. It was found that administration of clozapine and haloperidol increased the percentage of alternation in infected and control groups in task switching espont?nea.N?o no distinction between control animals and infected the test of tolerance to delay gratification in relation to the percentage of choices greatest reward, during the pre-training and training, in which there is a delay of 15 s to access the great reward, however it was observed that infected animals prefer the greatest reward, when there is a delay of 30 s when compared to control group. The administration of clozapine possible that infected animals chose the greatest reward in the delay of 30 seconds during the test. These data suggest that infected mice do not exhibit deficits in working memory and that clozapine has therapeutic efficacy in improving cognitive performance of mice infected / O Toxoplasma gondii ? um protozo?rio parasito que induz altera??es comportamentais em roedores. O objetivo do presente estudo foi avaliar o efeito da infec??o pelo T.gondii durante a fase cr?nica na mem?ria operacional e na impulsividade de roedores, bem como o efeito de antipsic?ticos em reverter as eventuais altera??es comportamentais decorrentes da infec??o. Ratos wistar f?meas (n=40) foram infectadas com 25 cistos da cepa ME-49 do T. gondii, ap?s 4 meses os animais foram submetidos aos testes comportamentais: toler?ncia ao retardo de gratifica??o, na qual o animal deve escolher entre duas recompensas, uma menor imediata e uma maior, mas com retardo e o teste de altern?ncia espont?nea, na qual o animal deve utilizar pistas espaciais para recordar bra?os previamente visitados. Os antipsicoticos foram administrados via intraperitoneal durante a fase teste dos experimentos comportamentais, sendo o antipsic?tico haloperidol (1,5 mg/kg) administrado 60 min antes do inicio das sess?es e o antipsic?tico clozapina (2,5 mg/kg) 30 min antes. Os animais infectados com o parasito n?o apresentaram d?ficits de memoria operacional, e n?o desenvolveram preju?zo motor, no entanto foi observado preju?zo motor apenas nos animais tratados com haloperidol. Foi verificado que a administra??o de clozapina e haloperidol aumentou a porcentagem de alterna??o em grupos controle e infectado na tarefa de altern?ncia espont?nea.N?o existe distin??o entre animais do grupo controle e infectado no teste de toler?ncia ao retardo de gratifica??o em rela??o a porcentagem de escolhas pela maior recompensa, durante as fases de pr?-treinamento e treinamento, no qual existe um retardo de 15 s para o acesso da grande recompensa, no entanto foi verificado que animais infectados preferem a maior recompensa, quando existe um retardo de 30 s quando comparado ao grupo controle. A administra??o da clozapina possibilitou que os animais infectados escolhessem a maior recompensa, no retardo de 30s na fase teste. Estes dados sugerem que ratos infectados n?o apresentam d?ficits de mem?ria operacional e que a clozapina apresenta efic?cia terap?utica em melhorar o desempenho cognitivo de ratos infectados
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17338 |
| Date | 27 April 2012 |
| Creators | Maia, Raquel da Silveira |
| Contributors | CPF:25715330297, http://lattes.cnpq.br/1402289786010170, Queiroz, Cl?udio Marcos Teixeira de, CPF:16256304845, http://lattes.cnpq.br/3384801391828521, Alves, Nelson Torro, CPF:25060820858, http://lattes.cnpq.br/8037098495288980, Pereira J?nior, Ant?nio |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Psicobiologia, UFRN, BR, Estudos de Comportamento; Psicologia Fisiol?gica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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