Avaliação comparativa da expressão de c-Fos no cortex cerebral de ratos e saguis após estimulação com pentilenotetrazol

• Autor(a) principal: Magalhães, Stefani Alves [UNIFESP]
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UNIFESP
• dARK ID: ark:/48912/001300000cv6w
• Texto Completo: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=6315073; https://repositorio.unifesp.br/handle/11600/52894
• topic: C-Fos; Primates; Neuronal Activation; Stereology; C-Fos; Primatas; Ativação Neuronal; Estereologia

Introduction: Previous evidence from our laboratory indicate a potential mechanism that might support the fact that primates exhibit greater cogntive integration capacity as a result of the activation of different structures of the central nervous system, as compared to rodents. The current study might contribute to explain the different neural processing capacities presented by these animals as compared to other mammal orders. Aims: To search for stronger evidence that could confirm our previous findings here we analyzed the patterns of c-Fos expression in neocortical structures of rats and marmosets using a more robust quantitative technique and evaluating a larger number of brain areas. Twenty-seven rats (Wistar) and 21 marmosets (Callithrix jacchus) were euthanized at different times after seizures induced by the GABAergic antagonist pentylenetetrazol (PTZ), and then distributed among the control groups (animals without seizures); PTZ group 0.5h; 1, 2, 3, 6, 9 and 12h after PTZ induction. The biological material was processed for the immunohistochemical detection of c-Fos and the cell count was performed by means of the stereology technique with a StereoInvestigator® program. Results: Marmosets had a c-Fos expression that was notably stronger (5x) and longer (up to 3 hours) than rats. Yet, the expression in rats presented similar patterns of expression according to the function of the structures (associative, cortical and motor functions), which was not observed for marmosets. Conclusions: Our results provide evidence that the marmoset brain has a greater neuronal activation after intense stimulation by means of PTZ and a more complex pattern of brain activation, which are indicative of a brain structure with a higher degree of specialization than that seen for rats. Although expected, these functional differences had never been characterized before, and may contribute for the understanding of the different neuronal processing capacities of these mammals orders.