Abordagem Experimental do Hipocampo Humano Obtido nas Cirurgias para Tratamento de Pacientes com Epilepsia Refratária a Drogas Antiepilépticas
DOI:
https://doi.org/10.34024/rnc.2000.v8.8940Palavras-chave:
Epileptogênese, hipocampo, eletrofisiologia, neuropatologiaResumo
Alguns pacientes que apresentam epilepsia refratária ao tratamento medicamentoso beneficiam-se da remoção cirúrgica do foco epileptogênico. O estudo das alterações eletrofisiológicas e neuropatológicas no tecido epiléptico humano é fundamental para a compreensão dos mecanismos fisiopatogênicos e o desenvolvimento de novas drogas antiepilépticas e outras modalidades terapêuticas. A esclerose mesial temporal, lesão responsável por cerca de 65% das epilepsias do adulto, cursa com grau elevado de intratabilidade. Nela as estruturas mediais do lobo temporal, principalmente o hipocampo, participam ativamente na gênese das descargas epileptiformes. No presente trabalho, abordaremos algumas das técnicas que estão sendo atualmente utilizadas para estudo da epileptogênese na epilepsia do lobo temporal. O tecido epiléptico obtido no centro cirúrgico de seis pacientes foi transportado ao laboratório onde foram realizados, além da análise eletrofisiológica in vitro, estudos neuropatológico e imunocitoquímico. Essas técnicas permitiram a detecção de anormalidades nos registros eletrofisiológicos sob a forma de descargas interictais e ictais in vitro. Foi verificada heterogeneidade das anormalidades epileptiformes tendo sido possível, ainda, a realização de testes de resistência a drogas antiepilépticas utilizadas no tratamento de um desses pacientes. Esses dados indicam que as anormalidades epileptogênicas no tecido humano devem ser complexas e que as mesmas podem ser avaliadas pela abordagem experimental. A compreensão das mesmas pode fornecer novas perspectivas na avaliação pré-cirúrgica e no tratamento dessa forma de epilepsia.
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Publicado: 2000-09-30
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