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The pilocarpine model of epilepsy

  • Cavalheiro E. A. 
Animal Models Relevant to Human Epilepsies

Abstract

The systemic administration of a potent muscarinic agonist pilocarpine in rats promotes sequential behavioural and electrographic changes that can be divided in three distinct periods: (a) an acute period that built up progressively into a limbic status epilepticus and that lasts 24h, (b) a silent period with a progressive normalization of EEG and behaviour which varies from 4 to 44 days, and (c) a chronic period with spontaneous recurrent seizures (SRSs). The main features of the SRSs observed during the long-term period resemble those of human complex partial seizures and recurs 2–3 times per week per animal. Therefore, this novel and unique experimental approach may serve as a model of epilepsy mimicking the human condition.

Key Words

pilocarpine status epilepticus limbic epilepsy, rats 

Sommario

La somministrazione sistemica nei ratti di pilocarpina, un potente agonista muscarinico, determina modificationi sequenziali sul piano comportamentale ed elettrografico che possono essere divisi in tre periodi distinti: a) un periodo acuto che determina progressivamente uno stato epilettico a livello limbico che dura 24 h; b) un periodo silente con una progressiva normalizzazione dell'EEG e dello stato comportamentale che varia da 4 a 44 giorni; c) un periodo cronico caratterizzato da crisi spontanee ricorrenti (SRSs). Le principali caratteristiche dell'SRSs osservate sul lungo periodo sono simili a quelle che si riscontrano nelle crisi parziali complesse umane e ricorrono in ogni animale con una frequenza di 2–3 volte alla settimana. Pertanto, questo nuovo ed unico approccio sperimentale può essere utilizzato come modello di epilessia che mima la condizione patologica umana.

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Copyright information

© Masson Italia Periodici S.r.l. 1995

Authors and Affiliations

  • Cavalheiro E. A. 
    • 1
  1. 1.Neurologia ExperimentalEscola Paulista de MedicinaSão PauloBrasil

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