Chronic focal epilepsy induced by intracerebral tetanus toxin

  • Jefferys J. G. R. 
  • Borck C. 
  • Mellanby J. 
Animal Models Relevant to Human Epilepsies


A single, minute dose of tetanus toxin injected into mammalian cerebral cortex induces a chronic epileptic syndrome. Seizures lasting up to 3 minutes occur spontaneously and intermittently for several weeks to months. The cellular mechanisms of this model have been studied in detail using brain slicesin vitro. Initially the release of the inhibitory neurotransmitter, GABA, is blocked, but after 2–4 weeks, other mechanisms take over. Intrahippocampal tetanus toxin models human complex partial seizures (temporal lobe epilepsy). It results in consistent behavioural changes analogous with those seen clinically, in spite of the limited neuronal loss found in only 10–30% of rats. Treatment with carbamazepine ameliorates both the seizures and their behavioural consequences. Tetanus toxin provides a versatile and long-lasting model of focal epilepsies.

Key Words

tetanus toxin epileptic foci chronic model 


La singola iniezione di una dose minima di tossina tetanica nella corteccia cerebrale dei mammiferi induce una sindrome epilettica cronica. Le crisi di durata fino a 3 minuti si manifestano spontaneamente in modo intermittente per parecchie settimane o mesi. I meccanismi cellulari di questo modello sono stati studiati in dettaglio in sezioni di tessuto cerebrale incubatein vitro. Inizialmente il rilascio del neurotrasmettitore inibitorio, GABA, è bloccato ma dopo 2–4 settimane subentrano attivi meccanismi. L'iniezione intraippocampale di tossina tetanica riproduce le crisi parziali complesse che si osservano nelle epilessie del lobo temporale. Essa determina modificazioni comportamentali analoghe a quelle osservate in clinica, malgrado il limitato danno neuronale, presente solo nel 10–30% dei ratti. Il trattamento con carbamazepina ha un effetto favorevole sia sulle crisi che sulle loro conseguenze comportamentali. La tossina tetanica permette di ottenere un modello versatile e persistente di epilessie focali.


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Copyright information

© Masson Italia Periodici S.r.l. 1995

Authors and Affiliations

  • Jefferys J. G. R. 
    • 1
    • 2
  • Borck C. 
    • 1
    • 2
  • Mellanby J. 
    • 1
    • 2
  1. 1.Department of Physiology and BiophysicsSt. Mary's Hospital Medical School, Imperial CollegeLondon
  2. 2.Department of Experimental PsychologyUniversity of OxfordOxfordUK

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