Animal models for mesiotemporal lobe epilepsy: The end of a misunderstanding?

The fact that epilepsy consists in multiple heterogeneous syndromes with different etiologies and different symptoms is insufficiently taken into account in current animal models. This is in particular the case when modeling mesiotemporal lobe epilepsy (MTLE) for which clinical, electrophysiological, histological and pharmacological features have been well described in the clinic but only partially reproduced in most rodent models. In this review, we report the data of our recent survey of european neurologists with expertise in epilepsy. The answers of 82 of them (out of 258) indicated that seizures with mild behavioral signs, hippocampal sclerosis and focal discharges were the three most critical features to be considered when developing an animal model of MTLE. We then examined how these features are reproduced in three different types of animal models of MTLE depending on their induction: (i) generalized convulsive status epilepticus; (ii) hyperthermic seizures in immature animals and (iii) focal status epilepticus. Among them, only rodent models resulting from the induction of a focal status epilepticus appear to present most characteristics of human MTLE.