El mouse as a model of focal epilepsy: a review

The El mouse is a model of hereditary sensory precipitated temporal lobe epilepsy. All adult El mice given rhythmic vestibular stimulation (e.g. tossing, rocking) during development will experience tonic-clonic convulsions when given similar stimulation as adults. The seizures have prodromal, convulsive, and postictal stages. EEG and 2-deoxyglucose studies have localized the seizures to the temporal lobe, with onset in the hippocampus. El mice have a decreased threshold for convulsion by electrical or pharmacologic stimulation. A variety of anticonvulsant medications eliminate El mouse seizures, including phenytoin (PHT), phenobarbital (PB), valproate (VPA), and ethosuximide (ESM). Anatomic studies have shown subtle differences in the thalamus and hippocampus of El mice. Immunohistochemistry of the El mouse hippocampus has revealed changes in peptidergic and gabaergic cell populations. Numerous biochemical differences have been found between El and nonconvulsive mice, including increased acetylcholine (ACh), dopamine (DA), GABA, serotonin (5-HT), and decreased norepinephrine (NE).