Neurons in layer III of the entorhinal cortex. A role in epileptogenesis and epilepsy?

Abstract

A preferential lesion of neurons in layer III of the entorhinal cortex (EC) is often observed in patients suffering from temporal lobe epilepsy and in several animal models of the disease. This lesion is duplicated in rats by a focal, intra-entorhinal injection of the "indirect" excitotoxin aminooxyacetic acid (AOAA), providing a model that can be used to study the mechanisms underlying seizure-induced cell death and epilepsy. Doomed neurons in the EC and in several associated limbic structures show pathological changes within hours after the AOAA injection, but GABAergic neurons in layer III of the EC are quite resistant. This pattern of neuron loss eventually results in hippocampal and entorhinal hyperexcitability. Notably, the seizure-induced death of layer III neurons in the EC can be attenuated by eliminating the prominent excitatory input from the presubiculum. Taken together, these results suggest opportunities to target parahippocampal structures for the treatment of temporal lobe epilepsy.

• Authors: R Schwarcz, T Eid, F Du
• Journal: Annals of the New York Academy of Sciences (Ann N Y Acad Sci) Vol. 911 Pg. 328-42 (Jun 2000) ISSN: 0077-8923 [Print] United States
• PMID: 10911883 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S., Review)

Chemical References

• Aminooxyacetic Acid

Topics

• Aminooxyacetic Acid
• Animals
• Entorhinal Cortex (pathology, physiopathology)
• Epilepsy (chemically induced, etiology, physiopathology)
• Injections
• Neurons (physiology)
• Neurons, Afferent (physiology)