Aminooxyacetic acid causes selective neuronal loss in layer III of the rat medial entorhinal cortex

Abstract

Aminooxyacetic acid (AOAA) was used to produce a selective lesion in the rat entorhinal cortex (EC). As assessed 7 days following the injection of AOAA (75 μg0.75 μl) into the EC, neuronal loss in layer III of the medial EC, particularly in its ventral portion, was consistently observed in Nissl-stained horizontal sections. This selective neurodegeneration was seen even when AOAA was injected laterally or in deeper layers. Behavioral seizures occurred between 2 and 4 h after the AOAA injection. AOAA-induced EC lesions may provide experimental models for the study of human diseases in which the EC, particularly layer III neurons, is involved.