Hippocampal gene network analysis in an experimental model of posttraumatic epilepsy.

In the present study, we performed comprehensive gene expression and gene network analyses using a DNA microarray to elucidate the molecular events responsible for the pathology of posttraumatic epilepsy at the partial seizure stage. We used an experimental posttraumatic epilepsy model of amygdalar focal FeCl(3)-injected rats and compared gene expression profiles in the hippocampus at the partial seizure stage (less than stage 3 on Racine's convulsion scale) and that of sham-operated animals. At the partial seizure stage, upregulation of phospholipase A2 (PLA2) and lipid metabolism were observed, which have been reported to be caused by brain injury and seizures in previous studies. Furthermore, significant upregulation of genes related to inflammation and the immune system was observed. These molecular changes in PLA2 and lipid metabolism may be related to seizure propagation.