Proteomic analysis of rats submitted to the animal model of epilepsy induced by pilocarpine.

Background and Purpose: The temporal lobe epilepsy (TLE) is the most common type of partial complex seizure in adulthood. High doses of pilocarpine to rats induce status epilepticus (SE) and reproduce the main characteristics of TLE. This model appears to be highly isomorphic with the human disease, so it has been used to elucidate the main mechanisms involved with epileptogenesis. Methods: Here, we employed a two-dimensional gel electrophoresis (2-DE) to study differential expression of proteins in the hippocampus of rats exhibiting SRS induced by pilocarpine (360mg/kg, N=6) compared to a control group (saline, N=6). Both groups were analyzed 90 days after SE onset. Hippocampi were homogenized in a lysis buffer and used to perform 2-DE. Protein spots analyzed by PDQuest software and identified by LC-ESI-MS/MS and MASCOT MS/MS ions search. Results: forty proteins were found differentially expressed in the hippocampus of epileptic rats compared to control animals from which thirty-seven were successfully identified. Twenty-nine of the identified proteins were up-regulated in epileptic rats while six proteins were down-regulated and two proteins were expressed only in the control animals. Conclusion: Some of the proteins differentially expressed in the hippocampus of rats with SRS were also observed altered in the hippocampus of patients with TLE. Such proteins are part of metabolic pathways responsible for the maintenance of vital functions for the cell. Besides, proteins potentially involved in neuronal development and plasticity, neuroprotection mechanisms and neuronal excitability were also found up-regulated in epileptic rats.