Melatonin administration after pilocarpine-induced status epilepticus: A new way to prevent or attenuate postlesion epilepsy?

Objective: The goal of this study was to verify the effects of treatment with melatonin and N-acetylserotonin on the pilocarpine-induced epilepsy model. Methods: The animals were divided into four groups: (1) animals treated with saline (Saline); (2) animals that received pilocarpine and exhibited SE (SE); (3) animals that exhibited SE and were treated with N-acetylserotonin (30 minutes and 1, 2, 4, 6, 12, 24, 36, and 48 hours) alter SE onset (SE + NAS); (4) animals that exhibited SE and were treated with melatonin at the same time the SE + NAS group (SE + MEL). Behavioral (latency to first seizure, frequency of seizures, and mortality) and histological (Nissl and neo-Timm) parameters were analyzed. Results: The animals treated with melatonin (SE + MEL) had a decreased number of spontaneous seizures during the chronic period (P<0.05), a reduction in mossy fiber sprouting, and less cell damage than the SE group. Animals treated with N-acetylserotonin did not exhibit any kind of significant change. Conclusion: Melatonin exerts an important neuroprotective effect by attenuating SE-induced postlesion and promoting a decrease in the number of seizures in epileptic rats. This suggests, for the first time, that melatonin could be used co-therapeutically in treatment of patients exhibiting SE to minimize associated injuries in these situations. (C) 2011 Published by Elsevier Inc.