Influence of lamotrigine on histological hippocampal changes in rats with kainic acid-induced seizures

The aim of the present study was to investigate the histological changes in the hippocampus of rats with kainic acid (KA)-induced convulsions and the influence of lamotrigine (LTG) in the prevention of hippocampal neuronal brain damage. The study was carried out on Hanover-Wistar rats. The histopathological changes of hippocampal CA1 region, as a number of normal (undamaged) cells per mm of CA1 pyramidal layer, were determined two hours and five days after a single subcutaneous KA injection (8 mg/kg). LTG (30 mg/kg) was administered two hours before KA application and during five consecutive days. The histological analysis was also performed two hours and five days after KA application. The number of CA1 cells was significantly (P<0.05) lower in all groups of rats treated with KA (2 hours and five days after KA administration) compared to controlled animals (173.6+/- 4.12 cells/mm). The number of damaged/dead cells was significantly less pronounced in LTG pre-treated rats (122.9+/-7.9) than in untreated animals (94.6+/- 7.95) on the fifth day. The systemic application of KA causes extensive disturbances in the density, structure and integrity of CA1 hippocampal pyramidal cells while LTG pre-treatment significantly reduced neuronal damage level.