Myelin damage of hippocampus and cerebral cortex in rat pentylenetetrazol model

Epilepsy is a chronic neurological disorder characterized by spontaneous recurrent seizures, which also occur in demyelinating diseases of the central nervous system (CNS) with a higher prevalence. Meanwhile, demyelination occurrings have been occasionally observed in CNS of epilepsy patients, indicating an association between demyelination and epileptic seizures by an unknown mechanism. However, no confirmative experimental evidence has yet been given. Thus, by using a rat pentylenetetrazol model, electroencephalogram (EEG), Western blotting, enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, the present study provided direct evidence that myelin sheath damage in rat hippocampus and cerebral cortex started in the early stage of epileptic seizures induction and lasted with no further increase in severity in the development of epileptic seizures. It was illustrated that myelin sheath damage was not the result of oligodendrocyte destruction, but the autoantibodies against myelin basic protein (MBP) produced in peripheral circulation accompanied by increased permeability of blood-brain barrier (BBB) formed in the development of epileptic seizures. This study firstly provided experimental evidence for myelin sheath damage in PTZ-induced rat's epileptic seizures and further demonstrated that its possible cause was autoimmunoreaction.