Influence of hippocampal low-frequency stimulation on GABAA R α1, ICER and BNDF expression level in brain tissues of amygdala-kindled drug-resistant temporal lobe epileptic rats

This study investigated the therapeutic effect of hippocampal low-frequency stimulation (Hip-LFS) and its influence on the type A γ-aminobutyric acid receptor α1 subunit (GABAA R α1 subunit), inducible cAMP early repressor (ICER) and brain-derived neurotrophic factors (BNDF). The model of epilepsy was induced by chronic electrical stimulation in amygdala. Drug-resistant and drug-sensitive epileptic rats were selected by testing their seizure response to phenytoin and phenobarbital. The changes of GABAA R α1 subunit, ICER and BDNF expression were detected via immunohistochemistry and western blot. The expression levels of ICER and BDNF were increased remarkably but the GABAA R α1 subunit decreased significantly in the drug-resistant epileptic rats. However, the expression levels of ICER, BDNF were decreased and the expression of the GABAA R α1 subunit increased significantly in the drug-resistant epileptic rats after two weeks of Hip-LFS. Meanwhile, the seizure degree was reduced and the electroencephalograms were improved. The present study demonstrated that increased ICER and BDNF might be associated with the development of drug-resistance. The effect of Hip-LFS in the treatment of drug-resistant epileptic rats might be associated with increasing the levels of the ICER and the BDNF.