Altered inhibition in the hippocampal neural networks after spreading depression

•Delayed neuronal hyperexcitability occurred after spreading depression (SD).•Hyperexcitability after SD may play a role in the mechanism of SD-related disorders.•SD enhanced the number and duration of bicuculline-induced afterdischarges.•Paired-pulse inhibition and inhibitory post synaptic potentials were reduced by SD.•GABA-mediated inhibition contributes to SD-induced delayed hyperexcitability.