Study of Epileptiform Discharges in Hippocampal Slices Using Multi-Channel Recording System

Understanding the initiation site and propagation of epileptiform discharges in hippocampus are of important physiological significance. Here in transverse plane of hippocampus, the above questions were investigated with low-Mg
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ACSF perfused hippocampal slices of Sprague Dawley rat using microelectrode arrays. Initiation site of epileptiform discharges was determined by comparing the onset time of field potentials as well as calculating the cross-correlation of multiunit action potentials. Time delay of epileptiform discharges between the initiation site and the other regions was obtained. The result indicates that epileptiform discharges originate from CA3b region and propagate to CA3c and proximal CA1 respectively.