Hippocampal cell loss and propagation of abnormal discharges accompanied with the expression of tonic convulsion in the spontaneously epileptic rat

Abstract Spontaneously epileptic rats (SER) are double mutants with both tonic convulsion and absence-like seizures from the age of 8 weeks. Hippocampal CA3 neurons in SER display a long-lasting depolarizing shift accompanied by repetitive firing (attributed to abnormalities of the Ca 2+ channels) with a single stimulation of the mossy fibers. In the present investigation, we examined if the seizure discharges of SER were correlated with the hippocampal abnormality of SER using electrophysiological and histological methods. In CA1 neurons of seizure-susceptible mature SER, higher-voltage ( p