SELECTIVE FACILITATION OF KINDLED SEIZURES FROM THE AMYGDALA AFTER HIPPOCAMPAL-LESIONS INDUCED BY PERFORANT PATH STIMULATION

Intermittent electrical stimulation of the perforant path (PPS) for 24 h in anesthetized rats results in impairment of paired pulse inhibiti on, neuronal loss in the dentate gyrus and hippocampus, and delayed sp ontaneous seizures. One week after PPS, animals showed a dramatic decr ease in afterdischarge threshold and increase in afterdischarge durati on from the basolateral amygdala, whereas no changes in afterdischarge properties were observed from the dentate gyms. Animals also showed a remarkable facilitation of amygdala kindling, but not of perforant pa th kindling. After amygdala kindling, some animals showed spontaneous seizures. PPS may recruit amygdala into the epileptogenic circuit, res ulting in 'latent' kindling and development of spontaneous seizures. ( C) 1997 Elsevier Science Ireland Ltd.