Effect of Repeated Transcranial Magnetic Stimulation During Epileptogenesis on Spontaneous Activity of Hippocampal Ca1 Pyramidal Neurons in Rats

Introduction: considering the antiepileptogenic effects of repeated transcranial magnetic stimulation (rtms), the effect of rtms applied during amygdala kindling on spontaneous activity of hippocampal ca1 pyramidal neurons was investigated.materials and methods: a tripolar electrode was inserted in basolateral amygdala of male wistar rats. after a recovery period, animals received daily kindling stimulations until they reached stage 5 seizure. in one group of animals, rtms at frequency of 1 hz were applied to hippocampus once daily at 5 min after termination of kindling stimulations. 24 h after the last kindling stimulation, spontaneous activity of ca1 pyramidal neurons of the hippocampus was investigated using whole cell patch clamp technique.results: kindling-induced seizures resulted in increment of spontaneous activity of hippocampal ca1 neurons, but application of rtms during amygdala kindling prevented it. moreover, rtms administration inhibited the kindling-induced enhancement of afterdepolarization (adp) amplitude and action potential duration.conclusion: results of this study suggest that rtms exerts its anticonvulsant effect, in part, through preventing the amygdala kindling-induced increase in spontaneous activity and excitability of hippocampal ca1 pyramidal neurons.