Abstract
The Perirhinal Cortex and the Seizure Generalization of Kindling in the Cat Akihisa Orita It has recently been demonstrated that the perirhinal cortex (PRC) is an impor-tant site for the generalization of kindled seizures.In this study, we observed charac-teristics of afterdischarges (ADs) in the PRC during amygdala kindling as well as the characteristics of the primary PRC kindling. PRC produced apparent ADs during the early stage of amygdala kindling. ADs were most predominant in PRC in the contralateral hemisphere when the animals showed stage 3 motor seizures.Analysis of interictal discharges (IIDs) revealed that there are four patterns in the distribution of IIDs. Only PRC always showed IIDs in every IID pattern. The development of motor seizures and ADs in the primary PRC kindling demonstrated that PRC kindling-induced epileptic activity was propagated first to the hippocampus, followed by the neocortex and then the amygdala before the full-down seizures. PRC kindled seizures were stably reproducible after the completion of kindling. These results suggest that PRC appears to be important for the seizure generalization of amygdala kindling. The development of PRC kindling is similar to that of neocortical kindling, although the stability of fully-developed seizures indicated that it is more similar to seizures from the limbic sites, suggesting that PRC kindling has characteristics from both neocor-tical and limbic kindling.
