Modification of local neuronal interactions by amygdala kindling examined in vitro.

Stimulation of the amygdala in coronal slices of the amygdala-pyriform region elicited burst responses in the pyriform cortex cells. The burst responses, recorded intracellularly, consisted of a train of action potentials riding on a depolarizing envelope that lasted for an average of 0.4 s. When a similar stimulus was applied to slices prepared from rats previously subjected to amygdala kindling, burst responses were significantly prolonged (average of 6.6 s). Our results indicate that the increased excitability of the chronic epileptic site developed in vivo was retained in the excised amygdala-pyriform slice.