Comparison of kindling at short interstimulus intervals in acutely and chronically prepared rabbits

For the purpose of contributing methodologically to experimental research on epilepsy, we investigated whether a difference exists in kindling development between acute and chronic preparations using identical species of animals, kindled brain tissues, stimulus intervals, and intensities. Seizure-threshold stimulations repeatedly applied at 5-min intervals to the unilateral visual cortex in rabbits completed the generalization of epileptiform discharge trains after the 11th-24th trials in the acute preparations concomitantly with an increase in the afterdischarge duration and the development of independent discharges, whereas they induced no kindling phenomena even with 50 trials in the chronic preparations. These results indicate that there is an extreme difference in kindling susceptibility between acute and chronic preparations, resulting, presumably, from multifactorial dissimilarities in these experimental conditions.