Ontogeny of self-sustaining status epilepticus

Rat pups of ages of 20, 25, 30 and 35 postnatal days were subjected to the perforant-path stimulation model of status epilepticus (SE). This treatment resulted in age- and stimulus-frequency-dependent loss of inhibition in th e dentate granule cell layer. Only 35% of the 20-day-old animals, but 88% o f the 35-day-olds, progressed to self-sustaining status epilepticus (SSSE). Loss of inhibition as measured by 0.1-Hz paired-pulse testing and histolog ic damage that extended to the contralateral side, including both the hilus and some extrahippocampal limbic structures, were associated with SSSE. Th is model of SE differs from in vitro models of SE, in which immature animal s show an increased susceptibility to epileptogenic stimuli, and provides u s with a novel method to study epileptogenicity in the developing brain. Co pyright (C) 1999 S. Karger AG, Basel.