FIG. 3.

Quantification of stimulus train–induced electrographic seizure activity in hippocampal–entorhinal cortical slices prepared from 21- to 30-day-old control (A), 60- to 120-day-old control (B), brain-injured (C), and epileptic (D) animals. The graphs present a plot of Schaeffer collateral stimulus train number versus the duration of the afterdischarge elicited by the train. Recordings were stopped after 30 min of continuous electrographic seizure activity was triggered, representing the ceiling of activity duration (1,800 s). The status epilepticus (SE)-like discharges were triggered the earliest in the epileptic slices. The brain-injured slices also elicited prolonged discharges much earlier than the 21- to 30-day-old slices. The age-matched control slices (60–120 days old) for the brain-injured and epileptic animals did not develop SE. This demonstrates the marked effect of pilocarpine-induced SE and brain injury on the susceptibility of developing SE. The data give the means and standard errors of the afterdischarge duration in seconds.