Prevalence of Epileptic Seizures along the Wakefulness-Sleep Cycle in Adult Rats Submitted to Status epilepticus in Early Life

In 70 adult Wistar rats submitted to pilocarpine-induced status epilepticus in early life the electro-oscillograms were recorded from neocortical areas 10, 3 and 17, from CA1 and CA3 hippocampal fields and, in 10 rats, also from the ventrolateral nuclei and amygdala. Head, eye, rostrum + vibrissae, ear and forelimb movements were recorded as well. Fifty rats were subjected to 4-hour daily recording sessions and 20 to continuous 24-hour recordings. In all the rats spike-wave discharges (SWD) were found in every site from which the electro-oscillograms were recorded, and clonic seizures were also displayed by all the animals. Most seizures (83.75%, mean = 6.59 fits/h) were concentrated in nearly 9 h and 16.25% (mean = 0.77 fits/h) in the remaining 15 h. Eye movements occurred during 49.2% of the total duration of motor events, the head moved in 42.8% and the rostrum + vibrissae in 8.1% of the time, departing from normal rats. Therefore, pilocarpine-induced status epilepticus produces striking changes in the wakefulness-sleep cycle characteristics.