Spontaneous epileptic rats show changes in sleep architecture and hypothalamic pathology.

PURPOSE

The goal of the present study was to investigate the relationship between sleep, hypothalamic pathology, and seizures in spontaneous epileptic rats.

METHODS

Rats were implanted with radiotelemetry transmitters for measuring electrocorticogram (ECoG) and stimulation electrodes in the hippocampus. Epileptogenesis was triggered by 2 h of electical stimulation-induced self-sustained status epilepticus (SSSE). After SSSE, ECoGs were monitored over a 15-week period for the occurrence of interictal high-amplitude low-frequency (HALF) acitvity and spontaneous reoccurring seizures (SRSs).

RESULTS

Spontaneous epileptic rats showed clinical features of temporal lobe epilepsy (TLE), such as spontaneous seizures, interictal activity and neuronal cell loss in the dorsomedial hypothalamus, a region important for normal sleep regulation. Interestingly, epileptic rats showed disturbances in sleep architecture, with a high percentage of the seizures occurring during sleep.

CONCLUSIONS

Therefore we conclude that a close association exists between epileptiform activity and alterations in sleep architecture that may be related to hypothalamic pathology.