抄録
Focal and generalized seizures can profoundly affect autonomic nervous system (ANS) function. Sudden death during a seizure, however, is not limited to status epilepticus or even generalized tonic-clonic seizures. We used a kainic acid model (10 mg/kg ia) to study repeated seizure activity in urethane anesthetized rats. One vagus nerve and a cervical sympathetic ganglion were each recorded with an electrode array in the neck region. Blood pressure, ECG, and hippocampal EEG were recorded. Vagus nerves were cut to prevent fatal arrhythmias. EEG power spectra (1 s epochs) were integrated in the 3-10, 10-30, and 30-100 Hz bands. Peripheral nerve activity was analyzed by integration of rectified recordings for the corresponding epochs. Individual hippocampal seizures (lasting 10 s to 1 min) were characterized by increases in all 3 EEG frequency bands (beginning in the 30-100 Hz band). We found: 1) sustained increases in firing in all nerve recordings; and 2) many seizures were associated with additional firing increases in the vagus nerve and/or the cervial sympathetic ganglion. Seizures accompanied by increased peripheral nerve firing were often interspersed with seizures that were unaccompanied by additional peripheral nerve activity. We conclude that not all seizures, even within the same animal, cause the same degree of ANS disruption. We believe this preparation will be useful for determining the factors that control spread of seizure activity from the limbic cortices to the ANS. Support: NS045160. [Jpn J Physiol 55 Suppl:S196 (2005)]
