Inhibition by Arousal of Epilepsy Induced by Chlorambucil in Rats

IN clinical and experimental epilepsy, transient fluctuations in susceptibility to seizures have been shown to result from changes in behavioural state. For example, spontaneous electro-encephalographic (EEG) and overt behavioural signs of seizures have been reported more frequently during periods of relaxtion or sleep than during periods of alertness or arousal in epileptic patients1,2. Furthermore, sensory stimuli that produce alerting and orienting responses also interrupt seizure activity in patients3–5and in animals with various types of experimental epilepsy6–11. In addition, seizures produced in cats by subcortical application of aluminum oxide12or systemic injection of metrazol13have been interrupted by electrical stimulation of the mesencephalic reticular formation, a neural network believed to underlie behavioural and EEG arousal14.