Abstract

In cats with electrodes chronically implanted in selected nuclei of limbic, sensory and diffuse projection systems, anesthetic concentrations of enflurane (Ēthrane) induced bursts of high voltage spike activity separated by prolonged periods of interictal silence. In addition, residual behavioral and electrographie abnormalities were observed on the second postanesthetic day and they persisted for 14 to 16 days. In subsequent studies, anesthetic concentrations of enflurane augmented evoked responses to peripheral stimulation up to 500% over control levels. The relation of these electrographic effects to the anesthetic state and the possible use of enflurane as a tool in the delineation of mechanisms regulating cortical hyperexcitability are discussed.