An isolated, perfused rat brain preparation, its spontaneous and stimulated activity.

Abstract

A simple isolated, perfused rat brain preparation has been developed. The surgical procedure can be performed by a single operator without assistance in approximately 1 hr. The preparation consists of the completely detached skull and its contents from which the extracranial structures have been removed. It was prepared from a rat anesthetized by deep hypothermia without any chemical agent. The preparation was perfused with an artificial blood by means of a small roller-type pump and an oxygenator. These isolated brain preparations had spontaneous electroencephalographic (EEG) activity which persisted as long as 5 hr with open-circuit perfusion and about 2 hr on perfusion with recircula-tion. Addition of pentylenetetrazol (Metrazol) to the perfusing blood evoked characteristic EEG signs of convulsive activity either before or after spontaneous EEG activity had ceased. The preparation showed an EEG response to loud sound which bore some resumblance to the response to Metrazol. Glucose was consumed at a linear rate during the period of spontaneous EEG and considerable amounts of lactate accumulated in the perfusing blood.