[The effects of valtrate on the EEG of the isolated, perfused rat brain].

The purpose of the present investigation was to prove the central activity of valtrate. In order to avoid biotransformation of valtrate the isolated perfused rat brain was used for this study. The CNS activity of the drug was characterized by EEG changes which were analysed visually and quantified by automatic methods. The following results were obtained: In the EEG of brains perfused with valtrate the normal background beta activity was interrupted by spikes and paroxysmal patterns of theta frequencies. These patterns disappeared after reperfusion with the control medium without drug. Valtrate reduced the beta activity and produced an increase in the theta and delta frequencies of the EEG. Using valtrate concentrations of 0.1-100 mumol/l in the perfusion medium a clear dose-response relationship was not demonstrable.