Effects of new benzodiazepine estazolam on ECOG pattern and maximal electroshock (MES) in the rat

As described previously benzodiazepines produced a concomitant increase of slow and fast waves, as well as of spindle activity different from those observed by barbiturates. In our experiments, occurrence of slow waves after estazolam preceded the induction of fast waves. The mode of action of estazolam seems to be strongly dose-dependent. dependent. In lower doses estazolam produced synchronization of the ECoG (lowering the frequency and increasing both the voltage level and spindle activity). On the contrary, in higher doses estazolam (except the first 15-20 min. after administration) produced fast activity in the ECoG (decreasing both the voltage level and spindle activity). It might be concluded that at the higher doses the mode of action of estazolam is similar to the action of diazepam, and at lower doses to flunitrazepam and clonazepam.