Selective antagonism of isolation-induced aggression in mice by diazepam following chronic administration

Benzodiazepines are non-selective (i.e., they only inhibit aggression at doses producing concurrent neuromuscular impairment) antagonists of isolation-induced aggression in mice following acute administration. However, in the present study diazepam was shown to be a selective antagonist of fighting in isolated mice following chronic administration for 5 days. When administered chronically, selective tolerance rapidly developed to the general CNS depression produced by diazepam whereas the antifighting activity was not diminished and, in fact, tended to be enhanced following multiple drug administrations. Thus, the antagonism of fighting in isolated mice by diazepam does not appear to be due solely to general CNS depressant properties.