Drug effects on attack defense and escape in mice.

The relative specificity and potency of action of 32 neuropsychotropic drugs was assessed on attacks, defensive upright postures and escapes occurring in singly-housed male mice during interactions with non-aggressive strange males. Scopolamine was most potent in reducing attacks while apomorphine was most active in stimulating attacks. Defenses and escapes were inhibited most efficiently by pentobarbital and diazepam, while L-tryptophan was most active of the tested drugs in stimulating defenses and escapes. Aminooxyacetic acid and valproate inhibited both attack and defensive-escape behavior at relatively low doses. Inhibition of attacks by many drugs tested could be explained by anticholinergic, serotonergic or gabaergic effects while stimulation of attacks may be due to dopaminergic effects. Gabaergic drug actions seem to inhibit while serotonergic effects might stimulate defenses and escapes.