Antidepressant treatment and rodent aggressive behaviour.

This review examines two 'ethologically relevant' rodent models, the resident-intruder and social hierarchy paradigms, that are sensitive to chronic antidepressant treatment (including repeated electroconvulsive shock). These models of rodent social and agonistic behaviour demonstrate that acute and chronic treatment with antidepressant drugs (regardless of their acute pharmacological activity) induce diametrically opposite changes in rodent aggressive behaviour. The common ability of chronic antidepressant treatment to increase rodent aggression (which in turn results in increased hierarchical status in closed social groups) most likely reflects the increased assertiveness and associated externalization of emotions (indicative of increased extrapunitive aggression) expressed during recovery from depressive illness.