Corticosterone Increases Depression-Like Behavior, With Some Effects on Predator Odor-Induced Defensive Behavior, in Male and Female Rats.

It is suggested that repeated exposure to corticosterone increases depression-like behavior, with some effects on anxiety, and that male rats may be more affected than female rats by this manipulation.

Abstract

This experiment examined the effect of repeated corticosterone injections on anxiety and depression-like behavior in male and female rats. Rats received either corticosterone or vehicle injections for 21 consecutive days prior to behavioral testing in the forced swim, open-field, and predator odor tests. The corticosterone injections significantly increased depression-like behavior in the forced swim test in both male and female rats but had no significant effect on anxiety in the open-field test. In the predator odor test, the corticosterone injections significantly increased a subset of defensive behaviors in the male rats. These results suggest that repeated exposure to corticosterone increases depression-like behavior, with some effects on anxiety, and that male rats may be more affected than female rats by this manipulation.