Sex Differences in Learned Helplessness and Blood Plasma Corticosterone in a Rat Model of Sub-chronic Stress

Psychological stress affects women more when compared to men. Despite this, there are limited studies investigating stress and underlying sexual dimorphisms. Therefore, our objectives were 1) to determine whether there are any sex differences in immobile behavior (a measure of learned helplessness) during the forced swim test (FST; a model of sub-chronic stress), and 2) to compare corticosterone levels in male vs female rats. Immobility times were measured after exposing all rats to FST or sham conditions. All rats were sacrificed, and blood was then collected. Plasma corticosterone levels were analyzed via ELISA. Our results indicate that after exposure to the FST, immobility time increases in males and females. However, females have greater immobility times. Our preliminary data indicates similar corticosterone levels. Altogether, we can conclude that male and female rats are stressed after FST exposure, however, female rats are stressed to a greater degree when compared to male rats.

Presented at the 2021 Student Creative Arts and Research Symposium