Prenatal Stress in Rats and its Effects on Serum Corticosterone Levels

Prenatal stress is known to affect a variety of measures of stress in mature offspring, including corticosterone. The purpose of this experiment is to examine the effects of unpredictable, chronic prenatal stress on serum corticosterone levels, both at rest and in response to an acute stressor. Pregnant dams were stressed over the course of the final week of gestation using an unpredictable schedule of a variety of stressors. Offspring were exposed to foot shocks and trunk blood was collected, then analyzed by ELISA for corticosterone concentration. Prenatally stressed rats demonstrated both decreased baseline corticosterone and a slightly altered corticosterone release over time. From these results, we conclude that prenatal stress induces a general decrease in serum corticosterone, potentially due to increased negative feedback in the stress response system