The Effect of Chronic Mild Stress on Ethanol Self-administration in Rats

Although researchers cannot manipulate human life stress to determine the effect of depression on alcohol use, research with an animal model provides the opportunity to investigate a causal link between depression and substance abuse. Researchers developed the Chronic Mild Stress (CMS) procedure to model ongoing strains that may cause human depression. Exposure to CMS and subsequent reduction of sucrose intake is classified as a decreased response to reward, or anhedonia. The current study proposed that when exposed to CMS, subjects would decrease sucrose solution intake and either increase or decrease ethanol solution intake. After 8 weeks of exposure to stressors including paired housing, soiled cage, overnight illumination, and cage tilt, statistical analysis revealed no consumption differences between control and stressed animals. Explanations for the failure to reproduce the CMS effect include choice of rat strain, stressors used, and consumption testing method