The effects of L. rhamnosus consumption on rat anxiety-like behavior


The effects of L. rhamnosus consumption on rat anxiety-like behavior



Amanda Marie Schleper



Adolescent stress in humans has been correlated with an increased likelihood of an adult individual to develop addictive behaviors, such as an alcohol use disorder. Literature has demonstrated that rats subjected to adolescent stress tend to show an increased ethanol consumption. Adolescence is a critical time of development and the link between adolescent stressors and alcohol use disorders is not fully understood yet. This study examined the relationship between adolescent stress and alcohol consumption in rats. Probiotics are bacteria with potential health benefits and have been well accepted as a dietary supplement. Literature shows that probiotics could decrease rodent anxiety-like behaviors derived from adolescent stress, such as social isolation. A previous study conducted at the University of Dayton showed that group housed rats that received probiotics exhibited increased anxiety-like behavior. This finding contradicts the positive perception associated with probiotics, showing that probiotics may have a negative impact on affective behaviors. Following two measures of anxiety-like behavior in rats, the Elevated Plus Maze and the Light/Dark Box, we did not find any significant differences between the chronically stressed and the control rats. Additionally, we did not find a difference between the groups in terms of alcohol consumption or preference. Lastly, this study did observe the same trend as our previous study in regards to the anxiety-like behavior demonstrated in the group housed probiotic group. We found that the group housed rats that consumed probiotics showed an increase in anxiety-like behavior. This trend did not include a significant difference between the groups, but was similar to what we observed previously. Moving forward, further research should be done to understand the potential benefits and risks of probiotics.

Publication Date


Project Designation

Honors Thesis

Primary Advisor

Tracy R. Butler, Yvonne Y. Sun

Primary Advisor's Department



Stander Symposium project

The effects of L. rhamnosus consumption on rat anxiety-like behavior