Obsessive-compulsive-like behaviors in house mice are attenuated by a probiotic (Lactobacillus rhamnosus GG)

Behav Pharmacol. 2014 Feb;25(1):71-9. doi: 10.1097/FBP.0000000000000013.


Two experiments examined probiotic pretreatment (Lactobacillus rhamnosus GG) on obsessive-compulsive disorder (OCD)-like behavior induction by RU 24969 in BALB/cJ house mice. In the first experiment, two groups were defined by their daily pretreatment by oral gavage of either (a) L. rhamnosus (1×10⁹ CFU/day) or (b) the saline vehicle. Both a 2- and 4-week probiotic pretreatment attenuated OCD-like behavior induction (increased perseverative open-field locomotion, stereotypic turning, and marble burying) relative to saline pretreatment. Experiment 2 re-examined the 2-week probiotic pretreatment while also comparing it to a 4-week fluoxetine pretreatment. Again, groups were defined by daily pretreatment of either (a) L. rhamnosus for 2 weeks, (b) the saline vehicle for 2 weeks, or (c) fluoxetine (10 mg/kg) for 4 weeks. Pretreatment by either L. rhamnosus or fluoxetine blocked the induction of OCD-like behavior compared with saline pretreatment. Thus the 2-week probiotic pretreatment was again effective. Although side effects of fluoxetine or L. rhamnosus on androgen-dependent behaviors could not be demonstrated, L. rhamnosus treatment appeared comparable to fluoxetine treatment in attenuating mouse OCD-like behaviors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antidepressive Agents, Second-Generation / therapeutic use
  • Dietary Supplements*
  • Disease Models, Animal
  • Exploratory Behavior / drug effects
  • Fluoxetine / therapeutic use
  • Freeze Drying
  • Indoles / toxicity
  • Lactobacillus / chemistry
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Motor Activity / drug effects
  • Obsessive-Compulsive Disorder / chemically induced
  • Obsessive-Compulsive Disorder / drug therapy*
  • Probiotics / therapeutic use*
  • Serotonin Receptor Agonists / toxicity
  • Social Behavior
  • Time Factors
  • Vocalization, Animal / drug effects


  • Antidepressive Agents, Second-Generation
  • Indoles
  • Serotonin Receptor Agonists
  • Fluoxetine
  • 5-methoxy 3-(1,2,3,6-tetrahydro-4-pyridinyl)1H indole