Correlation between behavioral alterations and dopamine changes in mice experimentally infected with Toxoplasma gondii

Abstract

The mechanism of the parasite to induce alterations in host behavior is suggested due to changes in the dopaminergic system. This study aims to clarify the effects of latent toxoplasmosis on infected mice's behavior and to assess the dopamine neurotransmitter in their brains. Experimental infection with Toxoplasma gondii (T. gondii) and monitoring of behavioral alterations in mice using open field and hole-board tests were carried. Mice were sacrificed, then brains histo-pathologically and neuro-chemically assessed. Open field test revealed a decrease in locomotion in both infected mice genders, whereas the hole-board test displayed an increased level of exploration only by infected female mice. Significant changes in the dopamine concentration in the brain with regard to status of infection were detected. The results suggest an association between T. gondii infection and changes in the behavior. Neuromodulators may represent an ideal mechanism by which T. gondii, at least in part of the expression, can influence the behavior of the infected animal or even human host.