Acute toxoplasmosis can increase serum dopamine level.

Toxoplasmosis is a globally parasitic zoonotic disease transmitted by Toxoplasma gondii protozoa. This infection in its chronic form can cause a change in its host's specific behavior and is also associated with developing neuropsychological symptoms in humans. Changes in neurotransmitters' levels, especially dopamine, have been identified as a behavior change factor in the infected host. This study aimed to evaluate serum dopamine levels in acute murine toxoplasmosis. In this study, 50 mice infected with Toxoplasma were studied in 5 separate groups, and ten healthy mice were considered as negative control. For five consecutive days after parasite injection, blood sampling and serum isolation were performed daily from one of the groups. Serum dopamine levels were measured by HPLC method. Statistical studies showed that serum dopamine on the first to the fourth day after parasite inoculation was the same as the negative control, but the fifth day began to increase. The present study results indicate that dopamine production in mice infected with Toxoplasma gondii increases from day five after infection. This result suggests that in acute toxoplasmosis, dopamine production is low, and the trend of chronic disease increases dopamine production. © Indian Society for Parasitology 2021.