STUDY ON THE DISTRIBUTION OF RH STRAIN TOXOPLASMA GONDII IN EXPERIMENTAL INFECTED MICE / 中国人兽共患病学报

ABSTRACT

Aim In order to observe the pathological features and the dynamic distribution of RH strain T. gondii in main organs of infected mice, using indirect immunoenzymatic technique. To provide pathological diagonsising reference of toxoplasmosis and increase to understand the pathologensis of Toxoplasmosis. Methods Mice were infected intraperitoneally with 103 tachyzoites of T. gondii RH strain,and the parasites were detected using indirect immunoenzymatic technique in the liver, spleen, lungs and brain at 2,4,6 and 8 days postinfection. Results The liver was the first organ parasitized at D2, followed by spleen and lungs at D4, the brain at D8. At the early phase of infection, parasites were found on the edge of the liver and spleen. A few parasites were detected within the liver, spleen and lungs with time being. But parasites increased progressively and distributed well during the whole phase. The brain was the last organ to be parasitized. Parasites multiplicated rapidly so that the mice were seriously ill and died. Conclusions The indirect immunoenzymatic technique can demonstrate tachyzoites and Toaxoplasma antigen clearly in infected mice during acute stage. Many organs were infected such as liver, spleen,lungs and brain. The results suggest that the organs in the peritoneal cavity were infected directly by tachyzoites as IP infection, then the parasites disseminate through a blood way, and in the end, tachyzoites cross the blood-brain barries to reach the brain.