Effects of the antitubulin drug trifluralin on the proliferation and metacyclogenesis of Trypanosoma cruzi epimastigotes.

Trypanosoma cruzi epimastigotes were exposed to varying micromolar concentrations of the dinitroaniline antitubulin trifluralin. The effects of trifluralin on parasite proliferation, metacyclogenesis, morphology, and uptake of horseradish peroxidase (HRP) were investigated. Parasites exposed to the antitubulin showed some ultrastructural alterations, i.e., formation in some parasites of large, membrane-delimited vacuoles and a significant decrease in the number of HRP-positive reservosomes. Whereas there was no perceptible change in the morphology of either subpellicular or flagellar microtubules, there was a significant inhibition of proliferation and metacyclogenesis at trifluralin concentrations in excess of 100 microM. These concentrations were considerably higher than those reported to produce similar results in Leishmania spp. and T. brucei brucei.