Increase of carboxylesterase activity in Fasciola hepatica recovered from triclabendazole treated sheep.

In the present work, we evaluate in vivo the activity of carboxylesterase of Fasciola hepatica exposed to triclabendazole. We observed a statistically significant increase in enzyme activity at 24 and 48 h post treatment (P<0.01 and P<0.001, respectively). The zymogram of cytosolic fractions identified a protein of 170 kDa containing the carboxylesterase activity. The densitograms of the zymograms confirmed the phenomenon of enzyme induction under the experimental conditions of the assay. These results provide not only the understanding of the importance of this metabolic pathway in flukes but carboxylesterase would also be an enzyme that could participate more actively in the development of anthelmintic resistance at TCBZ.