In vitro inhibition of blood cholinesterase activities from cattle by triazole fungicides

摘要

The changes in cattle acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities after exposure to tebuconazole-based fungicides (Orius and Prosaro?) in vitro were determined spectrophotometrically according to the Ellman method. The fungicides induced the decrease in AChE and BChE levels in a dose-dependent manner. Statistically significant inhibition of erythrocyte AChE levels was observed in the concentration range from 150 to 300 μg ml~(-1) (p < 0.001) for Orius and from 100 to 300 μg ml~(-1) for Prosaro? (p < 0.01 and p < 0.001, respectively). Levels of BChE activity were more reduced for the fungicide Orius (40-50%) than for Prosaro?. Statistical significance in the inhibition of BChE activity was found after exposure of cattle plasma to both fungicides at concentrations starting from 150 μg ml~(-1) (p < 0.001). Our results indicate that tebuconazole-based fungicides are able to reduce cattle AChE and BChE activities.