Inhibition and recovery of brain and tail cholinesterases of Odontophrynus americanus tadpoles (Amphibia: Cycloramphidae) exposed to fenitrothion

LAJMANOVICH R. C.; A. M. ATTADEMO; P. M. PELTZER; JUNGES C. M

Journal of Environmental Biology

TRIVENI ENTERPRISES

Año: 2009 p. 923 - 926

0254-8704

Abstract: We determined the levels of brain acetylcholinesterase (AChE) and tail butyrylcholinesterase (BChE) activities in tadpoles of Odontophrynus americanus exposed to a commercial formulation of fenitrothion. The mean brain AChE activities in the controls tadpoles varied from 6.91 to 6.39 &mol min-1 mg-1 protein, whereas tail BChE activities ranged among 0.26 to 0.17 &mol min-1 mg-1 protein; the two sublethal concentrations of fenitrothion assayed produced AChE and BChE inhibition (p < 0.01). Brain AChE recovered a substantial level of activity with a maximum of 93.2%; after the transference of tadpoles to a free-pesticide solution, whereas tail BChE recovery showed a smaller increase (39%) in the activity at 168 hr after to transference to clear water. According with our results, we suggest that tadpole’s tail BChE presents higher sensibility than brain AChE. concentrations of fenitrothion assayed produced AChE and BChE inhibition (p < 0.01). Brain AChE recovered a substantial level of activity with a maximum of 93.2%; after the transference of tadpoles to a free-pesticide solution, whereas tail BChE recovery showed a smaller increase (39%) in the activity at 168 hr after to transference to clear water. According with our results, we suggest that tadpole’s tail BChE presents higher sensibility than brain AChE. Odontophrynus americanus exposed to a commercial formulation of fenitrothion. The mean brain AChE activities in the controls tadpoles varied from 6.91 to 6.39 &mol min-1 mg-1 protein, whereas tail BChE activities ranged among 0.26 to 0.17 &mol min-1 mg-1 protein; the two sublethal concentrations of fenitrothion assayed produced AChE and BChE inhibition (p < 0.01). Brain AChE recovered a substantial level of activity with a maximum of 93.2%; after the transference of tadpoles to a free-pesticide solution, whereas tail BChE recovery showed a smaller increase (39%) in the activity at 168 hr after to transference to clear water. According with our results, we suggest that tadpole’s tail BChE presents higher sensibility than brain AChE. concentrations of fenitrothion assayed produced AChE and BChE inhibition (p < 0.01). Brain AChE recovered a substantial level of activity with a maximum of 93.2%; after the transference of tadpoles to a free-pesticide solution, whereas tail BChE recovery showed a smaller increase (39%) in the activity at 168 hr after to transference to clear water. According with our results, we suggest that tadpole’s tail BChE presents higher sensibility than brain AChE.