Apoptotic cell death in the central nervous system of Bufo arenarum tadpoles induced by cypermethrin

CASCO, V.; IZAGUIRRE, M. F.; MARIN., L.; VERGARA, N; LAJMANOVICH R; PELTZER P.; PERALTA SOLER , A

CELL BIOLOGY AND TOXICOLOGY

Springer

Lugar: Amsterdam; Año: 2006 vol. 22 p. 199 - 211

0742-2091

Tadpoles of the toad Bufo arenarum treated with cypermethrin (CY) at concentrations above 39 ìgCY/L showed dose-dependent apoptotic cell death in immature cells of the central nervous system asdemonstrated by morphometric analysis, the TUNEL method, and DNA fragmentation assay. Light-andelectron-microscopic studies showed structural alterations in the intermediate and marginal layers ofthe brain. Immature cerebral tissue showed cellular shrinkage, nuclear fragmentation and increase ofintercellular spaces. In this study we demonstrated high toxicity of CY to larval stages of Bufo arenarum.Our results show that doses lower than those used in routine insecticide applications can cause massiveapoptosis in the immature cells of the central nervous system. These results coincide with our previousstudies in Physalaemus biligonigerus, confirming the severe toxic effects of CY to the central nervoussystem of anuran species from Argentina. This may increase the mortality index in wild animals andcontribute to the loss of biodiversity in our agroecosystems. We postulate that CY induces apoptosis incentral nervous system cells of Bufo arenarum tadpoles by specific neurotoxic mechanisms.