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

CASCO, VICTOR; IZAGUIRRE, FERNANDA; MARIN, LILIANA; VERGARA, NATALIA; LAJMANOVICH, RAFAEL C.; PELTZER, PAOLA M.; PERALTA-SOLER, ALEJANDRO

CELL BIOLOGY AND TOXICOLOGY

Springer Netherlands Publisher-Kluwer Academic Publisher

Lugar: Dordrecht-Netherlands; Año: 2006 vol. 21 p. 1 - 10

0742-2091

Cypermethrin (CY) (RS)-alpha-cyano-3-phenoxybenzyl (1RS)-cis-, trans-3- (2,2, -dichlorovinyl)-2,2-dimethylcyclopropane carboxylate), a synthetic pyrethroid type II, is among the most active insecticides. Tadpoles of Bufo arenarum toad treated at CY concentration upper 39 µg CY/L shown a massive apoptotic response of the central nervous system immature cells in acute oral toxicity tests. Optic and electronic microscopic studies shown brain intermediate and marginal layer disorder and alterations. Cerebral immature cells presented cellular shrinkage, DNA fragmentation and increase of intercellular spaces. However, we couldn’t detect changes in the cell adhesion molecules expression as N-CAM180, N-cadherin, a- and b-catenin by the immunohistochemical analysis. The dose-dependent effect produce by cypermethrin was corroborate using morphometric analysis and in situ TUNEL. Morphometric analysis shown that the apoptotic cell population significantly increase from 625 mg CY/L. In the present work we corroborate the high toxicity of pyrethroids for Bufo arenarum larval stages. Our results show that lower doses than those are utilized in rutine applications cause a apoptotic response of the central nervous system cells in acute oral toxicity test. This response significantly increase upper 625 mg CY/L. These results agree with our previous studies realized in Physalaemus biligonigerus, un another specie of our region. We postulate that cypermethrin cause neurotoxicity and conduce at apoptotic cell death in tadpoles of Bufo arenarum, and consequently high mortality index.