PROBIEN   20416
INSTITUTO DE INVESTIGACION Y DESARROLLO EN INGENIERIA DE PROCESOS, BIOTECNOLOGIA Y ENERGIAS ALTERNATIVAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Antioxidant metabolism and development in Bufo arenarum embryos exposed to azynphos methyl
Autor/es:
LASCANO C; FERRARI A; VENTURINO A
Lugar:
Mar del PLata
Reunión:
Congreso; 43ª Reunión Anual de la SAIB; 2007
Institución organizadora:
SAIB
Resumen:
Amphibians are very susceptible to environmental contaminants,
being the toad B. arenarum particularly threatened during its
embryonic development by the massive application of the
organophosphate azynphos methyl (AM) used for pest control in
Norpatagonia valleys. Our objective is to determine if reactive
oxygen species (ROS) in connection with altered polyamine (PA)
metabolism contribute to altered embryonic development.
Embryos were continuously exposed until complete development
to 0.5, 2 and 9mg/l AM. Antioxidant enzyme activities were
measured. Catalase was early increased by 0.5mg/lAM returning
to control levels thereafter.GSHreductase was also early increased
by all doses of AM, while GSH peroxidase tended to decrease at
late stages. GST was not affected by AM. Putrescine levels
increased throughout development, rising significantly in exposed
embryos, while spermidine and spermine were decreased in late
embryos exposed to 9mg/l AM. These effects are accompanied
with a dose dependent increase in the number of embryonic
malformations. The results suggest that catalase and GSH
reductase are early induced in response to mild exposure to AM,
while in later embryonic stages the antioxidant enzymes are altered
by the increase of oxidative stress. PA levels suggest an oxidative
metabolization to putrescine, contributing to oxidative stress and
altered development.