INVESTIGADORES
LUQUE Enrique Hugo
congresos y reuniones científicas
Título:
Prenatal Exposure to Pesticides Disrupts Gonadal Histoarchitecture and Alters Testosterone Levels in Male Caiman latirostris
Autor/es:
EH LUQUE; M GONZÁLEZ; M ZAYAS; C STOKER; M DURANDO; M MUÑOZ-DE-TORO
Lugar:
Merida, México
Reunión:
Congreso; International EcoHealth Forum; 2008
Resumen:
The encroachment of natural habitats for their
use as croplands is on the rise in Argentina. Growing agriculture
brings growing use of agrochemicals and increased exposure
of wildlife to pesticides classified as endocrine disrupter
compounds (EDCs). A native species particularly exposed to
EDCs is the broad-snouted caiman (Caiman latirostris).
Objective. The aim of this study was to test the consequences of
in ovum exposure to atrazine (ATZ) and endosulphan (END)ATZ
on Caiman latirostris gonadal histo-functional features.
Material and methods. Caiman eggs were collected from
pristine areas and incubated in controlled conditions at male
producing temperature 33ºC). At stage 20 of embryonic development,
the sensitive stage for gonadal sex determination,
eggs were exposed to END or ATZ. Gonadal histo-morphology
was examined in caiman hatchlings and serum levels of
testosterone were measured.
Results. Independently of treatments, all the eggs incubated
at 33ºC resulted in male hatchlings. Tortuous seminiferous
tubules with increased perimeter, disrupted distribution of
peritubular myoid cells (desmin positive), and emptied tubular
lumens characterized the testes of pesticide exposed
caiman. An imbalance between proliferative activity and
cell death was observed in the testes of caiman exposed to
the higher doses of END, mainly due to a high frequency of
apoptosis in intratubular cells. This altered cell turnover was
associated with decreased testosterone levels.
Conclusions. Prenatal exposure to ecologically relevant doses
of END and ATZ disrupted male gonadal histofunctional
features. Alterations described here could have detrimental
effect on sexual maturation and, ultimately, on the success of
male caiman reproduction.