Prenatal Exposure to Pesticides Disrupts Gonadal Histoarchitecture and Alters Testosterone Levels in Male Caiman latirostris

LUQUE EH, REY F, GONZÁLEZ M, ZAYAS M, STOKER C, DURANDO M, MUÑOZ-DE-TORO M

Mérida, Yucatán México

Simposio; International Forum EcoHealth 2008; 2008

Background. 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) on Caiman latirostris gonadal histo-functional features. Materials 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