Histo-morphological and molecular changes on gonadal differentiation in Caiman latirostris males. Effect of exposure in ovo to atrazine

MUÑOZ DE TORO, M; GALOPPO, G; LUQUE, E; CANESINI, G; RAMOS, JG; TAVALIERI, Y

Buenos Aires

Congreso; Reunión conjunta de Sociedades de Biociencias; 2017

Sociedad Argentina de Biología

Atrazine (ATZ), a widely used herbicide is an endocrine disruptorcompound (EDC) that alters male reproductive tissues during development.Caiman latirostris is a species with temperature dependentsex determination (TSD), thus, egg incubation temperature isthe main factor that determines the sex during a thermo-sensitiveperiod (TSP). Caimans have eco-physiological features that makethem particularly vulnerable to EDC exposure. The aim of this studywas to describe the effects of an environmentally relevant dose ofATZ on gonad histo-morphology and the expression patterns of keymolecules involved in embryonic testis development. Caiman eggswere incubated at male producing temperature, at stage 20, priorto TSP, vehicle (TSD-males) or 0.2 ppm of ATZ (ATZ-males), wereadministered. Embryos were obtained in stages 22, 24 and 27. Gonadhisto-morphology was studied using trichromic stained sectionsand the expression of estrogen receptor alfa (ERα), progesteronereceptor (PR), proliferating cell nuclear antigen (PCNA) and TAp63isoform (p53 family member) were assessed by IHC. ATZ-malesshowed morphological changes in the gonad at stage 27. ERα expressionshowed a decline towards the end of development bothin TSD and in ATZ-males (p