Vitellogenin expression, ovarian growth and hormone levels are affected by atrazine in the crayfish Procambarus clarkii

SILVEYRA, GABRIELA R.; SILVEYRA, PATRICIA; VATNICK, I.; MEDESANI, D.A.; RODRIGUEZ, ENRIQUE M

Roma

Congreso; SETAC Europe 28th Annual Meeting; 2018

SETAC

Atrazine, a widely used herbicide, has been categorized as asuspected endocrine disruptor for many years. Although several studies haveinvestigated the effects of atrazine exposure on reproductive function, itssafety remains controversial and the mechanisms of its toxicity remain unclear.In this study, we tested the hypothesis that atrazine can affect reproductionin crayfish through dysregulation of vitellogenin expression and hormonesynthesis. Adult female crayfish (Procambarusclarkii) were exposed during one month to atrazine at concentrations of 1or 5 mg/L. At the end of the exposure, ovaries, hepatopancreas and hemolymph sampleswere harvested for analysis of vitellogenin expression and steroid hormonelevels. Ovarian tissue was also sampled for both biochemical and histologicalanalyses. Atrazine-exposed crayfish had a lower expression of vitellogenin in theovary and hepatopancreas, as well as smaller oocytes and reducedvitellogenin content in the ovary. Despite these effects, circulating levels ofestradiol increased in females exposed to 5 mg/l of atrazine, showing that theinhibiting effect of atrazine on vitellogenin production was not related to alower secretion of sexual steroids; instead, some early stimulating effects ofestradiol on vitellogenesis could have occurred, particularly in thehepatopancreas. Together, our data showed that atrazine exposure was able toinhibit vitellogenin production in the crayfish P. clarkii, altering on the other hand the normal balance of sexsteroids.