title: Herbicide metolachlor causes changes in reproductive endocrinology of male wistar rats.
abstract: S-metolachlor is a chloroacetanilide herbicide widely used in the agriculture to control weeds and was demonstrated that it increases the activity of the aromatase enzyme in cell cultures, which may culminate as endocrine disruption action in vivo. To investigate this hypothesis, prepubertal Wistar male rats were exposed to metolachlor (5 or 50 mg/kg/day, NOEL for reproductive toxicity: 23.5-26.0 mg/kg/day) from PND23 (postnatal day) to PND53. During this period, the growth of the animals and the age and weight at puberty were recorded. In PND53, tissues were collected and the analysis of LH, FSH, testosterone, dihydrotestosterone (DHT), estradiol serum concentrations, morphometric evaluation of the seminiferous epithelium, and weight of the testes and the seminal vesicle (undrained and drained) was performed (Statistical difference: P < 0.05). Metolachlor caused an increase in serum concentrations of testosterone, estradiol, and FSH and a reduction in DHT but did not alter the LH. There were also observed a higher amount of fluid in the seminal vesicles, precocious puberty, and changes in morphology of the seminiferous epithelium of treated animals. We demonstrated in this paper that prepubertal exposure to S-metolachlor caused changes in reproductive endocrinology of male rats.
authors.affiliation: Department of Pharmacy, State University of Centro-Oeste, R. Simeao Camargo Varela de Sa, 03, 85040-080 Guarapuava, PR, Brazil.
authors.forename: Francielle Tatiane
authors.initials: FT
authors.lastname: Mathias
authors.forename: Renata Marino
authors.initials: RM
authors.lastname: Romano
authors.forename: Hanan Kaled
authors.initials: HK
authors.lastname: Sleiman
authors.forename: Claudio Alvarenga
authors.initials: CA
authors.lastname: de Oliveira
authors.forename: Marco Aurelio
authors.initials: MA
authors.lastname: Romano