The present study aims to investigate the effects of pre-pubertal exposure of male and female mice to a commercial formulation of glyphosate on sexual dimorphism observed in animal models of emotionality, anxiety and depression. For this, mice were exposed from 23 days of age (PND) until PND 45 to glyphosate (50 mg/kg, per os) or saline solution, and, ten days after the end of treatments, male and female mice were observed in the open field (OF), elevated plus maze (EPM) or forced swimming test (FWT). Results showed that exposure to glyphosate: 1) reduced the locomotion frequency of male mice similarly to female mice in the OF and female mice had an increase in rearing behavior and in the immobility time; 2) reduced in male mice the motor activity both in the OF and EPM, while no effects were observed in female mice; 3) in the SWT male mice had a decreased time of float similarly female mice. We concluded that pre-pubertal exposure to glyphosate reduced in male mice the capacity of exploration in the OF and EPM tests suggesting that the herbicide interfered with the central mechanism related to brain masculinization of exploratory and anxiety behavioral models. In the FWT it was observed a decreased depressive response in male mice while in female an increased response was detected.

O presente estudo teve como objetivo investigar em camundongos machos e fêmeas o efeito da exposição a uma formulação comercial de glifosato durante o período de pré-pubere em modelos comportamentais de emocionalidade, ansiedade e depressão. Para isto, camundongos foram expostos a partir de 23 dias de idade (dia pós-natal- PND) até o PND 45 ao glifosato (50 mg/kg, oral route) ou solução salina. Dez dias após o término do tratamento, os animais, machos e fêmeas, foram observados no campo aberto (OF), labirinto em cruz elevado (EPM) ou teste de natação forçada (FWT). Os resultados mostraram que a exposição ao glifosato: 1) reduziu de forma similar a frequência de locomoção dos camundongos em ambos os sexos; 2) reduziu a atividade motora tanto no OF como no PM em camundongos machos, sem alterações observadas em fêmeas; 3) no SWT os camundongos machos apresentaram redução no tempo de flutuação similar ao das fêmeas. Concluiu-se que a exposição pré-pubere ao glifosato reduziu em machos a capacidade de exploração no OF e EPM e no tempo de flutuação no FWT sugerindo que o herbicida interferiu com mecanismos centrais relacionados com masculinização do cérebro ligados a exploração e ansiedade. No FWT observou-se menor depressão em machos e exacerbação da resposta em fêmeas. | The present study aims to investigate the effects of pre-pubertal exposure of male and female mice to a commercial formulation of glyphosate on sexual dimorphism observed in animal models of emotionality, anxiety and depression. For this, mice were exposed from 23 days of age (PND) until PND 45 to glyphosate (50 mg/kg, <em>per os</em>) or saline solution, and, ten days after the end of treatments, male and female mice were observed in the open field (OF), elevated plus maze (EPM) or forced swimming test (FWT). Results showed that exposure to glyphosate: 1) reduced the locomotion frequency of male mice similarly to female mice in the OF and female mice had an increase in rearing behavior and in the immobility time; 2) reduced in male mice the motor activity both in the OF and EPM, while no effects were observed in female mice; 3) in the SWT male mice had a decreased time of float similarly female mice. We concluded that pre-pubertal exposure to glyphosate reduced in male mice the capacity of exploration in the OF and EPM tests suggesting that the herbicide interfered with the central mechanism related to brain masculinization of exploratory and anxiety behavioral models. In the FWT it was observed a decreased depressive response in male mice while in female an increased response was detected.