Chlordimeform, as well as other formamidine pesticides, has been described to induce permanent sex- and regiondependent effects on the development of monoaminergic neurotransmitter systems. The mechanisms that induce these effects are not known, but it has been suggested that these effects could be related to monoamine oxidase (MAO) inhibition. However, chlordimeform is a very weak MAO inhibitor, which suggests that other mechanism should be involved. In this regard, formamidines, in general and chlordimeform, in particular, alter the serum levels of steroid hormones, which regulate the expression of enzymes that mediate the synthesis and metabolism of monoaminergic neurotransmitters. Therefore, an alteration of these hormones in the brain could mediate the effects observed. In order to confirm that the formamidines produce sex hormones disruption in the brain, we evaluated, in the frontal cortex of male and female rats, the effect on the levels of testosterone and estradiol at 11 days of age after maternal exposure to chlordimeform (5 mg/kg body weight). Chlordimeform induced a significant decrease in testosterone and estradiol levels in the prefrontal cortex of rats at 11 days of age. We observed sex interaction with treatment in the content of T and E2. The present findings indicate that after maternal exposure to formamidines, in general and chlordimeform, in particular, a sex hormones disruption in the frontal cortex I induced.
