Potencial hepatotóxico do metilmercúrio em camundongos C57BL/6J lactentes

Abstract

Intoxication by methylmercury has been considered a major environmental issue, with reports of exposure cases since the 50’s. The mercury released by anthropogenic activities sediments on soils and waters, where it is converted into its organic methylated form, methylmercury. Being consumed by fishes, it gets to humans through fishing activities, reaching mainly the riverside population. The liver, as a target organ in methylmercury intoxication was the highlight of this study. Given to the wide availability of studies with adult organisms and concerning placental contamination, this one aims to evaluate damages induced exclusively through breastfeeding. For such purpose, postnatal in development wild C57BL/6J mice were used. Animals were divided into two groups: without intoxication and with intoxication, administering 20mg/L methylmercury chloride through drinking water to the last one. Liver samples were collected to perform histological analysis of the liver by optical microscopy. The group that received methylmercury chloride presented normally shaped, sized and colored hepatocytes, as well as absence of mitosis figures or mutagenesis abnormalities, with no necrosis area or increase in the amount of defense cells of Kupffer. No histopathological changes were observed in the intoxicated group, when compared to the control group. Such results indicate that there was no passage of methylmercury via breastfeeding in sufficient amounts to induce histological damage.