Atrazine-induced degranulation of thyroid mast cells in peripubertal and adult rats

Abstract

AbstractAtrazine is a commonly used pesticide in the US and the non-EU countries. It is classified as an endocrine-disrupting chemical and is well-known for its reproductive toxicity in mammals and lower vertebrates. The study on atrazine effects on thyroid mast cells was performed on juvenile/peripubertal and adult male Wistar rats orally gavaged with atrazine at doses of 50 mg/kg of body weight (bw) or 200 mg/kg bw. In order to visualize the mast cell population within the thyroid gland, a histochemical staining method of toluidine blue was used. The results of the histological evaluation demonstrated a prominent increase in mast cell degranulation in both age groups and at both atrazine doses. According to the stereological analysis, a statistically significant decrease in the mast cell volume density in the young rats exposed to a higher dose of atrazine was found when compared to the corresponding control. The numerical density of mast cells significantly decreased in a higher-dose atrazine treated adults in comparison to the control. The obtained data suggest that atrazine-affected mast cells would probably have a consequent influence on thyroid follicular cells and/or thyroid microvasculature via paracrine action of released mediators, but might also be involved in already suggested thyroid cancerogenesis.