Vinclozolin affects the interrenal system of the rare minnow (Gobiocypris rarus)

Vinclozolin, a widely used fungicide, has been characterized as a potent androgen antagonist. In this study, the effects of vinclozolin on the interrenal system of the rare minnow (Gobiocypris rarus) were evaluated. The results revealed a decline of the renal somatic index (RSI) and the presence of histopathological effects, including shrinkage of the glomerulus and expansion of the Bowman's space in the kidneys, in rare minnows exposed to vinclozolin. Elevated plasma cortisol concentrations in females exposed to ≥ 2 μg/L vinclozolin and males exposed to ≥ 10 μg/L vinclozolin (p<0.05) suggested that endocrine stress was evoked by vinclozolin exposure. Significant decreases in mRNA levels of interrenal crf, pomc, gr, and nka in females and gr and nka in males were observed after exposure to ≥ 0.5 μg/L and 2 μg/L vinclozolin (p<0.05), respectively; however, no changes in expression of these genes were observed in the brain of males (p ≥ 0.159) or females (p ≥ 0.053) compared with the control. The results indicated that female rare minnows were more sensitive than males to vinclozolin exposure. In conclusion, vinclozolin exposure evoked endocrine stress on the hypothalamic-pituitary-interrenal axis in the rare minnow, and the interrenal tissue was more sensitive than the brain tissue to stress caused by vinclozolin exposure. These results provide additional data about the modes of toxicological action of vinclozolin.