三氯生对不同阶段斑马鱼甲状腺内分泌干扰的研究OA

In order to explore the effects of triclosan(TCS)on the endocrine disruption of Danio rerio thyroid,zebrafish fertilized eggs were exposed to different concentrations of TCS solution(0,10,50,250 μg/L).The expression levels of hypothalamus-pituitary-thyroid(HPT)axis-related genes in larvae and juveniles were measured at 4 days and 50 days,respectively.The expression of HPT axis-related genes and the levels of thy-roid-related hormones in the brain and plasma of male zebrafish were measured at 120 days.Compared with the control group,in the 250 μg/L TCS-treated larval group,the expression of thyroid hormone receptor α(Thrα),sodium iodide symporter(Nis),and iodothyronine deiodinase 2(Dio2)genes was significantly in-creased.In juveniles,the expression of thyrotropin-releasing hormone Thrα genes was significantly elevated.Moreover,both juveniles and male adults showed significantly increased expression of Trh.In the male ze-brafish,Thrα,thyrotropin-releasing hormone receptor b(Trhrb),and thyrotropin β(Tshβ)genes was signifi-cantly increased across all TCS treatment groups,while the expression of Thrβ and Dio2 genes was significantly increased in the 50 and 250 μg/L TCS concentration groups.Furthermore,TCS exposure at different doses led to a highly significant increase in plasma levels of thyrotropin-releasing hormone(TRH),triiodothyronine(T3),and thyroxine(T4)levels in male zebrafish.The results indicated that high doses of TCS increased the expression of HPT axis-related genes in zebrafish larvae and juveniles.Lifelong exposure to TCS at environ-mentally relevant doses upregulated the expression of HPT axis-related genes and thyroid hormone receptor genes in the brain of male zebrafish,and increased the levels of thyroid hormones and thyrotropin-releasing hormone in the blood plasma.