Organophosphate flame retardants (OPFRs) have been widely used as alternatives to polybrominated diphenyl ethers for fire prevention. OPFRs are suspected of causing potential thyroid disruption in humans. In fish, their thyroid hormone modulation is reported but the mechanisms of this modulation are less understood. Thyroid-disturbing effects of OPFRs were evaluated using adult zebrafish (Danio rerio) following 14d exposure to tris(1,3-dichloro-2-propyl) phosphate (TDCPP) or triphenyl phosphate (TPP). Plasma concentrations of thyroid hormones were measured and transcriptions of several genes involved in thyroid function were quantified in brain, thyroid, and liver. Exposure to TDCPP or TPP led to significant decreases in plasma triiodothyronine (T3) and thyroxine (T4) concentrations in the male fish, while the increases were observed in the female fish. Exposure to the OPFRs also altered the transcription of regulatory genes and receptors in hypothalamus, pituitary, and thyroid of the fish in sex-dependent manner. In the male fish, transcriptions of corticotropin-releasing hormone (crh) and thyroid-stimulating hormone (tsh) in the brain were significantly up-regulated, probably as a compensation for hypothyroidism, but thyroglobulin (tg) and deiodinase 2 (dio2) were down-regulated in thyroid or liver. In contrast, in the females, transcriptions of crh and tsh genes were significantly down-regulated. These observations show that TDCPP and TPP exposure can lead to sex-dependent disruptions of thyroid hormone balances in the adult zebrafish through alterations of the hypothalamus-pituitary-thyroid (HPT) axis.

有机磷酸酯阻燃剂（OPFRs）已被广泛用作多溴二苯醚的替代品，以用于防火。怀疑OPFR会导致人类潜在的甲状腺破坏。在鱼类中，据报道其甲状腺激素调节作用，但这种调节作用的机理尚不清楚。使用成年斑马鱼（Danio rerio）评估OPFRs的甲状腺干扰作用）暴露于磷酸三（1,3-二氯-2-丙基）（TDCPP）或磷酸三苯酯（TPP）14天后。测量血浆中甲状腺激素的浓度，并定量脑，甲状腺和肝脏中与甲状腺功能有关的几个基因的转录。暴露于TDCPP或TPP导致雄鱼血浆三碘甲状腺素（T3）和甲状腺素（T4）浓度显着降低，而雌鱼则有所升高。暴露于OPFRs还以性别依赖性方式改变了鱼的下丘脑，垂体和甲状腺中的调节基因和受体的转录。在雄鱼中，促肾上腺皮质激素释放激素（crh）和促甲状腺激素（tsh）的转录可能是对甲状腺功能低下的一种补偿，大脑中的蛋白显着上调，但甲状腺或肝脏中的甲状腺球蛋白（tg）和脱碘酶2（dio2）则下调。相反，在雌性中，crh和tsh基因的转录显着下调。这些观察结果表明，通过下丘脑-垂体-甲状腺（HPT）轴的改变，TDCPP和TPP暴露可导致成年斑马鱼甲状腺激素平衡的性别依赖性破坏。