Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao Key Laboratory for Marine Fish Breeding and Biotechnology, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, People's Republic of China.
Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao Key Laboratory for Marine Fish Breeding and Biotechnology, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, People's Republic of China; Aquacultural Engineering R&D Team, Dalian Ocean University, Dalian, People's Republic of China.
Comp Biochem Physiol C Toxicol Pharmacol. 2019 Nov;225:108578. doi: 10.1016/j.cbpc.2019.108578. Epub 2019 Jul 30.
Nitrite (NO) can act as a toxic nitrogenous compound with the potential to disrupt endocrine systems in fish. The aim of the present study was to investigate the effects of nitrite on the thyroid endocrine system of Takifugu rubripes. Fish were exposed to 0, 0.5, 1, 3, and 6 mM nitrite concentrations. Blood was collected to assay the concentrations of thyroid-stimulating hormone (TSH), thyroxine (T), triiodothyronine (T), free thyroxine (FT), free triiodothyronine (FT), and 3,3,5'-triiodothyronine (rT), as well as the activity of iodothyronine deiodinases (Dio1, Dio2, and Dio3,) after 0, 12, 24, 48, and 96 h of exposure to nitrite. The first branchial arch to the third branchial arch of T. rubripes were sampled and fixed, and thyroid morphology was observed. The results showed that exposure to nitrite significantly increased the concentrations of TSH, T, FT, and reduced the concentrations of T, FT, and rT. The activity of Dio1 and Dio2 increased significantly, whereas Dio3 activity decreased significantly. Additionally, thyroid follicles degenerated and became blurred and most colloid material disappeared 96 h after exposure to high nitrite concentrations. Based on these results, high nitrite concentration exposure can disturb thyroid hormone homeostasis, alter thyroid follicle morphology, and result in thyroid endocrine toxicity.
亚硝酸盐（NO）可以作为一种有毒的含氮化合物，有可能破坏鱼类的内分泌系统。本研究的目的是研究亚硝酸盐对红鳍东方鲀甲状腺内分泌系统的影响。将鱼暴露于 0、0.5、1、3 和 6 mM 的亚硝酸盐浓度中。采集血液以测定促甲状腺激素（TSH）、甲状腺素（T）、三碘甲状腺原氨酸（T）、游离甲状腺素（FT）、游离三碘甲状腺原氨酸（FT）和 3,3,5'-三碘甲状腺原氨酸（rT）的浓度，以及碘甲状腺原氨酸脱碘酶（Dio1、Dio2 和 Dio3）的活性，在暴露于亚硝酸盐 0、12、24、48 和 96 h 后。采集红鳍东方鲀的第一鳃弓到第三鳃弓并固定，观察甲状腺形态。结果表明，暴露于亚硝酸盐会显著增加 TSH、T、FT 的浓度，并降低 T、FT 和 rT 的浓度。Dio1 和 Dio2 的活性显著增加，而 Dio3 的活性显著降低。此外，甲状腺滤泡退化，变得模糊，高浓度亚硝酸盐暴露 96 h 后大部分胶体物质消失。基于这些结果，高浓度亚硝酸盐暴露会扰乱甲状腺激素平衡，改变甲状腺滤泡形态，并导致甲状腺内分泌毒性。
