全氟辛烷磺酸（PFOS）急性暴露对斑马鱼鳃显微结构的影响

采用光镜和电镜的方法,探讨了高浓度全氟辛烷磺酸(PFOS)急性暴露对斑马鱼(Danio rerio)鳃显微结构的影响.暴露组PFOS浓度分别为0.5、1、2mg·L-1,同时设对照组,连续暴露7d,取鳃制备石蜡切片,进行光镜和扫描电镜观察.结果表明,7d后PFOS暴露组斑马鱼鳃部均有不同程度的损伤,石蜡切片上可观察到暴露组鱼鳃上皮细胞坏死脱落,鳃小片断裂或融合,并伴有鳃丝充血,且病变程度随PFOS浓度的升高而加重;扫描电镜下可观察到暴露组鱼鳃鳃丝表面分泌物增多,鳃丝细胞脱落或水肿,鳃小片前端细胞破损.高浓度PFOS急性暴露可在短期内对斑马鱼鳃组织造成严重损伤,且损伤程度存在剂量依赖效应.

Acute Effects of Periluorooctane Sulfonate on Microstructure of the Gill of Zebrafish(Danio rerio)

Acute effects of perfluorooctane sulfonate(PFOS)on microstructure of the gill of zebrafish(Danio rerio) were estimated by optical and scanning electron microscopy. Results showed that gills from zebrafish exposed in PFOS at the concentrations of 0.5, 1 and 2mg·L-1 for 7 days had obvious structural alteration. The histopathological changes involved putrescence and desquamation of epithelia cells, rupture and amalgamation of gill lamellae and engorgement of gill filaments, which got severer with the increase of PFOS concentrations. The observed morphological changes involved increased secretion on surface of gill filaments, desquamation and hypertrophy of epithelia cells, evident damage of filaments tips. The results illuminated that PFOS could cause severe damage to the gill of zebrafish after the short period exposure, and the degree of damage had the dose-dependent effect.