Srivastava Ayan, Verma Neeraj, Mistri Arup, Ranjan Brijesh, Nigam Ashwini Kumar, Kumari Usha, Mittal Swati, Mittal Ajay Kumar
Skin Physiology Laboratory, Centre of Advanced Study, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India.
Zoology Section, Mahila Mahavidyalaya, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India.
Environ Sci Pollut Res Int. 2017 Mar;24(9):8671-8681. doi: 10.1007/s11356-017-8517-4. Epub 2017 Feb 15.
Histopathological changes and alterations in the activity of certain metabolic and antioxidant enzymes were analyzed in the head skin of Labeo rohita, exposed to sublethal test concentrations of the azo dye, Eriochrome black T for 4 days, using 24 h renewal bioassay method. Hypertrophied epithelial cells, increased density of mucous goblet cells, and profuse mucous secretion at the surface were considered to protect the skin from toxic impact of the azo dye. Degenerative changes including vacuolization, shrinkage, decrease in dimension, and density of club cells with simultaneous release of their contents in the intercellular spaces were associated to plug them, preventing indiscriminate entry of foreign matter. On exposure of fish to the dye, significant decline in the activity of enzymes-alkaline phosphatase, acid phosphatase, carboxylesterase, succinate dehydrogenase, catalase, and peroxidase-was associated with the binding of dye to the enzymes. Gradual increase in the activity of lactate dehydrogenase was considered to reflect a shift from aerobic to anaerobic metabolism. On transfer of azo dye exposed fish to freshwater, skin gradually recovers and, by 8 days, density and area of mucous goblet cells, club cells, and activity of the enzymes appear similar to that of controls. Alteration in histopathology and enzyme activity could be considered beneficial tool in monitoring environmental toxicity, valuable in the sustenance of fish populations.
采用24小时更新生物测定法，分析了暴露于偶氮染料依来铬黑T亚致死试验浓度4天的露斯塔野鲮头部皮肤的组织病理学变化以及某些代谢酶和抗氧化酶活性的改变。肥大的上皮细胞、黏液杯状细胞密度增加以及表面大量黏液分泌被认为可保护皮肤免受偶氮染料的毒性影响。包括空泡化、萎缩、尺寸减小以及棒状细胞密度降低并同时将其内容物释放到细胞间隙的退行性变化与堵塞这些部位有关，可防止异物随意进入。鱼类暴露于该染料后，碱性磷酸酶、酸性磷酸酶、羧酸酯酶、琥珀酸脱氢酶、过氧化氢酶和过氧化物酶等酶的活性显著下降，这与染料与酶的结合有关。乳酸脱氢酶活性逐渐增加被认为反映了从有氧代谢向无氧代谢的转变。将暴露于偶氮染料的鱼类转移到淡水中后，皮肤逐渐恢复，到第8天时，黏液杯状细胞、棒状细胞的密度和面积以及酶的活性与对照组相似。组织病理学和酶活性的改变可被视为监测环境毒性的有益工具，对鱼类种群的维持具有重要价值。
