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(T/EH048) Antigenic and ultrastructural detection of changes induced in Rainbow trout liver by dichloroaniline. Lyons Alcantara, Maria1, Lambkin, Helen2, Lyng, Fiona 2, Kilemade, Michael2, Fitzgerald, Richard3, Mothersill, Carmel2, 1 2 3 ABSTRACT- 2,4 Dichloroaniline (2,4-DCA) effects have been studied in mammals but not in aquatic organisms. This highly toxic pollutant is commonly found in wastewater as an endproduct of the agrochemical and pharmaceutical industry, production of dyestuffs, antioxidants and pigments. In the present study, Rainbow trout (Oncorhychus mykiss), weighing an average of 250 - 300 g, were exposed to 2,4-DCA. The concentrations used were 2 and 10 microM 2,4 DCA . Fish were exposed to the pollutant in tanks for 6 and 13 days. Animals were killed in a humane way. Livers were dissected immediately and fixed 10% formalin (4 per cent formaldehyde) for histology and 2.5% glutaraldehyde for electron microscopy. Antibodies against detoxification systems (cytochrome CYP450 and p-glycoprotein), proliferation antigens (PCNA, Ki67 and cyclin) and oncogenes (c-myc, bcl2, p53) were tested on paraffin sections of the liver by immunocytochemistry. An Avidin-Biotin immunoperoxidase method was used to visualise cell antigen expression. The immunocytochemical results indicate increased expression of CYP-450, p-glycoprotein and some oncogenes. A decrease in the level of cellular proliferation was observed. Damage at the ultrastructural level was observed with changes in the nucleus and cytoplasmic organelles. In conclusion, expression of some of the antibodies may serve as a biological monitor for exposure to certain classes of xenobiotic chemicals in the environment. Key words: toxicology, 2,4 dichloroaniline, rainbow trout, immunocytochemistry |
