Molecular Biological Probes for Assessing Effects of Environmental Xenobiotics atSublethal Levels in Fish Reproduction

摘要

The wide-spread use of polychlorinated biphenyls (PCBs) and/or polynucleararomatic hydrocarbons (PAH) in pesticides and industrial reagents has caused a significant accumulation of these compounds in the aquatic ecosystems. Fish contaminated with these chemicals demonstrate several pathological conditions. Unfortunately, detailed biochemical and molecular studies investigating the sublethal effects of these compounds on fish growth, development and reproduction have not been conducted. Therefore, there is a need to develop rapid, reliable, and sensitive bioassays to assess the toxic effects of PCBs and PAHs present in the aquatic ecosystem at sublethal levels. Studies conducted in the laboratory showed that sublethal levels of PCB and Mirex caused a reduction in the production of an egg yolk protein, vitellogenin, in juvenile rainbow trout induced with 17 -estradiol. It was hypothesized that the induction of vitellogenin could serve as a biocehmical parameter to asses the effects of organic pollutants on fish reproduction. The purpose of the research is to develop a bioassay using the estrogen-responsive vitellogenin gene as a biomarker and rainbow trout and striped bass as experimental animals.