| Chemicals introduced into the environment by anthropogenic activities have the capacity to interfere with the endocrine system of living organisms and act as endocrine disruptors. To date, most studies have focused on estrogenic endocrine disruptors but reports of androgenic endocrine disruptors continue to increase. In the current study, the western mosquitofish, Gambusia affinis was utilized as a model organism to assess the effects of some known and suspected androgenic and estrogenic endocrine disruptors on various reproductive biomarkers. The biomarkers utilized were: anal fin elongation and differentiation, expression of the vitellogenin gene, and sperm production in males. In the studies described in this dissertation, mosquitofish were exposed via the static renewal method to four known or suspected endocrine disruptors: progesterone, methyltestosterone, spironolactone and triclosan. In each case, dose-dependent effects on the biomarkers were observed, indicating that these chemicals have the potential to act as endocrine disruptors. We conclude that reproductive biomarkers in the western mosquitofish, Gambusia affinis used in these studies are suitable for future endocrine disruption studies. |
