Effects of water pollution on the proliferative activity in the developing frog brain

In the present research encephalons were considered from an early larval stage of the frog (Sana klepton esculentd). The animals were divided into two groups, i.e., control (CL) and contaminated (CT) frogs, on the basis of chemical analyses. Proliferating activity was evaluated in brain sections after immunoreaction with an anti-PCNA (Proliferating Cell Nuclear Antigen) antibody. The results showed the presence of many immunolabelled cell nuclei in the ventricular walls of the encephalic vesicles, but the patterns appeared changed in the CTs. Moreover, CT tadpoles had Trematoda larvae inside the brain ventricles. The findings showed that amphibian developing nervous tissue is vulnerable to environmental cytotoxic agents and confirmed that amphibians are excellent biomonitoring indicators of water.