The protective role of sodium selenite and vitamin E on lung tissue effect of mercuric chloride in rats

Mercury, which is one of the most important environmental and industrial contaminants, adversely affects human health. In this study, male wistar rats whose weight is 300-320 g were used. Rats are separated in two groups as the control group (n=6) and the treated group (n=42). The treated group is seperated into seven groups within their own group. These are group treated with sodium selenite, vitamin E, vitamin E+sodium selenite, mercuric chloride, sodium selenite+mercuric chloride, vitamin E+mercuric chloride and sodium selenite+vitamin E+mercuric chloride. After the administration which lasted 4 week lung tissues of each rat were investigated using light microscope and SOD, CAT, GPx and GST activity and MDA levels were measured in lung tissue. At the end of the 4th week, there is no significant differences were observed between control, sodium selenite, vitamin E and vitamin E+sodium selenite groups.In mercuric chloride treated group while SOD, CAT, GPx and GST activities were significantly lower than the control group, MDA levels were significantly higher compared to the control group.In sodium selenite+mercuric chloride, vitamin E+mercuric chloride and sodium selenite+vitamin E+mercuric chloride treated groups we observed the protective effects on examining parameters but not completely. While some histopathological changes were detected in lung tissue in mercuric chloride treated group, less histopathological changes were observed in sodium selenite+mercuric chloride, vitamin E+mercuric chloride and sodium selenite+vitamin E+mercuric chloride treated groups. As a result, sodium selenite, vitamin E and vitamin E+sodium selenite significantly reduce mercuric chloride induced pulmonary toxicity in rats, but not protect completely.Key Words : Mercuric chloride, Sodium Selenit, vitamin E, lung toxicity, antioxidant enzymes, histopathology