Behaviour of Mercury in Animals

Abstract

The effects of the simultaneous administration of selenium and mercurials on mercury distribution, and the binding properties of mercurials with the components in the soluble fraction of tissues in 140 male Wister rats were studied.The concentrations of mercury, in both liver and kidney, 120 hours after the simultaneous administration of methylmercuric chloride and sodium selenite were significantly higher than those for groups administered only with methylmercuric chloride. Furthermore, the amount of mercury in the kidney was higher than that in the liver.The concentrations of selenium in the livers and kidneys of the group administered with sodium selenite alone, decreased rapidly in comparison with the group administered with sodium selenite and mercury compounds simultaneously.The soluble portion were fractionated by the gel filtration method on Sephadex G-75. Mercury, both in the liver and kidney of rats administered only with mercuric chloride, was found in the low molecular weight fraction 17-18 and the high molecular weight fraction 32-33, although the fraction 32-33 might correspond to metallothionein. In addition, the amount of mercury bound to the low molecular weight fraction in the kidney showed a tendency to increase gradually with time. On the other hand, the gel filtration patterns of the liver and kidney for the groups administered with methylmercuric chloride and sodium selenite was obviously different from that for mercuric chloride. The groups administered with methylmercuric chloride and sodium selenite were mainly bound to the low molecular weight fraction 17-18 and the high molecular weight fraction 55, although the group administered with mercuric chloride was confined within the high molecular weight fraction 32-33.No obvious discrepancy was seen in the amount of methylmercury between the group administered simultaneously with methylmercury and sodium selenite and that administered with methylmercuric chloride alone.The results indicate that the administration of selenium is identified as the compound responsible for the selective binding and accumulation of mercury in the kidney and liver of rats.