Protective Effect of Molybdenum on the Acute Toxicity of Mercuric Chloride. II.

抄録

The protective mechanism of Na₂MoO₄ against the acute toxicity of HgCl₂ was studied by investigating the subcellular distributions of mercury and molybdenum in the liver and kidney of rats treated with either Na₂MoO₄ or HgCl₂ or both, and by performing Sephadex G-75 gel chromatography of the liver and kidney cytosol obtained from these groups. The rats given HgCl₂ (0.03mmol/kg, once, s.c.) after pretreatment with Na₂MoO₄ (1.24mmol/kg, once a day for 3d, i.p.) has decreased the mercury contents in the liver mitochondrial and microsomal fractions and in the renal nuclear fraction, in comparison with those of the rats given HgCl₂ alone. However, the mercury content in the renal cytosol of this group was increased in comparison with that of the rats given HgCl₂ alone. A gel filtration study showed that the increase in mercury content of the renal cytosol of the rats pretreated with Na₂MoO₄ was associated with an increase in the metal content in the metallothionein-like fraction. These results suggest that molybdenum alleviated the acute HgCl₂ toxicity not only by reducing the mercury contents in the mitochondrial and microsomal fractions of liver and in the nuclear fraction of kidney, but also by enhancing the retention of mercury in the renal metallothionein-like fraction.