Accumulation of Hg(II) Ions in Mouse Adrenal Gland

Female BALBc mice were administered HgCl2 at a single dose of 4 mg/kg i.p. The acute intoxication with Hg(II) salts (2 hr) caused accumulation of Hg(II) ions in the adrenal gland in general, and in the medulla, in particular. Based on data obtained with atomic absorption spectroscopy and quantitative cytochemistry, we determined the amount of mercury (II) in the adrenal glands and found it to be 14.2 ng Hg(II) (3.5 mg/kg wet weight of the adrenals). An uneven distribution of Hg(II) was found within the adrenal gland, not only between the medulla and cortex, but also within the cortex. The applied autometallographic method revealed that the cortex was negative except the zona glomerulosa, whereas the medulla showed a strong reaction localised to the chromaffin granules of the secretory cells. Both adrenaline and noradrenaline producing cells reacted. The comparison of the density of silver grains by scanning densitometry in the medulla and cortex revealed a significantly higher Hg(II) concentration in the medulla compared to the cortex (10 mg/kg vs 2 mg/kg, respectively). The results presented here suggest that there may be a connection between the symptoms of acute Hg(II) intoxication and its adrenal accumulation.