Mercury distribution studies involving complexes of low-molecular weight thiols and methylmercury.

Abstract

One of the metabolic roles of low molecular weight thiol compounds may be the formation of thiol-methylmercury complexes which can be preferentially translocated across cell membranes. The coadministration of equimolar amounts of the thiol, L-cysteine, with CH/sub 3/Hg increased the short-term accumulation of CH/sub 3/Hg in liver, kidneys and cerebrum, but reduced the level of CH/sub 3/Hg found in plasma. This modification of the distribution pattern of CH/sub 3/Hg by co-administering low molecular weight thiol compounds further suggests that thiol-methylmercury complexes may play a role in the tissue deposition process. In fact, treatment of rats with CH/sub 3/Hg has produced a low molecular weight CH/sub 3/Hg complex in cerebral cytosol. This complex accounted for approximately one-third of the soluble CH/sub 3/Hg and was identified by column chromatography and electrophoresis to be methylmercury-glutathione. The object of this study is to determine if CH/sub 3/Hg and thiol complexes of CH/sub 3/Hg are absorbed and distributed in a manner dependent upon the status of a known ameliorative agent of CH/sub 3/Hg toxicity, selenium.