The influence of chelating agents on the distribution and biotransformation of methylmercuric chloride in rats.

Male albino rats were injected i.p. with [203Hg]methylmercuric chloride (MMC) and later at different time intervals they received N-acetylpenicillamine, 2,3-dimercaptopropane-1-sulfonate or dimercaptosuccinic acid (DMSA). The animals were sacrificed 24 h after the last chelant treatment and the content of 203Hg was determined in 10 organs. In liver and kidneys, [203Hg]MMC and 203Hg++ were measured separately. DMSA was most effective in removing the mercurial from all organs, except the kidneys, where 2,3-dimercaptopropane-1-sulfonate was better. N-acetylpenicillamine showed only marginal effectiveness. Separate determinations of [203Hg]MMC and 203Hg++ in liver and kidneys showed that DMSA removed more of the organic and 2,3-dimercaptopropane-1-sulfonate more of the inorganic Hg. DMSA injected i.p. or given p.o. removed almost equal amounts of MMC, indicating virtually 100% absorption of the chelating agent from the gastrointestinal tract.