Effects of sulfhydryl compounds on the accumulation, removal and cytotoxicity of inorganic mercury by primary cultures of rat renal cortical epithelial cells.

The effects of sulfhydryl compounds on the accumulation, removal and cytotoxicity of inorganic mercury (Hg) were investigated in primary cultures of rat renal cortical epithelial cells. The compounds investigated were 2,3-dimercaptosuccinic acid, 2,3-dimercapto-1-propanol, D-penicillamine, glutathione (GSH) and L-cysteine. In the accumulation experiment, the cells were co-incubated with Hg and the above compounds for 30 min. (short-term) or 18 hr (long-term). In the removal experiment, cells incubated with Hg were further incubated with the above compounds for 30 min. In both experiments, the alleviative effect of the compounds on the cytotoxicity was estimated by the uptake of neutral red or by cell growth. 2,3-Dimercaptosuccinic acid had the highest antidotal effects except for Hg removal. 2,3-Dimercapto-1-propanol exerted the least antidotal effects in the short-term, as well as in the long-term experiments, 2,3-dimercapto-1-propanol increased the Hg accumulation and the cytotoxicity despite its removal of most of the Hg. Although D-penicillamine, L-cysteine and GSH did not increase the Hg removal in the long-term experiment other antidotal effects were seen.