Effects of mercurials on renal sulfhydryl and disulfide groups

¹ Department of Physiology, Washington University School of Medicine, Saint Louis, Missouri

Sulfhydryl and disulfide concentrations were determined amperometrically in homogenates and subcellular fractions of kidneys of normal rats and of rats injected with HgCl₂, p-chloromercuribenzoate, or chlormerodrin. In normal kidney —SH greatly predominated. At 3 hr after injection of 3 mg HgCl₂/kg or 7.3 mg chlormerodrin/kg, no significant increase in the concentration of renal —SS— was detected, although the —SS— reductase activity was greatly diminished by the injections. HgCl₂ added in vitro to kidney homogenates in amount corresponding to less than 10% of the total —SH in the preparation also markedly inhibited the utilization of TPNH for reduction of —SS—. In kidneys removed at intervals between 6 and 24 hr after injection of HgCl₂, chlormerodrin, or p-chloromercuribenzoate, increasing concentrations of —SS— with corresponding decreases in —SH concentrations were observed. These increases in —SS— are probably toxic manifestations most evident after diuresis has ceased, although physiologically significant changes in —SS— may occur earlier. Inhibition of —SS— reductase to a lesser extent than that observed with the doses of mercurials used might alter renal function with only small changes in —SS—/—SH, which are eventually overcome.