Combined effects of methylmercury and ethanol on renal metallothionein and mercury residues in rats fed restricted amounts of a liquid diet.

Simultaneous treatment of rats with ethanol (EtOH) and methylmercury (MeHg) increases the frequency of lesions in the rat kidney. Therefore, it was of interest to us to study the effects of simultaneous treatment of rats with MeHg and EtOH on kidney metallothionein (MT) and mercury residues levels in kidneys of rats maintained on 70% of ad libitum diet. Treatment with MeHg alone induced kidney MT the most (twice) compared to its pair-fed control. Simultaneous treatment with MeHg and EtOH also induced kidney MT but to a lesser degree than treatment with MeHg alone (by about 30%). Ethanol by itself caused a slight increase in kidney MT although starvation resulting from pair-feeding with mercury-treated animals may have contributed to this observation. Simultaneous treatment with MeHg and 2 g/kg EtOH caused a significant reduction in inorganic mercury levels in the kidney (P less than 0.05) compared to treatment with MeHg alone or in combination with 1 g/kg EtOH. Corresponding with the decrease in kidney inorganic mercury levels was a significant increase in urine inorganic mercury levels in this group compared to treatment with 1 g/kg ethanol + MeHg.