Tissue specific induction of metallothionein synthesis by tumor necrosis factor-alpha

Effect of tumor necrosis factor-alpha (TNF), which is supposed to be one of the mediators responsible for endotoxin, on metallothionein (MT) synthesis was determined in various tissues of rats. At 18 hr after the injection of TNF, MT-I concentrations significantly increased in the liver, lung and heart, but not in the kidney and thymus. In the spleen of TNF-treated rats, MT-I concentrations decreased. Thus, synthesis of MT-I was tissue specific and dose-dependent. In the liver, the synthesis of both metallothionein-I and metallothionein-II was observed and the rate of the induction was greater in the latter. Antioxidative role of the MT synthesized by TNF was discussed.