Metallothionein and zinc metabolism in endotoxin shock rats

Zinc metabolism in endotoxicosis was investigated in rats. The zinc concentration in the serum decreased, while zinc contents increased in the lung, kidney and liver. Marked increase in zinc level was observed in the liver. In the liver cells, zinc concentrations of mitochondria and cytosol increased, but not in microsome. Metallothioneins (MTs), which probably participate in zinc metabolism, were induced by endotoxin administration. Although the same level of MT-2 as that of MT-1 was induced by zinc, the level of MT-2 was 3 to 4 fold higher than that of MT-1 by administrations of endotoxin or glucocorticoid hormone. Since no metallothionein was induced directly by addition of endotoxin to the media of cultured cells, the endotoxin was found not to induce MTs directly. The effect of zinc on superoxide generation of polymorphonuclear leukocytes was also studied. Zinc was found to inhibit superoxide generation dose-dependently.