Preventive effect of zinc for toxic actions of germanium and selenium on bone metabolism in weanling rats

Abstract

The preventive effect of zinc for the toxic actions of germanium and selenium on bone metabolism was investigated in the femoral diaphysis of weanling rats. Germanium tetrachloride (1.53-30.60 mumol Ge/100 g b.w.) and selenium tetrachloride (1.53-7.65 mumol Se/100 g) was administered orally for 3 days. The doses of 1.53 and 7.65 mumol Ge/100 g caused a significant increase in DNA content although alkaline phosphatase activity was not altered significantly. By the dose of 30.60 mumol Ge/100 g, both alkaline phosphatase activity and DNA content were decreased significantly. Administration of selenium (1.53 and 7.65 mumol/100 g) produced significantly decreases in alkaline phosphatase activity and DNA content. The decreases of the enzyme activity and DNA content caused by administration of germanium (30.60 mumol/100 g) and selenium (7.65 mumol/100 g) were prevented completely by simultaneous injection of zinc sulfate (7.65 mumol Zn/100 g) for 3 days. Administration of zinc also produced appreciable increase in alkaline phosphatase activity and DNA content. The present study indicates that germanium and selenium disturbs bone metabolism in weanling rats, and that this disturbance is reversed by zinc.