Increase of Calcium Concentration in the Testes of Mice Treated with Rare Earth Metals

Abstract

Rare earth metals (REMs) are widely used in several emerging technologies, however, little is known about their biological effects. In this study we examined the effects of REMs, including lanthanum (La), neodymium (Nd), gadolinium (Gd), terbium (Tb) and ytterbium (Yb) on the testes of mice. Mice were treated i.v. with a single dose of 20 or 200μmol REM/kg as chloride. The testicular weights, lipid peroxidation, and alterations such as hemorrhagic inflammation, were examined 5 d after the administration. The concentration of Ca in the testes was also determined by atomic absorption spectrometer. No significant changes in testicular weights, lipid peroxidation, or alterations were observed by the administration of these REMs at either dose. However, the concentration of Ca in the testes was markedly increased at both doses. There was no significant difference in the Ca concentration between dose levels or among the REMs. These results suggest that the REMs induce increased Ca concentration in mice testes, and this might be a significant aspect of their toxic mechanisms.