[Effect of tamoxifen on blood calcium and bone structure of normal and ovariectomized rats]

The effect of tamoxifen on calcaemia and framework was studied, both in normal and ovariectomized rats. Tamoxifen caused hypercalcaemia. Only in one of seven animals hypercalcaemia due tamoxifen was accompanied by radiological changes although no structural modification was histologically evident. In ovariectomized rats, tamoxifen dit not produce either hypercalcaemia or radiological changes. These data suggest that the antioestrogenic activity of tamoxifen is involved in the hypercalcaemia it produces.