Selective Modulators of Oestrogen Receptors – Mechanism of Action and Use inTreatment

Overview

Sexual steroid hormones, androgens and oestrogens, are significant factors for the maintenance ofthe quality of bones, and their decline in old age may participate in the development of osteoporosis.The marked variability of the effect of oestrogenic substances in different tissues led to thedevelopment of new substances which should have these oestrogenic properties different fromnatural oestrogens. They should have a positive effect on bone and the cardiovascular systemwithout affecting the organs of reproduction. With regard to comparison of effects of this group ofsubstances at the level of oestrogen receptors in different organs they may be included in the groupof selective modulators of oestrogen receptors (SERM). Representatives of these substances com-prise tamoxifen, commonly used in the treatment of breast tumours, and raloxifen used in thetreatment of postmenopausal osteoporosis. It is assumed that further advances at the level ofmolecular biology of oestrogen receptors will lead to a further extension and classification of SERM.

Key words:
osteoporosis, oestrogen, tamoxifen, raloxifen