Oestrogen effects on osteoblasts and osteoclasts.

Although it has been recognized for many years that oestrogen is a key component in the maintenance of normal bone balance, the mechanisms by which oestrogen exerts its influence have remained unresolved. Recent identification of oestrogen receptors in both bone-forming osteoblasts and bone-resorbing osteoclasts has opened up exciting new areas of research on the direct effects of oestrogen on both osteoblasts and osteoclasts. This review presents an updated model for the molecular mechanisms involved in oestrogen action, the mechanism of anti-oestrogen action, and outlines recent advances in knowledge of oestrogen effects on osteoblasts, osteoclasts, and the coupling of bone resorption and bone formation.