Osteoblast-like cells from estrogen receptor α knockout mice have deficient responses to mechanical strain

Osteoblast-like cells in primary cultures derived from ERalpha(-/-) mice do not proliferate in response to mechanical strain, unlike those from their ERalpha(+/+) littermates. ERalpha(-/-) cells also lack strain-related NO production and responsiveness to IGFs. Proliferative responsiveness to strain is rescued by transfection with functional ERalpha. ERalpha number or function in bone cells may limit bones' adaptability to mechanical loading.