The Experiment Study On The Pathogenesis Of Postmenopausal Osteoporosis And The Prevention And Treatment Of Osteoporosis With Tamoxifen

Postmenopausal osteoporosis(PMO) and the fracture as a result of PMO are the one of the most serious bone diseases for elder women. Estrogen hormone deficiency has long been known to result in abnormal of bone metabolism in postmenopausal women. It has been made clear in investigations that local skeletal growth factors play an important role in this process. But the mechanisms that lead to the development of it remain unclear at present. Since estrogen replacement therapy as a main method in prevention and cure PMO for a long-term, its ill effects have been funded. For this reason, using the selective estrogen receptor modulator to prevention PMO has been considered. In this study, the following researches have been carried through: (1) to establish an animal model of PMO by ovariectomized(OVX) rats; (2) the expression of Insulin-like Growth Factor-1 in the cancellous bone of lumbar spine was evaluated by immunocytocheinistry; (3) OVX rats were treated with tamoxifen. Bone mineral density measuring, biomechanical properties and bone histomorphometric parameters evaluated the influences of tamoxifen on cancellated bone and cortical bone of ovariectomized rats. The results revealed that: (1) The PMO model was completely established at 16 weeks-3-post-OVX; (2) The expressions of IGF-1 protein in cellson bone trabcula surface of experiment animals were markedly higher than that of control rats. (3) Tamoxifen can inhibit bone toss and the decrease oftriomechanical properties in ovariectomizedSDrats. The results suggested that local skeletal insulin-like growth factors play an important role in bone metabolism process in OVX rats. Tamoxifen can inhibit the decrease of biomechanical properties and increase bone mass in ovariectomized rats.