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

Postmenopausal osteoporosis(PMO) is a prevalent metabolic bone disease, which threatened the health of elder women seriously. It can increase the probability of fracture. Fracture of any part of the body can be very serious in old people. The pathogenesis of PMO remains unclear in present. How to prevent and cure PMO is an exigent question for discussion. In this study , wo established an animal model of PMO by ovariectomized(QVX) rats. Specimens were collected at 16 weeks post OVX. The following researches were carried through: (1) lumbar vertebrae were processed to determine the mRNA expression of IGF- 1 by a nonradioactive in situ hybridization technique. We examinated the distribution and gray values of positive cells of the cancellous bone by computer image analysis;(2) Examining the serum concentration of Ca-s P alkaline phosphatase(ALP) - insulin-like growth factor-i (IGF-1) .(3) BMP was injected to femoral neck of QVX rats. The effects of BMP were evaluated by fluorescence bservatiorn bone mineral density measuring and bone histomomhometric analysiss.(4) QVX rats were treated with tamoxifen The influence of tamoxifen on cancellated bone and compact bone of ovariectomized rats was evaluated by bone mineral density measuring and bone histomorphometric analysiss. The resits revealed that: 1. The PMO model was established at 16 weeks post-OVX. 2. The expressions of IGF-1 Mrna in cancellous bone of OVX rats were markedly higher than that of control rats. 3. serum concentration of IGF-1 in QVX rats is higher than that in control rats. 4. local injection of BMP can inhibit bone loss,increase bone mass and accelerate bone formation. It also can increase the thickness of femoral neck's cortex. 5. Tamoxifen can increase bone mass of cancellated bone and compact bone of ovariectomized rats, improve microarchitecture of cancellated bone. The results suggested that IGF- 1 play an important role in pathogenesis of PMO;Local application of BMP on femoral neck can prevent and cure fracture of femoral neck;Tamoxifen can increase bone mass of OVX rats, and can avoid side-effects of estrogen.