Droloxifene prevents ovariectomy‐induced bone loss in tibiae and femora of aged female rats: A dual‐energy X‐ray absorptiometric and histomorphometric study

摘要: Our previous studies indicated that droloxifene (DRO), a tissue-specific estrogen antagonist/agonist, prevented bone loss without causing uterine hypertrophy in growing ovariectomized (OVX) rats. Using dual-energy X-ray absorptiometry (DXA) and histomorphometry, the current study compared efficacy of DRO to 17βestradiol (E 2 ) preventing OVX-induced tibiae femora 19-month-old rats determine whether had similar skeletal effects as E aged female Sprague-Dawley were OVX or sham-operated (sham) at 19 months age. The treated with vehicle (oral), while 30 μg/kg/day (sc), 2.5, 5, 10 mg/kg/day (oral) for 8 weeks. Bone mineral density (BMD) whole (WF), distal femoral metaphyses (DFM), shafts (FS), proximal (PF) was determined using DXA. Static dynamic cancellous histomorphometric analyses performed double-labeled undecalcified longitudinal sections from tibial metaphyses. Ovariectomy weeks significantly reduced BMD WF, DFM, FS, PF (from -6 - 15%). Treatment completely decreases WF DFM no significant FS decrease induced by treatment all dose levels. In addition, PF. Furthermore, results showed decreased trabecular volume 34% increased activation frequency 104% it nonsignificantly other indices including percent eroded perimeter, apposition rate, formation rate per controls. levels increases turnover, indicating is an agonist Together findings inhibited body weight gain, total serum cholesterol, effect on weight, we conclude efficacious inhibiting turnover but estrogenic These data suggest may be superior postmenopausal senile osteoporoses. (J Miner Res 1995 ;10 :1256-1262)