雌孕激素合用对去卵巢大鼠骨质疏松的预防作用

目的　观察炔诺酮和炔雌醇联合应用对去卵巢大鼠骨质疏松的预防作用。方法　 4个半月龄大鼠双侧卵巢去除术后预防用药 90d。用骨组织形态计量学方法 ,测定大鼠胫骨近端松质骨静态参数和动态参数 ,观察骨和尿中有机质和无机质的含量 ,血清生化指标和器官指数。结果　炔诺酮6 0 μg·kg-1·d-1和炔雌醇 3 5 μg·kg-1·d-1联合应用可抑制去卵巢大鼠的破骨细胞活性 ,完全对抗其骨转化率增高和骨量丢失的骨质疏松症状 ,同时可使去卵巢大鼠的骨有机质含量增加和尿羟脯氨酸排出量减少。结论　炔诺酮和炔雌醇联合应用可预防去卵巢大鼠骨质疏松

Combination of norethisterone with ethinylestradiol showed synergetic effect on ovariectomy induced osteopeniain rats

AIM To determine whether norethisterone in combination with ethinylestradiol can completely prevent bone loss in ovariectomized rats. METHODS Twenty-four Sprague-Dawley female rats at the age of 4.5 months were sham-operated and treated orally with vehicle, or ovariectomized (OVX) and treated orally with either vehicle or combined norethisterone (norethisterone at 60 μg·kg -1·d -1 and ethinylestradiol at 3.5 μg·kg -1·d -1) for 90 days. Double in vivo fluorochrome labeling was administrated. The undecalcified longitudinal proximal tibial metaphyseal sections were used for the bone histomorphometric analysis. The humerus and urine calcium contents were assayed by the method of atomic absorption spectrometry. The humerus and urine hydroxyproline contents were assayed by colorimetry. Blood serum alkaline phosphatase (ALP) were tested by BECKMAN auto bio-chemistry analyzer. RESULTS After 90 days post OVX the cancellous bone mass and showed high bone turnover indices. Bone hydroxyproline contents were lost markedly. The ALP activity increased. The urine hydroxyproline contents increased significantly. The combined norethisterone treated group prevented bone lost when compared with OVX. The combined norethisterone were shown to inhibit osteoclasts surface and decrese bone turnover rate. The combined norethisterone can increase hydroxyproline contents and reduce urine hydroxyproline contents significantly from OVX group. CONCLUSION Combining norethisterone can prevent OVX-induced cancellous bone loss in rats.