猪骨蛋白对骨质疏松模型大鼠血清磷水平与骨密度的影响

背景: 有报道显示美国处于高风险的骨质疏松妇女中磷水平较高，这是否意味着降低血磷水平的物质将会为防治骨质疏松提供新的有效手段？目的：观察猪骨蛋白对骨质疏松大鼠骨密度和血清中钙及磷水平的影响。方法：以肌肉注射地塞米松建立Wistar大鼠骨质疏松模型。造模后以数字表法随机分为生理盐水组、接骨七哩片组、50，100， 200 mg/kg猪骨蛋白组，不作任何处置大鼠作为正常对照。治疗12周后，分离血清并用生物化学方法测定血清磷和血钙水平，同时收集大鼠胫骨制作成骨切片，以QDR-4000双能X射线吸收仪测定各组大鼠胫骨吸光度值；苏木精-伊红染色观察胫骨骨髓腔变化。结果与结论：各组之间血清钙浓度比较差异无显著性意义(P > 0.05)。与生理盐水组比较，50，100，200 mg/kg猪骨蛋白组大鼠血清磷浓度下降(P < 0.05)。50，100，200 mg/kg猪骨蛋白组、接骨七哩片组骨密度值高于生理盐水组(P < 0.05)。正常对照组大鼠胫骨的骨髓腔是小的，生理盐水组大鼠胫骨的骨髓腔特别大，50，100，200 mg/kg猪骨蛋白组、接骨七哩片组大鼠胫骨骨髓腔比生理盐水组大鼠胫骨骨髓腔小。结果提示猪骨蛋白不改变骨质疏松大鼠血清钙的水平，但它能降低骨质疏松大鼠血清磷的浓度，增加骨密度。不过，在该实验浓度范围内，没有显示剂量效应关系；猪骨蛋白也能缩小骨质疏松大鼠胫骨骨髓腔。

Effects of porcine bone protein on serum phosphorus level and bone mineral density in a rat model of osteoporosis

BACKGROUND: Several studies have demonstrated that many American women who are at high risk of developing osteoporosis have higher levels of serum phosphorus. This indicates that some substances which can lower the serum level of phosphorus will supply a new and effective method to prevent and treat osteoporosis. OBJECTIVE: To observe the influences of porcine bone protein on bone mineral density (BMD) and serum levels of calcium and phosphorus in a rat model of osteoporosis. METHODS: Wistar rat models of osteoporosis were established by intramuscular injection of dexamethasone. Rat models were randomly divided into physiological saline, Jiegu Qili tablet, 50, 100, 200 mg/kg porcine bone protein groups. Rats that did not receive any treatments served as normal controls. After 12 weeks of treatment, serum was collected and serum levels of phosphorus and calcium were determined by biochemistry method. At the same time, tibia sections were made to determine tibial DMD by QDR-400 dual energy X-ray absorptiometry and to observe tibia marrow cavity by hematoxylin-eosin staining. RESULTS AND CONCLUSION: There was no significant difference in serum level of calcium among groups (P > 0.05). Compared with the physiological saline group, serum level of phosphorus in the 50, 100, 200 mg/kg porcine bone protein groups was significantly decreased (P < 0.05). BMD was significantly higher in the 50, 100, 200 mg/kg porcine bone protein, Jiegu Qili tablet groups than in the physiological saline group (P < 0.05). The tibia marrow cavity was smallest in the normal control group and largest in the physiological saline group. The tibia marrow cavity was larger in the 50, 100, 200 mg/kg porcine bone protein, Jiegu Qili tablet groups than in the physiological saline group. These results indicate that porcine bone protein cannot change the serum level of calcium, but it lowers serum level of phosphorus, and increases BMD, in a rat model of osteoporosis. However, the dose-dependent effect of porcine bone protein was not observed within the present experimental dosage. In addition, porcine bone protein can also reduce the marrow cavity of the tibia of rats with osteoporosis.