脱矿骨的制备及其骨诱导活性的实验研究

目的研究运用超声与盐酸结合的方法制备脱矿骨的脱矿效果及骨诱导活性。方法采用超声条件下酒精脱脂、盐酸脱矿、冻干辐照的方法,制备人类脱矿皮质骨,检测其pH值、钙含量,并比较超声波对脱矿速度的影响。腹腔注射地塞米松造成大鼠的免疫抑制,将所制备脱矿骨异位植入大鼠的股部肌袋,术后不同时间取材,行组织学观察及碱性磷酸酶活性测定以观察脱矿骨的骨诱导活性。结果超声波条件下脱矿速度明显加快;脱矿骨异位植入后4周开始形成软骨细胞与软骨基质,5、6周形成较多的软骨组织,表现出良好的骨诱导活性。结论本研究所制备的脱矿骨具有良好的骨诱导成骨活性,是良好的骨移植材料。

Preparation and osteoinductive activity of human demineralized bone

Objective To study the demineralization of human cortical bone using ultrasound and hydrochloric acid, and to test the osteoinductive activity of the demineralized bone. Methods Demineralized bone was prepared from long bone of human by a series of procedures including defatting with alcohol, demineralization with 0.6N hydrochloric acid in an ultrasound condition, freeze drying and irradiation at a does of 20kGy. The pH and the content of calcium of the demineralized bone were detected. The rate of demineralization was calculated and the effect of ultrasound on the rate of bone demineralization was investigated. Dexamethasone was intraperitoneally injected into Wistar rats in order to suppress their imunno-response. Intramuscular bone transplants were performed by placing the demineralized human bone sheets between bluntly dissected muscle groups of hind limbs of the rats. Histological observation was performed and ALP activity was detected postoperatively to determine the osteoinductive activity of the demineralized bone implants. Results The rate of demineralization was obviously improved by ultrasound. Chondrocytes could be seen within the demineralized bone implants at 4 weeks postoperatively and more cartilages were formed at 5 and 6 weeks, showing that the demineralized bone implants possess good osteoinductive activity. Conclusion Demineralized bone produced according to the methods shows good osteoinductive activity and is a suitable material for bone transplantation.