bBMP异位诱导成骨的组织学长期观察

Long-term histological observation of the ectopic bone induced by the bBMP

目的长期观察并获得单纯牛骨形态发生蛋白（bovine bone morphogenetic protein,bBMP）异位诱导成骨的组织学变化。方法（20±2）g昆明小鼠21只,麻醉后于双侧股部肌肉中直接植入块状bBMP各2mg,分别于第1、2、4、6、8、10、12周各处死3只,切取诱导分化组织,5%戊二醛固定,标本用10%EDTA脱钙后制作5μm石蜡切片,分别行甲苯胺蓝染色,HE染色,丽春红三色染色观察组织学变化情况。结果植入1周,大量分化良好的间充质细胞和幼稚软骨细胞形成一椭圆形分化组织块;植入2周,大量骨小梁生成,部分骨小梁边缘骨化;植入4周,骨小梁转化为成熟的骨质,骨质中有散在于骨细胞中的破骨细胞生成;植入6-12周,椭圆形骨组织块内部小梁骨逐渐吸收、断裂、不连接,但外周骨质逐渐塑形,局部成熟骨质周边仍伴有新生骨形成。结论bBMP无需任何载体即可在肌肉中异位成骨,具有强大的异位骨诱导能力;血供在异位骨的形成和维持中可能起着重要作用。

Objective To observe and get the histological changes of the ectopic bone induced by the bBMP during a long period. Methods Twenty one Kunming rats（20±2）g were used in this experiment,2 mg bBMP was implanted into the rat intramuscular of both sides of the thigh under the anesthesia respectively,differentiated tissues were harvested at 1,2,4,6,8,10 and 12 weeks postoperation.The incised tissues were immersion-fixed in 5%glutaraldehyde,samples were subsequently decalcified in 10%EDTA and processed for paraffin sectioning at 5μm,sections were stained with toluidine blue,hematoxylin and eosin,Masson trichrome. Results One week after the operation,an oval differentiated tissue consisting of a large number of chondroblasts and chondrocytes was formed;two weeks after the operation,a large number of bone trabecular was formed newly and the verge of the trabecular had been mineralized;four weeks after the operation,most of the newly formed bone became more mature,and simultaneously a few osteoclasts were found among the osteoblasts at this period;from 6 weeks to 12 weeks,the inner trabecular in the oval ectopic bone lump was partly absorbed,as a result,the trabecular became rupture and disconnected,but the outer ectopic bone was not found to be absorbed,some newly bone still formed around the mature bone. Conclusions bBMP possesse a strong ectopic osteoinductivity,having the potential for ectopic new bone formation without any carrier.The blood supply may have an important role in producing the new bone and maintaining its existence.