骨不连动物模型的制做及骨不连接区组织BMP的检测

目的:为骨不连的实验研究建立一种客观的动物实验模型,检测骨缺损区骨形态生成蛋白-2(BMP-2)。方法:选取纯种日本大耳白兔,在前臂桡骨中段,截除1.0cm骨段(包括骨膜),骨断端用骨蜡封闭髓腔,分别于4周,6周,8周后经大体标本观察、病理组织学及X线检查确定骨不连形成和骨不连接区组织成分,通过免疫组化检测不同时期骨缺损区组织内骨形态生成蛋白-2(BMP-2)。结果:大体标本肉眼观察、X检查及病理组织学检查均显示骨缺损区无骨性连接,为纤维瘢痕组织填充,断端硬化,髓腔封闭。同时该实验进一步确定了骨缺损区组织BMP-2成份在4周后仍存在于细胞间质内和新生软骨岛的软骨细胞内,含量较新鲜组织明显减少,并且随着时间推移、BMP-2含量会进一步减少。结论:本实验所建立的动物模型,具有骨不连的大体标本、影像、病理学改变,符合骨不连的要求,故可以认为是一种可靠而实用的实验性骨不连动物模型。骨缺损区陈旧性组织内可成骨转化的细胞明显减少,但在新生骨区内仍可见少许细胞,BMP-2仍存在于细胞间质内和新生软骨岛的软骨细胞内,但含量明显下降。因此,外源应用BMP-2,补充骨不连区局部促成骨的成分可有望促进愈合。

Preparation of Expertmental Models of Bone Nonunion and Detection of Endogenic BMP-2 in Area of Bone Defect.

Objective: To establish an objective animal experimental model for the experimental study of bone nonunion and detect the changes of endogenic of BMP-2 in area of bone defect. Methods: Select the pure big-ear Japan rabbits, cut off 1.0cm-bone segment (including periosteum ) from the middle part of radio of cubitus and seal the marrow cavity of fracture surfaces with bone wax, through general sample observation, histopathological and X-ray examination after the 4th, 6th and 8th week separately, to make sure the formation of bone nonunion and the tissue ingredients in fracture area, detect the changes of ingredients of BMP-2 in the tissues of bone-lacking area during different periods through immune examination. Results: General megascopic sample observation, X-ray examination and histopathological examination all show that the bone-lacking area is filled with fiber scar tissue without any bone tissue connection, the fracture surfaces ossify, the marrow cavity closes and there exists BMP-2 in bone-lacking which decreases with time. After the 4 th in area of bone defect,there exist BMP-2 in the intercellular substance and the chondrocyte of the neogenesis cartilage islands. Conclusion: The animal model established in the experiment have the general sample,image and pathological changes of bone nonunion and meet the demand of bone nonunion, which can be regarded as a reliable and practical experimental animal model of bone nonunion. In the oboslete tissue of bone-lacking area, the cell that was able to invert the bone tissue obviously decreased, which was a few in the area of newly formed bone. There also exist BMP-2 in the intercellular substance and the chondrocyte of the neogenesis cartilage islands, but the quantity is less. At the same time the experiment detects further that the BMP-2 in bone-lacking area decreases with time after four weeks and the farther the distance is with the fracture surface, the less the BMP-2 is, which provides experimental evidence for ectogentic cell genes to the concrescence of bone nonunion.