Liu Yi, Chen Gang, Li Hong-jie, Wang Jian, Liu Yan-shan, Wang Zhi-qi
Dept. of Oral and Maxillofacial Surgery, Stomatological Hospital of Tianjin Medical University, Tianjin 300070, China.
Hua Xi Kou Qiang Yi Xue Za Zhi. 2010 Aug;28(4):425-9.
To study the expression and distribution of bone morphogenetic protein (BMP) in newly formed bone by distraction osteogenesis (DO), and to explore the mechanism of the DO bone formation and remodeling.
The cleft palate (CP) experimental animal models (23 Rhesus monkeys) were established surgically. In experimental group (21 Rhesus monkeys), the palatal defects were corrected by means of DO at the rhythm of 0.4 mm twice per day. The specimens were retrieved under euthanasia at 1, 2, 4, 6, 8, 12, 24 weeks intervals respectively in retention period. BMP immunohistochemical study was then performed. The blank control and experimental group (each of 2 animals) were set for comparison study.
The immunohistochemical study showed that BMP existed mainly in cytoplasma of osteoblasts, during the process of new bone formation. In early stage of 1 or 2 weeks, abundant osteoblasts aggregating on surfaces of the new bone trabeculae with positive DAB dye were observed. Through 4 to 6 weeks, the proliferative osteoblasts with very strong positive DAB dye indicating BMP expression were recorded. From 8 to 12 weeks, the expression of BMP and quantity of osteoblasts decreased gradually while more matured new bone structures were observed.
During the whole retention period, the expression of BMP showed a tendency from weak to strong and then to final cessation, this indicated a process of formation, remodeling and maturation of osteogenesis.
研究骨形态发生蛋白（BMP）在牵张成骨（DO）新形成骨中的表达及分布，探讨DO骨形成和重塑的机制。
通过手术建立腭裂（CP）实验动物模型（23只恒河猴）。实验组（21只恒河猴）采用每天2次、每次0.4mm的牵张速率对腭部缺损进行DO矫治。在保持期分别于1、2、4、6、8、12、24周间隔时间点对动物实施安乐死后取材，然后进行BMP免疫组织化学研究。设置空白对照组和实验组（各2只动物）进行对比研究。
免疫组织化学研究显示，在新骨形成过程中BMP主要存在于成骨细胞的细胞质中。在1或2周的早期，观察到大量成骨细胞聚集在新骨小梁表面，DAB染色呈阳性。在4至6周时，记录到增殖的成骨细胞DAB染色呈极强阳性，表明有BMP表达。从8至12周，BMP的表达和成骨细胞数量逐渐减少，同时观察到更成熟的新骨结构。
在整个保持期内，BMP的表达呈现出由弱变强然后最终停止的趋势，这表明了一个成骨的形成、重塑和成熟过程。
