骨形态发生蛋白-2在牙发育各阶段中的表达

Expression and significance of bone morphogenetic protein-2 in each stage of tooth development

目的观察骨形态发生蛋白(BMP)-2在牙发育各阶段中的表达,探讨其作用和意义。方法采用免疫组化法观察BMP-2在8～36周龄的人胎儿牙胚、出生1～22d的乳鼠和出生6周至5个月的犬乳牙发育中的表达。结果BMP-2在胎儿蕾状期和帽状期牙蕾上皮、牙板、成釉器和内外釉上皮均为阳性,在钟状期内釉细胞、中间层、成釉细胞和成牙本质细胞为强阳性,在牙乳头和牙囊为阳性;在乳牙萌出前、萌出期的乳鼠以及生后6周犬牙的成釉细胞、成牙本质细胞、赫特维希上皮根鞘和牙囊为强阳性;在犬乳恒牙替换期的牙根、牙周膜以及靠近牙周膜的成骨细胞为阳性。结论BMP-2是牙发育的重要调控因子,参与牙胚细胞的分化、牙胚的形态发生、牙的萌出和乳恒牙替换各阶段的调控。

Objective Observing the function and meaning of bone morphogenetie protein （BMP）-2 expression in different stages of tooth germ development. Methods Applied immunohistoehemieal techniques to examine the expression of BMP-2 in different stages of the tooth germs of human fetus in 8-36 weeks, the rat born after 1- 22 d, and the dog postnatal in 6 weeks to 5 months. Results BMP-2 expressed in all stages of every tooth germ. In human fetus, the positive reaction observed in epithelium of tooth bud, dental plate, enamel organ, external and outer enamel epithelium, dental papilla and dental follicle at bud stage and cap stage. While at bell stage cells in external enamel, stratum intermedium cell, ameloblasts and odontoblasts showed strong positive expression. The ameloblasts, odontohlasts, Hertwig epithelial root sheath and dental folliele showed strong positive reaction in the unerupted human deciduous tooth, the tooth under the eruption of neonate rat and 6 week＇s postnatal canal tooth. Positive expressions of BMP-2 were observed in root of tooth, peridental ligament and the osteoblasts adjoin to peHdental ligament in the dog succession of deciduous teeth. Conclusion BMP-2 is one of critical regulators in tooth development, which regulate the differentiation and morphogenesis of tooth germ cells and control the eruption of teeth and succession of deciduous teeth at different stages.