牙本质涎磷蛋白反义核酸对牙胚超微结构的影响  

Effects of Dentin Sialophosphoprotein Antisense Oligodeoxynucleotide on Ultrastructure of Mouse Tooth Germ

作　　者：张蓉 肖明振 赵守亮 徐平西[2] 张春宝 汪平 

机构地区：[1]第四军医大学口腔医院牙体病科,710032 [2]第四军医大学神经生物教研室

出　　处：《华西口腔医学杂志》2003年第4期281-283,共3页West China Journal of Stomatology

基　　金：国家自然科学基金 (编号 3980 0 1 55);全军"九五"重点课题 (编号 98Z0 82 )资助项目

摘　　要：目的　探讨牙本质涎磷蛋白 (DSPP)在牙胚发育和矿化中的作用及其机制。方法　胎龄为 17dBalb C胎鼠上颌第一磨牙 ,分为 2组 ,对照组牙胚置于无血清BGJb半固定培养基中培养 ;DSPP反义核酸组牙胚置于含有30 μmol L ,长 15bp的DSPP反义寡核苷酸的半固体培养基中培养。牙胚体外培养 10d后 ,进行透射电镜观察。 结果　 2组牙胚牙尖处成牙本质细胞中均含有大量的细胞器 ,线粒体肿胀 ,粗面内质网扩张 ,且DSPP反义核酸组成牙本质细胞中粗面内质网扩张更为明显 ;胞外基质超微结构显示 :对照组胶原纤维聚集成束 ,排列具有一定的方向 ,牙尖基质带平均厚度为 3μm ;DSPP反义核酸组胶原纤维粗细不等 ,排列紊乱 ,牙尖基质带平均厚度为 2 5 μm。 结论　DSPP可能通过控制成牙本质细胞正常的分泌功能、胶原纤维的正常形态和排列在牙胚生长、矿化中起重要作用。Objective To investigate more deeply the function and mechanism of DSPP during tooth development.Methods Explants of tooth germs from embryonic 17 th day mice were divided into two groups. In the control experiment, explants were cultured in agarose semi-solid medium under serum-free and chemically defined conditions, while explants in the other group were cultured with 30 μmol/L, 15 bp antisense oligodeoxynucleotide targeted to DSPP mRNA. After 10 ds, the explants were examined by transmission electron microscope. The width of dentin matrix at the tip of the cusps were then measured and statistically analyzed with Student t-test.Results Ultrastructure analyses showed that large cisternae of the rough endoplasmic reticulum (RER) existed in the odontoblasts at the tip of the cusps of antisense-treated explants and the average thickness of dentin matrix (2.5 μm) was thinner compared to the control ones (3 μm,P<0.001). In addition, the collagen fibers in extracellular matrix were disorganized.Conclusion These findings indicated that DSPP played an important role in keeping tooth normal development, as well as in dentin mineralization by maintaining odontoblasts′ secreting ability and controlling fiber structure and orientation.

关 键 词：牙本质涎磷蛋白 反义核酸 牙胚 超微结构 影响 

分 类 号：R780.2[医药卫生—口腔医学]