Effects of dentin sialophosphoprotein antisense oligodeoxynucleotide on ultrastructure of mouse tooth germ
Zhang, R.; Xiao, M.; Zhao, S.
Hua Xi Kou Qiang Yi Xue Za Zhi 21(4): 281-283
2003
ISSN/ISBN: 1000-1182 PMID: 14513583 Document Number: 561614
To investigate more deeply the function and mechanism of DSPP during tooth development. Explants of tooth germs from embryonic 17th 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 mumol/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. 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 microns) was thinner compared to the control ones (3 microns, P < 0.001). In addition, the collagen fibers in extracellular matrix were disorganized. 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.