出生后小鼠第一磨牙牙胚不同发育阶段的Notch1的表达

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Expression of Notch1 at different developmental stages of tooth germ of first molar of postnatal mouse

Objective To analyze the expression of Notch1 in the first molar tooth germ of postnatal mouse at different stages of tooth development and to further indicate the role of Notch signaling in the tooth development,especially in the tooth root development.Methods The expression levels of Notch1 were detected in the first molar tooth germ of the mouse during postnatal stages PN1（1 day）,PN3,PN5,PN7,PN10,PN14,and PN21 by Western blot.β-actin was used for reference.Bands intensities were compared using NIH ImageJ software.The statistical software package SPSS 11.0 was used for the statistical analysis.Results Expression of Notch 1 was strong at PN1 and PN3 stages.In PN5 and PN7,Notch1 expression decreased rapidly,but increased in PN10 and then decreased slightly in PN14,and dropped to its lowest level in PN21 when it could still be detected in a weak fashion.Conclusions Notch1 signaling continued its role in tooth development in mouse postnatal stages.In PN1 and PN3 of mouse,Notch1 signaling might be in active status because the crown of the first molar began its calcification.In PN10,Notch1 signaling was initiated again to was involve in the root formation.Notch1 might play a role in the reparation of dental pulp after completion of root formation since there was still Notch1 expression at that later tooth developmental stage.