体外诱导培养大鼠牙乳头细胞碱性磷酸酶和Ⅰ型胶原的表达

Alkaline Phosphatase Activity and Ⅰ Collagen Expression of Rat Dental Papilla Cells in Virto

目的:观察体外诱导培养的大鼠牙乳头细胞碱性磷酸酶和I型胶原蛋白合成的变化。方法:原代培养法获得大鼠牙乳头细胞,在条件培养基中进行诱导培养,在不同时间进行钙结节染色,ALP染色和定量测定,ELISA法和RT-PCR法测定细胞I型胶原蛋白的量和mRNA表达水平。结果:体外诱导培养的大鼠牙乳头细胞形成含钙化物的细胞结节,体外培养至12d的诱导组细胞ALP高于对照组(P<0.05),细胞内I型胶原表达量高于对照组(P<0.05),且I型胶原mRNA表达水平上调(P<0.05);培养15d后诱导组细胞分泌的I型胶原高于对照组(P<0.05)。结论:大鼠牙乳头细胞在体外分化的过程中碱性磷酸酶活性明显增高,矿化能力增强,并不断合成和分泌I型胶原形成胞外基质。

Objective：To investigate the alkaline phosphatase（ALP）activity and typeⅠcollagen content of rat dental papillae cells（rDPC） cultured in odontoblast differentiation-inducing medium in vitro.Methods：Neonatal rat dental papillae cells were obtained from molar tooth germs and expanded in vitro.rDPC were cultured in the medium containing dexamethasone,ascorbic acid and β-glycerophosphate.Cell cultures were analysed for morphology,mineralization potential,alkaline phosphatase and Type I collagen using immunocytochemistry,ELISA and reverse transcriptase-polymerase chain reaction.Results：Cell mineral nodules of rDPC cultured in odontoblast differentiation-inducing medium were detect by Alizarin red S staining after day 7.ALP activity,type I collagen in cell culture supernatants and type I collagen mRNA expression of rDPC were all increased significantly compared with control group after day 12.Type I collagen concentrations in intracellular protein of differentiation-inducing cultured rDPC were significantly enhanced compared to rDPC in control group after day 15.Conclusion：Odontoblast differentiation-inducing treatment promoted the mineralization potential and differentiation of rDPC.