体外培养的冠髓和根髓细胞中碱性磷酸酶的活性

目的：比较根部和冠部牙髓培养细胞的碱性磷酸酶活性，探讨牙髓干细胞在牙髓中的定位。方法：用组织块法分别培养根髓、冠髓细胞，用Gomori碱性磷酸酶染色法对根、冠髓培养细胞在加入条件孵育液(20％DMEM 10nmol／L地塞米松 10mmol/L β-甘油酸钠 50mg／L L-抗坏血酸)后的第5、10、15天的碱性磷酸酶活性进行测定，从牙髓干细胞的功能角度，探讨其在牙髓中的定位。结果：根髓、冠髓细胞均出现碱性磷酸酶染色阳性，染色强度在第5天无差别，在第10、15天根髓染色强度大于冠髓。结论：碱性磷酸酶的活性在根髓中大于冠髓。牙髓干细胞可能存在于全部牙髓之中．其密度在根髓中大于冠髓。

The ALP activity of cultured dental coronal and root pulp cells in vitro

PURPOSE: To compare the ALP activity in human dental coronal and root pulp,and investigate the localization of dental pulp stem cells in the dental pulp. METHODS: The human dental root and coronal pulp cells were cultured in tissue-explant method,the 5th generation of cells in good growth condition were subcultured with conditioned media(20%DMEM+10nmol/L +dexamethaone+50mg/L ascorbic acid) to induce mineralization. At the days of 5,10,15 after inducing, Gomori alkaline phosphatase stain was used to investigate alkaline phosphatase (ALP) activity in root and coronal pulp cells. RESULTS: Positive staining was found in both root and coronal cells, the ALP activity was equal at 5 days of incubation,but higher in root pulp cells than that of coronal pulp cells after 10 and 15 days of incubation. CONCLUSIONS: ALP activity in dental root pulp is higher than that in coronal pulp. DPSCs may exist in both dental root and coronal pulp, and the density of DPSCs is higher in the root pulp than the coronal pulp.