中文摘要：

背景:研究影响牙周膜干细胞成骨分化的相关离子通道。目的:初步观察P2X7受体在人牙周膜干细胞成骨分化中的作用。方法:分离培养人牙周膜干细胞,分为4组,分别添加成骨诱导液和100 nmol/L三磷酸腺苷、成骨诱导液、100 nmol/L三磷酸腺苷及普通培养基培养,于成骨诱导7,14 d,利用茜素红染色检测成骨效果,q RT-PCR,Western blot检测OCN、Runx2以及P2X7受体的表达。结果与结论:茜素红染色显示成骨诱导液+三磷酸腺苷组牙周膜干细胞的成骨效果在7 d时显著好于成骨诱导液组,但在14 d时成骨诱导液组成骨效果显著好于成骨诱导液+三磷酸腺苷组(P【0.05);在成骨诱导7 d时,qR T-PCR结果显示成骨诱导液+三磷酸腺苷组Runx2,OCN mR NA的表达达到峰值,而14 d时明显降低(P【0.05)。成骨诱导7 d时,成骨诱导液+三磷酸腺苷组P2X7受体mR NA的表达量明显高于三磷酸腺苷组(P【0.05),成骨诱导液组和对照组未见P2X7受体mR NA的表达,成骨诱导14 d时,成骨诱导液+三磷酸腺苷组表达量下降,明显低于三磷酸腺苷组,差异有显著性意义(P【0.05)。Western blot结果显示,成骨诱导7 d时,成骨诱导液+三磷酸腺苷组P2X7受体的表达达到峰值,高于三磷酸腺苷组,而成骨诱导液组表达量低,对照组几乎没有表达;成骨诱导14 d时,成骨诱导液+三磷酸腺苷组P2X7受体的表达比7 d时明显下降,而三磷酸腺苷组P2X7受体的表达比7 d时有所增加。结果表明外源性三磷酸腺苷可在牙周膜干细胞成骨诱导前7 d明显提高成骨效果,但在7 d后,抑制成骨诱导效果,三磷酸腺苷可以激活牙周膜干细胞P2X7受体表达,且P2X7受体的表达与牙周膜干细胞的成骨效果正相关。

英文摘要：

BACKGROUND:Ion channels related to the osteogenic differentiation of periodontal ligament stem cels have been studied. OBJECTIVE:To preliminarily investigate the effect of P2X7 receptor on the osteogenic differentiation of human periodontal ligament stem cels. METHODS:Human periodontal ligament stem cels were isolated and divided into four groups, cultured in 100 nmol/L adenosine triphosphate+osteogenic medium, osteogenic medium, 100 nmol/L adenosine triphosphate, and normal culture medium (control group), respectively. After induction for 7 and 14 days, osteogenic effect was detected by alizarin red staining, and expressions of OCN, Runx2 and P2X7 receptor at mRNA and protein levels were analyzed by qRT-PCR and western blot assay, respectively. RESULTS AND CONCLUSION: Under alizarin red staining, the osteogenic effect of periodontal ligament stem cels was better in the group of adenosine triphosphate+osteogenic medium than the osteogenic medium group at
7 days, but it was better in the osteogenic medium group than the group of adenosine triphosphate+osteogenic medium at 14 days (P < 0.05). Results from qRT-PCR showed that, in the group of adenosine triphosphate+osteogenic medium, the mRNA expression of Runx2 and OCN reached peak at 7 days, but decreased significantly at 14 days (P < 0.05). The expression of P2X7 receptor mRNA in the group of adenosine triphosphate+osteogenic medium was significantly higher than that in the adenosine triphosphate group at 7 days (P < 0.05), but significantly lower than that in the adenosine triphosphate group at 14 days (P < 0.05). There was no expression of P2X7 receptor mRNA in the osteogenic medium group and control group. Western blot assay showed that at 7 days, the expression of P2X7 receptor peaked in the adenosine triphosphate+osteogenic medium group at 7 days, which was significantly higher than that in the adenosine triphosphate group, and there was a low expression of P2X7 receptor in the osteogenic medium group and no expression in the control group; at 14 days,