牙体机械损伤后牙本质牙髓组织MMP-2和MMP-9表达变化  

Expression of MMP-2 and MMP-9 in dentin-pulp complex after mechanical injury

作　　者：李昊妍[1] 陈颖[1] 张丹 梁景平[1] 

机构地区：[1]上海交通大学医学院第九人民医院牙体牙髓科上海市口腔生物工程重点实验室上海市口腔医学研究所,上海200011

出　　处：《上海交通大学学报（医学版）》2009年第5期504-508,共5页Journal of Shanghai Jiao tong University:Medical Science

基　　金：上海市科委重点项目(05JC14042);上海市重点学科建设项目资助(S30206)~~

摘　　要：目的研究牙体机械损伤后牙本质牙髓组织中基质金属蛋白酶-2(MMP-2)和基质金属蛋白酶-9(MMP-9)表达的变化。方法以离体第三磨牙(n=30)制作牙体机械损伤的牙本质牙髓复合体体外培养模型(模型组)。分别于培养后第3、7、14天收集样本,免疫组化染色、Real-time PCR和Western blotting检测MMP-2和MMP-9在培养后不同时间点的表达。以无牙体损伤的牙本质牙髓复合体培养的离体第三磨牙(n=30)作为对照组。结果免疫组化染色发现,MMP-2和MMP-9在对照组成牙本质细胞呈阳性表达,在牙髓细胞则呈阴性表达;在模型组,成牙本质细胞和牙髓细胞MMP-2和MMP-9均呈阳性表达。图像分析显示,模型组培养后各时间点MMP-2和MMP-9表达均显著高于对照组(P<0.05);且模型组培养第3天MMP-2和MMP-9表达均显著高于培养第7和第14天(P<0.05)。Real-time PCR检测表明,模型组培养后第3天的MMP-2和MMP-9 mRNA表达显著高于培养后第7和第14天(P<0.05)。Western blotting检测发现,模型组培养后各时间点均有MMP-2和MMP-9蛋白表达,以培养后第3天时较为明显。结论在牙体损伤的牙本质牙髓复合体培养过程中,MMP-2和MMP-9表达呈现先增加后减弱,与基质降解和合成的时间相对应。Objective To detect the expression of matrix metalloproteinase （MMP）-2 and MMP-9 in dentin-pulp complex after mechanical injury. Methods The in vitro culture models of dentin-pulp complex after mechanical injury were prepared with third molars（model group, n = 30）. Samples were collected 3, 7 and 14 d after culture, and immunohistochemical staining, Real-time PCR and Western blotting were employed to detect the expression of MMP-2 and MMP-9 at different time points after culture. And the third molars cultured in vitro with dentin-pulp complex without mechanical injury were served as controls（control group, n = 30）. Results It was revealed by immunohistochemical staining that MMP-2 and MMP-9 were positively expressed in odontoblasts and negatively expressed in pulp cells in control group, while both of them were positively expressed in odontoblasts and pulp cells in model group. The image analysis indicated that the expression of MMP-2 and MMP-9 was significantly higher in model group than that in control group at different time points after culture （P 〈 0.05）, and the expression of MMP-2 and MMP-9 was significantly higher on the third day after culture than that on the seventh day and fourteenth day after culture in model group（P 〈 0.05）. It was demonstrated by Western blotting that there was expression of MMP-2 and MMP-9 protein at different time points after culture, and that was most significant on the third day after culture. Conclusion The expression of MMP-2 and MMP-9 increases first and decreases then during culture of dentin-pulp complex after mechanical injury, which coincides with degradation and synthesis of extracellular matrix.

关 键 词：牙本质牙髓复合体 基质金属蛋白酶-2 基质金属蛋白酶-9 机械损伤 

分 类 号：R781.2[医药卫生—口腔医学]