增龄因素对鼠牙周组织骨保护素表达的影响

目的 比较幼年鼠和成年鼠牙周组织骨保护素(Osteoprotegerin,OPG)信使RNA(mRNA)表达的不同,以探讨增龄因素影响牙周组织改建的分子机制。方法 以4周(幼年鼠)和24周(成年鼠)雄性大鼠右上第一磨牙的牙周膜和邻近牙槽骨为实验对象,利用OPG多相寡核苷酸探针原位杂交检测实验部位OPG mRNA的表达。结果 1.幼年鼠近牙周膜的牙槽骨面可见破骨细胞和相应的骨陷窝;2.成年鼠牙周膜内细胞的OPG mRNA表达高于幼年鼠;3.鼠牙槽骨组织中,成年鼠和幼年鼠骨髓腔内均有OPGmRNA表达阳性的细胞,但成年鼠中的表达明显高于幼年鼠。结论 增龄因素使牙周组织内OPG表达明显增强,提示幼年的牙周组织较成年的牙周组织有较强的骨改建能力。

Effects of aging on osteoprotegerin expression in rat periodontal tissues

Objective To investigate the molecular mechanism of age-related effects on periodontal tissue turnover, we examined osteoprotegerin (OPG) mRNA expression in young and aged rat periodontal tissues. Methods Three 4-week-old (young group) and three 24-week-old (aged group) male rats were used. Alveolar bones with the right upper first molars were prepared for examining the expression of OPG mRNA in periodontal tissues by means of in situ hybridization. Results 1. There were several osteoclasts located in the related bone resorbing lacunae of young rat alveolar bones adjacent to periodontal tissues. 2. Periodontal ligament cells in aged rats expressed higher level of OPG mRNA than those in young rats. 3. OPG expression positive cells were detected in alveolar bone marrow canals of both young and aged rats. But the expression in aged alveolar bones was much stronger than that in young ones. Conclusion Aging enhances the expression of OPG in periodontal tissues. It suggests that young periodontal tissue play a more active role in bone remodeling.