Investigation on mechano-receptor in the cell using rat periodontal ligament

本研究旨在建立研究牙周膜对动态应力反应的动物实验模型，并在牙周膜细胞中寻找将咬合负荷的物理应力转化为生化信号的机械受体。2004年，我们尝试建立动物模型。通过直径1mm的金属丝与大鼠上磨牙粘接，观察模拟咬合损伤的牙周韧带组织学变化。结果，牙周韧带从破坏过程转化为再生过程的时间可以被详细地检索出来。此外，我们选择了几种与骨相关的蛋白质，并对其抗体进行免疫组织化学处理。结果，骨桥蛋白的产生在破骨细胞中被上调。然后我们试图找到RANKL的产生，因为它被认为是作为上游细胞因子起作用，但我们找不到。这意味着骨桥蛋白的产生可能通过一种特殊的途径受到控制。在2005年和2006年，我们研究了无负荷条件下牙周韧带的组织学变化。由于没有装载机，我们选择了温度刺激代替机械刺激。因此，无法找到温度和机械刺激的共同特征。需要进一步的研究来更精确地比较这些。2007年，我们尝试建立动物模型来研究热对牙周韧带的影响，但由于无法制造出方便的设备，我们无法实现这一目标。进一步的研究是必要的。

The purpose of this research was to establish the animal experiment model for the investigation of periodontal ligament response to the dynamic stress, and to find mechano-receptor in the periodontal ligament cells that convert a physical stress of occlusal load to a biochemical signal.In 2004, we tried to establish an animal model. Through bonding 1 mm in diameter wire to the rat upper molar, histological changes in periodontal ligament could be investigated that was simulating occlusal trauma. As a result, the time that the periodontal ligament converted from the destruction process to the regenerative process was able to be retrieved in detail.In addition, we selected several kinds of proteins related to the bone, and immunohistochemistry was done using the antibody to these. As a result, the production of Osteopontin was up regulated in osteoclasts. Then we tried to find RANKL production because it is thought to be working as the upstream cytokine, but we could not. This means there might be a specific pathway through which Osteopontin production is controlled.In 2005 and 2006, we investigated histological changes of periodontal ligament under no loading condition. Because loading machine was not available, we selected the temperature stimulus instead of mechanical stimulation. As a result, the common feature of a temperature and mechanical stimulation cannot be found. Further study is required to compare these more precisely.In 2007, we tried to establish animal model that enables us to investigate thermal influences to the periodontal ligament, but we could not achieve because we could not fabricate a handy device for this purpose. Further study is necessary.