Department of Orthodontics, Dental Clinic, University of Bonn, Welschnonnenstr. 17, 53111 Bonn, Germany.
Arch Oral Biol. 2010 Mar;55(3):215-22. doi: 10.1016/j.archoralbio.2010.01.002. Epub 2010 Feb 8.
To characterize in vivo the role of IGF-I and its signalling, as an early reaction in the mechanotransduction process and to analyse changes of the local expression related to the magnitude of the applied force.
Forces of 0.1N, 0.25 N and 0.5 N were applied to move the right upper first molars of 12 anaesthetized rats mesially. These forces were kept constant for 4h. The untreated contralateral side served as a control. Paraffin-embedded sections of the resected jaws were prepared for immunohistochemistry to localize insulin-like growth factor-I (IGF-I), its receptor (IGF-IR), and insulin receptor substrate 1 (IRS1). Histomorphometric analysis was performed to count the percentage of immunoreactive cells in different parts of the periodontal ligament.
IGF-I, IGF-IR and IRS1 positive cells were observed in the periodontal tissues of the control and loaded teeth. In the experimental group, the number of IGF-I-, IGF-IR- and IRS1-positive cells increased significantly on the tension side and decreased on the compression side.
These data indicate a close relationship between mechanical loading of the PDL and the autocrine/paracrine expression of IGF components as an early step in the mechanotransduction process leading in the long term to an organized remodelling of the alveolar bone.
在体内对 IGF-I 及其信号传导进行特征分析，将其作为机械转导过程中的早期反应，并分析与所施加力的大小相关的局部表达变化。
对 12 只麻醉大鼠右侧上颌第一磨牙施加 0.1N、0.25N 和 0.5N 的力，使其向近中移动。这些力持续 4 小时。未处理的对侧作为对照。切除的颌骨的石蜡包埋切片用于免疫组织化学，以定位胰岛素样生长因子-I（IGF-I）、其受体（IGF-IR）和胰岛素受体底物 1（IRS1）。进行组织形态计量学分析，以计算牙周韧带不同部位免疫反应性细胞的百分比。
在对照组和加载牙齿的牙周组织中观察到 IGF-I、IGF-IR 和 IRS1 阳性细胞。在实验组中，张力侧 IGF-I、IGF-IR 和 IRS1 阳性细胞的数量显著增加，而压缩侧则减少。
这些数据表明，PDL 的机械加载与 IGF 成分的自分泌/旁分泌表达之间存在密切关系，这是机械转导过程中的早期步骤，最终导致牙槽骨的有序重塑。
