应力对人牙周膜成纤维细胞Ⅰ型胶原和纤连蛋白mRNA表达的影响

Regulation of collagen type Ⅰ and fibronectin mRNA expression by mechanical stress in cultured haman periodontal ligament fibroblasts

目的 探讨机械应力下人牙周膜成纤维细胞（human periodontal ligament fibroblasts，hPDLF）Ⅰ型胶原和纤连蛋白mRNA表达的变化，为阐明力信号的细胞内转导机制提供依据。方法对体外培养的hPDLF分别施加不同动态张、压应力（强度为1000、2000、4000μstrain，加力时间为0、0．5、1、4、8、12h），定量聚合酶链反应（PCR）检测Ⅰ型胶原和纤连蛋白mRNA表达。结果随时间延长1000μstrain张应力和压应力均使Ⅰ型胶原和纤连蛋白mRNA表达增强，2000恤strain和4000μstrain张应力均使Ⅰ型胶原mRNA表达先增强1h后减弱，而2000μstrain和4000μstrain压应力均使Ⅰ型胶原mRNA表达持续减弱，2000μstrain张应力和压应力均使纤连蛋白mRNA表达持续增强，而4000μLstrain张应力和压应力均使纤连蛋白mRNA表达先增强4h后减弱。结论本项实验提供的应力范围内动态张应力和压应力刺激可改变hPDLF Ⅰ型胶原和纤连蛋白mRNA的表达。

Objective To investigate the effect of different dynamic tensional and compressive stress on the mRNA expression of collagen type I and fibronectin in cultured human periodontal ligament fibroblasts （hPDLF）, and explore the regularity of functional change in hPDLF. Methods A new cyclic strain loading apparatus was used for mechanically loading. Cells cultured in vitro were loaded with three levels （1000 μstrain, 2000μstrain, 4000μstrain） of tensional and compressive forces and collected at different time （0 h,0. 5 h,1 h,4 h,8 h,12 h） course after strain loading. The quantity of collagen type Ⅰ and fibronectin mRNA was analyzed by means of quantitative real-time PCR with special primers of up- and down-regulated genes. Data were analyzed using SPSS version 10. 0 software. Results Different magnitude and different kinds of mechanical forces as well as the force application time significantly changed the expression of collagen type Ⅰ and fibronectin mRNA in hPDLF. Conclusions Dynamic mechanical forces could regulate the expression of collagen type Ⅰ and fibronectin mRNA in hPDLF. Collagen type Ⅰand fibronectin participated in the mechanical signal transduction in human periodontal ligament fibroblasts.