正畸力引起的牙周组织内肿瘤坏死因子-α含量变化的研究

Expression of Tumor Necrosis Factor- α in Orthodontic Tooth Movement in Rats

目的研究在正畸牙移动中牙周组织内肿瘤坏死因子-α（TNF-α）表达水平是否发生一定的变化。方法选取Wistar大鼠32只，分别以实时定量RT-PCR和Westernblotting的方法检测施加正畸力后1d、3d、7d和14d牙周组织内TNF-αmRNA含量和蛋白表达的变化。结果正畸力使牙周组织内TNF-αmRNA和蛋白含量均增加，这一含量的变化在1d时即已出现，7d时达到最高峰，之后下降，至14d时含量已降至接近1d时的水平。结论在正畸牙移动中，牙周组织内TNF-α含量变化明显，并有一定的时相特异性。TNF-α在正畸牙移动中可能具有一定的作用。

Objective To determine whether the expression of Tumor Necrosis Factor： α （TNF- α ）mRNA and protein are altered in orthodontic tooth movement.Methods Thirty-two Wistar rats were included in this study. Sentalloy closed-coil springs were placed to induce a mesial traction force on the lower right first molar. Animals were killed after 1, 3, 7 andl4days.The dental tissues were sampled for detecting TNF- α mRNA and protein by real-time RT-PCR and by Western blotting, respectively.Results Mechanical force triggered an increase of TNF- α mRNA and protein in the alveolar bone, periodontal ligament, and root tissues. The expression of TNF- α mRNA and protein increased from day 1, reached the peak on day 7, and then decreased. Conclusion The levels of TNF- α mRNA and protein increase during orthodontic tooth movement and fluctuate with different phases. TNF- α might play a role in orthodontic tooth movement.