实验性牙根吸收组织中基质金属蛋白酶-1及其抑制剂-1的定位表达

The expression of matrix metalloproteinase-1 and tissue inhibitors of metalloproteinase-1 in the experimental root resorption tissue

目的检测小型猪实验性牙根吸收组织中基质金属蛋白酶(MMP)-1及基质金属蛋白酶抑制剂(TIMP)-1的表达,探讨二者在牙根吸收过程中的作用。方法选用6头小型猪的12颗下颌乳侧切牙,随机分为4组,每组3颗下颌乳侧切牙,分别加力0、0.98、1.96、2.94 N,每2周加力1次。第1次加力后45 d切取标本,应用SABC免疫组化方法检测MMP-1及TIMP-1在根吸收区牙周组织中的定位表达。结果加力0.98、1.96、2.94 N时牙根吸收区牙周组织中MMP-1阳性染色均比不加力强,加力0.98、1.96 N时牙根吸收区牙周组织中TIMP-1阳性染色均比不加力强。结论MMP-1与TIMP-1参与细胞外基质的代谢活动;MMP-1与TIMP-1在根吸收活动中起着重要的作用。

Objective To investigate the expression and the localization of the matrix metalloproteinase-1 （MMP-1） and tissue inhibitors of metalloproteinase-1 （TIMP-1）in root resorption tissue, and to elucidate the molecular changes and mechanism of root resorption induced by orthodontic force in order to establish a foundation for systemic study and prevention of root resorption in clinic. Methods Six experimental Chinese miniature pigs provided by Beijing Agricultural College were selected. Twelve mandibular deciduous lateral incisors of these six pigs were divided into four groups at random, and forces of 0, 0.98, 1.96, 2.94 N were put on each group respectively. The forces were exerted every two weeks. The animals were killed after forty-five days, and the specimens were made which were observed by light microscope. The ceils in root resorpion tissue that produced MMP- 1 or T/MP-1 were identified using immunohistoehemistry. Resuits The expression of MMP-1 in root resorption tissue in Group 0.98 N, Group 1.96 N and Group 2.94 N increased evidently compared with Group 0 N, and the expression of TIMP-1 in root resorption tissue in Group 0.98 N and Group 1.96 N increased evidently compared with Group 0 N. But the expression of TIMP-1 in root resorption tissue in Group 2.94 N had no difference with Group 0 N. Conclusion MMP-1 and TIMP-1 participate in the normal physiological metabolization of extracellular matrix and the normal remodeling of periodontal tissue during teeth movement on orthodontics treatment MMP- 1 and TIMP-1 play a significant role during root resorption.