基质金属蛋白酶-3和金属蛋白酶组织抑制因子-1在兔下颌牵张成骨改建期的表达及意义

目的　研究基质金属蛋白酶-3(MMP-3)和金属蛋白酶组织抑制因子-1(TIMP-1)在下颌骨牵张后形成的新骨组织中的定位表达。方法　对8只成熟大耳白兔按每天1 mm的牵张速率延长双侧下颌骨6 mm,在牵张结束后第4周处死动物,取牵张区新骨标本作组织学和免疫组化检测。结果　MMP-3与TIMP-1在牵张骨痂中均呈高水平表达,MMP-3阳性信号主要定位于新生骨小梁边缘的成骨细胞和埋入新骨基质中的骨细胞,TIMP-1则定位于成骨细胞。结论　MMP-3及TIMP-1可协同调节胞外基质的降解来影响牵张成骨的改建过程。

Expression of Matrix Metalloproteinase-3 and Tissue Inhibitor Metalloproteinases-1 in Regenerated Rabbit Bone after Mandibular Osteodistraction

Objective\ To observe the expression patterns of matrix metalloproteinase_3 and its inhibitor, tissue inhibitor metalloproteinases (TIMP)_1, in remodeling phase of mandibular distraction osteogenesis.Methods\ Bilateral mandibular osteotomies were performed in 8 mature rabbits. The mandibles were lengthened 6 mm using a custom_made distractor with a rate of 1 mm/d. All animals were killed in 4 weeks after completion of distraction. The distracted calluses were harvested and processed for histology and immunohistochemistry of MMP_3 and TIMP_1.Results\ Elevated expression of both MMP_3 and TIMP_1 was found in the distracted calluses resulting from mandibular lengthening. Positive staining for MMP_3 was seen in the osteoblasts and osteocytes, and TIMP_1 was mainly localized in osteoblasts.Conclusion\ MMP_3 and TIMP_1 appear to play important roles in the remodeling of new bone created by mandibular distraction osteogenesis.