TIMP2在激素性股骨头坏死中作用的实验研究

摘要

目的：观察激素性股骨头坏死组织中基质金属蛋白酶抑制剂2(TIMP2)的表达情况，探讨TIMP2在激素性股骨头坏死中的作用机制。方法采用12只家兔，按照随机数表法分为对照组和模型组，每组6只。模型组给予静脉注射10µg· mL-1· kg-1内毒素和肌肉注射40 mg/kg甲基强的松龙，对照组给予等量的生理盐水。10周后进行X线、CT等检查，比较两组家兔的股骨头标本空骨陷窝率、髓腔脂肪面积及TIMP2表达。结果模型组家兔的空骨陷窝率为(20.26±9.83)%，髓腔脂肪面积为(236.30±34.78)µm2，X光可见股骨头内骨小梁稀疏，断裂，密度不均匀等坏死表现，TIMP2的阳性表达率为10.5%，而对照组则分别为(3.12±1.05)%、(178.80±21.82)µm2和30.5%，两组比较差异均具有统计学意义(P<0.05)。结论激素性股骨头坏死组织中的TIMP2的低表达与股骨头坏死发生有密切关系。%Objective To observe the expression of matrix metallo-proteinase inhibitor-2 (TIMP2) and its roles in glucocorticoid-induced osteonecrosis of the femoral head (GNFH). Methods Twelve rabbits were randomly divided into control group and model group according to random number table, with 6 rabbits in each group. The mod-el group was given intravenous injection of endotoxin (10 µg· mL-1· kg-1) and intramuscular injection of methylprednis-olone (40 mg/kg), while the control group was given equal amount of saline. The rabbits were examined by X ray and computed tomography (CT) 10 weeks later. The rates of empty bone lacuna, fat area of medullary cavity and TIMP2 ex-pression of femoral head specimens were observed and calculated. Results The rate of empty bone lacuna, the fat area of medullary cavity, the positive expression rate of TIMP2 were (20.26±9.83)%, (236.30±34.78)μm2, 10.5%, respectively in model group, which were significantly higher than those in control group of (3.12±1.05)%, (178.80±21.82)μm2, 30.5%(P<0.05). X ray showed necrosis manifestations of sparse bone trabecula in the femoral head, fracture and uneven density in model group. Conclusion Low expression of TIMP2 in GNFH is closely related to the occurrence of GNFH.