家兔慢性冬眠心肌MMP-2、MMP-9和TIMP-2表达与胶原重构

Collagen remodeling and expression of MMP-2,MMP-9 and TIMP-2 in chronic hibernating myocardium of rabbits

目的观察家兔慢性冬眠心肌(CHM)心肌间质胶原纤维变化及基质金属蛋白酶-2,9(MMP-2、MMP-9)及其抑制剂(TIMP-2)的表达。方法27只家兔随机分为模型组(CHM,n=15)及假手术组(SHAM,n=12)。观察心肌间质胶原容积百分比(ICVF)、Ⅰ型和Ⅲ型胶原纤维比例、计算Ⅰ/Ⅲ型胶原纤维比例记分(CRS);免疫组化染色及Western blot观察MMP-2、MMP-9及TIMP-2表达。结果与SHAM组相比,CHM组ICVF显著增加(P<0.01);Ⅰ/Ⅲ胶原比例增高;CRS显著增加(P<0.01);MMP-2及MMP-9的表达明显增多(P<0.01),TIMP-2的表达明显减少(P<0.01)。结论在CHM过程中,MMPs/TIMPs比例失平衡,可能是CHM间质胶原重构的机制之一。

Objective To observe the interstitial collagen and the expression of MMP-2, MMP-9 and TIMP-2 after chronic hibernating myocardium（CHM） in rabbits. Methods Twenty-seven rabbits,were divided into two groups： chronic hibernating myocardium group （ CHM, n = 15 ）, sham-operatioin group （ SHAM, n = 12 ）. The interstitial collagen volume fraction（ICVF） and the changes in the type and proportion of collagen fibers were observed. The expressions of MMP-2, MMP-9 and TIMP-2 were assessed by immunohistochemistry and Western bolt. Results Comparing with the SHAM group, ICVF; the ratio of collagen Ⅰto Ⅲ and collagen ratio score （CRS） and the expression of MMP-2 and MMP-9 were markedly increased （P 〈0. 01 ）in CHM group, while TIMP-2 was significantly decreased （P 〈 0. 01 ）. Conclusion During the progress of CHM, the balance of MMPs/TIMPs is broken, and this may be a potencial mechanism of interstitial remodeling.