Tyagi S C, Meyer L, Schmaltz R A, Reddy H K, Voelker D J
Department of Internal Medicine, Biochemistry, Dalton Cardiovascular Research Center, University of Missouri-Health Sciences Center, Columbia, USA.
Atherosclerosis. 1995 Jul;116(1):43-57. doi: 10.1016/0021-9150(95)05520-7.
To understand the balance of proteinase antiproteinase activity and the production of extracellular matrix (ECM) at the site of arterial injury, we analyzed the composition of ECM and proteinase activity in normal internal mammary arteries, tissue samples obtained from atherosclerotic coronary lesions and restenotic lesions obtained during directional coronary atherectomy. Histologically and biochemically, collagen and proteoglycans increased, and elastin decreased in samples from restenotic lesions when compared to samples taken from patients undergoing their first revascularization (de novo). In contrast, cellularity was increased in samples obtained from de novo patients as compared to samples obtained from restenotic lesions. Intrinsic activity of matrix metalloproteinases (MMPs) was measured by using zymography and scanning all the lytic bands in zymographic gel. In these gels, identical amounts of total protein were loaded in each lane. MMP activity was determined as % of the total (latent and active) MMPs after trypsin activation (100%) in the normal artery. Intrinsic MMP activity was reduced to 6% +/- 1% in atherosclerotic lesions and 1% +/- 1% in restenotic lesions, when compared to activity found in normal (10% +/- 3%) arteries. Based on solubilization of fluorescein-conjugated elastin by the extracts, the MMP-mediated elastinolytic activity was 0.2 +/- 0.1, 8.8 +/- 1.5, and 24.0 +/- 3 nmol/min/mg in restenotic, native atherosclerotic and normal tissue, respectively. The results suggested that, in arterial tissue from patients with angiographic restenosis, there is an increased production of ECM collagen and a decrease in MMP activity compared to both normal artery and atherosclerotic samples from de novo patients undergoing an initial revascularization procedure of a significant coronary artery lesion.
为了解蛋白酶抗蛋白酶活性的平衡以及动脉损伤部位细胞外基质（ECM）的产生情况，我们分析了正常内乳动脉、从动脉粥样硬化性冠状动脉病变获取的组织样本以及定向冠状动脉斑块旋切术中获取的再狭窄病变中的ECM组成和蛋白酶活性。从组织学和生物化学角度来看，与首次血管重建（初发）患者的样本相比，再狭窄病变样本中的胶原蛋白和蛋白聚糖增加，弹性蛋白减少。相反，与再狭窄病变样本相比，初发患者样本中的细胞数量增加。通过酶谱法并扫描酶谱凝胶中的所有裂解带，测定基质金属蛋白酶（MMPs）的内在活性。在这些凝胶中，每条泳道加载等量的总蛋白。MMP活性以正常动脉中胰蛋白酶激活后（100%）的总（潜伏和活性）MMPs的百分比来确定。与正常动脉（10%±3%）中的活性相比，动脉粥样硬化病变中的内在MMP活性降至6%±1%，再狭窄病变中降至1%±1%。根据提取物对荧光素偶联弹性蛋白的溶解情况，再狭窄、天然动脉粥样硬化和正常组织中MMP介导的弹性蛋白溶解活性分别为0.2±0.1、8.8±1.5和24.0±3 nmol/min/mg。结果表明，与接受重大冠状动脉病变初次血管重建手术的初发患者的正常动脉和动脉粥样硬化样本相比，血管造影再狭窄患者的动脉组织中ECM胶原蛋白产生增加，MMP活性降低。
