Reilly J M, Brophy C M, Tilson M D
Department of Surgery, Washington University School of Medicine, St. Louis, Missouri 63110.
Ann Vasc Surg. 1992 Nov;6(6):499-502. doi: 10.1007/BF02000820.
Accumulating evidence suggests that abdominal aortic aneurysms (AAA) are due to a pathologic process which results in the destruction of aortic elastin and other matrix components. In this study, protein extractions were performed on both aneurysmal and normal aorta. Extracts were applied to frozen section of normal aorta either alone or in combination with 10 mM ethylenediaminetetraacetic acid, recombinant tissue inhibitor of metalloproteases, 10 mM zinc, and 5 mM phenylmethylsulfonyl fluoride, under conditions where calcium was removed from the buffer. After incubation, the sections were stained for elastin and evaluated by computerized morphometry. Aneurysm extracts, only in the presence of calcium, showed significant elastolytic activity characterized by destruction of intact elastic lamellae that was inhibited by ethylenediaminetetraacetic acid, the recombinant metalloprotease inhibitor, and zinc. Phenylmethylsulfonyl fluoride showed no inhibitory activity. Healthy aortic extract showed no elastolytic activity. This inhibitory profile is consistent with a metalloenzyme. We conclude that aneurysmal aorta contains elastolytic activity that is secondary to a metalloenzyme which is not present in normal aorta. This activity may play a role in the destruction of the elastin matrix that is seen in AAA's.
越来越多的证据表明，腹主动脉瘤（AAA）是由一种病理过程导致的，该过程会破坏主动脉弹性蛋白和其他基质成分。在本研究中，对动脉瘤主动脉和正常主动脉都进行了蛋白质提取。提取物单独或与10 mM乙二胺四乙酸、重组金属蛋白酶组织抑制剂、10 mM锌和5 mM苯甲基磺酰氟一起应用于正常主动脉的冰冻切片，条件是从缓冲液中去除钙。孵育后，对切片进行弹性蛋白染色并通过计算机形态学评估。仅在有钙存在的情况下，动脉瘤提取物显示出显著的弹性蛋白酶活性，其特征是完整弹性膜的破坏，这种破坏被乙二胺四乙酸、重组金属蛋白酶抑制剂和锌所抑制。苯甲基磺酰氟没有显示出抑制活性。健康主动脉提取物没有显示出弹性蛋白酶活性。这种抑制模式与金属酶一致。我们得出结论，动脉瘤主动脉含有一种弹性蛋白酶活性，这种活性继发于正常主动脉中不存在的金属酶。这种活性可能在腹主动脉瘤中所见的弹性蛋白基质破坏中起作用。
