Aortic Enzyme Activity in Symptomatic and Asymptomatic Atherosclerotic Aneurysms

Abstract

In the present study, the role of advanced atherosclerosis in increased aortic protease content was evaluated. Forty samples of normal and atherosclerotic aortas and of infrarenal aneurysms were assayed for collagenase and elastase.

Both enzymes proved to have similar activity in normal and atherosclerotic tissue, whereas aneurysms revealed significantly elevated protease content. Preoperative symptoms increased the elastase activity: 6.58 ± 1.58 mU/g were extracted from symptomatic aneurysms in comparison with 2.51 ± 0.57 mU/g from asymptomatic aneurysms. Showed a high correlation (r = 0.96; p<0.01) with the erythrocyte sedimentation rate (ESR) preoperatively.

The data suggest that advanced atherosclerosis in aneurysm samples does not enhance the proteolysis of the aortic wall. Thus, the greater protease amount found in infrarenal aortic specimens may be linked to a more rapid fiber metabolism as compared with the thoracic aorta. High elastase content, detect ed in symptomatic infrarenal aneurysms, seems to be correlated with accelerat ed ESR.