Yonsei Med J.  1999 Jun;40(3):273-282. 10.3349/ymj.1999.40.3.273.

Ultrastructural changes of the external elastic lamina in experimental hypercholesterolemic porcine coronary arteries

• Kwon HM
• Kang S
• Hong BK
• Kim D
• Park HY
• Shin MS
• Byun KH

• KMID: 711648
• DOI: http://doi.org/10.3349/ymj.1999.40.3.273

Abstract

The external elastic lamina (EEL) serves as a barrier for cells and macromolecules between the media and adventitia in the vascular wall. We evaluated the morphological changes and quantitative assessments of the EEL architecture in the coronary circulation of pigs fed with a high cholesterol diet. Confocal microscopy analysis of the EEL from hypercholesterolemic coronary arteries revealed an altered pattern characterized by fragmentation and disorganization of the EEL associated with an increase in the thickness. Computerized digital analysis of the images obtained by confocal scanning microscopy demonstrated that compared to normal coronary arteries, the EEL of hypercholesterolemic coronary arteries decreased in the percentage of their elastin content (30.80 +/- 1.64% vs. 47.85 +/- 1.82%, p = 0.001). The percentage of elastin content was negatively correlated with the vessel wall area (r = -0.82, p = 0.001). The immunoreactivity for matrix metalloproteinase-3 (MMP-3) increased in cholesterol-fed coronary arteries, predominantly in the neointima and adventitia. This study demonstrates that experimental hypercholesterolemia induced ultrastructural changes of the EEL in coronary circulation. The EEL may also be an atherosclerosis-prone area compared with the intima. The EEL may play an important role in the development of structural changes which characterizes the early phase of coronary atherosclerosis and vascular remodeling.

Keyword

Hyperchlolesterolemia; EEL; vascular remodeling; confocal microscopy; MMP-3

MeSH Terms

Animal
Arteries/ultrastructure
Arteries/enzymology
Coronary Vessels/ultrastructure*
Coronary Vessels/enzymology
Elastic Tissue/ultrastructure*
Elastic Tissue/enzymology
Female
Hypercholesterolemia/pathology*
Hypercholesterolemia/enzymology
Stromelysin 1/metabolism
Swine