Experimental hypercholesterolemia differentially affects adventitial vasa vasorum and vessel structure of the left internal thoracic and coronary arteries.
OBJECTIVE
Atherosclerosis is a chronic and diffuse disease that affects all vascular beds. However, some vascular beds are more prone to atherosclerosis than others. Recent evidence suggests a role for the vasa vasorum in the atherosclerotic process. We hypothesized that there is a difference in adventitial vasa vasorum structure between the left internal thoracic artery and the coronary artery. Hence the current study was designed to characterize and compare the structure of the adventitial vasa vasorum in the left internal thoracic and coronary arteries.


METHODS
Samples of vessels were obtained from female crossbred domestic pigs maintained on a normal (n = 6) or high-cholesterol (n = 6) diet for 12 weeks. The samples were scanned with micro-computed tomography, and the tomographic images were reconstructed and analyzed to obtain lumen area, vessel wall area, vasa vasorum count, vasa vasorum density, mean diameter of first- and second-order vasa vasorum, and second-order/first-order vasa vasorum ratio.


RESULTS
Vasa vasorum density was significantly higher in the coronary arteries versus that seen in the left internal thoracic arteries in the normal group, as well as in the high-cholesterol group. The higher vasa vasorum density in the high-cholesterol group versus that in the normal group was significant for both vessels, being more pronounced in the left internal thoracic artery. Lumen area and second-order/first-order vasa vasorum ratio were higher in the high-cholesterol group than in the normal group only in the left internal thoracic artery.


CONCLUSIONS
This study demonstrated that low vasa vasorum spatial density and higher lumen area observed in the left internal thoracic artery compared with that seen in the native coronary artery can be the structural background for the low incidence of atherosclerosis in this vessel.
Galili
Offer
O
Division of Cardiovascular Diseases, Mayo College of Medicine, Rochester, MN 55905, USA.
Sattler
Katherine J
KJ
Herrmann
Joerg
J
Woodrum
Julie
J
Olson
Monica
M
Lerman
Lilach O
LO
Lerman
Amir
A
D000818:Animals; D001161:Arteriosclerosis / Q000473:pathology; D003324:Coronary Artery Disease / Q000473:pathology; D003331:Coronary Vessels / Q000473:pathology*; D004547:Elastic Tissue / Q000473:pathology*; D005260:Female; D006937:Hypercholesterolemia / Q000473:pathology*; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008323:Mammary Arteries / Q000473:pathology*; D008852:Microradiography; D016328:NF-kappa B / Q000032:analysis; D013552:Swine; D014057:Tomography, X-Ray Computed / Q000379:methods; D014651:Vasa Vasorum / Q000473:pathology*; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis
D016328:NF-kappa B; D042461:Vascular Endothelial Growth Factor A