title: Differential distribution of vasa vasorum in different vascular beds in humans.
abstract: OBJECTIVE
  Vasa vasorum (VV) have been implicated to play a role in the pathogenesis of atherosclerosis. This study was designed to describe the distribution of VV density in different vascular beds in humans and to investigate the association between VV density and the known distribution of atherosclerosis in human arteries.
  
  
  METHODS
  Forty-two human arteries, harvested at autopsy or after explantation, were analyzed by three-dimensional microscopic-computed tomography (micro-CT). VV density, endothelial-surface-fraction (Sigma VV endothelial-surface-area/vessel-wall-volume) and vascular-area-fraction (Sigma VV area/vessel-wall-area) were calculated for coronary, renal and femoral arteries. Representatively five coronary, renal and femoral arteries were stained for endothelial cells (von Willebrand-Factor), macrophages (CD68), vascular endothelial growth factor (VEGF) and collagen (Sirius Red).
  
  
  RESULTS
  Coronary arteries showed a higher VV density compared to renal and femoral arteries (2.12+/-0.26 n/mm(2) versus 0.61+/-0.06 n/mm(2) and 0.66+/-0.11 n/mm(2); P<0.05 for both) as well as a higher endothelial-surface-fraction and vascular-area-fraction. Histology showed a positive correlation between histologically derived VV density and CD68-positive cells/area (r=0.54, P<0.01), VEGF-immunoreactivity/area (r=0.55, P<0.01) and a negative correlation between VV density and collagen I content (r=0.66, P<0.05).
  
  
  CONCLUSIONS
  This micro-CT study highlights a higher VV density in coronary than in peripheral arteries, supporting the relation between VV density and the susceptibility to atherosclerosis in different vascular beds in humans.
authors.affiliation: Department of Internal Medicine, Division of Cardiovascular Diseases, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Heike A
authors.initials: HA
authors.lastname: Hildebrandt
authors.forename: Mario
authors.initials: M
authors.lastname: Gossl
authors.forename: Dallit
authors.initials: D
authors.lastname: Mannheim
authors.forename: Daniele
authors.initials: D
authors.lastname: Versari
authors.forename: Joerg
authors.initials: J
authors.lastname: Herrmann
authors.forename: Danny
authors.initials: D
authors.lastname: Spendlove
authors.forename: Thomas
authors.initials: T
authors.lastname: Bajanowski
authors.forename: Nasser M
authors.initials: NM
authors.lastname: Malyar
authors.forename: Raimund
authors.initials: R
authors.lastname: Erbel
authors.forename: Lilach O
authors.initials: LO
authors.lastname: Lerman
authors.forename: Amir
authors.initials: A
authors.lastname: Lerman
mesh_terms: D000368:Aged; D000792:Angiography; D001158:Arteries / Q000378:metabolism / Q000473:pathology*; D050197:Atherosclerosis / Q000000981:diagnostic imaging* / Q000473:pathology*; D003094:Collagen / Q000378:metabolism; D003331:Coronary Vessels / Q000378:metabolism / Q000473:pathology; D005260:Female; D005263:Femoral Artery / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008264:Macrophages / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012077:Renal Artery / Q000378:metabolism / Q000473:pathology; D014057:Tomography, X-Ray Computed; D014651:Vasa Vasorum / Q000000981:diagnostic imaging* / Q000473:pathology*
chemical_list: D003094:Collagen