title: Fe(III) distribution varies substantially within and between atherosclerotic plaques.
abstract: OBJECTIVE
  Vulnerable atherosclerotic plaques are structurally weak and prone to rupture, presumably due to local oxidative stress. Redox active iron is linked to oxidative stress and the aim of this study was to investigate the distribution of Fe(III) in carotid plaques and its relation to vulnerability for rupture.
  
  
  METHODS
  Atherosclerotic plaques from 10 patients (three asymptomatic and seven symptomatic) were investigated. Plaque vulnerability was classified using ultrasound and immunohistochemistry and correlated to Fe(III) measured by electron paramagnetic resonance spectroscopy.
  
  
  RESULTS
  Large intra-plaque Fe(III) variations were found. Plaques from symptomatic patients had a higher Fe(III) concentration as compared with asymptomatic plaques (0.36 ± 0.21 vs. 0.06 ± 0.04 nmol Fe(III)/mg tissue, P < 0.05, in sections adjoining narrowest part of the plaques). All but one plaque from symptomatic patients showed signs of cap rupture. No plaque from asymptomatic patients showed signs of cap rupture. There was a significant increase in cap macrophages in plaques from symptomatic patients compared with asymptomatic patients (31 ± 11% vs. 2.3 ± 2.3%, P < 0.01).
  
  
  CONCLUSIONS
  Fe(III) distribution varies substantially within atherosclerotic plaques. Plaques from symptomatic patients had significantly higher concentrations of Fe(III), signs of cap rupture and increased cap macrophage activity.
authors: Department of Medical and Health Sciences (IMH), Division of Radiological Sciences, Linköping University, Linköping, Sweden; Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden.
authors: H
authors: H
authors: Gustafsson
authors: M
authors: M
authors: Hallbeck
authors: M
authors: M
authors: Norell
authors: M
authors: M
authors: Lindgren
authors: M
authors: M
authors: Engström
authors: A
authors: A
authors: Rosén
authors: H
authors: H
authors: Zachrisson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D050197:Atherosclerosis / Q000175:diagnosis* / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D005260:Female; D006801:Humans; D007501:Iron / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014018:Tissue Distribution; D014463:Ultrasonography / Q000379:methods
chemical_list: D015415:Biomarkers; D007501:Iron