title: Localization of deoxyglucose and annexin A5 in experimental atheroma correlates with macrophage infiltration but not lipid deposition in the lesion.
abstract: OBJECTIVE
  The aim of this study was to understand the relationship of lipid deposition to the macrophage content, macrophage metabolism, and apoptosis in plaque. We compared the uptake of 2-deoxy-2-fluoro-D-[(14)C]glucose ([(14)C]FDG) and [(99m)Tc]HYNIC-annexin V ([(99m)Tc]annexin A5) with the lesion histology in apolipoprotein E knockout (apoE(-/-)) mice.
  
  
  METHODS
  Male apoE(-/-) mice (n = 9) were injected with [(14)C]FDG and [(99m)Tc]annexin A5. Cryostat sections of aorta samples (n = 49) were used for dual-tracer autoradiography, and regional tracer uptake levels were evaluated. Lesions were identified histologically with Movat's pentachrome (AHA lesion phenotypes), Mac-2 staining (macrophage infiltration) and Oil Red O staining (lipid deposition).
  
  
  RESULTS
  The highest uptakes of [(14)C]FDG (3.10 ± 1.50 %ID × kilogram per square millimeter) and [(99m)Tc]annexin A5 (0.49 ± 0.20 %ID × kilogram per square millimeter) were shown in atheromatous lesions (types III and IV). Each tracer uptake showed better correlation with macrophage infiltration than lipid deposition ([(14)C]FDG, r = 0.44 vs. r = 0.14; [(99m)Tc]annexin A5, r = 0.65 vs. r = 0.48).
  
  
  CONCLUSIONS
  Both tracers were concentrated in type III and IV atheromatous lesions which corresponded to macrophage infiltration rather than lipid deposition.
authors.affiliation: Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Kita-ku, Sapporo, Japan. zhaoyan@med.hokudai.ac.jp
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
authors.forename: Songji
authors.initials: S
authors.lastname: Zhao
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kuge
authors.forename: William H
authors.initials: WH
authors.lastname: Strauss
authors.forename: Francis G
authors.initials: FG
authors.lastname: Blankenberg
authors.forename: Nagara
authors.initials: N
authors.lastname: Tamaki
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000378:metabolism*; D001011:Aorta / Q000378:metabolism / Q000473:pathology; D001057:Apolipoproteins E / Q000172:deficiency / Q000378:metabolism; D001345:Autoradiography; D003847:Deoxyglucose / Q000378:metabolism*; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D050356:Lipid Metabolism; D008264:Macrophages / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D011877:Radionuclide Imaging; D012044:Regression Analysis; D013667:Technetium / Q000378:metabolism
chemical_list: D017304:Annexin A5; D001057:Apolipoproteins E; D019788:Fluorodeoxyglucose F18; D013667:Technetium; D003847:Deoxyglucose