title: Endothelial dysfunction of bypass graft: direct comparison of in vitro and in vivo models of ischemia-reperfusion injury.
abstract: BACKGROUND
  Although, ischemia/reperfusion induced vascular dysfunction has been widely described, no comparative study of in vivo- and in vitro-models exist. In this study, we provide a direct comparison between models (A) ischemic storage and in-vitro reoxygenation (B) ischemic storage and in vitro reperfusion (C) ischemic storage and in-vivo reperfusion.
  
  
  RESULTS
  Aortic arches from rats were stored for 2 hours in saline. Arches were then (A) in vitro reoxygenated (B) in vitro incubated in hypochlorite for 30 minutes (C) in vivo reperfused after heterotransplantation (2, 24 hours and 7 days reperfusion). Endothelium-dependent and independent vasorelaxations were assessed in organ bath. DNA strand breaks were assessed by TUNEL-method, mRNA expressions (caspase-3, bax, bcl-2, eNOS) by quantitative real-time PCR, proteins by Western blot analysis and the expression of CD-31 by immunochemistry. Endothelium-dependent maximal relaxation was drastically reduced in the in-vivo models compared to ischemic storage and in-vitro reperfusion group, and no difference showed between ischemic storage and control group. CD31-staining showed significantly lower endothelium surface ratio in-vivo, which correlated with TUNEL-positive ratio. Increased mRNA and protein levels of pro- and anti-apoptotic gens indicated a significantly higher damage in the in-vivo models.
  
  
  CONCLUSIONS
  Even short-period of ischemia induces severe endothelial damage (in-vivo reperfusion model). In-vitro models of ischemia-reperfusion injury can be limitedly suited for reliable investigations. Time course of endothelial stunning is also described.
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
authors: Gábor
authors: G
authors: Veres
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany; Heart Center, Semmelweis University, Budapest, Hungary.
authors: Péter
authors: P
authors: Hegedűs
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
authors: Enikő
authors: E
authors: Barnucz
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
authors: Raphael
authors: R
authors: Zöller
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
authors: Stephanie
authors: S
authors: Klein
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
authors: Harald
authors: H
authors: Schmidt
authors: Heart Center, Semmelweis University, Budapest, Hungary.
authors: Tamás
authors: T
authors: Radovits
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
authors: Sevil
authors: S
authors: Korkmaz
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
authors: Matthias
authors: M
authors: Karck
authors: Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
authors: Gábor
authors: G
authors: Szabó
mesh_terms: D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology / Q000637:transplantation; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D005786:Gene Expression Regulation; D006997:Hypochlorous Acid / Q000494:pharmacology; D020287:In Situ Nick-End Labeling; D008297:Male; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism; D010100:Oxygen / Q000494:pharmacology; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000235:genetics / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011917:Rats, Inbred Lew; D015427:Reperfusion Injury / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction; D046509:Tissue Culture Techniques; D014183:Transplantation, Heterologous; D014664:Vasodilation / Q000187:drug effects
chemical_list: D019408:Platelet Endothelial Cell Adhesion Molecule-1; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D006997:Hypochlorous Acid; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat; D053148:Caspase 3; D010100:Oxygen