title: Blood modulates the kinetics of reactive oxygen release in pancreatic ischemia-reperfusion injury.
abstract: OBJECTIVE
  Reason for the unsuccessful use of antioxidants in transplantation might be the unknown kinetics of reactive oxygen species (ROS) release. In this study, we compared the kinetics of ROS release from rat pancreata in the presence and absence of blood.
  
  
  METHODS
  In vivo, ischemia-reperfusion injury (IRI) was induced in pancreata of male Wistar rats by occlusion of the arterial blood supply for 1 or 2 hours. In vitro, isolated pancreata were single-pass perfused with Krebs-Henseleit bicarbonate solution. Reactive oxygen species were quantified by electron spin resonance spectroscopy using CMH (1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine) as spin label. Thiols (glutathione), nicotinamide adenine dinucleotide phosphate-oxidase activity, myeloperoxidase activity, and adenosine triphosphate content were measured.
  
  
  RESULTS
  During reperfusion, an increase in IRI-induced ROS in arterial blood was noted after 2 hours of warm ischemia. In sharp contrast, ROS release was immediate and short lived in blood-free perfused organs. The degree of tissue damage correlated with nicotinamide adenine dinucleotide phosphate-oxidase activity and adenosine triphosphate content. Antioxidative capacity of tissues was reduced.
  
  
  CONCLUSIONS
  Electron spin resonance spectroscopy in conjunction with spin labels allows for the detection of ROS kinetics in pancreatic IRI. Reactive oxygen species kinetics are dependent on the length of the ischemic period and the presence or absence of blood.
authors.affiliation: Department of Surgery, Albert-Ludwigs-University Freiburg, Hamburg, Germany. hannes.neeff@uniklinik-freiburg.de
authors.forename: Hannes P
authors.initials: HP
authors.lastname: Neeff
authors.forename: Olaf
authors.initials: O
authors.lastname: Sommer
authors.forename: Sebastian
authors.initials: S
authors.lastname: Meyer
authors.forename: Anja
authors.initials: A
authors.lastname: Tinelli
authors.forename: Moritz
authors.initials: M
authors.lastname: Scholtes
authors.forename: Ulrich T
authors.initials: UT
authors.lastname: Hopt
authors.forename: Oliver
authors.initials: O
authors.lastname: Drognitz
authors.forename: Ernst
authors.initials: E
authors.lastname: von Dobschuetz
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis; D000818:Animals; D001158:Arteries; D004578:Electron Spin Resonance Spectroscopy; D007700:Kinetics; D008297:Male; D019255:NADPH Oxidases / Q000378:metabolism; D010179:Pancreas / Q000098:blood supply* / Q000737:chemistry / Q000201:enzymology; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000097:blood*; D015427:Reperfusion Injury / Q000097:blood / Q000503:physiopathology*; D013113:Spin Labels; D013481:Superoxides / Q000097:blood
chemical_list: D017382:Reactive Oxygen Species; D013113:Spin Labels; D013481:Superoxides; D000255:Adenosine Triphosphate; D019255:NADPH Oxidases