title: Quantification of superoxide radical production in 4 vital organs of rats subjected to hemorrhagic shock.
abstract: OBJECTIVE
  The aim of this study was to measure the production of superoxide radical (O2-), a direct indicator of oxidative stress, in 4 vital organs of rats subjected to hemorrhagic shock. For this purpose, and for the first time, a new quantitative assay for the ex vivo measurement of O2- via an established 1:1 molar relationship between O2- and 2-OH-ethidium was used. The production of lipid hydroperoxides (LOOHs), a standard method of evaluation of oxidative stress, was also used for reasons of comparison.
  
  
  METHODS
  Sixteen male Wistar rats were divided into 2 groups: sham and hemorrhagic shock, targeting to a mean arterial pressure of 30 to 40 mm Hg for 60 minutes. Three hours after resuscitation, tissues were collected for measurement of LOOHs and O2- production.
  
  
  RESULTS
  Hemorrhagic shock induced increased production of LOOHs in the gut, liver, and lungs (P<.001), whereas the production of O2- was also increased in the gut (P<.001), liver (P<.001), and, to a lesser extent, in the lungs (P<.05). The oxidative load of the kidneys, as estimated by both techniques, remained unaffected.
  
  
  CONCLUSIONS
  The results of this new O2- assay were comparable with the results of the established LOOHs method, and this assay proved to be accurate and sensitive in the detection and quantification of O2- production in all organs tested. Thus, the proposed direct measurement of O2- in critically ill patients often facing in extremis situations could be used as a prognostic tool and as a method to evaluate therapeutic interventions in the setting of emergency medicine.
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, School of Medicine, 26500 Rion, Greece.
authors.forename: Eleftheria S
authors.initials: ES
authors.lastname: Panteli
authors.forename: Fotini
authors.initials: F
authors.lastname: Fligou
authors.forename: Chrisaugi
authors.initials: C
authors.lastname: Papamichail
authors.forename: Ioannis
authors.initials: I
authors.lastname: Papapostolou
authors.forename: Georgios
authors.initials: G
authors.lastname: Zervoudakis
authors.forename: Christos D
authors.initials: CD
authors.lastname: Georgiou
authors.forename: Kriton S
authors.initials: KS
authors.lastname: Filos
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D008054:Lipid Peroxides / Q000032:analysis / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012151:Resuscitation; D012771:Shock, Hemorrhagic / Q000378:metabolism* / Q000628:therapy; D013481:Superoxides / Q000032:analysis* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D008054:Lipid Peroxides; D013481:Superoxides