부산대학교 도서관

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. CONCLUSION:: 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.