%0 Journal Article %A Vanya Ilieva-Fartunova %A Galya Nikolova %A Donika Ivanova %A Antoaneta Zheleva %A Veselina Gadzheva %A Vanya Tsoneva %A Dimo Dimov %A Atanas Koychev %T Late-breaking abstract: Association of free radical formation and respiratory functional parameters in patients with chronic obstructive pulmonary disease: An electron paramagnetic resonance study %D 2014 %J European Respiratory Journal %P P3981 %V 44 %N Suppl 58 %X Oxidative stress plays an important role in the pathogenesis of COPD. The most modern and proper approach to detect oxidative stress and identify presence of free radicals in blood samples is the highly sensitive Electron paramagnetic resonance (EPR) spectroscopy technique. In the present study for the first time using EPR spectroscopy we determined some Real time markers of oxidative stress such as formation of Nitric oxide (NO·), Reactive oxygen species (ROS) and Ascorbate radicals (Asc·) in 30 COPD patients in comparison with 20 healthy volunteers.Methods: The levels of NO· , ROS and Asc· were determinated ex vivo at room temperature on EPR spectrometer, Bruker, Germany.Results: NO· radicals registered in COPD patients were significantly higher compared to the controls (p= 0.0001). Statistical significant increased production of ROS in COPD patients were also found comparing to those in the controls (p=0.001). Another confirmation for radical generation in COPD patients were significantly higher levels of ascorbate radicals (Asc·) comparing to controls (p<0.05). Radical levels were related to smoking habits and disease severity. Moreover, the levels of NO· showed a positive relationship with respiratory functional parameter FEV1 (r=0.55).Conclusion: In view of the facts that patients with COPD are in big risk of oxidative injury and the accumulation of free radicals may induce the inflammatory process, we can conclude that the NO· monitoring in blood may be a useful biomarker for early diagnosis of COPD development.Key words: COPD; Inflammation; Oxidative stress; Free radicals ROS; Asc·; NO·; EPR. %U