The Study Of The Isoprostane F_2a-Ⅲ Levels In Urine And The Correlation With Artery Blood Gas Analysis In Chronic Obstructive Pulmonary Disease (COPD) Patients

Objects: Chronic obstructive pulmonary disease (COPD) is a chronic common disease that is characterised by incompletely reversibly airflow limitation,which is high morbidity and mortality.The pathogenesis are confusing unclear. The oxidative stress and persistent chronic inflammatory response in lung may play an important role in the pathogenetic mechanisms underlying COPD. Isoprostane F2а-Ⅲis one of important markers of oxidative stress. In this study,we investigated the levels of oxidative stress through assaying the levels of Isoprostane F2а-Ⅲin urine from control group and COPD patients. To make the correlation between the levels of Isoprostane F2а-Ⅲin urine and artery blood gas analysis in severe exacerbation, we may reveal to effect oxidative stress factor in the severe exacerbation COPD patients.Methods: 1. The lung function of 22 patients with COPD(severe exacerbation and stable stage) and 40 healthy volunteers which including 20 healthy smokers and 20 healthy non-smokers were tested by profile pulmonary function system(select the COPD of severe exacerbation can tolerance pulmonary function test).COPD patients in severe exacerbation need to do artery blood gas analysis by GEM preimer 3000 blood gas analyzer. Measure the creatinine in urine by trinitrophenal method. 2. A 12-h urine specimen was collected from COPD in severe exacerbation and stable stage, control group .The volume of urine was recorded and a 6ml aliquot was frozen at 80℃for later analysis. The Isoprostane F2а-Ⅲin urine was measured by enzyme immunoassay (EIA).Results: 1. In severe exacerbation of COPD group, the level of Isoprostane F2а-Ⅲwas significantly higher than stable stage of COPD group (166.17±94.68ng/mmol creatininel, 84.47±48.12ng/mmol creatinine respectively,P<0.05). 2. In COPD severe exacerbation and stable stage patients, the level of Isoprostane F2а-Ⅲwere significantly higher than healthy non-smokers {(166.17±94.68ng/mmol creatinine ,84.47±48.12ng/mmol creatinine, [M 32.25, 95%CI(27.06～46.04)]ng/mmol creatinine, respectively, P<0.05}. 3. In COPD severe exacerbation and stable stage patients, the level of Isoprostane F2а-Ⅲ(166.17±94.68 ng/mmol creatininel, 84.47±48.12ng/mmol creatinine) were not significantly different from the healthy smokers[M 99.17, 95%C(I96.79～145.35)]ng/mmol creatinine, P>0.05. 4. In healthy smokers, the level of Isoprostane F2а-Ⅲwas significantly higher than healthy non-smokers{[M 99.17, 95%CI(96.79～145.35)]ng/mmol creatinine, [M 32.25,95%CI(27.06～46.04)]ng/mmol creatinine,P<0.01}. 5. In severe exacerbation of COPD, the level of Isoprostane F2а-Ⅲin urine inverse relationship with partial pressure of oxygen(r= 0.442 , p=0.040), and positive relationship with partial pressure of carbon dioxide(r=0.658 , p=0.001).Conclusions: 1. In severe exacerbation of COPD, the level of Isoprostane F2а-Ⅲwas significantly higher than stable stage of COPD. This indicates that the system oxidative stress was greatly increased in evere exacerbation of COPD. 2. In COPD severe exacerbation and stable stage patients, the level of Isoprostane F2а-Ⅲwas significantly higher than healthy non-smokers These indicate that it has higher the level of oxidative stress in COPD, and oxidative stress may play an important role in the pathogenesis of COPD. 3. In COPD severe exacerbation and stable stage patients, the level of Isoprostane F2а-Ⅲwere not significantly different from the healthy smokers.These indicate that cigarette smoking is a important risk factor in COPD, but not everyone smoker will to becom COPD patients. 4. The level of Isoprostane F2а-Ⅲin healthy smokers was significantly higher than healthy non-smokers. This indicates that cigarette smoking can increase the level of oxidants, which may induce and enhance oxidative stress. 5. In severe exacerbation of COPD, the level of Isoprostane F2а-Ⅲin urine inverse relationship with partial pressure of oxygen and positive relationship with partial pressure of carbon dioxide. These indicate that partial pressure of oxygen and partial pressure of carbon dioxide may effect the level of oxidative stress in COPD severe exacerbation.