Effects of moderate altitude on exhaled nitric oxide, erythrocytes lipid peroxidation and superoxide dismutase levels

The purpose of this study was to investigate the effects of staying at a mo derate altitude (2,300 m, 7 d) on the levels of plasma nitrite, exhaled nit ric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD), Measu rements were obtained from 9 female (mean age 18.3+/-2) and 9 male (mean ag e 19.3+/-3.7) cross-country volunteer skiers: before, during (Ist day, 7th day) and after staying at a moderate altitude. Exhaled nitric oxide levels were measured only before and after staying at the altitude, Nitrite levels increased throughout the stay at the altitude, while MDA levels decreased. In parallel with the nitrite levels, SOD activities were also found to hav e increased. Exhaled NO values were decreased after the stay at the moderat e altitude, These results show that altitude hypoxia causes decreased in NO levels in the lung but increased systemic NO levels in the blood due to in hibition of erythrocyte lipid peroxidation.