CONTEXT: Despite its known benefits, hyperbaric @entity26 (HBO) is also reported to enhance the production of reactive @entity26 species and can cause oxidative stress in several tissues. Previous studies had shown that HBO-induced oxidative stress is directly proportional to both its exposure pressure and duration. Nevertheless, these studies were usually performed with single-session HBO exposure but its clinical use commonly depends on long-term exposure periods. OBJECTIVE: To clarify the oxidative effect of long-term repetitive HBO in the lung tissue of @entity35 . MATERIALS AND METHODS: Male @entity35 were divided into six study groups exposed to consecutive HBO sessions (2.8 atm/90    min) for 5, 10, 15, 20, 30, and 40 days. Animals were sacrificed 24    h after the last HBO session. An additional control group was set to obtain normal data. Lung @entity1234 ( @entity1865 ) and carbonylated protein (PCC) levels were determined as measures of oxidative stress along with the activities of the antioxidant enzymes @entity224 dismutase (SOD) and @entity2041 peroxidase. RESULTS: None of the measured parameters showed any changes among the groups exposed to 5-15 HBO sessions. However, @entity1865 , PCC, and SOD were found to be significantly increased in the 20 to 40 session groups. DISCUSSION AND CONCLUSION: These results indicate that repetitive treatment with HBO may cause oxidative stress in critical tissues including the lung. Although HBO-mediated free radicals are accepted to be responsible for the benefits of this therapeutic modality, especially in cases with prolonged exposure, possible injurious effects of supranormal values of bio-oxidative products need to be considered.

Long-term exposure to repetitive hyperbaric XXXX results in cumulative oxidative stress in @entity35 lung tissue.

@entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity2041 :: ('MESH:D005978', 'Chemical') :: ['glutathione'] @entity1234 :: ('MESH:D008315', 'Chemical') :: ['malondialdehyde'] @entity35 :: ('10116', 'Species') :: ['Sprague-Dawley rats', 'rats'] @entity224 :: ('MESH:D013481', 'Chemical') :: ['superoxide'] @entity1865 :: ('CHEBI:566274', 'Chemical') :: ['MDA']
@entity26 :: (MESH:D010100,Chemical) :: ['oxygen']
