Protective effects of melatonin on lung damage associated with one-lung ventilation: An experimental study

This study aims to investigate the protective effect of melatonin on lung damage induced by one-lung ventilation in a rat model. A total of 20 healthy, Sprague-Dawley male rats were randomized into two equal groups as control (n=10) and melatonin groups (n=10). The control group underwent 60 min of one-lung ventilation, followed by 30 min of two-lung ventilation. In the melatonin group, the rats were administered 10 mg/kg melatonin intraperitoneally 10 min before the start of the experiment. At the end of both ventilation periods, tissue samples were obtained from the lungs of the control and melatonin groups for biochemical analysis and histopathological examinations. Tissue superoxide dismutase, malondialdehyde, and tumor necrosis factor-alpha levels were measured. Lung tissue samples were examined based on the presence and amount of alveolar congestion, intra-alveolar bleeding, and leukocyte and lymphocyte infiltration. At the end of the study, lung tissue malondialdehyde (3.8±0.9 vs. 1.8±0.8 μM; p