Role of hyperbaric oxygen exposure in reduction of lipid peroxidation and in multiple organ failure induced by zymosan administration in the rat

The aim of the present study was to evaluate the effects of hyperbaric oxyg en (HBO) therapy on multiple organ failure induced by zymosan. Administrati on of zymosan (500 mg/kg) in the rat induced neutrophil infiltration in the lung, liver, and intestine as evaluated by increase in myeloperoxidase (MP O) activity. Therefore, lipid peroxidation was significantly increased in z ymosan-treated rats. This inflammatory process coincided with the damage of lung, liver, and small intestine. Immunohistochemical examination demonstr ated a marked increase in the immunoreactivity to nitrotyrosine in the lung , liver, and small intestine of zymosan-shocked rats. HBO (2 absolute Atmos phere) exposure attenuates the increase in the tissue levels of MPO and mal ondialdehyde (MDA) caused by zymosan in the lung, liver, and intestine. In addition, HBO (2 absolute Atmosphere) was effective in preventing the devel opment of lung, liver, and intestine injury. Taken together, the present re sults demonstrate that HBO may also be an efficacious treatment in multiple organ failure induced by zymosan.