BACKGROUND: Hydrogen gas, an antioxidant agent, was found to protect against cerebral and myocardial ischemia-reperfusion (I/R) injury. In the present study, we investigated the effect of hydrogen-rich saline (HRS) on the I/R-induced lung injury. METHODS: Left lung of male New Zealand White rabbits rendered normothermic ischemia for 60 min and reperfused for up to 240 min. Treated animals received intraperitoneal injection of 5 mL/kg HRS or the same volume of normal saline 10 min before the start of reperfusion. Blood and lung tissue samples were obtained for blood gas and biochemical analyses. The tissues obtained from lower lobe of left lung were used for histologic examination. RESULTS: After 240 min of reperfusion, intraperitoneal administration of HRS increased PaO2/FiO2 ratio and superoxide dismutase activities, and decreased malondialdehyde contents, proinflammatory cytokines expression, and myeloperoxidase activities, along with reduced wet/dry ratio and histologic injury scores (P < 0.05 versus I/R group). CONCLUSIONS: These results suggest that intraperitoneal administration of HRS before reperfusion protects the lung from I/R injury. The protective effect seems to be closely related to regulating oxidative damage and antioxidant enzyme activities and neutrophil infiltration.
BACKGROUND:Hydrogen gas, an antioxidant agent, was found to protect against cerebral and myocardial ischemia-reperfusion (I/R) injury. In the present study, we investigated the effect of hydrogen-rich saline (HRS) on the I/R-induced lung injury. METHODS: Left lung of male New Zealand White rabbits rendered normothermic ischemia for 60 min and reperfused for up to 240 min. Treated animals received intraperitoneal injection of 5 mL/kg HRS or the same volume of normal saline 10 min before the start of reperfusion. Blood and lung tissue samples were obtained for blood gas and biochemical analyses. The tissues obtained from lower lobe of left lung were used for histologic examination. RESULTS: After 240 min of reperfusion, intraperitoneal administration of HRS increased PaO2/FiO2 ratio and superoxide dismutase activities, and decreased malondialdehyde contents, proinflammatory cytokines expression, and myeloperoxidase activities, along with reduced wet/dry ratio and histologic injury scores (P < 0.05 versus I/R group). CONCLUSIONS: These results suggest that intraperitoneal administration of HRS before reperfusion protects the lung from I/R injury. The protective effect seems to be closely related to regulating oxidative damage and antioxidant enzyme activities and neutrophil infiltration.