Protective effects of hydrogen gas on acute lung injury induced by smoke inhalation in rats and its doseeffect relationship

Objective:To discuss the therapeutical effect on smoke inhalation injury in rats under different doses of hydrogen-rich saline.Methods:Thirty rats were randomly divided into 5 groups:control group(C),inhalation group(I),low dose group(2.5 mL/kg,HSL),medium dose group(5 mL/kg,HSM),and high dose group(10 mL/kg,HSH).At 24 hours after injured,all rats were sacrificed and specimens were taken.The histopathological changes of lung tissue were observed using electron micrography.Tumor necrosis factor-α(TNF-α) in plasma was quantified,malondialdehyde(MDA) content of lung tissue was also detected,the NF-κBp65 in lung speciments was examined by immunohistochemistry technology,and the apoptosis of lung was monitored by terminal deoxynucleotidyl transfercase dUTP nik end labeling(TUNEL) assay.Results:When a comparison was made with the inhalation group,hydrogen-rich saline treatment could significantly relieve acute lung injury induced by inhalation injury as indicated by ultrastructural histopathologic changes under electron micrography and decrease TNF-α level.Furthermore,hydrogen-rich saline could inhibit lipid oxidation(MDA level was significantly decreased),the expression of NF-κBp65 and apoptosis of lung tissue,especially in medium and high dose group,while this change was not significant in low dose group.Conclusion:Hydrogen-rich saline treatment could significantly relieve acute lung injury induced by inhalation injury,with dose-effect relationship.