title: [The effect of hydrogen on hemorrhagic shock induced acute lung injury in rats].
abstract: OBJECTIVE
  To investigate the effect of hydrogen inhalation on acute lung injury after hemorrhagic shock in rats.
  
  
  METHODS
  Twenty-four adult male Sprague-Dawley (SD) rats were equally randomized into three groups: sham operation group, model group and hydrogen-treatment group. Pressure-controlled hemorrhagic shock and resuscitation model was reproduced by blood-letting for 1 hour followed by fluid replacement for 2 hours. The rats in model group received a mixture of 50% oxygen-50% nitrogen during the process. The rats in hydrogen-treatment group received inhalation of a mixture of 2% hydrogen-48% nitrogen-50% oxygen 10 minutes before fluid replacement till the end of resuscitation. The arterial blood samples were collected for the measurement of arterial partial pressure of oxygen (PaO₂) before exsanguination, 1 hour after shock, 1 hour and 2 hours after fluid replacement. Blood and lung tissues were collected at the end of experiment, and tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels in plasma, lung wet/dry weight ratio (W/D), malondialdehyde (MDA) content, superoxide dismutase (SOD) and myeloperoxidase (MPO) activity in the lung tissue were determined. The lung tissue was subjected to pathological examination.
  
  
  RESULTS
  At the end of fluid replacement, compared with model group, hydrogen could significantly reduce pulmonary edema (lung W/D ratio: 4.72 ± 0.12 vs. 4.94 ± 0.14, P<0.05), inhibit oxidative stress (MDA: 0.55 ± 0.09 nmol/mg vs. 0.72 ± 0.08 nmol/mg, P<0.05), enhance antioxidant activity (SOD activity: 79.53 ± 14.33 U/mg vs. 59.55 ± 9.07 U/mg, P<0.05), reduce the release of pro-inflammatory cytokines (TNF-α: 55.58 ± 10.06 ng/L vs. 66.58 ± 5.17 ng/L; IL-6: 23.00 ± 2.77 ng/L vs. 27.09 ± 2.46 ng/L, both P<0.05) and inhibit neutrophil infiltration (MPO: 1.05 ± 0.18 U/g vs. 1.40 ± 0.14 U/g, P<0.05). It alleviated the damage to lung tissue, and then improved the lung function (PaO₂: 146.3 ± 22.1 mm Hg vs. 123.6 ± 16.0 mm Hg, P<0.05).
  
  
  CONCLUSIONS
  Hydrogen treatment can alleviate acute lung injury as a result of hemorrhagic shock and resuscitation.
authors.affiliation: Department of Pain, the Second Affiliated Hospital of Harbin Medical University, Heilongjiang Provincial Key Lab of Research on Anesthesiology and Critical Care Medicine, China.
authors.forename: Hai-mei
authors.initials: HM
authors.lastname: Shi
authors.forename: Hua-cheng
authors.initials: HC
authors.lastname: Zhou
authors.forename: Ya-rui
authors.initials: YR
authors.lastname: Jia
authors.forename: Ya
authors.initials: Y
authors.lastname: Wang
authors.forename: Jin-feng
authors.initials: JF
authors.lastname: Liu
mesh_terms: D055371:Acute Lung Injury / Q000188:drug therapy* / Q000209:etiology*; D000818:Animals; D004195:Disease Models, Animal; D006859:Hydrogen / Q000627:therapeutic use*; D015850:Interleukin-6 / Q000097:blood; D008168:Lung / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012771:Shock, Hemorrhagic / Q000150:complications*; D013482:Superoxide Dismutase / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D008315:Malondialdehyde; D006859:Hydrogen; D009195:Peroxidase; D013482:Superoxide Dismutase