title: Effects of mechanical ventilation with different tidal volume on oxidative stress and antioxidant in lung.
abstract: OBJECTIVE
  The aim of this study was to investigate the changes in oxidative stress and antioxidants in lung tissue under different tidal volume ventilation conditions.
  
  
  METHODS
  Forty-eight male Wistar rats were randomized into four groups, namely, group C, the control group, which was not ventilated, and groups C1, C2 and C3, the treatment groups, which were ventilated for 2 h with tidal volumes of 8, 30 and 42 ml/kg, respectively. The right middle lobe was assayed for malondialdehyde (MDA), the right posterior lobe was assayed using Western blotting for Nrf2, GCLm and SrX1 and the left lobe was assayed for Nrf2, GCLm and SrX1 mRNA.
  
  
  RESULTS
  The MDA levels were increased in the three treatment groups, with MDA levels highest in group C3 and lowest in group C1 (C3 > C2 > C1) (all P < 0.05). The mRNA expression of Nrf2, GCLm and SrX1 was highest in group C3 and lowest in group 1 (C3 > C2 > C1) (all P < 0.05). No significant difference was observed between group C1 and group C (P > 0.05). A Western blot analysis showed that Nrf2, GCLm and SrX1 expression was highest in group C3 and lowest in group C1 (C3 > C2 > C1) (all P < 0.05). No significant difference was observed between group C1 and group C (P > 0.05).
  
  
  CONCLUSIONS
  Oxidative stress and antioxidant enzyme levels in the lungs of rats were positively associated with the tidal volumes of mechanical ventilation, suggesting that higher tidal volumes cause more severe oxidative stress and increased antioxidant responses.
authors.affiliation: Department of Anesthesia, The First Affiliated Hospital of Zhengzhou University, No. 1, Jianshe dong Road, Zhengzhou, Henan, China. gentlesun@126.com.
authors.forename: Zhen-Tao
authors.initials: ZT
authors.lastname: Sun
authors.affiliation: Department of Anesthesia, Henan Cancer Hospital, Zhengzhou, Henan, China.
authors.forename: Chun-Yao
authors.initials: CY
authors.lastname: Yang
authors.affiliation: Department of Respiratory Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Miao
authors.affiliation: Molecular Key Laboratory of Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Shan-Feng
authors.initials: SF
authors.lastname: Zhang
authors.affiliation: Department of Anesthesia, The First Affiliated Hospital of Zhengzhou University, No. 1, Jianshe dong Road, Zhengzhou, Henan, China.
authors.forename: Xue-Ping
authors.initials: XP
authors.lastname: Han
authors.affiliation: Department of Anesthesia, The First Affiliated Hospital of Zhengzhou University, No. 1, Jianshe dong Road, Zhengzhou, Henan, China.
authors.forename: Su-En
authors.initials: SE
authors.lastname: Ren
authors.affiliation: Department of Anesthesia, The First Affiliated Hospital of Zhengzhou University, No. 1, Jianshe dong Road, Zhengzhou, Henan, China.
authors.forename: Xue-Qing
authors.initials: XQ
authors.lastname: Sun
authors.affiliation: Department of Anesthesia, The First Affiliated Hospital of Zhengzhou University, No. 1, Jianshe dong Road, Zhengzhou, Henan, China.
authors.forename: Ya-Nan
authors.initials: YN
authors.lastname: Cao
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D008168:Lung / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012121:Respiration, Artificial / Q000379:methods*; D013990:Tidal Volume / Q000502:physiology
chemical_list: D000975:Antioxidants; D008315:Malondialdehyde