title: Can chronic intra-abdominal hypertension cause oxidative stress to the abdominal wall muscles? An experimental study.
abstract: BACKGROUND
  The aim of this study was to test the hypothesis that intra-abdominal hypertension alone could trigger such changes to the rectus abdominis muscle that would lead to an imbalance between oxidant production and antioxidant protection.
  
  
  METHODS
  Forty-five New Zealand white rabbits were divided into three groups and a rubber bag was implanted into their peritoneal cavity. In group A (n = 15), the bag was empty. In group B (n = 15), it was filled with normal saline to achieve an intra-abdominal pressure of over 12 mm Hg. In group C (n = 15), it was filled with lead equiponderant to the mean weight of the normal saline injected in group B. After 8 weeks, we measured in rectus abdominis muscle biopsies the lipid peroxidation products, the protein carbonyl content, the total glutathione and superoxide dismutase (SOD) concentration, the activity of glutathione reductase and glutathione peroxidase, and the pro-oxidant-antioxidant balance.
  
  
  RESULTS
  The lipid peroxidation products were significantly higher in group B compared with both group A (P = 0.026) and group C (P < 0.001). The total protein carbonyl content was significantly higher in group B compared with both group A (P = 0.006) and group C (P < 0.001). No difference was found between the three groups in total glutathione (P = 0.735) and SOD (P = 0.410) concentration. Glutathione peroxidase activity was higher in groups B and C compared with group A (P = 0.05 and P = 0.003, respectively). Glutathione reductase activity was higher in group B compared with group A (P = 0.005) and group C (P = 0.001). The pro-oxidant antioxidant balance was higher in group B compared with the group A (P = 0.012).
  
  
  CONCLUSIONS
  Maintaining the IP over 12 mm Hg for 8 wk caused increased oxidative damage to both lipids and proteins with an increased pro-oxidant-antioxidant balance. In an attempt to compensate for this damage the muscle fibers increased their glutathione reductase and glutathione peroxidase activity.
authors: AHEPA Hospital, C' Department of Surgery, Aristotle University of Thessaloniki, Thessaloniki, Greece. skotidis@med.auth.gr
authors: Efstathios
authors: E
authors: Kotidis
authors: Theodosis
authors: T
authors: Papavramidis
authors: Konstantinos
authors: K
authors: Ioannidis
authors: George
authors: G
authors: Koliakos
authors: Thomai
authors: T
authors: Lazou
authors: Aggeliki
authors: A
authors: Cheva
authors: Nikolaos
authors: N
authors: Michalopoulos
authors: Spiros
authors: S
authors: Papavramidis
mesh_terms: D000009:Abdominal Muscles / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D034861:Abdominal Wall / Q000503:physiopathology*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001706:Biopsy; D002908:Chronic Disease; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D059325:Intra-Abdominal Hypertension / Q000150:complications* / Q000503:physiopathology*; D015227:Lipid Peroxidation / Q000502:physiology; D008297:Male; D023421:Models, Animal; D018384:Oxidative Stress / Q000502:physiology*; D011817:Rabbits; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005978:Glutathione