title: Amelioration of intestinal ischemia-reperfusion injury with intraluminal hyperoxygenated solution: studies on structural and functional changes of enterocyte mitochondria.
abstract: BACKGROUND
  The aim of this study was to investigate the effects of intraluminal hyperoxygenated solution (HOS) on enterocyte mitochondrial structure and respiratory function after intestinal ischemia-reperfusion (IR) in rabbits.
  
  
  METHODS
  Thirty-two rabbits were divided randomly into four groups: control group in which sham operation was performed (Sham group), ischemia-reperfusion group (IR group), and two HOS treatment groups (H1 group and H2 group). Intestinal IR model was produced by clamping superior mesenteric artery (SMA) with an atraumatic vascular clamp for 1 h, followed by reperfusion for 2 h. Animals in the H1 group and H2 group received intraluminal HOS infusion for 1 h immediately after occlusion of SMA, and the rates of infusion were 10 and 20 mL/kg.h, respectively. After 2 h of reperfusion, enterocyte mitochondria morphological quantitative analysis was made with electron microscopy and biogenetics stereology, and the following parameters, including mitochondrial respiratory control ratio (RCR), intestinal O(2) extraction ratio (ER), and mucosal ATP contents, were measured, respectively.
  
  
  RESULTS
  After IR, the mitochondria was severely swollen with broken cristae, and mean transaction area, diameter, surface density, and volume density of the mitochondria increased significantly. Meanwhile, specific surface and numeral density of the mitochondria decreased significantly. The mitochondrial RCR, intestinal O(2) ER, and mucosal ATP contents were all decreased significantly. There were no differences in all parameters between the IR group and H1 group. In the H2 group, the mitochondria were slightly swollen, and mean transaction area, diameter, surface density, and volume density of the mitochondria were all significantly lower, with the specific surface and numeral density of the mitochondria significantly higher compared with the IR group. The mitochondrial RCR, intestinal O(2) ER and mucosal ATP contents in H2 group were all significantly higher than those in IR group.
  
  
  CONCLUSIONS
  Intraluminal HOS infusion at 20 mL/kg.h during ischemia ameliorates structural and functional changes of enterocyte mitochondria associated with intestinal IR injury, which is a safe, simple, and effective measure to protect the intestine from IR injury.
authors.affiliation: Department of Anesthesiology, Stomatology Hospital, Fourth Military Medical University, Xi' an, Shaanxi Province, China.
authors.forename: Changjun
authors.initials: C
authors.lastname: Gao
authors.forename: Lixian
authors.initials: L
authors.lastname: Xu
authors.forename: Wei
authors.initials: W
authors.lastname: Chai
authors.forename: Xude
authors.initials: X
authors.lastname: Sun
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Guihe
authors.initials: G
authors.lastname: Zhang
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D020895:Enterocytes / Q000378:metabolism* / Q000473:pathology; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000473:pathology; D007422:Intestines / Q000473:pathology; D008297:Male; D008854:Microscopy, Electron; D008928:Mitochondria / Q000378:metabolism* / Q000648:ultrastructure; D010100:Oxygen / Q000494:pharmacology*; D010477:Perfusion; D011817:Rabbits; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D012996:Solutions / Q000494:pharmacology
chemical_list: D012996:Solutions; D000255:Adenosine Triphosphate; D010100:Oxygen