title: Effects of hydrogen peroxide scavenger Catalase on villous microcirculation in the rat small intestine in a model of inflammatory bowel disease.
abstract: This study was conducted to quantify the effect of systemic Catalase, a hydrogen peroxide scavenger, on villous microcirculation in the inflamed small intestine of the rat. Intestinal inflammation was induced with s.c. application of Indomethacin. Intravital fluorescence microscopy and FITC-labeled erythrocytes were used to quantify erythrocyte velocity and arteriolar diameter in the main arteriole of the villi in the terminal ileum following i.v. application of Catalase in the inflamed intestine, and the blood flow was calculated. Control groups were formed for Ringer's lactate, Catalase and Indomethacin, respectively. We found that villous blood flow was significantly increased in the in the inflamed intestine. Application of Catalase led to a significant decrease in villous perfusion, but had no effect in the control group. The increase in villous blood flow was accompanied by changes in the diameter of the main arteriole. This effect on arteriolar diameter was reversed by i.v. Catalase. Our results provide evidence that systemic application of Indomethacin leads to vasodilatation of the main arteriole of the villus in the rat ileum and hyperemia in the mucosa. Hyperemia and the vascular diameter of the main arteriole were significantly reduced by H(2)O(2)-scavenger Catalase, suggesting that endogenous H(2)O(2) may be one of the mediators of hyperemia in the mucosa in this animal model of intestinal inflammation.
authors.affiliation: Department of Surgery, Department of Pathology, Technische Universität München, Klinikum rechts der Isar, Ismaninger Strasse 22, Munich, 81675, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Ruh
authors.forename: F
authors.initials: F
authors.lastname: Vogel
authors.forename: E
authors.initials: E
authors.lastname: Schmidt
authors.forename: M
authors.initials: M
authors.lastname: Werner
authors.forename: E
authors.initials: E
authors.lastname: Klar
authors.forename: A
authors.initials: A
authors.lastname: Secchi
authors.forename: M M
authors.initials: MM
authors.lastname: Gebhard
authors.forename: F
authors.initials: F
authors.lastname: Glaser
authors.forename: C
authors.initials: C
authors.lastname: Herfarth
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D002374:Catalase / Q000494:pharmacology*; D016861:Cyclooxygenase Inhibitors / Q000633:toxicity; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D016166:Free Radical Scavengers / Q000494:pharmacology*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D006940:Hyperemia / Q000139:chemically induced; D007082:Ileum / Q000098:blood supply* / Q000648:ultrastructure; D007213:Indomethacin / Q000633:toxicity; D015212:Inflammatory Bowel Diseases / Q000139:chemically induced / Q000188:drug therapy*; D007413:Intestinal Mucosa / Q000187:drug effects; D007552:Isotonic Solutions / Q000633:toxicity; D008297:Male; D008833:Microcirculation / Q000187:drug effects*; D008871:Microvilli / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012119:Respiration / Q000187:drug effects; D000077325:Ringer's Lactate
chemical_list: D016861:Cyclooxygenase Inhibitors; D016166:Free Radical Scavengers; D007552:Isotonic Solutions; D000077325:Ringer's Lactate; D006861:Hydrogen Peroxide; D002374:Catalase; D007213:Indomethacin