title: Role of oxidative stress in animal model of visceral pain.
abstract: Reactive oxygen species play an important role both in physiological and pathophysiological reactions. The aim of this study was to determine the role of free radicals and antioxidants in the development of visceral pain. Visceral pain was produced by colorectal distension (CRD) in adult rats. CRD was caused by insertion of a lubricated latex balloon into the descending colon and rectum followed by inflation to 80mm Hg for 10min. During CRD, visceral pain was rated on 0-3.5 point scale. Oxidative stress was determined indirectly by measurement of free radical scavenging enzymes (glutathione peroxidase (GPx) and superoxide dismutase (SOD)) in the blood, liver and brain. Following CRD we observed (1) all rats expressed signs of visceral pain (overall rating was 1.83), (2) SOD and GPx levels were increased in the liver and blood, and decreased in the brain samples and (3) administration of the antioxidant Trolox, a water-soluble derivate of vitamin E, prior to CRD, prevented SOD and GPx changes in the liver, blood and brain, but did not affect pain scores. It was concluded, that CRD as a model of visceral pain, increases oxidative stress in animals, which could be prevented by prior administration of antioxidants; however, antioxidants did not attenuate signs of visceral pain caused by CRD.
authors.affiliation: Third Faculty of Medicine, Charles University in Prague, Dpt. of Normal, Pathological and Clinical Physiology, Czech Republic. svaculin@lf3.cuni.cz
authors.forename: Simon
authors.initials: S
authors.lastname: Vaculin
authors.forename: Miloslav
authors.initials: M
authors.lastname: Franek
authors.forename: Martin
authors.initials: M
authors.lastname: Vejrazka
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001921:Brain / Q000201:enzymology; D002839:Chromans / Q000494:pharmacology; D003106:Colon / Q000473:pathology; D004108:Dilatation, Pathologic / Q000150:complications; D005979:Glutathione Peroxidase / Q000097:blood / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D008297:Male; D018384:Oxidative Stress; D010146:Pain / Q000209:etiology / Q000378:metabolism* / Q000517:prevention & control; D010147:Pain Measurement; D051381:Rats; D012007:Rectum / Q000473:pathology; D013314:Stress, Mechanical; D013482:Superoxide Dismutase / Q000097:blood / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002839:Chromans; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid