title: Inflammatory alterations in excluded colon in rats: a comparison with chemically induced colitis.
abstract: Diversion colitis occurs commonly in the large bowel remnant after diversion of the fecal stream. Several experimental models of colitis have been described, but none examine the inflammatory alterations that can occur in experimentally defunctioned colons. This characterization could be useful in understanding pathophysiological aspects of diversion colitis, and in developing future therapeutic strategies. Thus, we evaluated the temporal inflammatory alterations in the defunctioned colon of rats by analyzing the histological results, infiltrating neutrophils, pro-inflammatory markers such as cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS), and DNA damage in isolated colonocytes. We compared the obtained data with those from hapten-induced colitis. The experimental diversion of the colon fecal stream induces diversion colitis characterized by an early inflammatory process with increased neutrophil infiltrate, and COX-2 and iNOS expression that resembles, in some aspects, the inflammatory characteristics of chemically induced colitis. After acute inflammation resolution, there was an increase in COX-2 and iNOS expression and the presence of lymphoid follicular hyperplasia and ulcerations, suggesting that diversion colitis can be experimentally established and useful for studying different pathophysiological aspects of this condition.
authors.affiliation: Clinical Pharmacology and Gastroenterology Unit, São Francisco University Medical School, Bragança Paulista, São Paulo, Brazil.
authors.forename: Thamara Sigrist
authors.initials: TS
authors.lastname: Longatti
authors.forename: Simone Coghetto
authors.initials: SC
authors.lastname: Acedo
authors.forename: Caroline Candida
authors.initials: CC
authors.lastname: de Oliveira
authors.forename: Daniel Duarte da Conceição
authors.initials: DD
authors.lastname: Miranda
authors.forename: Denise Gonçalves
authors.initials: DG
authors.lastname: Priolli
authors.forename: Marcelo Lima
authors.initials: ML
authors.lastname: Ribeiro
authors.forename: Alessandra
authors.initials: A
authors.lastname: Gambero
authors.forename: Carlos Augusto Real
authors.initials: CA
authors.lastname: Martinez
mesh_terms: D000818:Animals; D003092:Colitis / Q000139:chemically induced / Q000473:pathology* / Q000503:physiopathology*; D051546:Cyclooxygenase 2 / Q000378:metabolism; D004195:Disease Models, Animal; D007249:Inflammation / Q000503:physiopathology*; D008297:Male; D019001:Nitric Oxide Synthase / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D019001:Nitric Oxide Synthase; D051546:Cyclooxygenase 2