title: Colonoscopy in mice.
abstract: BACKGROUND
  Current investigational models of murine colitis and colon cancer necessitate sacrifice of animals in order to obtain colonic tissue. The purpose of this study was to develop a safe method of murine colonoscopy that would allow serial evaluation and mucosal biopsies of the same animal.
  
  
  METHODS
  Nine mice (two C3H, two C57/BL6, and five IL-10 deficient) were studied a total of four times each over 4 weeks. Three mice [APC (Min +/-)] were examined three times each. Mice were gavaged with 1 cc of a polyethylene glycol solution on the day prior to colonoscopy. Solid chow was withheld and the mice were maintained on Pedialyte. Mice were anesthetized with ketamine and xylazine. A flexible pediatric cystoscope (2.1-mm diameter) with a single biopsy channel was introduced per anum, and the colon was gently insufflated with air to a mean pressure of less than 5 mmHg. Saline irrigation was used when necessary. A single biopsy was obtained from the rectosigmoid colon during each examination.
  
  
  RESULTS
  A total of 46 examinations were carried out. One mouse died after being anesthesized for the fourth examination, and two mice [one IL-10 knockout and one APC (Min+/-)] died one day after the 3rd examination. No other complications were noted. The average length of insertion was 3 cm. Transillumination allowed for localization of the endoscope tip. Biopsies, although quite small, were sufficient for pathologic evaluation and diagnosis.
  
  
  CONCLUSIONS
  Murine colonoscopy is a safe and feasible technique. It permits consecutive visual and histopathological examinations, and it allows the investigator to monitor the response of the murine colon to experimental interventions.
authors.affiliation: Department of Surgery, College of Physicians and Surgeons, Columbia University, 161 Fort Washington Avenue, New York, NY 10032, USA. eh257@columbia.edu
authors.forename: E H
authors.initials: EH
authors.lastname: Huang
authors.forename: J J
authors.initials: JJ
authors.lastname: Carter
authors.forename: R L
authors.initials: RL
authors.lastname: Whelan
authors.forename: Y H
authors.initials: YH
authors.lastname: Liu
authors.forename: J O
authors.initials: JO
authors.lastname: Rosenberg
authors.forename: H
authors.initials: H
authors.lastname: Rotterdam
authors.forename: A M
authors.initials: AM
authors.lastname: Schmidt
authors.forename: D M
authors.initials: DM
authors.lastname: Stern
authors.forename: K A
authors.initials: KA
authors.lastname: Forde
mesh_terms: D000818:Animals; D001706:Biopsy / Q000295:instrumentation / Q000379:methods; D003092:Colitis / Q000473:pathology*; D003110:Colonic Neoplasms / Q000473:pathology*; D003113:Colonoscopy / Q000379:methods*; D004195:Disease Models, Animal; D007413:Intestinal Mucosa / Q000473:pathology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008817:Mice, Mutant Strains