title: Novel isolated cecal pouch model for endoscopic observation in rats.
abstract: OBJECTIVE
  To create a new rat model for drug administration, cell transplantation, and endoscopic examination for the treatment of intestinal diseases.
  
  
  METHODS
  F344/NJc l-rnu/rnu rats (10-wk-old males, 350-400 g) were used in this study. The rats were anesthetized via 2% isoflurane inhalation. The rat's cecum was isolated from the intestines, and a pouch was created. The remainder of the intestines was rejoined to create an anastomosis. The "side-to-side" anastomosis (SSA) technique initially involves the creation of a 2-cm longitudinal incision into each intestinal wall. To create an anastomosis along the ileal and colonic walls, both intestines were cut, and a continuous suture procedure was performed that included all layers of both intestines. The serous membrane was sutured along the edge and on the anterior wall of the anastomosis. The "end-to-end" anastomosis (EEA) technique was compared with the SSA technique. In the EEA technique, the frontal surfaces of both cut intestinal lumens were joined together by continuous sutures. Additional sutures were made at the serosa. After the anastomotic intestine was successfully constructed, the two intestinal lumens that were cut at the isolated cecum were managed. In addition, one luminal side of the pouch remained open to create an artificial anus on the dorsum as a passage for the residual substances in the pouch. Finally, small animal endoscopy was used to observe the inside of the pouch.
  
  
  RESULTS
  In this animal model, mucus and feces are excreted through the reconstructed passage. Accordingly, the cecal pouch mucosa was not obstructed or contaminated by feces, thus facilitating observations of the luminal surface of the intestine. The endoscopic observation of the cecal pouch provided clear visualization given the absence of feces. The membrane surface of the cecum was clearly observed. Two methods of creating an anastomotic intestine, the "SSA" and "EEA" techniques, were compared with regard to animal survival rate, complication rate, and operation time. The SSA technique resulted in a significantly increased survival rate and a lower incidence of complications in rat models compared with the EEA technique. The complications of stenosis and leakage resulted in death in the EEA technique. Thus, the EEA technique exhibited a lower survival rate compared with the SSA technique. However, the SSA technique required a significantly longer operation time compared with the EEA technique.
  
  
  CONCLUSIONS
  Our new rat model is potentially useful for the development of a novel treatment for intestinal diseases.
authors.affiliation: Kurodo Koshino, Nobuo Kanai, Masakazu Yamamoto, Institute of Gastroenterology, School of Surgery, Tokyo Women's Medical University, Shinjuku-ku, Tokyo 162-8666, Japan.
authors.forename: Kurodo
authors.initials: K
authors.lastname: Koshino
authors.affiliation: Kurodo Koshino, Nobuo Kanai, Masakazu Yamamoto, Institute of Gastroenterology, School of Surgery, Tokyo Women's Medical University, Shinjuku-ku, Tokyo 162-8666, Japan.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Kanai
authors.affiliation: Kurodo Koshino, Nobuo Kanai, Masakazu Yamamoto, Institute of Gastroenterology, School of Surgery, Tokyo Women's Medical University, Shinjuku-ku, Tokyo 162-8666, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yamato
authors.affiliation: Kurodo Koshino, Nobuo Kanai, Masakazu Yamamoto, Institute of Gastroenterology, School of Surgery, Tokyo Women's Medical University, Shinjuku-ku, Tokyo 162-8666, Japan.
authors.forename: Teruo
authors.initials: T
authors.lastname: Okano
authors.affiliation: Kurodo Koshino, Nobuo Kanai, Masakazu Yamamoto, Institute of Gastroenterology, School of Surgery, Tokyo Women's Medical University, Shinjuku-ku, Tokyo 162-8666, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yamamoto
mesh_terms: D000714:Anastomosis, Surgical; D057868:Anastomotic Leak / Q000209:etiology / Q000473:pathology; D000818:Animals; D002432:Cecum / Q000473:pathology / Q000601:surgery*; D002478:Cells, Cultured; D003106:Colon / Q000601:surgery; D003672:Defecation; D016099:Endoscopy, Gastrointestinal; D004847:Epithelial Cells / Q000637:transplantation; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D007082:Ileum / Q000601:surgery; D007413:Intestinal Mucosa / Q000473:pathology / Q000601:surgery*; D007415:Intestinal Obstruction / Q000209:etiology / Q000473:pathology; D008297:Male; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D023421:Models, Animal; D011916:Rats, Inbred F344; D011923:Rats, Nude; D019738:Surgically-Created Structures / Q000009:adverse effects; D013536:Suture Techniques; D014456:Ulcer / Q000473:pathology
chemical_list: C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins
keywords: Anastomosis; Animal model; Cecal pouch; Endoscopy; Microsurgery