title: A neurokinin 1 receptor antagonist reduces an ongoing ileal pouch inflammation and the response to a subsequent inflammatory stimulus.
abstract: Ileal pouch-anal anastomosis (IPAA) is an excellent surgical option for patients with chronic ulcerative colitis (CUC) requiring colectomy; however, persistent episodes of ileal pouch inflammation, or pouchitis, may result in debilitating postoperative complications. Because considerable evidence implicates substance P (SP) as an inflammatory mediator of CUC, we investigated whether SP participates in the pathophysiology of pouchitis. With the use of a rat model of IPAA that we developed, we showed that ileal pouch MPO levels and neurokinin 1 receptor (NK-1R) protein expression by Western blot analysis were significantly elevated 28 days after IPAA surgery. In situ hybridization and immunohistochemistry showed that the increase in NK-1R protein expression was localized to the lamina propria and epithelia of pouch ileum. The intraperitoneal administration of the NK-1R antagonist (NK-1RA) CJ-12,255 for 4 days, starting on day 28, was effective in reducing MPO levels. Starting on day 28, animals with IPAA were given 5% dextran sulfate sodium (DSS) in their drinking water for 4 days, which caused histological and physical signs of clinical pouchitis concomitant with significant increases in ileal pouch MPO concentrations as well as NK-1R protein expression by Western blot analysis. In situ hybridization and immunohistochemistry showed that the increase in NK-1R protein expression was especially evident in crypt epithelia of pouch ileum. When the NK-1RA was administered 1 day before starting DSS and continued for the duration of DSS administration, the physical signs of clinical pouchitis and the rise in MPO were prevented. These data implicate SP in the pathophysiology of pouchitis and suggest that NK-1RA may be of therapeutic value in the management of clinical pouchitis.
authors.affiliation: Department of Surgery, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
authors.forename: Arthur F
authors.initials: AF
authors.lastname: Stucchi
authors.forename: Khaled O
authors.initials: KO
authors.lastname: Shebani
authors.forename: Susan E
authors.initials: SE
authors.lastname: Leeman
authors.forename: Chi-Chung
authors.initials: CC
authors.lastname: Wang
authors.forename: Karen L
authors.initials: KL
authors.lastname: Reed
authors.forename: A Brent
authors.initials: AB
authors.lastname: Fruin
authors.forename: Adam C
authors.initials: AC
authors.lastname: Gower
authors.forename: James P
authors.initials: JP
authors.lastname: McClung
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Andry
authors.forename: Michael J
authors.initials: MJ
authors.lastname: O'Brien
authors.forename: Charalabos
authors.initials: C
authors.lastname: Pothoulakis
authors.forename: James M
authors.initials: JM
authors.lastname: Becker
mesh_terms: D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D016264:Dextran Sulfate / Q000037:antagonists & inhibitors* / Q000494:pharmacology*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007413:Intestinal Mucosa / Q000187:drug effects / Q000473:pathology; D008297:Male; D064729:Neurokinin-1 Receptor Antagonists; D019449:Pouchitis / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018040:Receptors, Neurokinin-1 / Q000378:metabolism
chemical_list: C480026:6-diphenylmethyl-5-(5-isopropyl-2-methoxybenzylamino)-1-azabicyclo(2.2.2)octane-3-carboxylic acid; D019086:Bridged Bicyclo Compounds, Heterocyclic; D064729:Neurokinin-1 Receptor Antagonists; D018040:Receptors, Neurokinin-1; D016264:Dextran Sulfate