The role of histamine in experimental ulcerative colitis in rats

Influence of the H3/H4 receptor antagonist, thioperamide on regional haemodynamics in rats with trinitrobenzene sulfonic acid-induced colitis

“…The study supports and extends our previous observations [3] that thioperamide treatment accelerates healing processes in the rat infl amed colon.…”

“…Repeated administration of histamine receptor antagonists: ketotifen, ranitidine and thioperamide, exert positive effects against experimentally induced colonic lesions in rats [3]. While ketotifen and ranitidine act primarily on H 1 and H 2 receptors, respectively, thioperamide is a dual H 3 /H 4 ligand [4].…”

International Union of Basic and Clinical Pharmacology. XCVIII. Histamine Receptors

“…The first in vivo reports of H 4 receptor activity involved neutrophilia models induced by the TLR ligand zymosan where H 4 receptor antagonists were shown to be anti-inflammatory (Gantner et al, 2002;Thurmond et al, 2004). Effects on neutrophils can also be seen in a rat colitis model where treatment with H 4 receptor antagonists reduced tissue damage, neutrophilia, and tissue TNFa levels (Fogel et al, 2005;Varga et al, 2005). Treatment with JNJ-7777120 was protective in a model of gastric ulceration .…”

The effects of diamine oxidase administration on experimental ulcerative colitis in rats

“…UC was induced by intrarectal administration of 4 % (v/v) acetic acid for 15 s. Commercially available hog kidney DAO (Sigma), immobilised on Concanavalin A-Sepharose was given to rats as a suspension of 25 mU/d, intraperitoneally, until the 5th day, when the animals were sacrifi ced. The severity of colonic lesions was evaluated using a ten point rating scale and infl ammation by measurements of plasma ceruloplasmin (Cp) and colonic myeloperoxidase (MPO) activities [3]. The colonic HA concentrations and DAO and histamine N-methyltransferase (HMT) activities were also estimated [3].…”

“…Histamine (HA) has been suggested to be involved in the pathogenesis of UC [1][2], and we have attempted to interfere with the endogenous HA system using pharmacological tools. H 1 -, H 2 -and H 3 -histamine receptor antagonists administered repeatedly to UC-rats exerted positive effects against experimentally induced colonic lesions in these animals [3]. Both mast cell hyperplasia and enhanced release of intestinal mast cell mediators [1][2] are characteristic features of UC as is reduced activity of histaminase, i. e. diamine oxidase (DAO) [4].…”