Changes in the inflammatory mediator content in the colonic mucosae of immune colitides in guinea pigs (Abstract)
An immune colitis based on a delayed-type hypersensitivity reaction was induced in dinitrochlorobenzene (DNCB) sensitized guinea pigs by intrarectal challenge with DNCB in Orabase (Squibb Ltd.)1. A low challenge dose (0.25% DNCB), given once daily for 5 days induced mild inflammatory changes in the distal colon and rectum characterized by goblet cell depletion and mild cellular infiltration of the mucosa and submucosa. A higher challenge concentration (5% DNCB) given once daily for 3 days resulted in severe colonic ulceration with crypt abscess formation and a heavy cellular infiltrate in the mucosa and sub-mucosa. Diarrhoea, rectal bleeding and body weight loss were also prominent features. The inflammatory mediators, histamine, 5-HT, glandular kallikrein and PGE2 were measured in freeze-dried colonic mucosae of the two colitides. Histamine content was 3 times control (p< 0.01) in 0.25% DNCB induced colitis, although no significant change was observed in 5% DNCB challenged animals. Mucosal 5-HT content was significantly reduced (p < 0.01) in both models. Glandular kallikrein content did not differ from control (p > 0.05) PGE2 was significantly increased (p < 0.05) in both models. The possible significance of these changes with respect to severity of inflammation and aetiology of colitis is described.
KeywordsColonic Mucosa Rectal Bleeding Distal Colon Time Control Body Weight Loss
- Lewis, A. J., Norris, A. A. and Zeitlin, I. J. (1979). Br. J. Pharmac, 66, 499PGoogle Scholar