Effects of flunixin meglumine on the recovery of ischaemic equine colonic mucosa in vitro

Abstract

Reasons for performing study: The effects of prostaglandins and nonsteroidal anti-inflammatory drugs (NSAIDs) on repair of equine intestinal mucosa are important since most horses with gastrointestinal diseases are routinely treated with NSAIDs, such as flunixin meglumine (FM), and these drugs can be toxic to equine gastrointestinal mucosa. Hypothesis: Flunixin meglumine would not affect recovery of equine colonic mucosa in vitro, 18h after a reversible ischaemic injury. Methods: In 14 anaesthetised horses, a segment of pelvic flexure was subjected to 2h of ischaemia and the horses were allowed to recover for 18h. Seven horses received normal saline and 7 received FM, 1.1mg/kgbwti.v., at the end of ischaemia and 12h later. Colonic mucosa was harvested during a second anaesthesia, 18h after recovery from ischaemia and then horses were subjected to euthanasia. Transepithelial electrical resistance (TER) and transepithelial flux of tritiated mannitol were used to measure mucosal permeability during 4h of incubation in Ussing chambers, with the following in vitro treatments: 1) no addition, 2) FM 14μmol/l as powder, 3) FM 14μmol/l in injectable form and 4) diluent for injectable FM. Histomorphological changes were assessed by light microscopy. Results: There were no significant differences in any of the measurements between saline and FM treated horses. The mucosal height of the ischaemic FM tissues incubated in diluent was significantly decreased compared to the nonischaemic tissues. Conclusions: Flunixin meglumine did not adversely affect barrier integrity in ischaemic equine colonic mucosa. © 2011 EVJ Ltd.