Evaluating the prophylactic potential of zafirlukast against the toxic effects of acetic acid on the rat colon.

The present work was conducted to assess the possible protective effects of zafirlukast against the toxic damage induced by acetic acid in rat colon. Zafirlukast is a potent and selective cysteinyl leukotriene receptor antagonist which is used mainly in the prophylaxis of bronchial asthma. Two doses of zafirlukast were used (40 and 80 mg/kg) dissolved in gum acacia and given either orally or rectally (0.5 ml/kg). Several parameters including, macroscopic score, histopathological and biochemical such as malondialdehyde (MDA), myeloperoxidase (MPO), catalase and reduced glutathione (GSH) levels were measured using standard assay procedures. The study showed that pretreatment with zafirlukast in a dose of 80 mg/kg orally produced a significant decrease in tissue malondialdehyde, myeloperoxidase, and an increase in both reduced glutathione and catalase levels, while there was no significant changes with the rectal route. The 40 mg/kg dose had no significant protective effects when given either orally or rectally. The available data indicate that the inhibition of leukotriene synthesis or action may have a role in inflammatory bowel disease (IBD) as they are considered as important mediators in this condition.