Protective Effect of L‐Arginine Against Ibuprofen‐induced Gastric Injury in Rats

Abstract

This study has been designed to confirm the protective effect of different single oral doses of L-arginine in the presence of equimolar doses of ibuprofen, and to compare the results with those obtained after treatment with ibuprofen alone. Different parameters were assessed in rats: gastric damage (mm2 and score), ratio of lesionated stomachs/total stomachs evaluated, and presence of haemorrhage. Six hours after dosing, oral administration of ibuprofen (0·3, 0·6 and 1·2 mmol kg −1) produced a progressive dose-dependent increase in damage to the gastric mucosa. All treatments with equimolar doses of L-arginine considerably reduced lesions (mm2 and score) and the same tendency was observed with the other parameters examined. We also evaluated the gastroprotective effect of L-arginine against anti-ulcer reference drugs, ranitidine and roxatidine (two antisecretory agents) and misoprostol (a cytoprotective drug). The degree of inhibition of damage provided by L-arginine was similar to those obtained with the other drugs. Thus, we conclude that the simultaneous administration of equimolar doses of ibuprofen and L-arginine offers significant protection compared with gastrolesive doses of ibuprofen alone, with an important decrease in the lesionated areas and improvement of the vascular state. The extent of this protective action is comparable with that observed with anti-ulcer reference drugs.