Background. We examined the effects of intraluminal nitroglycerin (NTG) on various physiologic functions and intestinal pathology in intestinal ischemia-reperfusion (IR) injury in rats. Materials and methods. Intraluminal NTG (0.15-3.75 mg/kg) was administered at different doses and stages during the experimental disease, and intestinal permeability and histology, bile flow, and systemic hemodynamics were measured. Results. Prophylactic intraluminal NTG treatment at 0.75 mg/kg, but not at 0.15 mg/kg, significantly attenuated the deleterious changes in intestinal barrier function and mucosal injury caused by IR. However, administration of NTG after ischemia was not effective, even up to 3.75 mg/kg. In vitro intestinal NTG metabolism was significantly decreased following intestinal ischemia. Intraluminal NTG at 0.75 mg/kg significantly attenuated. the reduction in bile flow that accompanied IR. Reperfusion induced a precipitous and sustained decrease in mean arterial pressure, which was blunted by intraluminal NTG. Conclusions. Intraluminal NTG produced several beneficial local and systemic effects in a rat model of intestinal IR. In this disease model, 0.75 mg/kg intraluminal NTG did not exacerbate, but rather reduced, the hypotensive effects induced by IR. (C) 2003 Elsevier Inc. All rights reserved.