AIM:To investigate whether oral glutamine pretreatment prevents impairment of intestinal mucosal integrity during ischemia-reperfusion (I/R) in rats. METHODS: The study was performed as two series with 40 rats in each. Each series of animals was divided into four groups. The first group was used as a control. Animals in the second group were only pretreated with oral glutamine, 1 g/kg for 4 d. The third group received a normal diet, and underwent intestinal I/R, while the fourth group was pretreated with oral glutamine in the same way, and underwent intestinal I/R. Intestinal mucosal permeability to 51Cr-labeled EDTA was measured in urine in the first series of animals. In the second series, histopathological changes in intestinal tissue and plasma endotoxin levels were evaluated. RESULTS: Intestinal I/R produced a significant increase in intestinal permeability, plasma endotoxin level and worsened histopathological alterations. After intestinal I/R, permeability was significantly lower in glutamine- treated rats compared to those which received a normal diet. However, no significant change was observed in plasma endotoxin levels or histopathological findings. CONCLUSION: Although glutamine pretreatment seems to be protective of intestinal integrity, upon I/R injury, such an effect was not observable in the histopathological changes or plasma endotoxin level. A series of animals is divided into four groups. AIM: To investigate whether oral glutamine pretreatment prevents impairment of intestinal mucosal integrity during ischemia-reperfusion (I / R) in rats. METHODS: The study was performed as two series with 40 rats in each. Each series of animals was divided into four groups The first group was used as a control. Animals in the second group were pretreated with oral glutamine, 1 g / kg for 4 d. The third group received a normal diet, and underwent intestinal I / R, while the fourth group was Intestinal mucosal permeability to 51Cr-labeled EDTA was measured in urine in the first series of animals. In the second series, histopathological changes in intestinal tissue and plasma endotoxin levels were as. RESULTS: Intestinal I / R produced a significant increase in intestinal permeability, plasma endotoxin level and worsened histopathological alterations. After intestinal I / R, permeability was significantly lowe However, no significant change was observed in plasma endotoxin levels or histopathological findings. CONCLUSION: Although glutamine pretreatment seems to be protective of intestinal integrity, upon I / R injury, such an effect was not observable in the histopathological changes or plasma endotoxin level.