Effects of in vivo freezing and mannitol in intestinal ischaemia-reperfusion injury.

Abstract

The main purpose of this study was to investigate whether in vivo freezing and mannitol administration can protect the small intestine against ischaemia-reperfusion (I-R) injury. Fifty male Sprague-Dawley rats (200-225 g) were divided into 5 groups each containing 10 rats; group SO, sham operation group; group I, mesenteric ischaemia group; group R, ischaemia-reperfusion (I-R); group FR, I-R plus in vivo freezing; group MR, I-R plus mannitol treatment. Intestinal ischaemia for 30 min and reperfusion for 60 min were applied. Ileum specimens were obtained to determine the tissue levels of malondialdehyde (MDA) and histological changes. The mucosal injury scores of group R were significantly higher than those of the group I (P<0.0001). The mucosal injury scores in the groups FR and MR were significantly lower than the group R (P<0.0001 and P<0.0001, respectively). In the group FR, mucosal injury scores were not significantly different from those of group I (P=0.123). However, mucosal injury scores of group MR were significantly less when compared to those of group I (P=0.01). Mean MDA levels of group R were significantly higher than those of the group I (P<0.0001). Mean MDA levels of groups FR and MR were significantly lower than those of group R (P<0.0001 and P<0.0001, respectively). In addition, MDA levels of group FR were significantly higher than those of group MR (P<0.0001). In conclusion, these observations suggest that the in vivo freezing of SMA and the pre-treatment with mannitol before reperfusion period may be useful in preventing intestinal reperfusion injury.