The delays in intestinal motility and neutrophil infiltration following burn injury in rats involve endogenous endothelins

This study was carried out to investigate the role of endogenous endothelin s in intestinal motility following bum injury by using a nonselective endot helin-1 (ET-1) antagonist and to evaluate the ET-1-mediated reactive oxygen metabolite formation and neutrophil infiltration following burn injury. In 2 h and 3 day postburn groups, transit indices were significantly decrease d as compared to corresponding sham groups. Transit index was not significa ntly changed by PD156252 pretreatment in the 2 h postburn group, whereas th e delay in transit was abolished in the ET-antagonist treated 3 day postbum group. In the 2 h postburn group, tissue-associated myeloperoxidase (MPO) activity value was found to be increased compared to corresponding sham gro up, while PD156252 pretreatment partially reversed this effect. Although MP O activity levels were not significantly different between 3 day postburn a nd corresponding sham groups, MPO levels showed a significant increase in E T antagonist-treated group as compared to the corresponding burn group. In the early phase of the burn, there was no significant difference in protein oxidation levels among the groups. In the 3 day postburn group, protein ox idation levels in ET-antagonist-treated group showed an increase compared t o its corresponding burn group. In conclusion, the results demonstrate that endogenous endothelins have an important role in the systemic response to burn injury, as observed by a delay in intestinal motility and an infiltrat ion of neutrophils. Although the results of the animal studies are not read ily applicable to burned patients, the present study may suggest that the b urned patient's condition should be carefully evaluated to secure a proper and early enteral feeding. (C) 2000 Elsevier Science Ltd and ISBI. All righ ts reserved.