Ischemia following intestinal reperfusion is a common place event that favors bacterial translocation in remote organs, such as the lungs. Previous antibioticotherapy may be an efficient procedure to lessen the hazards of this process. The purpose of this study was to analyse the concentration of polimorphonuclears (PMN) in the lung alveolar septum of rats, after induced ischemia followed by intestinal reperfusion, with and without previous antibiotictoherapy. Forty-eight rats were used, randomly divided into 6 groups of 8 animals each (A, B, C, D, E, and F). Groups A, C and E did not receive antibiotic and groups B, D and F received 500mg/Kg of erythromycin orally. Groups A and B were the control groups. In the groups C and D intestinal ischemia was induced for 30 min; and in groups E and F reperfusion for 30 min followed the ischemia. A thoracothomy was performed and the lungs were removed and sent for histopathologic and histometric analysis. The number of PMN in the alveolar septum was observed. The control group (A) showed a mean number of 4.2 PMN per field in the septum; in the ichemia group (C) , the mean number of PMN was 13.6 and in the group where the reperfusion followed ischemia (E), the number of PMN was 17,5. The comparison between the mean number of PMN in groups A and C and A and E showed a statistically significant difference (p<0.0001). However, the difference between the groups C and E was not significant (p=0.095). The mean number of PMN per field was of 8.6 in group B; 9.9 in group D and 12.9 in group F. The comparison between the groups B and D demonstrated a p=0.007. The comparison between the groups that received antibiotics or not demonstrated that the number of PMN in group B was twice as much as in group A (p=0.0049) . Group C showed a greater concentration of PMN than did group D (p=0.019). In group E there was a greater concentration of PMN than in group F (p=0.014). It may be concluded that: (1) intestinal ischemia leads to a greater PMN concentration in the alveolar septum; (2) previous antibioticotherapy increased lung inflammatory infiltrate in the alveolus of rats with normal intestines; (3) PMN density was greater in alveolar septum of animals who underwent I/R than those who were not reperfused, and (4) previous antibioticotherapy reduced significantly the PMN concentration after I/R.
Ischemia; Reperfusion; Intestines; Lung
