Change in intestinal free radical and prostaglandin metabolism in the aged rats with pneumococcus pneumonia

Objective: To study the pathogenic mechanism underlying intestinal injury in the aged rat with pneumonia. Methods: The model of rats with Pneumococcus pneumonia was reproduced, and animals were divided into young control group (YCG), young model group (YMG), aged control group (ACG) and aged model group (AMG). The pathological change of lung tissue and intestine, contents of intestinal 6-keto-prostaglandin F 1α(6-keto-PGF 1α), thromboxane B 2(TXB 2), nitric oxide(NO), malondialdehyde(MDA) and superoxide dismutase (SOD) activity were determined in various groups. Results: The lung and intestinal injury in AMG was more serious than that in the YMG. The decreases in SOD activity and 6-ketoPGF 1α content, the increases in contents of TXB 2, NO, MDA in the YMG and the AMG were obvious than those in the YCG and the ACG respectively. The decrease in SOD activity and increase in MDA content were obvious in the ACG than those in the YCG. In addition, the decrease in SOD activity and increase in MDA content in the AMG were significant compared with those in the YMG. Conclusion: The prostaglandin metabolism and the free radical injury might be in the pathogenesis of intestinal injury in the aged rats with pneumonia. The intestinal injury induced by free radical in aged rats with pneumonia appears to be more obvious with ageing.