失血大鼠肠道多节段病理学评价及巨噬细胞功能研究OACSTPCD

Objective To investigate the pathological damage to and inflammation of different intestinal segments in a rat model of severe hemorrhage,and to explore the effect of polarization of intestinal macrophage on the pathophysiology of intestinal inflammation.Methods Male Wistar rats were randomly divided into two groups:the sham operation group and hemorrhage group.In the hemorrhage group,40％of the total blood volume was lost in 25-30 minutes,while in the sham operation group,only the femoral artery and vein were intubated without bleeding.The rats were killed at 0,3,6,12 and 24 hours.The entire intestine was isolated quickly,and sections of the intestine were cut at the duodenum,jejunum,ileocecal junction,colon and rectum for histopathological evaluation.ELISA was adopted to determine related inflammation factors while multi-color immunohistochemistry was used to calculate macrophage surface markers.The data was statistically analyzed.Results(1)Compared with the sham group,there was no significant difference in colon histology at 3 h and 6 h,but significant difference was detected in rectum scores only at 24 h.The scores of other intestinal segments were significantly different at each time point.The severity of ileocecal and colonic lesions after bleeding increased with time.The duodenum,jejunum and ileocecum were more critically injured at 3 h than the rectum at 6 h.The injury to the duodenum,jejunum,ileum and colon was much more pronounced than to the rectum at 12 h.(2)The expressions of TNF-α and IL-1β in the rectum were increased significantly at 12 h post operation.The expressions of IL-1β,TNF-α in the jejunum increased obviously at 3 h and 6 h,respectively.(3)Three hours after severe bleeding,the level of macrophages in the jejunum and ileocececal area increased significantly,and the percentage of M1 macrophages was higher.After 6 hours,the proportion of M2 macrophages in the jejunum and M1 macrophages decreased significantly.After 3 hours,the percentage of M1 macrophages in the colon decreased,but that of M2 macrophages increased.The proportion of M2 polarized macrophages in the duodenum and rectum increased at 3 h after severe bleeding but decreased at 6 h.Conclusion Pathological damage to intestinal sections after bleeding varies depending on the time,and is correlated with the inflammatory level of macrophages.