Effect of surgical manipulation of the rat intestine on enterocyte populations

Background. The intestine is susceptible to operations at remote locations, and the barrier function is altered during intestinal manipulation, leading to bacterial or endotoxin translocation into the systemic circulation. One of the mainstays for the maintenance of the integrity of the barrier function is epithelial cell proliferation and migration. The present study looked at the effect of gut manipulation after laparotomy on different cell populations of the intestinal epithelium. Methods. Surgical manipulation of the gut was performed by opening the abdominal wall and handling the intestine, as is done during laparotomy. Villus and crypt cells were isolated at different time periods after gut manipulation, and mitochondria were Prepared from isolated enterocytes. The effects of surgical manipulation on enterocytes and isolated mitochondria were studied. Results. Mechanical manipulation of the gut resulted in alterations in the intestinal epithelium, as shown by decreased cell viability and yield in the crypt cells. The alterations were associated with actin reorganization, as well as with altered cell proliferation and adenosine deaminase activity. At the mitochondrial level, altered mitochondrial function, such as decreased respiratory control ratio, increased 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide reduction, and induction of permeability transition in the crypt cells, was observed. These alterations were maximal 1 hour after surgical manipulation and partially recovered to normal by 24 hours. Conclusions. Mechanical manipulation of the gut that occurs during any abdominal operation induces alterations in the intestine, both at the cellular and the subcellular levels. The crypt cells bear the brunt of the damage, and the reversibility of the damage is possibly brought about by increased proliferation and movement of the cells.