Surgical stress and the small intestine: Role of oxygen free radicals

Background. Any surgical procedure can be associated with altered intestina l function. The mechanism involved in these changes at the cellular level d uring surgical stress has not been worked out. This study looked at the bio chemical and functional alterations, along with ultrastructural changes, in the intestine during surgical stress in a simple rat model. Methods. Surgical stress was induced by opening the abdominal wall and hand ling the intestine as during laparotomy. The effect of oxidative stress on the enterocyte and altered intestinal permeability as well as the ultrastru ctural changes to the mucosa were studied. Results. Surgical stress results in oxidative stress on enterocytes, as evi denced by increased xanthine oxidase and decreased catalase activity along with altered thiol redox status. This was associated with increased intesti nal permeability and widened intercellular spaces. These changes were promi nent at 60 minutes after laparotomy and returned to normal by 24 hours. Conclusions. Mild intestinal handling is capable of inducing oxidative stre ss in enterocytes; this could be one of the mechanisms by which intestinal mucosal alterations occur during surgical stress.