Effects of starvation and bowel resection on paracellular permeability in rat small-bowel mucosa in vitro

Background: Maintenance of intestinal integrity is essential after major ab dominal surgery in malnourished subjects. The purpose of this experimental study was to investigate factors affecting small-bowel mucosa permeability in vitro in the immediate postoperative period in starved rats. Methods: Ma le Wistar rats were randomly placed in five groups: Controls. Anesthesia Re section, Starvation, and Starvation + resection. Controls consisted of fed rats. Anesthesia was induced intraperitoneally with xylazine and ketamine. Resection was 5 cm of the mid-jejunum, and the starvation period was 48 h. Two hours after surgery stripped mucosal segments from the jejunum and the ileum were mounted in Ussing chambers, and the transmucosal permeation of C r-51-labeled ethylenediaminetetraacetic acid (EDTA) and dextran (40,000 Da) was studied for 120 min while electrophysiology was monitored. Results: St arvation increased permeability to Cr-51-EDTA in both the jejunum and ileum . Tn the jejunum permeability was further increased by starvation + resecti on. Resection or anesthesia alone did not increase permeability. The villou s height in the jejunum was reduced by starvation. Mucosal permeability was correlated to the change in transepithelial resistance during experiments. Conclusions: Starvation was the main cause of increased mucosal permeabili ty in both intestinal segments of the rat, but surgical trauma had an addit ive effect, which was most pronounced in the jejunum.