OBJECTIVE: Establish an animal model for the Roux en Y gastric bypass and to evaluate its weight loss and amount of food intake, as well as verify macroscopic, morphometric and histopathologic aspects of the bypassed segment. METHODS: Sixteen male pigs were studied in two groups. The Group Surgery was composed of 8 animals submitted to a Roux en Y gastric bypass. The Group Control comprised 8 pigs receiving identical care, except for the surgical procedure. Group Surgery was followed for 90 days, when the bypassed gastric segment was resected. Group Control was followed for 84 days, when the stomach was resected. RESULTS: Weight loss and the amount of food intake were evaluated in both groups. Macroscopic findings, histopathologic changes of the gastric wall, gastric gland morphometry and the amount of collagen type I and III of the gastric mucosa in the bypassed gastric segment were evaluated. Group Control exhibited a significant larger weight gain and food intake compared to surgery. The gastric glands were smaller and type I collagen was predominant in Surgery compared to Control. No changes were noted in the type III collagen. Fat tissue was identified among the muscle fibers in the isolated segment of Group Surgery. CONCLUSION: This model of Roux en Y gastric bypass in pigs offers consistent weight and food intake reduction. Secondly, Roux en Y gastric bypass in pigs does not induce macroscopic changes in mucosa. Finally, the histopathological findings are consistent with initial atrophy of the isolated gastric segment.
Obesity; Morbid obesity; Surgery