The mechanisms involved in the weight loss seen after Vertical Sleeve Gastrectomy (VSG) are not clear. The rat stomach has two morphologically and functionally distinct proximal and distal parts. The rat model for VSG involves complete removal of the proximal part and 80% removal of the distal part along the greater curvature. The purpose of this study was to understand the potential independent contributions of removal of these distinct gastric sections to VSG outcomes. We prepared four surgical groups of male Long Evans rats; VSG, sham-surgery (control), selective proximal section removal (PR) and selective distal section removal (DR). GER was highest after VSG compared to all other groups. However, PR, in turn, had significantly greater GER compared to both DR and sham groups. The surgery-induced weight loss followed the same pattern with VSG causing the greatest weight loss and PR having greater weight loss compared to DR and sham groups. The results were robust for rats fed regular chow or a high-fat diet. Body mass analysis revealed that the weight loss was due to loss of fat mass and there was no change in lean mass after the surgeries. In conclusion, removal of the proximal stomach contributes to most, but not all of the physiological impact of VSG.
- Sleeve Gastrectomy
- Weight Loss
- Gastric Emptying Rate
- Copyright © 2016, American Journal of Physiology-Regulatory, Integrative and Comparative Physiology