Systemic GLP-2 levels do not limit adaptation after distal intestinal resection.

BACKGROUND/PURPOSE: Glucagonlike peptide 2 (GLP-2) is trophic for the small bowel; it is produced by L cells in the distal intestine in response to luminal nutrients. This study tests the hypothesis that distal small bowel and cecal resection would decrease GLP-2 levels and reduce adaptation.

METHODS

Male Sprague-Dawley rats (200 to 300 g) underwent either ileal transection (controls) or resection of the ileum and cecum, leaving 10 or 20 cm jejunal remnant anastomosed to the ascending colon. Animals were followed up for up to 21 days. Endpoints were daily weights, intestinal histology, in vivo absorption of 3-0 methylglucose (a measurement of active nutrient absorptive capacity), and serum GLP-2 levels.

RESULTS

The control group had a maximum 6% weight loss around day 2, and then recovered with a steady weight gain. The 10-cm jejunal remnant group lost weight continuously and never recovered postsurgery. The 20-cm jejunal remnant group of animals had a maximum of 12% weight loss by day 4 and then slowly gained weight. The average villus height increased significantly (P <.01) in the 10-cm and 20-cm jejunal remnant groups compared with controls. Absorption of 3-0 methylglucose was significantly decreased (P <.01) in both resected groups. Serum GLP-2 levels were increased significantly (P <.05) when compared with controls in both resection groups.

CONCLUSIONS

Increased serum GLP-2 levels were found in the ileocecal resection rat model, and these levels correlated with morphologic adaptation. However, this morphologic adaptation was not sufficient to restore nutrient absorption as shown by weight changes and 3-0 methylglucose absorption. Thus, the original hypothesis of this study is incorrect: systemic GLP-2 levels do not limit adaptation following distal ileocecal resection.