Pancreatic islet isolation after gastric bypass in a rat model: technique and initial results for a promising research tool

Background: Roux-en-Y gastric bypass (RYGB) affords a high remission rate of type 2 diabetes mellitus among morbidly obese diabetic patients We report the use of the isolated islet technique to assess pancreatic function and glucoregulatory mechanisms after RYGB surgery Methods: A total of 15 adult, male, Sprague Dawley diet-induced obese rats were randomly divided into 3 experimental groups sham, RYGB, and pair-fed. with 5 rats in each group The body weight was measured at baseline and every week for 4 weeks Pancreatic islet function was assessed in vitro according to the amount of insulin secreted from isolated islets incubated in 2 mM and 20 mM glucose for 1 hour at 37 degrees C Fasting plasma glucose, insulin, glucagon-like peptide-1, PYY3-36, and glucose-dependent insulmotropic peptide were measured at baseline and 28 days after surgery Results: The baseline body weight was 917 +/- 61. 831 +/- 42, and 927 +/- 43 g for the sham. RYGB, and pair-fed groups. respectively The RYGB group lost 32% body weight compared with 16% for the sham and 24% for the pair-fed groups Glucose-stimulated insulin secretion from the isolated islets in the RYGB group was greater than in the comparison groups (P = 04) at 4 weeks after surgery. Fasting plasma glucagon-like peptide-1 and PYY3-36 were significantly increased at 4 weeks in the RYGB group Conclusion: Islet isolation and stimulation in the present animal model was feasible. affords a direct measurement of pancreatic islet function, and might provide a useful tool to study the effects of RYGB on pancreatic function and the relationship between islet cell function and incretin production alter bariatric surgery (Surg Obes Relat Dis 2010,6 532-537) (c) 2010 American Society for Metabolic and Bariatric Surgery All rights reserved