title: Vagal sparing surgical technique but not stoma size affects body weight loss in rodent model of gastric bypass.
abstract: BACKGROUND
  The aim of this study was to evaluate whether gastric bypass with or without vagal preservation resulted in a different outcome.
  
  
  METHODS
  Body weight, food intake and postprandial peptide YY (PYY) and glucagon-like peptide (GLP-1) levels were compared between gastric bypass (n = 55) and sham-operated rats (n = 27) in three groups. In group 1 (n = 17), the vagal nerve was not preserved, while in group 2 the vagal nerve was preserved during gastric bypass (n = 10). In group 3, gastric bypass rats (n = 28) were randomised for either one of the two techniques.
  
  
  RESULTS
  Rats in which the vagal nerve was preserved during gastric bypass showed a lower body weight (p < 0.001) and reduced food intake (p < 0.001) compared to rats in which the vagal nerve was not preserved during the gastric bypass operation. Levels of PYY and GLP-1 were significantly increased after gastric bypass compared to sham-operated controls (p < 0.05), but there was no difference between gastric bypass rats with and without vagal preservation. Differences in food intake and body weight were not related to the size of the gastro-jejunostomy in gastric bypass rats. There were no signs of malabsorption or inflammation after gastric bypass.
  
  
  CONCLUSIONS
  We propose that the vagal nerve should be preserved during the gastric bypass operation as this might play an important role for the mechanisms that induce weight loss and reduce food intake in rats. In contrast, the gastro-jejunal stoma size was found to be of minor relevance.
authors.affiliation: Imperial Weight Centre, Department of Investigative Medicine, Hammersmith Hospital, Imperial College London, Du Cane Road, London W12 0NN, UK. m.bueter@imperial.ac.uk
authors.forename: Marco
authors.initials: M
authors.lastname: Bueter
authors.forename: Christian
authors.initials: C
authors.lastname: Löwenstein
authors.forename: Hutan
authors.initials: H
authors.lastname: Ashrafian
authors.forename: Jacquelien
authors.initials: J
authors.lastname: Hillebrand
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Bloom
authors.forename: Torsten
authors.initials: T
authors.lastname: Olbers
authors.forename: Thomas
authors.initials: T
authors.lastname: Lutz
authors.forename: Carel W
authors.initials: CW
authors.lastname: le Roux
mesh_terms: D000818:Animals; D015390:Gastric Bypass / Q000379:methods*; D005774:Gastrostomy; D052216:Glucagon-Like Peptide 1 / Q000032:analysis; D007582:Jejunostomy; D008297:Male; D009767:Obesity, Morbid / Q000378:metabolism / Q000601:surgery*; D019894:Peptide YY / Q000032:analysis; D019518:Postprandial Period; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D016896:Treatment Outcome; D014630:Vagus Nerve / Q000601:surgery*; D015431:Weight Loss
chemical_list: D019894:Peptide YY; D052216:Glucagon-Like Peptide 1