Obesity Surgery

, Volume 20, Issue 5, pp 616–622 | Cite as

Vagal Sparing Surgical Technique but Not Stoma Size Affects Body Weight Loss in Rodent Model of Gastric Bypass

  • Marco Bueter
  • Christian Löwenstein
  • Hutan Ashrafian
  • Jacquelien Hillebrand
  • Stephen R. Bloom
  • Torsten Olbers
  • Thomas Lutz
  • Carel W. le Roux
Animal Research



The aim of this study was to evaluate whether gastric bypass with or without vagal preservation resulted in a different outcome.


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.


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.


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.


Gastric bypass Rats Para-oesophageal bundle Vagal nerve Left gastric vessels Weight loss 


  1. 1.
    Adams TD, Gress RE, Smith SC, et al. Long-term mortality after gastric bypass surgery. N Engl J Med. 2007;357:753–61.CrossRefPubMedGoogle Scholar
  2. 2.
    Sjostrom L, Narbro K, Sjostrom CD, et al. Effects of bariatric surgery on mortality in Swedish obese subjects. N Engl J Med. 2007;357:741–52.CrossRefPubMedGoogle Scholar
  3. 3.
    Buchwald H, Avidor Y, Braunwald E, et al. Bariatric surgery: a systematic review and meta-analysis. JAMA. 2004;292:1724–37.CrossRefPubMedGoogle Scholar
  4. 4.
    Buchwald H. Bariatric surgery for morbid obesity: health implications for patients, health professionals, and third-party payers. J Am Coll Surg. 2005;200:593–604.CrossRefPubMedGoogle Scholar
  5. 5.
    Borg CM, le Roux CW, Ghatei MA, et al. Progressive rise in gut hormone levels after Roux-en-Y gastric bypass suggests gut adaptation and explains altered satiety. Br J Surg. 2006;93:210–5.CrossRefPubMedGoogle Scholar
  6. 6.
    Bueter M, Lowenstein C, Olbers T et al. Gastric bypass increases energy expenditure in rats. Gastroenterology 2010.Google Scholar
  7. 7.
    Guijarro A, Suzuki S, Chen C, et al. Characterization of weight loss and weight regain mechanisms after Roux-en-Y gastric bypass in rats. Am J Physiol Regul Integr Comp Physiol. 2007;293:R1474–89.PubMedGoogle Scholar
  8. 8.
    Furnes MW, Tommeras K, Arum CJ, et al. Gastric bypass surgery causes body weight loss without reducing food intake in rats. Obes Surg. 2008;18:415–22.CrossRefPubMedGoogle Scholar
  9. 9.
    Furnes MW, Stenstrom B, Tommeras K, et al. Feeding behavior in rats subjected to gastrectomy or gastric bypass surgery. Eur Surg Res. 2008;40:279–88.CrossRefPubMedGoogle Scholar
  10. 10.
    Guijarro A, Osei-Hyiaman D, Harvey-White J, et al. Sustained weight loss after Roux-en-Y gastric bypass is characterized by down regulation of endocannabinoids and mitochondrial function. Ann Surg. 2008;247:779–90.CrossRefPubMedGoogle Scholar
  11. 11.
    Meguid MM, Glade MJ, Middleton FA. Weight regain after Roux-en-Y: a significant 20% complication related to PYY. Nutrition. 2008;24:832–42.CrossRefPubMedGoogle Scholar
  12. 12.
    Stenstrom B, Furnes MW, Tommeras K, et al. Mechanism of gastric bypass-induced body weight loss: one-year follow-up after micro-gastric bypass in rats. J Gastrointest Surg. 2006;10:1384–91.CrossRefPubMedGoogle Scholar
  13. 13.
    Stylopoulos N, Hoppin AG, Kaplan LM. Roux-en-Y gastric bypass enhances energy expenditure and extends lifespan in diet-induced obese rats. Obesity (Silver Spring). 2009;17:1839–47.CrossRefGoogle Scholar
  14. 14.
    Tichansky DS, Boughter Jr JD, Harper J, et al. Gastric bypass surgery in rats produces weight loss modeling after human gastric bypass. Obes Surg. 2008;18:1246–50.CrossRefPubMedGoogle Scholar
  15. 15.
    Wang Y, Liu J. Combination of bypassing stomach and vagus dissection in high-fat diet-induced obese rats-a long-term investigation. Obes Surg. 2010.Google Scholar
  16. 16.
    Perathoner A, Weiss H, Santner W, et al. Vagal nerve dissection during pouch formation in laparoscopic Roux-Y-gastric bypass for technical simplification: does it matter? Obes Surg. 2009;19:412–7.CrossRefPubMedGoogle Scholar
  17. 17.
    Sundbom M, Holdstock C, Engstrom BE, et al. Early changes in ghrelin following Roux-en-Y gastric bypass: influence of vagal nerve functionality? Obes Surg. 2007;17:304–10.CrossRefPubMedGoogle Scholar
  18. 18.
    Berthoud HR. The vagus nerve, food intake and obesity. Regul Pept. 2008;149:15–25.CrossRefPubMedGoogle Scholar
  19. 19.
    Niederhausern W.v. Recherches experimentales sur la fasciculation et la terminaison des nerfs vagues dans l'abdomen et leurs rapports avec l'innervation renale chez le rat. C.R.Assoc.Anat. 40, 783–784. 1953. Ref Type: GenericGoogle Scholar
  20. 20.
    Jackson RJ, Davis WB, Macdonald I. The energy values of carbohydrates: should bomb calorimeter data be modified? Proc Nutr Soc. 1977;36:90A.PubMedGoogle Scholar
  21. 21.
    Korner J, Bessler M, Cirilo LJ, et al. Effects of Roux-en-Y gastric bypass surgery on fasting and postprandial concentrations of plasma ghrelin, peptide YY, and insulin. J Clin Endocrinol Metab. 2005;90:359–65.CrossRefPubMedGoogle Scholar
  22. 22.
    le Roux CW, Aylwin SJ, Batterham RL, et al. Gut hormone profiles following bariatric surgery favor an anorectic state, facilitate weight loss, and improve metabolic parameters. Ann Surg. 2006;243:108–14.CrossRefPubMedGoogle Scholar
  23. 23.
    Batterham RL, Cowley MA, Small CJ, et al. Gut hormone PYY(3-36) physiologically inhibits food intake. Nature. 2002;418:650–4.CrossRefPubMedGoogle Scholar
  24. 24.
    Batterham RL, Cohen MA, Ellis SM, et al. Inhibition of food intake in obese subjects by peptide YY3-36. N Engl J Med. 2003;349:941–8.CrossRefPubMedGoogle Scholar
  25. 25.
    Cone RD, Cowley MA, Butler AA, et al. The arcuate nucleus as a conduit for diverse signals relevant to energy homeostasis. Int J Obes Relat Metab Disord. 2001;25 Suppl 5:S63–7.CrossRefPubMedGoogle Scholar
  26. 26.
    Larsen PJ, Tang-Christensen M, Jessop DS. Central administration of glucagon-like peptide-1 activates hypothalamic neuroendocrine neurons in the rat. Endocrinology. 1997;138:4445–55.CrossRefPubMedGoogle Scholar
  27. 27.
    Abbott CR, Monteiro M, Small CJ, et al. The inhibitory effects of peripheral administration of peptide YY(3-36) and glucagon-like peptide-1 on food intake are attenuated by ablation of the vagal-brainstem-hypothalamic pathway. Brain Res. 2005;1044:127–31.CrossRefPubMedGoogle Scholar
  28. 28.
    Muller MK, Rader S, Wildi S, et al. Long-term follow-up of proximal versus distal laparoscopic gastric bypass for morbid obesity. Br J Surg. 2008;95:1375–9.CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science + Business Media, LLC 2010

Authors and Affiliations

  • Marco Bueter
    • 1
    • 2
  • Christian Löwenstein
    • 3
  • Hutan Ashrafian
    • 1
  • Jacquelien Hillebrand
    • 4
  • Stephen R. Bloom
    • 1
  • Torsten Olbers
    • 1
  • Thomas Lutz
    • 3
  • Carel W. le Roux
    • 1
  1. 1.Imperial Weight Centre, Department of Investigative Medicine, Hammersmith HospitalImperial College LondonLondonUK
  2. 2.Department of SurgeryUniversity of WürzburgWürzburgGermany
  3. 3.Institute of Veterinary Physiology and Zürich Centre for Integrative Human Physiology, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
  4. 4.Swiss Federal Institute of TechnologyPhysiology and Behavior GroupSchwerzenbachSwitzerland

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