Exaggerated glucagon-like peptide-1 and blunted glucose-dependent insulinotropic peptide secretion are associated with Roux-en-Y gastric bypass but not adjustable gastric banding

Surg Obes Relat Dis. 2007 Nov-Dec;3(6):597-601. doi: 10.1016/j.soard.2007.08.004. Epub 2007 Oct 23.


Background: The aim of this study was to measure the circulating levels of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and glucagon in patients who had undergone adjustable gastric banding (BND) or Roux-en-Y gastric bypass (RYGB) to understand the differences in glucose and insulin regulation after these procedures.

Methods: This was a cross-sectional study of 3 groups of women matched for age and body mass index: group 1, overweight controls (n = 13); group 2, BND (n = 10); and group 3, RYGB (n = 13). Venous blood was drawn with the patient in the fasted state and throughout a 3-hour period after a liquid meal.

Results: The fasting glucose level was similar between the 2 surgery groups; however, the fasting insulin concentrations were greater in the BND (10.0 microU/mL) than in the RYGB (6.2 microU/mL; P <0.05) group. The glucose level at 60 minutes was significantly lower in the RYGB group (70 mg/dL, range 38-82) than in the BND group (83 mg/dL, range 63-98). The GLP-1 levels at 30 minutes were more than threefold greater in the RYGB group (96 pmol/L) compared with the BND and overweight control (28 pmol/L) groups. The GLP-1 and insulin concentrations correlated at 30 minutes only in the RYGB group (r = .66; P = .013). The glucose-dependent insulinotropic peptide levels at 30 minutes were lower in the RYGB group (20 pmol/L) than in the BND group (31 pmol/L) or overweight control group (33 pmol/L). The peak glucagon levels were similar among the 3 groups.

Conclusion: Exaggerated postprandial GLP-1 and blunted glucose-dependent insulinotropic peptide secretion after RYGB might contribute to the greater weight loss and improved glucose homeostasis compared with BND.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Analysis of Variance
  • Cross-Sectional Studies
  • Female
  • Gastric Bypass*
  • Gastric Inhibitory Polypeptide / metabolism*
  • Gastroplasty*
  • Glucagon / metabolism
  • Glucagon-Like Peptide 1 / metabolism*
  • Humans
  • Middle Aged
  • Obesity, Morbid / metabolism*
  • Obesity, Morbid / surgery*
  • Postprandial Period


  • Gastric Inhibitory Polypeptide
  • Glucagon-Like Peptide 1
  • Glucagon