Publication

Effect of gastric bypass and gastric banding on proneurotensin levels in morbidly obese patients

Journal Paper/Review - Sep 1, 2006

Units
PubMed
Doi

Citation
Christ-Crain M, Müller B, Bergmann A, Struck J, Korbonits M, Bilz S, Morgenthaler N, Ernst A, Stoeckli R, Keller U. Effect of gastric bypass and gastric banding on proneurotensin levels in morbidly obese patients. The Journal of clinical endocrinology and metabolism 2006; 91:3544-7.
Type
Journal Paper/Review (English)
Journal
The Journal of clinical endocrinology and metabolism 2006; 91
Publication Date
Sep 1, 2006
Issn Print
0021-972X
Pages
3544-7
Brief description/objective

CONTEXT: Neurotensin is produced mainly in the N cells of the ileum and has a role in appetite regulation; levels are decreased in obese subjects and increase after bariatric surgery. Mature neurotensin is very unstable, with a short half-life. OBJECTIVE: The objective of this study was to compare baseline and postoperative levels of the more stable neurotensin precursor, proneurotensin/neuromedin (pro-NT/NMN), in patients after gastric banding, gastric bypass, and nonoperated controls, respectively, during long-term follow-up. DESIGN AND SETTING: This was a prospective observational study in a university hospital. PARTICIPANTS AND MAIN OUTCOME MEASURES: Overnight fasting plasma pro-NT/NMN concentrations were measured with a new sandwich immunoassay in morbidly obese subjects at baseline and 6, 12, and 24 months after gastric banding (n = 8), Roux-en-Y gastric bypass (n = 5), and in nonoperated controls (n = 7). RESULTS: After gastric bypass and banding, body weight decreased by (mean +/- sd) 29.5 +/- 5.5 and 22.8 +/- 5.9 kg, respectively. The decrease after 3 and 6 months was more pronounced after gastric bypass compared with gastric banding (P < 0.05). Plasma pro-NT/NMN levels in patients after gastric bypass increased from 246.3 +/- 174.3 pmol/liter on admission to 748.3 +/- 429.6 pmol/liter after 24 months (P < 0.01). In contrast, in patients with gastric banding, pro-NT/NMN concentrations remained stable (207.3 +/- 60.5 pmol/liter at admission, 226.6 +/- 116.8 pmol/liter after 24 months). Neither body weight nor plasma pro-NT/NMN levels changed in nonoperated controls. CONCLUSION: Plasma pro-NT/NMN levels show a more pronounced increase after gastric bypass compared with gastric banding, suggesting that specific bariatric surgical procedures result in distinct alterations of gastrointestinal hormone metabolism. The more stable precursor pro-NT/NMN provides a new tool to quantify neurotensin levels in clinical practice.