1215-P: Effects of Exogenous Secretin on Postprandial Plasma Glucose and Lipids and Gallbladder Motility and Hemodynamics in Man

Abstract

Secretin is best known for its effect on pancreatic exocrine secretion. It also has osmoregulatory effects and was recently identified as a potential target for the treatment of obesity. We investigated the effects of a 5-hour intravenous (iv) secretin infusion on postprandial plasma glucose and lipids and gallbladder motility as well as hemodynamics in healthy males. In a randomized, double-blind, placebo-controlled, crossover study, 25 healthy males (25.7 ± 6.1 (mean ± SD) years; BMI 23.4 ± 1.8 kg/m2) underwent two 5-hour iv infusions of secretin (1 pmol/kg/min) or placebo (saline), with an interposed 8-week washout period. After 30 minutes of infusion, a standardized liquid mixed meal was ingested. Prior to and with regular intervals during the 5-hour infusions, blood samples were drawn, ultrasonography of the gallbladder performed, and hemodynamics measured. Steady-state plasma concentrations of secretin amounted to 113 ± 2 pmol/L, i.e., ~20-fold higher than physiological levels. Postprandial plasma triglyceride excursions were higher during secretin than placebo infusions (baseline-subtracted area under curve: 111 ± 49 vs. 83 ± 36 min × pmol/L [P = 0.012]), whereas excursions in glucose, glycerol and free fatty acids were similar during placebo and secretin infusions. Compared to placebo, secretin reduced maximum gallbladder ejection fraction by 32 ± 27% (P <0.001) and increased mean systolic and diastolic blood pressure by 5.3 ± 4.5 (P <0.039) and 2.2 ± 3.2 mmHg (P <0.001), respectively, and increased heart rate by 5.5 ± 3.6 bpm (P <0.001). We conclude that a 5-hour iv infusion of secretin in healthy males has no effect on fasting and postprandial glucose levels, but reduces postprandial gallbladder contraction, while increasing plasma triglycerides, blood pressure and pulse. Disclosure M. J. Bentzen: None. S. M. Nguyen heimbürger: Speaker’s Bureau; Self; AstraZeneca. B. Hartmann: None. J. J. Holst: Consultant; Self; Novo Nordisk, Other Relationship; Self; Antag Therapeutics, Bainan Biotech, MSD Corporation, Novo Nordisk, Other Relationship; Spouse/Partner; Antag Therapeutics, Bainan Biotech, Synklino ApS. M. B. Christensen: None. F. K. Knop: Advisory Panel; Self; MSD Corporation, Novo Nordisk A/S, Sanofi, Consultant; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, Novo Nordisk A/S, Pharmacosmos, Zealand Pharma A/S, Research Support; Self; Novo Nordisk A/S, Zealand Pharma A/S, Speaker’s Bureau; Self; AstraZeneca, Bayer AG, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, MSD Corporation, Novo Nordisk A/S.