Effect of gastric volume or emptying on meal-related symptoms after liquid nutrients in obesity: a pharmacologic study.
OBJECTIVE
Altered postprandial satiation influences food intake in obesity. The aim of this study was to evaluate the contribution of gastric motor functions to intra- and postprandial symptoms in obese, otherwise healthy, people.


METHODS
In a randomized, parallel-group, double-blind design, 40 obese (body mass index>30 kg/m2) healthy volunteers (n=10/group) received intravenous saline (placebo), atropine (.02 mg/kg), or erythromycin (1 or 3 mg/kg) to alter gastric volume and emptying after liquid nutrient meals, measured by validated imaging methods. The nutrient drink test assessed the volume ingested at maximum satiation, and intra- and early postprandial symptoms. Relationships between gastric motor functions, meal size, and symptoms were assessed by using multiple regression. Circulating levels of candidate upper-gut hormones involved in satiation were measured.


RESULTS
Relative to placebo, atropine retarded gastric emptying and increased gastric volumes; erythromycin accelerated gastric emptying and reduced gastric volumes during fasting. Although similar maximal tolerated volumes were recorded across treatments, intra- and immediate postprandial symptoms were increased by these perturbations, particularly nausea and bloating. Upper-gut hormonal profiles generally reflected changes in gastric emptying. Regression analysis showed that fasting predrug gastric volume was a significant predictor of intra- and postprandial bloating. Change in gastric volume postdrug or postmeal did not contribute additionally to predicting intra- or postprandial symptoms. There was significant (negative) association between gastric emptying and fullness score, and significant (positive) association with hunger score 30 minutes postprandially.


CONCLUSIONS
In obese individuals, fasting gastric volumes and gastric emptying, but not postprandial gastric volumes, were associated with intra- and postprandial symptoms. Understanding the determinants of gastric volume may provide insights on mechanisms controlling satiation.
Delgado-Aros
Silvia
S
Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER) Program, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.
Camilleri
Michael
M
Castillo
E Janet
EJ
Cremonini
Filippo
F
Stephens
Debra
D
Ferber
Irene
I
Baxter
Kari
K
Burton
Duane
D
Zinsmeister
Alan R
AR
D000293:Adolescent; D000328:Adult; D000368:Aged; D001285:Atropine / Q000494:pharmacology; D004311:Double-Blind Method; D004917:Erythromycin / Q000494:pharmacology; D005260:Female; D005746:Gastric Emptying / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy* / Q000503:physiopathology*; D010191:Pancreatic Polypeptide / Q000097:blood; D012044:Regression Analysis; D013270:Stomach / Q000187:drug effects / Q000503:physiopathology*
D010191:Pancreatic Polypeptide; D004917:Erythromycin; D001285:Atropine