Plasma ghrelin levels of gastrectomized and vagotomized patients are not affected by glucose administration

Summary Background Ghrelin is a brain–gut peptide with GH‐releasing and appetite‐inducing activities, secreted mainly by the stomach. Circulating ghrelin concentrations fall rapidly after nutrient ingestion as well as after oral and intravenous glucose challenge. A number of gut hormones including ghrelin require an intact vagal system, which has been hypothesized to have a major role in initiating the postprandial fall in ghrelin levels. Aim We aimed to investigate the effect of oral glucose challenge on ghrelin secretion in gastrectomized (GASTRX) and vagotomized patients. Design Interventional study. Patients Six GASTRX–vagotomized patients and 11 healthy sex‐ and body mass index (BMI)‐matched subjects. Methods An oral glucose tolerance test (OGTT) was performed in all subjects. At baseline, circulating plasma total ghrelin, serum glucose, insulin and GH levels were measured. Serum glucose, insulin, GH and plasma ghrelin levels were determined every 30 min for 2 h. Results Plasma ghrelin levels at baseline were reduced by 55% in GASTRX–vagotomized patients compared to the control group (P