After a similar amount of oral and intravenous glucose has been administered, researchers evaluate the blood insulin levels of healthy volunteers. We see the following curves: Which of the following endogenous substances best explains the difference between the curves?

Question

After a similar amount of oral and intravenous glucose has been administered, researchers evaluate the blood insulin levels of healthy volunteers. We see the following curves:  Which of the following endogenous substances best explains the difference between the curves?

Quizplus · Accepted Answer

Eductional Objective: Incretins are digestive hormones made by the gut mucosa that encourage the release of insulin from the pancreas in response to meals high in sugar. This reaction happens without regard to blood sugar levels and usually comes before any rise in blood sugar after a meal. The hormones glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide are two that have incretin-like actions (glucose-dependent insulinotropic peptide, GIP). Due to the pancreatic beta-cells' sensitivity to blood glucose rises, insulin levels will likewise rise after intravenous glucose injection. However, because incretin has no impact, this increase will not be as significant as that observed after oral glucose treatment.

After a Similar Amount of Oral and Intravenous Glucose Has