Development and Evaluation of a Glucagon Sensitivity Test in Individuals With and Without Hepatic Steatosis

"The test consists of two experimental study days:~Day 1: intravenous bolus-injection of glucagon (0.2 mg at time 0 minutes) evaluating the effect of exogenous glucagon on amino acid disappearance. Blood samples will be obtained from time -10 to 120 minutes.~Day 2: 45-minute intravenous infusion of mixed amino acids (331 mg/min/kg body weight from time 0-45 minutes) to evaluate the effect of endogenous glucagon on amino acid metabolism. Blood samples will be obtained from time -10 to 180 minutes.~All participants will be subjected to a magnetic resonance imaging scan to assess whole-liver steatosis, and a bioelectrical impedance analysis to assess body composition.~Following study inclusion and the magnetic resonance imaging scan, participants will be stratified into groups based on hepatic steatosis. Individuals with \<5.6 % hepatic steatosis will be classified as controls and individuals with ≥5.6 % hepatic steatosis will be classified as MASLD."