Clinical Research Directory

The Effect of Glucagon on Cerebral Glucose Metabolism in Healthy Humans

This is a pilot study in which the investigators will investigate the effect of exogenous glucagon on cerebral glucose metabolism in healthy humans. Participants will participate in either part C or part D of the study, and each participant will participate in three study days. During a study day the participant will receive an intravenous infusion of either glucagon, glucose (in an adjustable rate to match to glucose concentrations achieved with the glucagon infusion) or saline. During each study day an 18F-flouro-deoxy-glucose (FDG) Positron Emission Tomography (PET)/Computed Tomography (CT) scan will be performed to quantify cerebral glucose metabolism during the first part (acute effect) of the glucagon/glucose/saline infusion (part C) or the last part (later effect) of the glucagon/glucose/saline infusion (part D).

Development of a Non-invasive Method for Quantifying Cerebral Glucose Metabolism for Studying the Effect of Glucagon in Humans

The aim of the study is to develop a non-invasive method for quantifying cerebral glucose metabolism by PET scans in humans. This method will be used in subsequent studies, where the effect of the pancreatic hormone glucagon on cerebral glucose metabolism will be studied. The golden standard for quantifying cerebral glucose metabolism by PET scans is based on arterial blood sampling, which complicates research setup. This study will investigate if image derived measurements instead of arterial blood samples can be used to quantify cerebral glucose metabolism. We will compare the calculations of cerebral glucose metabolism based on arterial blood samples and image derived measurements and hopefully these will correlate. Healthy participants will be included, and each participant will participate in one study day, which includes intravenous administration of radioactively labelled glucose (18-FDG), arterial blood sampling and PET scans.