Investigating the Acute Effects of Increasing Alanine Exposure in Healthy Participants

Investigating the Effect of Glucagon on Cognitive Function and Cerebral Glucose Metabolism in Humans: A Pilot Study

In this study the investigators will investigate the acute effects of increasing alanine exposure on metabolic parameters in healthy participants.

Participants will participate in one study day. After initial baseline blood samples, a three-hour intravenous infusion with glucagon will be initiated. The infusion rate will be increased every 30 minutes.

Two peripheral catheters will be placed in the antecubital vein of each arm for infusion of L-alanine and blood sampling respectively. The infusion rate of alanine will start at 1.4 μmol/kg/min and increase every 30 minutes over a 3-hour period, up to a maximum of 28 μmol/kg/min. The study day will last approximately 4 hours, and a maximal blood volume of 130 ml will be collected. Blood samples for the analysis of plasma glucagon, glucose, insulin, C-peptide etc. will be drawn every 15 minutes.

Inclusion Criteria:

• Capable of understanding the participant information and signing the consent form
• Between 25 and 70 years of age at the time of screening
• Body mass index (BMI) ≤ 25 kg/m2 at the time of screening

Exclusion Criteria:

• Enrolment in other research projects that might interfere with the study
• Diabetes diagnosis (type 1 and 2)
• Pregnancy or breastfeeding
• Use of medications which, in the opinion of the investigator, may jeopardise participant's safety or compliance with the protocol
• Impaired liver function defined as either alanine aminotransferase (ALAT) and/or aspartate aminotransferase (ASAT) ≥ 2 times normal values
• Kidney disease defined as serum creatinine levels ≥ 126 μmol/L for male and ≥ 111 μmol/L for female
• Inadequately treated blood pressure at screening defined as repeated resting blood pressure outside the range 90-150 mmHg for systolic and 50-100 mmHg for diastolic
• Active or recent malignant disease
• Current or history of severe alcohol use or drug/chemical abuse as per investigator's judgement
• Any chronic disorders or severe diseases which, in the opinion of the investigator, might jeopardise participant's safety or compliance with the protocol