Epinephrine are prepared in 100 ml isotone saline solution according to weight and infused in 3 different infusion rates: 10 ng∙kg-1∙min-1, 25 ng∙kg-1∙min-1 and 50 ng∙kg-1∙min-1, for 20 minutes each. After each adrenaline infusion, substrate response will be measured by blood samples of glucose, lactate, free fatty acids, alanine, β-hydroxybutyrate, glycerol and insulin. Furthermore, cardiovascular measurements such as pulse and blood pressure are monitored as well.

With the study subject resting in the supine position, the skin is disinfected on the lateral side of the thigh around 15 cm above the knee, with chlorhexidine alcohol. Then 3-4 mL of local anaesthetic (lidocaine 20 mg/mL) is injected into the skin, subcutaneous tissue and in the upper part of the muscle with a very thin needle. When the anaesthetic effect has set in after a couple of minutes an insertion is made in the skin and the subcutaneous tissue through which the biopsy cannula is inserted into the muscle. A small piece (around 150 mg) of the muscle is collected, which may be experienced as somewhat unpleasant, but will last for a very short while ( ~1-2 seconds). The needle is removed, a sterile Band-Aid is applied, and the study subject can leave the site after termination of the trial. The biopsy may cause some muscular tenderness for 2-3 days corresponding to minor muscular trauma.

With the study subject resting in the supine position, the skin is disinfected on one side of the abdomen around 5-10 cm lateral from the umbilicus to the knee, with chlorhexidine alcohol. Then 3-4 mL of local anaesthetic (lidocaine 20 mg/mL) is injected into the skin, subcutaneous tissue and in the upper part of the adipose tissue with a very thin needle. When the anaesthetic effect has set in after a couple of minutes an insertion is made in the skin and the subcutaneous tissue through which the biopsy cannula is inserted into the adipose tissue. A small piece (around 1 gram) of the adipose tissue is collected, which may be experienced as somewhat unpleasant, but will last for a very short while ( ~1-2 seconds). The needle is removed, a sterile Band-Aid is applied, and the study subject can leave the site after termination of the trial. The biopsy may cause some tenderness for 2-3 days corresponding to minor trauma.

Glucagon is prepared in doses of 10 µg, 25 µg, and 50 µg and intravenously injected with intervals of 2 hours. After each glucagon injection, blood samples will be drawn to measure plasma glucose, glucagon, lactate, free fatty acids, alanine, amino-acids, β-hydroxybutyrate, glycerol and insulin. Furthermore, cardiovascular measurements such as pulse and blood pressure are monitored as well.

All potential subjects will receive a blinded continuous glucose sensor at Visit 1. At the following visits, the continuous glucose monitor (CGM) will be reviewed for hypoglycaemia episodes and replaced at the same time. At Visit 2 a final screening of the inclusion criteria will take place, which involves the CGM data of the first week. A blinded CGM will be installed a week before every visit.

Subjects will undergo a hyperinsulinemic euglycaemic glucose clamp, as mentioned above, in the MRI scanning room. After 30 minutes of stable normoglycaemia, subjects are taken into the MRI scanner (Philips Achieva 7.0 T) where brain, liver, thigh and calf muscle are scanned. After every anatomically different area, the subjects must be taken out of the scanner, while scanning coils are replaced. All subjects are advised to lie still and press the alarm button if necessary.

Resting metabolic rate will be estimated, after reaching stable plasma glucose level, via a hyperinsulinemic euglycaemic clamp, as mentioned above. This will be done by indirect calorimetry, using a ventilated hood system (Jaeger Oxycon Champion, software version 4.3, Jaeger, Mijnhardt). Subjects are instructed to lie down and rest for a period of 30 minutes. Subjects are also instructed not to move, talk or sleep unless necessary during the period of measurement. The recorded measurement after 5 minutes to 30 minutes will be used for analysis.

Thermography (Thermovision SC645, FLIR Systems, Wilsonville, OR, USA) is used to determine cutaneous vascular perfusion. Data is analogue-digital converted and sampled at 100 Hz (Powerlab, ADInstruments, Colorado Springs, CO, USA).

All potential subjects will receive a continuous glucose sensor at Visit 1. At the following visits, the CGM will be reviewed for hypoglycaemia episodes and replaced at the same time. At Visit 2 a final screening of the inclusion criteria will take place, which involves the CGM data of the first week. A CGM will be installed a week before every visit.

Estimating resting metabolic rate, before and during hyperinsulinemic-hypoglycemic clamp

Estimating skin temperature, before and during hyperinsulinemic-hypoglycemic clamp

Plasma lactate during glucagon injections.

Plasma free fatty acids during glucagon injections.

Plasma glycerol during glucagon injections.

Plasma alanine during glucagon injections.

Plasma β-hydroxybutyrate during glucagon injections.

Plasma insulin during glucagon injections.

Plasma glucagon during glucagon injections.

Plasma metabolomics during glucagon injections.

Plasma lactate during epinephrine infusion

Plasma free fatty acids during epinephrine infusion

Plasma glycerol during epinephrine infusion

Plasma alanine during epinephrine infusion

Plasma β-hydroxybutyrate during epinephrine infusion

Plasma insulin during epinephrine infusion

Plasma glucagon during epinephrine infusion

Plasma catecholamines during epinephrine infusion

Plasma catecholamines during epinephrine infusion

Plasma metabolomics during epinephrine infusion

Personality traits using the psychometry questionnaire DS-14, score between 0-28, the higher, the more likely they have type D personality

Personality traits using the psychometry questionnaire TAS-20, score 20-100, the higher score the more likely they are alexithymia

Diabetes and hypoglycaemia status using psychometry questionnaire HFS-W, score 0-72, the higher score the higher fear for hypoglycemia

Diabetes and hypoglycaemia status using psychometry questionnaire HABS, score from 14-45, higher score more fear of hypoglycemia

Diabetes and hypoglycaemia status using psychometry questionnaire PAID, 0-80, the higher score, the more problems with diabetes

Using Food Frequency Questionnaire to analyze food consumption

Using hypoglycemia awareness status questionnaire

, 0-7, higher score indicate hypoglycemia unawareness