The Effect of Oxytocin on the Alpha Cell Response to Hypoglycaemia in Patients With Type 1 Diabetes

Inclusion Criteria: * Body mass index from 19 to 30 kg/m2 * T1D (diagnosed according to the criteria of the World Health Organization) with HbA1c \<69 mmol/mol (\<8.5%) * T1D duration of 3-30 years * C-peptide negative (stimulated C-peptide ≤ 100 pmol/l) * Treatment with a stable basal-bolus or insulin pump regimen for ≥3 months Exclusion Criteria: * Anaemia (haemoglobin below normal range) * Liver disease (alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) \>2 times normal values) or present hepatobiliary and/or gastrointestinal disorder(s) * Kidney disease (serum creatinine above normal range) * Late microvascular complications except mild non-proliferative retinopathy * Regular tobacco smoking or use of other nicotine-containing products * Long QTc on electrocardiogram (ECG) at screening (≥0.45 seconds) * Pituitary gland disease * Treatment with any glucose-lowering drugs besides insulin * Any ongoing medication or physical or psychological condition that the investigator feels would interfere with trial participation