Anatomical and Physiological Characterisation of the Gut Endocrine Cells in Healthy and in Patients With Type 2 Diabetes

Inclusion criteria: Type 2 diabetes patients * Diagnosis of type 2 diabetes (at least 3 months prior to study inclusion) * Treatment with diet counseling alone or combined with an glucose-lowering drugs: metformin or sulphonylurea * Caucasian ethnicity * Age \>25 and \<70 years * Normal hemoglobin * Negative for autoantibodies to glutamic acid decarboxylase (GAD-65) and islet cell autoantibodies (ICA). Healthy individuals * Fasting plasma glucose \<6.0 mM * Plasma glucose 2 hours after a 75 g-oral glucose tolerance test \<7.8 mM * Negative for GAD-65 antibodies and ICA * Caucasian ethnicity * Age \>25 and \<70 years * Normal hemoglobin Exclusion criteria: Type 2 diabetes patients * Liver disease (evaluated by alanine aminotransferase and/or aspartate aminotransferase \>2 times normal value) * Treatment with dipeptidyl peptidase 4 inhibitors or medicine that could not be paused for 12 hours * Previous hysterectomy, appendectomy, cholecystectomy or caesarean * Sleep apnea * American Society of Anesthesiologists class \>3 * Allergy to soy protein or eggs * BMI \>35 kg/m2 or any other condition that would contraindicate propofol sedation or enteroscopy. Healthy individuals * Liver disease (evaluated by alanine aminotransferase and/or aspartate aminotransferase \>2 times normal value) * Liver disease (evaluated by alanine aminotransferase and/or aspartate aminotransferase \>2 times normal value) * Treatment with dipeptidyl peptidase 4 inhibitors or medicine that could not be paused for 12 hours * Previous hysterectomy, appendectomy, cholecystectomy or caesarean * Sleep apnea * American Society of Anesthesiologists class \>3 * Allergy to soy protein or eggs * BMI \>35 kg/m2 or any other condition that would contraindicate propofol sedation or enteroscopy * First-degree relative(s) with type 1 or type 2 diabetes.