Gastrointestinal Sensorimotor Dysfunctions in Diabetes Mellitus

Inclusion criteria for controls:

• Healthy male or non-pregnant, non-breastfeeding female volunteers;
• 18-70 years old;
• Able to provide written informed consent before participating in the study;
• Able to communicate adequately with the investigator and to comply with the requirements for the entire study

Additional inclusion criteria for patients:

• Symptoms of dyspepsia (i.e., early satiety, postprandial discomfort, nausea, vomiting, regurgitation)
• Patients in the Diabetes Mellitus (DM) group will also require Type 1 or 2 DM of ≥ 3 years duration; in patients with type 2 DM, the dyspepsia symptoms should have begun or worsened after DM was diagnosed

Exclusion criteria - for patients and controls:

• Major abdominal surgery (i.e., appendectomy, cholecystectomy, tubal ligation, hysterectomy, and limited colonic resection are permissible)
• Clinical evidence (including physical exam and EKG) of significant cardiovascular, respiratory, renal, hepatic, gastrointestinal, hematological, neurological, psychiatric or other disease that may interfere with the objectives of the study and/or pose safety concerns
• Opiates, alpha adrenergic agonists, metoclopramide, and high doses of anticholinergic agents (e.g., amitriptyline greater than 50 mg daily). If medically safe, these drugs may be discontinued for four half lives prior to study assessments
• Treatment with glucagon-like peptide-1 (GLP-1) agonists and amylin which cause vagal blockade and may affect central processing of pain
• Use of tobacco products within the past six months or NSAIDs or aspirin within the past week (since they all may affect intestinal permeability)
• Bleeding or clotting disorders or medications that increase risk of bleeding from mucosal biopsies
• Positive tissue transglutaminase antibodies (TTG)
• For two days prior to studies, subjects will be instructed to avoid ingestion of artificial sweeteners such as sucralose (SplendaTM), aspartame (NutrasweetTM), foods containing lactulose or mannitol
• Pregnant or breast-feeding females
• Known intolerance or allergy to eggs
• Poor peripheral venous access, if central venous access is not available
• Any other condition or prior therapy that, in the opinion of the investigator, would make the patient unsuitable for the study

Exclusion criteria for controls only:

• Current symptoms of a functional gastrointestinal disorder assessed by questionnaire

Exclusion criteria for patients only:

• Severe vomiting that would preclude tube placement or participation in the study
• Structural cause for symptoms by endoscopy within the past 48 months
• Patients with gastric pacemakers