Inclusion Criteria:

• Age 18-50 years
• BMI 19-30 kg/m2
• Creatinine ≤ 1.5 mg/dl
• No hypoglycemia unawareness by clinical history
• current non-smoker
• alcohol consumption <5 g/week
• for women of child bearing potential, negative pregnancy test
• no eating disorder
• no current substance abuse
• HbA1c ≤ 9% in T1DM subjects and < 5.7% in healthy nondiabetic subjects.
• normal fasting glucose (70-99 mg/dl) in healthy subjects
• On insulin pump therapy for at least six months for T1DM subjects
• no symptomatic gastroparesis
• no unstable retinopathy (requiring photocoagulation within past 6 months)

Exclusion Criteria:

• Admission for diabetic ketoacidosis in the 12 months prior to enrollment
• Severe hypoglycemia resulting in seizure or loss of consciousness in the 12 months prior to enrollment
• History of a seizure disorder (except hypoglycemic seizure), unless written clearance is received from a neurologist
• Coronary artery disease or heart failure.
• History of cardiac arrhythmia (except for benign premature atrial contractions and benign premature ventricular contractions which are permitted)
• Cystic fibrosis
• A known medical condition that in the judgment of the investigator might interfere with the completion of the protocol such as the following examples:
  • Inpatient psychiatric treatment in the past 6 months
  • Presence of a known adrenal disorder
  • Abnormal liver function test results (Transaminase >2 times the upper limit of normal);
  • Abnormal renal function test results (creatinine > 1.5 mg/dl);
  • Active gastroparesis or on medications for gastroparesis
  • If on antihypertensive, thyroid, anti-depressant or lipid lowering medication, lack of stability on the medication for the past 2 months prior to enrollment in the study
  • Uncontrolled thyroid disease (TSH undetectable or >10 mlU/L)
  • Abuse of alcohol or recreational drugs
• Current use of the following drugs and supplements:
  • Any medication other than insulin, being taken to lower blood glucose, such as Pramlintide, Metformin, GLP-1 Analogs such as Liraglutide, and nutraceuticals intended to lower blood glucose
  • Oral or injectable glucocorticoids
  • Any other medication that the investigator believes is a contraindication to the subject’s participation