Epinephrine is one of the important hormones in the defense of hypoglycemia. We will test the hypothesis that antecedent hypoglycemia will blunt the metabolic, neuroendocrine and cardiovascular effects of subsequent epinephrine infusion in Type 1 DM.

When a person had previously experienced bouts of low blood sugar, or hypoglycemia, his or her counterregulatory responses to hypoglycemia would be weakened. This is especially true and important for a person with Type 1 diabetes, because it will cause him or her to be vulnerable to another bout of hypoglycemia, and cause hypoglycemia unawareness, which can lead to serious or even life-threatening consequences. Epinephrine is one of the important hormones in the defense of hypoglycemia. We will test the hypothesis that antecedent hypoglycemia will blunt the metabolic, neuroendocrine and cardiovascular effects of subsequent epinephrine infusion in Type 1 DM.

Inclusion Criteria:

• 28 (14 males, 14 females) conventionally treated Type 1 diabetic patients with HA1C > 8.5%
• 28 (14 males, 14 females) intensively treated Type 1 diabetic patients with HA1C < 7%
• 28 (14 males, 14 females) non-diabetic controls
• Age 18-45 yr.
• Had diabetes for 2-15 years if diabetic subject
• No clinical evidence of diabetic tissue complications, no cardiovascular disease
• Body mass index 21-27kg · m-2
• Normal bedside autonomic function
• Normal results of routine blood test to screen for hepatic, renal, and hematological abnormalities
• Female volunteers of childbearing potential: negative HCG pregnancy test

Exclusion Criteria:

• Prior history of poor health: any current or prior disease condition that alters carbohydrate metabolism and prior cardiac events and/or evidence for cardiac disease
• Hemoglobin of less than 12 g/dl
• Abnormal results following screening tests
• Pregnancy
• Subjects unable to give voluntary informed consent
• Subjects with a recent medical illness
• Subjects with known liver or kidney disease
• Subjects taking steroids
• Subjects taking beta blockers
• Subjects on anticoagulant drugs, anemic, or with known bleeding diseases