- We will recruit normal weight (BMI 19 to 25 kg/m2), glucose tolerant, healthy volunteers, who are between the ages of 20 and 45 years old. Volunteers for this study must have a fasting glucose < 100 mg/dl; HbA1c < 6.0; Hct > 34; ALT < 60; AST < 60; Alk phos < 150; TSH < 8; Trig < 300; Chol < 250; systolic BP < 150; diastolic BP < 95; negative family history (first-degree relatives) for type 2 DM; be in good health and not be taking any chronic medications. Previous difficulty with xylocaine will be an exclusion. To be eligible for these studies, volunteers must be free of clinical evidence of cardiac, renal, hepatic, and vascular disease, or other major medical problems that would endanger the volunteers or compromise the scientific validity of the studies. Subjects with a history of myocardial infarction, proteinuria (defined as 1+ protein), liver disease, alcohol or drug abuse, malignancy or neuromuscular disease will be excluded.