To Define the Role of GLP-1 for Improving Glucose Homeostasis in Humans Following Gastric Bypass Surgery

You may not qualify if:

• Lacks cognitive ability to sign the consent \&/or follow the study directions for themselves.
• Women unwilling to comply with using an acceptable method of contraception during the course of the study, or who are currently breast-feeding.
• Volunteers with a history of Acute Pancreatitis.
• Volunteers with a history of cancer (except for skin cancer).
• Volunteer with a history of Chronic Pancreatitis and/or risk factors for chronic pancreatitis including hypertriglyceridemia (triglycerides \>400mg/ml) hypercalcemia (blood calcium level \>11.md/dl) and/or the presence of gallstones.
• Subjects taking medications known to affect glucose tolerance.
• Hematocrit from the lab is below 33% (or if the finger stick hemoglobin measured with the HemoCue 201+ is \<11.2 g/dl).
• Any major medical conditions, or conditions that in the opinion of the PI make the subject unsuitable for the study.
• Subjects with abnormal kidney function as measured by the Creatinine concentration will be excluded.
• Subjects with a history of active liver disease or AST/ALT levels \>2X upper limit of normal will also be excluded.
• Total Bilirubin levels should be \<2.
• Subjects unwilling to allow the use of their own blood or albumin in the preparation of the peptides. (The blood will prevent sticking of the peptide to the tubing; an alternative method has been sought but not found.)
• Unwillingness to return have 8-10ml of blood drawn 25-30 days after the last Xenin infusion; to check for Xenin peptide antibodies that MAY develop. (All efforts will be made to complete this visit during study participation.)