Iatrogenic hypoglycemia is the most prominent barrier to the safe, effective management of blood sugar in people with type 1 diabetes due to periodic over-insulinization. During insulin-induced hypoglycemia, glucagon secretion is diminished in type 1 diabetes which, in turn, reduces hepatic glucose production and increases the depth and duration of hypoglycemic episodes. We have observed that the naturally occurring protein C-peptide increases glucagon secretion in dogs during insulin-induced hypoglycemia, which increases hepatic glucose production; the experiments in this application will shed light on the translation of this finding to the human.