Effect of Glucagon on Plasma Amino Acid and Glucose Levels in a Patient Who Had Undergone Total Pancreatectomy

The plasma glucose and amino acid levels of a patient who had undergone total gastrectomy and total pancreatectomy 15 years previously were examined under 4 conditions determined by the method of exogenous glucagon injection. Glucagon was not injected in the first period, and 1mg of glucagon was injected twice a day in the second period. Twice a day 1mg of zinc glucagon was injected in the third period, and 2mg/day of glucagon by continuous subcutaneous glucagon infusion (CSGI) was given in the fourth period. The plasma pancreatic glucagon levels were within the normal range during CSGI. The effect of glucagon on plasma amino acid levels was greatest with CSGI. The effect became less in the order of zinc glucagon injection and twice-a-day injection of 1mg of glucagon. Furthermore, afternoon hyperglycemia and nocturnal hypoglycemia were suppressed with CSGI. Urinary nitrogen excretion was increased with glucagon injection. However, excretion of 3-methylhistidine did not show any significant increase. From these results we consider that exogenous glucagon injection has significant effects on the metabolism of glucose and amino acids after total pancreatectomy. We also conclude that both continuous subcutaneous glucagon infusion and zinc glucagon are useful in the postoperative management of total pancreatectomy