Effects of Glucagon and Tolbutamide on Plasma Insulin Levels in Children with Ketoacidosis

The concentration of immunoreactive insulin in plasma has been determined following administration of tolbutamide and glucagon in seven children with newly diagnosed diabetic ketoacidosis. The basal plasma insulin levels were low, notwithstanding concomitantly high blood glucose levels. The plasma insulin concentration was increased by glucagon but not tolbutamide stimulation. These data suggest that a different mechanism of insulin release is induced by tolbutamide and glucagon.