Effect of Theophylline, Glucagon and Theophylline plus Glucagon on Insulin Secretion in the Premature Infant

Serum insulin was measured in thirty premature infants in the first twenty-four hours of life following the administration of theophylline, glucagon, or theophylline plus glucagon. Theophylline (1 mg. per min.) produced a striking rise in serum insulin without change in blood glucose. Neither glucagon (0.4 γ per min.) nor theophylline (0.5 mg. per min.) produced any significant change in the levels of blood glucose and serum insulin. However, the simultaneous administration of these doses of glucagon and theophylline was followed by a progressive rise in blood glucose and serum insulin. The insulin secretion with this combination exceeded that seen with a rapid injection of 300 γ of glucagon.