Effect of Propranolol on the Response of Serum Growth Hormone to Glucagon

In normal subjects the response of serum growth hormone to the intramuscular or subcutaneous injection of glucagon was augmented by a single oral dose of propranolol (40 mg) given 2 hours before injection. In addition, propranolol induced a normal response of serum growth hormone to glucagon in the few normal persons failing to respond to glucagon alone. Although approximately 90% of normal persons respond to glucagon alone with a rise in serum growth hormone, oral propranolol increases the percentage and thus enhances the value of the glucagon stimulation test in detecting a deficiency of growth hormone. This conclusion is reinforced by the lack of response in hypopituitarism and the conversion of a poor to a normal response in 1 of 2 patients with primary hypothyroidism when propranolol was added to the glucagon stimulation test.