Partial Somatotrophin Insufficiency in Cushing's Syndrome

Plasma growth hormone levels were studied in 15 patients with Cushing's syndrome using several stimuli. All tests except one, were performed before treatment. No change occurred in 6 patients during acute hypoglycaemia and in 11 out of 13 after a glucose load. Arginine given intravenously to 11 subjects elicited a rise in 7 out of 8 females and 1 out of 3 males. From patients who responded to arginine infusion, 6 were insensitive to one or two of the above mentioned stimuli. A selective inhibition of the releasing mechanisms might account for the partial somatotrophin insufficiency found in Cushing's syndrome.