Changes in plasma level of corticotropin after intravenous injection of metyrapone. Value of this test in pituitary pathology

: The Metyrapone was given, the morning, in perfusion intravenous of saline serum over 2 hours. A.C.T.H. levels were determined before and at 2, 4, 8 and 24 hours. Sixteen normal subjects adults served on controls with 1 g of Metyrapone. Sixteen other normal subjects with 2 g of Metyrapone are best responses. With this maximum dose 2 g were studied nine hypophysal adenomas with three low responses, three normal and three high responses; thirteen hypophysectomised subjects with very low peak value at 4 hours, and only two responses higher than the controls, five Cushing's syndromes with variable responses. The I.V. Metyrapone test seems to offer several advantages: it eliminates the questions about gastro-intestinal absorption of Metyrapone (oral) and the difficulties of urine collection. With the A.C.T.H. dosage on 4 hours, this is a rapid test able to put in combination other hypophysal tests.