[Anomalies of corticotropin secretion in chromophobe adenomas]

Corticotrophic secretion has been studied in several groups of subjects during metopirone test and arginine L-Dopa infusion. In animals, a net plasma ACTH increase is observed under while it is inconstant after arginine L-Dopa. In hypopituitarism, metopirone ACTH levels are low and unchanged during the tests. In chromophobe adenoma, basal ACTH levels are high, ACTH increase is normal during test and significantly higher than in controls after L-Dopa injection. Significance of these metopirone corticotrophic abnormalities is discussed.