[Pathways of corticosteroid biosynthesis in human adrenals (Itsenko-Cushing disease)]

Pregnenolone and its hydroxyl derivatives are of dominant importance in cortisol and corticosterone synthesis in human adrenals (hyperplasic glands and adenomes) removed in Itsenko-Kushing disease. Progesterone is produced in minimal amounts and is nearly not used for steroidogenesis. Participation of 17,21-dihydroxypregnenolone in cortisol synthesis is demonstrated. 17-hydroxyprogesterone is found not to take an important part as cortisol precursor. 21-hydroxypregnenolone is an essential intermediate in corticosterone synthesis. 11-hydroxyprogesterone does not participate in corticosteroids formation, since the rate of progesterone 11-hydroxylation in human adrenal mitochondria is minimal.