Cortisol and the adrenal androgens are derived from the fasciculata and reticularis cells. The only known important control mechanism is by means of ACTH (Fig. 7.3). This anterior pituitary hormone regulates adrenocortical growth; it also mediates the rate at which steroid biosynthesis occurs. Other fragments of the ACTH precursor, pro-opiomelanocortin (POMC), may also have a trophic effect on the adrenal, and antidiuretic hormone (ADH/vasopressin) may act synergistically with ACTH to stimulate steroid biosynthesis.
