ABSTRACT
The adrenal glands are paired retroperitoneal organs which lie superomedial to each kidney with the right adrenal gland positioned more cephaloposterior as compared to the position the left adrenal. Each gland consists of an outer cortex and an embryologically, histologically, and functionally distinct inner medulla. The adrenal cortex can be considered as an amalgamation of two organs, a subcapsular zona glomerulosa, which synthesizes mineralocorticoids, principally aldosterone, under the control of the reninangiotensin system, and a deeper zona fasciculata and reticularis that secrete glucocorticoids, principally cortisol and
the weak androgens dehydroepiandrosterone (DHEA), its sulfate (DHEA-S), and androstenedione, and estrogens under the control of adrenocorticotrophic hormone (ACTH) (Fig. 12C.1). The adrenal medulla shares its neural crest origin with the sympathetic ganglia, paraganglia, and other adrenergic tissues. Like those organs, it synthesizes and stores noradrenaline (norepinephrine), but its ability to convert noradrenaline to adrenaline (epinephrine) is unique.
