Each region secretes its own set of hormones. The cortex itself is divided into three zones: the zona glomerulosa, the zona fasciculata, and the zona reticularis. The adrenal gland consists of an outer cortex of glandular tissue and an inner medulla of nervous tissue. (Micrograph provided by the Regents of University of Michigan Medical School © 2012). The cortex can be subdivided into additional zones, all of which produce different types of hormones. Both adrenal glands sit atop the kidneys and are composed of an outer cortex and an inner medulla, all surrounded by a connective tissue capsule. Adrenal hormones are released into the circulation via the left and right suprarenal veins. Blood flows to each adrenal gland at the adrenal cortex and then drains into the adrenal medulla. They are served by several arteries branching off the aorta, including the suprarenal and renal arteries. The adrenal glands have a rich blood supply and experience one of the highest rates of blood flow in the body.
The adrenal glands are wedges of glandular and neuroendocrine tissue adhering to the top of the kidneys by a fibrous capsule (Figure 14.6.1).
Identify the hormones produced by the adrenal cortex and adrenal medulla and summarise their target cells and effects.
By the end of this section, you will be able to:
