The adrenal cortex, as a component of the hypothalamic-pituitary-adrenal (HPA) axis, secretes steroid hormones important for the regulation of the long-term stress response, blood pressure and blood volume, nutrient uptake and storage, fluid and electrolyte balance, and inflammation. 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.
