The adrenal gland consists of an outer cortex of glandular tissue and an inner medulla of nervous tissue. (Image credit: 'The Adrenal Glands' by Julie Jenks is licensed under CC BY 4.0 / A derivative from the original work / Micrograph provided by the Regents of University of Michigan Medical School © 2012) The adrenal medulla releases stress hormones such as epinephrine and norepinephrine that stimulate the sympathetic autonomic nervous system (ANS).
The cortex can be subdivided into additional zones listed from superficial to deep: the zona glomerulosa that releases mineralocorticoids such as aldosterone to regulate mineral balance, the zona fasciculata that releases glucocorticoids such as cortisol, corticosterone, and cortisone to regulate glucose metabolism, and the zona reticularis that releases androgens such as dehydroepiandrosterone that stimulate masculinization.
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.
