15.10A: Overview of the Adrenal Glands

Last updated
Save as PDF

Page ID: 7772

\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\)

In mammals, the adrenal glands (also known as the suprarenal glands) are endocrine glands that sit atop the kidneys.

Learning Objectives

Describe the location and function of the adrenal glands

Key Points

The adrenal glands are are endocrine glands located atop the kidneys.
They are responsible for releasing three classes of hormones;
mineralocorticoids, glucocorticoids, and androgens along with
catecholamines.
Each adrenal gland is composed to two structures: the adrenal medulla and adrenal cortex.

Key Terms

adrenal cortex: The outer portion of the adrenal glands that produces
mineralocorticoids, glucocorticoids, and androgens.
Adrenal medulla: The innermost part of the adrenal gland, consisting of cells that secrete adrenaline and noradrenaline.

In mammals, the adrenal glands (also known as the suprarenal glands) are endocrine glands that sit atop the kidneys. They are chiefly responsible for releasing three classes of hormones:

Mineralocorticoids (aldosterone)
Glucocorticoids (cortisol)
Androgens (DHEA)

This is an illustration of the adrenal glands. They are triangular-shaped organs on top of the kidneys.

Adrenal glands: The adrenal glands are triangular-shaped organs on top of the kidneys.

Along with catecholamines (adrenaline), these hormones control a variety of functions including kidney function, metabolism, fight-or-flight response, and sex hormone levels.

In humans, the adrenal glands are found at the level of the 12th thoracic vertebra sitting above and slightly medial to the kidneys, lying within the renal fascia, and separated from the kidneys by a thin layer of connective tissue. In humans, the right adrenal gland is triangular shaped, while the left adrenal gland is semilunar shaped.

Each adrenal gland has two distinct structures, the outer adrenal cortex and the inner medulla—both produce hormones. The cortex mainly produces mineralcorticoids, glucocorticoids, and androgens, while the medulla chiefly produces adrenaline and nor-adrenaline.