Adrenale

Adrenale is a term used in medical contexts to refer to the adrenal glands, the paired endocrine organs situated on top of the kidneys in the retroperitoneal space. In English, the glands are usually called the adrenal glands or the suprarenal glands. The form adrenale may appear as an adjective describing properties or conditions related to these glands in several languages.

Anatomy and structure

Each adrenal gland has two structurally and functionally distinct regions: the cortex on the outside and the medulla on the inside. The cortex is subdivided into zones that synthesize different classes of steroids, while the medulla produces catecholamines. The glands receive rich blood supply from multiple suprarenal arteries and drain into the systemic venous system.

Hormones and functions

The adrenal cortex secretes mineralocorticoids (principally aldosterone), glucocorticoids (principally cortisol), and adrenal androgens. These hormones regulate salt and water balance, metabolism, stress response, immune function, and sexual development. The adrenal medulla produces catecholamines, especially epinephrine and norepinephrine, which mediate the fight-or-flight response by increasing heart rate, blood pressure, and glucose availability.

Regulation and clinical relevance

Adrenal hormone production is controlled by distinct regulatory pathways: the hypothalamic-pituitary-adrenal axis primarily influences cortisol via ACTH, while the renin-angiotensin-aldosterone system regulates aldosterone. Clinical conditions include adrenal insufficiency (e.g., Addison’s disease), Cushing syndrome from excess cortisol, primary hyperaldosteronism, and pheochromocytoma, a tumor causing excess catecholamines. Adrenal incidentalomas are masses discovered incidentally during imaging.

Development and variation

The cortex derives from mesoderm, the medulla from neural crest cells. Function and size can vary among individuals and across species, but the basic zonation and hormonal roles are broadly conserved in mammals.