nadnercza

Adrenal glands (nadnercza) are small endocrine glands located on the superior poles of the kidneys. Each gland comprises two structurally and functionally distinct regions: the outer cortex and the inner medulla.

The cortex, derived from mesoderm, secretes steroid hormones in three zones. The zona glomerulosa produces mineralocorticoids, principally aldosterone, which regulate sodium and potassium balance and influence blood pressure. The zona fasciculata releases glucocorticoids, mainly cortisol, important for glucose metabolism, immune modulation, and the stress response. The zona reticularis produces androgens such as dehydroepiandrosterone (DHEA). Cortical hormone release is regulated by adrenocorticotropic hormone (ACTH) from the pituitary, with aldosterone also controlled by the renin–angiotensin system and plasma potassium.

The medulla, derived from neural crest cells, contains chromaffin cells that secrete catecholamines—epinephrine and norepinephrine—in response to sympathetic activity. These hormones prepare the body for acute stress by increasing heart rate, blood pressure, and energy availability.

Regulation and physiology: the adrenal glands interact with the autonomic nervous system and endocrine systems to maintain fluid balance, metabolism, and cardiovascular responses. Disorders include Addison’s disease (adrenal insufficiency), Cushing’s syndrome (excess cortisol), primary hyperaldosteronism (excess aldosterone), and pheochromocytoma (catecholamine-secreting tumor).

Development and vasculature: the cortex arises from mesoderm; the medulla from neural crest. The glands receive arterial blood from superior, middle, and inferior suprarenal arteries, and drain via the suprarenal veins into the renal veins or inferior vena cava.