Adrenaalnäärmed

Adrenaalnäärmed, also known as suprarenal glands, are endocrine glands in humans and other mammals. They are located on top of the kidneys, hence the name "suprarenal" which means "above the kidney". Each adrenal gland is composed of two distinct parts: the outer cortex and the inner medulla.

The adrenal cortex is responsible for producing steroid hormones. It is further divided into three zones, each secreting different hormones. The outermost zone, the zona glomerulosa, produces mineralocorticoids, primarily aldosterone, which regulates electrolyte balance, particularly sodium and potassium, and blood pressure. The middle zone, the zona fasciculata, produces glucocorticoids, most notably cortisol. Cortisol plays a crucial role in stress response, metabolism, immune function, and inflammation. The innermost zone, the zona reticularis, synthesizes androgens, which are sex hormones that can influence secondary sexual characteristics.

The adrenal medulla, the inner part of the gland, produces catecholamines, mainly adrenaline (epinephrine) and noradrenaline (norepinephrine). These hormones are vital for the body's "fight-or-flight" response, increasing heart rate, blood pressure, and energy supply during times of stress or excitement. The adrenal glands are essential for maintaining homeostasis and responding to various physiological challenges. Disorders affecting the adrenal glands can lead to conditions such as Cushing's syndrome, Addison's disease, and pheochromocytoma, each with distinct hormonal imbalances and clinical manifestations.