lisämunuaiskorteksin

Lisämunuaiskorteksi, also known as the adrenal cortex, is the outer layer of the adrenal gland. It is composed of three distinct zones, each producing different steroid hormones. The outermost zone is the zona glomerulosa, which primarily synthesizes mineralocorticoids, the most important of which is aldosterone. Aldosterone plays a crucial role in regulating blood pressure and electrolyte balance by promoting sodium reabsorption and potassium excretion in the kidneys.

Beneath the zona glomerulosa lies the zona fasciculata, the thickest layer of the adrenal cortex. This zone produces glucocorticoids, with cortisol being the main representative. Glucocorticoids have widespread effects on the body, including regulating metabolism, suppressing the immune system, and responding to stress. They influence glucose, protein, and fat metabolism, increasing blood glucose levels and affecting the distribution of body fat.

The innermost layer of the adrenal cortex is the zona reticularis. This zone synthesizes androgens, such as dehydroepiandrosterone (DHEA) and androstenedione. These hormones are weak sex hormones and are converted into more potent androgens and estrogens in other tissues. In women, they contribute to the development of secondary sexual characteristics. The production of these hormones is stimulated by adrenocorticotropic hormone (ACTH) from the pituitary gland, although the zona glomerulosa's production of aldosterone is primarily regulated by the renin-angiotensin-aldosterone system.