What does the zona glomerulosa primarily produce?

The zona glomerulosa is the outermost layer of the adrenal cortex and is primarily responsible for the production of mineralocorticoids, with aldosterone being the most significant hormone produced in this region. Mineralocorticoids play a crucial role in regulating electrolyte and fluid balance in the body, particularly by promoting sodium reabsorption in the kidneys, which also helps control blood pressure. This regulatory function is vital for maintaining homeostasis, and aldosterone's actions can influence the retention of water and excretion of potassium.

In contrast, the inner layers of the adrenal cortex, such as the zona fasciculata, produce glucocorticoids like cortisol, while the zona reticularis produces androgens or sex hormones. Catecholamines, such as adrenaline and norepinephrine, are produced by the adrenal medulla, not the cortex. Thus, the primary output of the zona glomerulosa is accurately identified as mineralocorticoids.