Which zona of the adrenal cortex is concerned with carbohydrate metabolism?

The zona fasciculata is the layer of the adrenal cortex primarily responsible for carbohydrate metabolism. This region synthesizes and secretes glucocorticoids, predominantly cortisol, which plays a crucial role in regulating glucose metabolism. Cortisol facilitates gluconeogenesis, the process by which glucose is produced from non-carbohydrate substrates in the liver, thus increasing blood sugar levels. This is particularly important during stress or fasting when the body requires additional energy sources.

Moreover, cortisol influences how the body responds to insulin and contributes to maintaining proper blood sugar levels. The action of the zona fasciculata is essential for various metabolic processes, including fat and protein metabolism, further emphasizing its importance in overall energy management.

In contrast, the zona glomerulosa primarily produces mineralocorticoids like aldosterone, which regulate electrolyte and fluid balance. The zona reticulata mainly secretes androgens, which are involved in the development of secondary sexual characteristics. The adrenal medulla, while a critical part of the adrenal gland, is responsible for producing catecholamines like adrenaline, which are pivotal in the body's fight-or-flight response rather than directly influencing carbohydrate metabolism.