Cortisol

Cortisol is a steroid hormone, in the glucocorticoid class of hormones, and is produced in humans by the zona fasciculata of the adrenal cortex within the adrenal gland. It is released in response to stress and low blood-glucose concentration.

It functions to increase blood sugar through gluconeogenesis, to suppress the immune system, and to aid in the metabolism of fat, protein, and carbohydrates. It also decreases bone formation.

Hydrocortisone (INN, USAN, BAN) is a name for cortisol when it is used as a medication. Hydrocortisone is used to treat people who lack adequate naturally generated cortisol. It is on the World Health Organization's List of Essential Medicines needed in a basic health system.

Health effects

Metabolic response

In the early fasting state, cortisol stimulates gluconeogenesis (the formation of glucose), and activates anti-stress and anti-inflammatory pathways. Cortisol also plays an important, but indirect, role in liver and muscle glycogenolysis, the breaking down of glycogen to glucose-1-phosphate and glucose. This is done through its passive influence on glucagon. Additionally, cortisol facilitates the activation of glycogen phosphorylase, which is necessary for epinephrine to have an effect on glycogenolysis.