Adrenal Gland Function
The cortex and medulla of the adrenal glands perform different functions. The hormones released by the cortex regulate the body's metabolic rate, maintain a balance of minerals, maintain blood pressure and also aid the immune system. Following are the main hormones released by the cortex:
Aldosterone belongs to the class of mineralocorticoids, hormones responsible for maintaining the balance of salt and water in the body. Therefore, aldosterone is mainly responsible for the regulation of blood pressure. It affects the kidneys to control the amount of minerals reabsorbed into the blood during the formation of urine.
Cortisol is a glucocorticoid hormone and is responsible for the metabolism of glucose and other carbohydrates, as well as fats and proteins. It is also known as hydrocortisone hormone.
Corticosterone is another glucocorticoid. It works along with cortisol to aid the immune system of the body. It also fights inflammation.
The main androgenic hormone released by the cortex is androstenedione which is a precursor for testosterone. The latter plays a significant role in the development of secondary male sexual characteristics.
The hormones released by the medulla are discussed below.
It is also known as epinephrine and is released in response to stress, danger or excitement. Adrenaline produces a set of effects which prepare the body for “fight or flight”. The blood glucose level increases in order to make the source of energy readily available for the body. Moreover, the heart beat increases so that blood can be pumped faster throughout the body, providing oxygen and other nutrients, especially to the muscles.
It is also known as norepinephrine. It causes vascontriction of the blood vessels, leading to a high blood pressure. Norepinephrine also acts under stress conditions along with epinephrine to prepare the body for situations of fright or danger. It is a hormone which also acts as a neurotransmitter and affects the heart rate.