Adrenal Glands: What to Know

Your body is made up of many different systems working together. One of those is the endocrine system, the system in your body that is responsible for hormone production and release. The adrenal glands are an essential part of this system.

What Are the Adrenal Glands?

Your adrenal glands are a pair of small, triangular glands that act as a part of your endocrine system. The endocrine system is a network of glands and organs within your body that make and release hormones. Hormones are chemicals that initiate and sustain functions all over your body. 

Aside from the adrenal glands, the endocrine system also includes the:

• Hypothalamus. The hypothalamus is located within the brain and controls the endocrine system.
• Ovaries. Ovaries are typically found in those assigned female at birth. The two ovaries release estrogen, progesterone, and testosterone. 
• Pancreas. The pancreas makes insulin, which controls your blood sugar levels. 
• Parathyroid. Your body has four parathyroid glands, and they’re tiny, roughly the size of grains of rice. They control how much calcium is in your body.
• Pineal gland. The pineal gland is located within the brain. It controls your sleep cycle by releasing melatonin.
• Pituitary gland. The pituitary gland is a small, pea-sized gland at the base of your brain. It makes several hormones that your body needs.
• Testes. Testes are typically found in those assigned male at birth. Their job is to release testosterone, as well as to make sperm.
• Thyroid. The butterfly-shaped thyroid gland is located at the front of your neck. It controls your metabolism. 

Where Are the Adrenal Glands Located?

You have two adrenal glands. One sits on top of each of your kidneys like little triangular hats. From this position, your adrenal glands receive instructions, then produce and release hormones.

What Do the Adrenal Glands Do?

The adrenal glands, like other parts of the endocrine system, make and release hormones. The adrenal glands’ hormones can be divided into two groups: catecholamines and steroid hormones.

Catecholamines. Catecholamines are the hormones that your body releases when you’re in a stressful situation. These hormones are made by the inner part of your adrenal glands, which are called the adrenal medulla. 

The catecholamines that your adrenal medulla release include:

• Adrenaline. Also called epinephrine, the hormone adrenaline activates your body’s “fight or flight” response. When your brain senses danger, it produces adrenaline that encourages your body to make changes like dilating your pupils, increasing your blood flow, and breathing faster. Adrenaline also has many uses in medicine. It can be used to open the airways of asthma patients or those who are having an allergic reaction.
• Noradrenaline. Also called norepinephrine, noradrenaline works alongside adrenaline to activate the fight or flight response. Its primary job is to increase and manage blood pressure. Noradrenaline also has several uses as a medication. It’s used to elevate blood pressure in the short term or in emergency situations. These situations may include overdoses, blood transfusions, septic shock, and heart attacks. 

Steroid hormones. Steroid hormones play a part in many bodily functions, including the immune response, metabolism, the balance of salt and water within your body, and the development of sex characteristics. These hormones are made in the outer part of the adrenal glands, which is called the adrenal cortex. 

The steroid hormones that the adrenal cortex makes include:

• Aldosterone. The job of aldosterone in the body is to regulate your blood pressure and levels of the electrolytes potassium and sodium in your blood. As a result, aldosterone helps regulate your blood’s pH. Aldosterone is made in a section of the adrenal cortex called the zona glomerulosa.
• Cortisol. The hormone cortisol has many jobs and affects many different systems of your body. It plays a role in controlling your sleep-wake cycle, controlling metabolism, regulating blood pressure and blood sugar levels, and reducing inflammation. Cortisol is sometimes called the “stress hormone” because it activates when you’re feeling stress to help your body manage that stress. Cortisol is made in the section of the adrenal cortex called the zona fasciculata. 
• Dehydroepiandrosterone (DHEA). DHEA helps produce some sex hormones. It is sent to the ovaries, where it forms estrogen, or the testes, where it forms androgen. DHEA is produced in the zona reticularis area of the adrenal cortex.