Adrenal Cortex

What is the adrenal cortex?

The cortex is the outer part of your adrenal gland. It releases hormones that support your well-being.

It consists of three layers:

• Zona glomerulosa (outer layer).
• Zona fasciculata (middle layer).
• Zona reticularis (innermost layer).

Are there other parts of the adrenal gland?

The cortex takes up 85% of adrenal gland tissue, but it’s not the only part. This gland also contains a small inner section (medulla). The adrenal gland resembles the size and shape of a fortune cookie.

Where are the adrenal glands?

You have two adrenal glands, one on top of each kidney. Your kidneys sit just below your ribcage.

What is the function of the adrenal cortex?

The adrenal cortex produces hormones that support vital organ functioning. Each adrenal cortex layer produces different hormones.

What adrenal cortex hormones develop in the zona glomerulosa?

The zona glomerulosa produces aldosterone. This hormone affects your body in many ways, by:

• Causing water retention.
• Increasing levels of sodium in your intestines.
• Ridding your body of excess potassium through urine output.

What adrenal cortex hormones develop in the zona fasciculata?

The zona fasciculata produces cortisol. This hormone serves many functions. It:

• Controls blood sugar levels.
• Supports the breakdown of carbohydrates, proteins and fats (metabolism).
• Regulates blood pressure.
• Suppresses inflammation.
• Regulates your sleep-wake cycle.
• Raises glucose levels when the body is under stress.

What adrenal cortex hormones develop in the zona reticularis?

The zona reticularis produces androgens (sex hormones). The primary androgen is DHEA. In all genders, androgens support:

• Bone density.
• Puberty.
• Red blood cell production.
• Sexual function.

In people assigned male at birth, androgens are responsible for:

• Vocal cord lengthening that leads to a deeper voice.
• Facial and chest hair growth.
• Sperm development.

In people assigned female at birth, androgens:

• Regulate menstruation.
• Have a role in conception and pregnancy.
• Minimize bone loss.

What is the anatomy of the adrenal cortex?

You have two adrenal glands — one on top of each kidney. They contain the cortex, the largest part of the gland, and the medulla, the smaller inner part. Your adrenal gland is highly vascular, with as many as 50 arterial branches providing its blood supply.

When does the adrenal cortex develop?

Your adrenal cortex and the rest of your adrenal gland develop in the early weeks of gestation. At this time, the gland has two sections: the fetal and adult definitive zones. The fetal zone shrinks and disappears after you're born.

The gland’s abundant blood supply supports its development, making it possible to produce adrenal cortex hormones and connect to nearby nerves.

What conditions and disorders affect the adrenal cortex?

There are many conditions and disorders, some of which are rare, that can affect the adrenal cortex. These conditions can be functional, meaning they cause abnormally high hormone levels or nonfunctional, meaning they do not produce hormones.

Adrenal disorders and conditions include:

• Addison's disease (adrenal insufficiency).
• Adrenal tumors.
• Adrenocortical carcinoma (cancer in the adrenal cortex).
• Congenital adrenal hyperplasia.
• Conn's syndrome (primary aldosteronism).
• Cushing's syndrome (hypercortisolism).
• Hyperaldosteronism.

What are the symptoms of adrenal cortex disorders?

Damage from adrenal gland disorders occurs slowly, so you might not notice symptoms at first. When you do, they gradually continue worsening until you receive appropriate therapies.

You may experience symptoms affecting your:

• Appetite.
• Blood pressure.
• Blood sugar levels.
• Heart health.
• Mood.
• Muscle strength.
• Skin.
• Weight.

What treatments might I need for adrenal cortex disease?

There are many available therapies. The most appropriate therapies for you depend on your diagnosis and symptom severity.

Care may include:

• Hormone replacement therapy: Taking bioidentical hormones helps restore hormones to expected levels if you can’t produce enough on your own. For example, you may take hydrocortisone pills to replace cortisol.
• Lifestyle changes: Adopting healthy habits can reduce strain on your adrenal glands. You may wish to limit alcohol consumption, eat a low-sodium diet or quit smoking and using tobacco products.
• Medications: If your body is producing abnormally high levels of hormones, prescription drugs can help. Care may include spironolactone to block the effects of aldosterone or ketoconazole to slow the production of cortisol.
• Tumor and cancer treatments: Tumors may need to be surgically removed, especially larger ones or those that produce excess hormones. Radiation and chemotherapy may be necessary for issues like adrenocortical carcinoma.
• Plastic and reconstructive surgery: These procedures repair structures affected by abnormal hormone levels. For example, people with congenital adrenal hyperplasia may experience enlarged or ambiguous genitalia that surgery can correct.

How can I take care of my adrenal cortex?

Taking good care of yourself optimizes gland functioning, including your adrenal cortex. This includes:

• Living an active lifestyle with regular physical activity.
• Eating a diet that’s rich in nutrients and consuming plenty of water.
• Managing stress with meditation or yoga.
• Receiving preventive care, including regular physical exams from your primary care provider.

A note from Cleveland Clinic

The adrenal cortex is the outer part of your adrenal gland. It produces hormones that support vital organ functions and bodily processes. Many conditions can affect the adrenal cortex. Some cause the overproduction of hormones, while others limit hormone production. Taking good care of your health optimizes adrenal cortex functioning and lowers your risk of tumors and other disorders.