Anterior Pituitary: What It Is & Function


The anterior pituitary gland is one of the main parts of the endocrine system, which regulates the body’s metabolism and other important functions. The word “anterior” refers to it being near the front of your brain, while “posterior” refers to its location behind the pituitary gland.

What is the anterior pituitary?

The anterior pituitary is the portion of the pituitary gland that produces hormones. The anterior pituitary is part of the neurohypophysis. It lies at the base of your brain, below your hypothalamus, and above your optic chiasm (where one optic nerve crosses over to another). The anterior pituitary has two important functions:

Anterior Pituitary: What It Is & Function

  • It produces hormones that control other bodily systems, including reproduction, growth, and metabolism.
  • A stalk connects it to the hypothalamus by an extension called the hypothalamic-hypophyseal tract. This link allows information from outside sources to reach the hormone-producing cells in your brain’s hypothalamus so they can influence production levels when necessary.

What is the pituitary gland?

It is a small gland that sits at the base of the brain. It comprises the anterior and posterior lobes of the endocrine system.

The main function of this gland is to control other glands in your body, including those that make hormones such as thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), prolactin, growth hormone (GH), and luteinizing hormone (LH).

What hormones does the anterior pituitary secrete?

The anterior pituitary releases six hormones that all have different functions:

  • Growth hormone (GH): GH is released into the bloodstream in response to low blood glucose, which signals your body that you need energy. It also increases muscle mass and bone density and promotes cell regeneration.
  • Prolactin (PRL): PRL stimulates milk production in breastfeeding women and inhibits it in those who aren’t; it also helps regulate other hormones, including thyroid-stimulating hormone (TSH) and luteinizing hormone (LH).
  • Thyroid-stimulating hormone (TSH): TSH regulates the production of thyroid hormones by stimulating your thyroid gland. These hormones affect your metabolism, heart rate, and other bodily functions related to growth or energy expenditure.
  • Luteinizing hormone (LH): LH triggers ovulation—the release of an egg from one of your ovaries—and stimulates testosterone production in men during puberty. In menopausal women whose ovaries have stopped producing estrogen but still produce follicle-stimulating hormone (FSH), it may lead to increased sex drive!
  • Testosterone: Testosterone is responsible for many physical changes during puberty, such as increased muscle mass and bone density. It also promotes cell regeneration and increases energy levels.
  • Cortisol: Cortisol is a steroid hormone produced by your adrenal glands that helps regulate the body’s response to stress. It increases blood sugar levels, boosting energy and activating the brain’s reward center.

 How does the anterior pituitary interact?

The anterior pituitary interacts with other organs and glands. The hypothalamus is the master gland and regulates the pituitary by releasing hormones that travel to it through blood vessels. These hormones then stimulate or inhibit activity in the anterior pituitary, affecting how active other glands are or become.

Where is the anterior pituitary located?

The anterior pituitary is located in the sella turcica, also known as the sphenoid bone. Also known as the pituitary gland, it is a small structure that sits at the base of your brain. The pituitary gland produces hormones that control growth and development.

How big is the anterior pituitary?

It is quite small in size, weighing only 1 to 2 grams. It is roughly the size of a pea.

But despite being so small, this gland produces several hormones that affect all major organ systems in your body.

What conditions are related to the anterior pituitary?

Many conditions are related to the anterior pituitary gland. The most common of these are:

  • Hypopituitarism – A condition where you do not produce enough hormones from your pituitary gland, which decreases body functions such as growth or hormone production.
  • Hyperpituitarism – A condition where you produce too many certain hormones from your pituitary gland.
  • Pituitary tumors (adenomas) – These can be benign or malignant and may require treatment with surgery or medication to remove them completely.

Hypopituitarism conditions

It is a condition in which the pituitary gland is not functioning properly. This can be caused by damage to or dysfunction of the anterior pituitary through radiation damage, surgery, or other conditions.

When this happens, it can cause a variety of symptoms, including:

  • Decreased levels of hormones that are produced by your pituitary gland (like cortisol and growth hormone)
  • Low blood pressure and fatigue due to low levels of adrenocorticotropic hormone (ACTH), which stimulates your adrenal glands to produce more cortisol
  • Abnormally low body temperature due to reduced thyroid-stimulating hormone (TSH) and TSH-releasing factor from your hypothalamus.
  • Increased levels of prolactin and growth hormone in your blood can lead to lactation in both men and women. Low levels of testosterone or estrogen are due to decreased production by the gonads.

Hyperpituitarism conditions

  • Pituitary adenomas are tumors that grow in the pituitary gland and may cause hypersecretion of hormones from the anterior pituitary. These tumors usually grow slowly and spread to other parts of the body.
  • Pituitary hyperplasia is an overgrowth of normal tissue in your pituitary gland, which results in too much hormone production by your anterior lobe. This can result from a tumor or another condition that affects how quickly cells divide and multiply (like infection).
  • A growth hormone-producing tumor causes pituitary gigantism on your pituitary gland, which makes you taller than normal for your age group (before puberty). After puberty, it can also make you overweight because it stimulates growth throughout your body—including muscles and bones.
  • Pituitary dwarfism occurs when there’s not enough growth hormone (GH) produced by either type II or type III GH receptors due to a mutation on one copy of each gene; this causes both types II & III receptors needed for normal height development during childhood years; instead, these patients have small bodies with short arms and legs despite having normal-sized skulls with no brain abnormalities found upon examination.

Pituitary gland tumors (adenomas)

Pituitary adenomas are noncancerous tumors that can grow on the pituitary gland. The pituitary is a small endocrine gland located at the base of your brain. It produces hormones that control other glands in your body, including reproductive and adrenal glands.

The exact cause of pituitary adenomas isn’t known, but they usually start as slow-growing cells in the anterior lobe of the pituitary gland. To help understand how these tumors develop:

  • Anterior means front part or beginning (think “anterior” in front).
  • Lobe means division or area around something larger (think “lobes”).

A common symptom associated with an anterior pituitary adenoma is an overproduction of growth hormone, which causes gigantism if it occurs during childhood; acromegaly if it occurs during adulthood; increased thirst; increased hunger; high blood pressure; enlargement of certain bones such as those in hands or feet; fatigue; headaches due to increased pressure inside skull from enlarging bone mass from acromegaly patients being treated with medications such as cabergoline or bromocriptine.

What tests can check my anterior pituitary?

  • Blood tests
  • Urine tests
  • Brain scans (CT, MRI, X-ray)
  • Ultrasound
  • Electrocardiogram (EKG)


Now that you know more about the anterior pituitary, you will better understand what it is and how it functions. It’s important to note that if any symptoms are present in your body, it is always best to consult with a physician before making any changes in medication or treatment plans.