OverviewWhat is the anterior pituitary?The anterior pituitary is the front lobe of your pituitary gland, which is a small, pea-sized gland located at the base of your brain below your hypothalamus. Your pituitary gland is a part of your endocrine system and controls the function of several other endocrine glands. Show
Your pituitary gland is made of two lobes: the anterior (front) lobe and posterior (back) lobe. The anterior pituitary creates and releases over six different hormones, which regulate various cellular processes including:
What is the pituitary gland?Your pituitary gland is a small gland located at the base of your brain below your hypothalamus. It’s in charge of making many different important hormones. Your pituitary gland also tells other endocrine system glands to release hormones. Your pituitary gland is connected to your hypothalamus through a stalk of blood vessels and nerves. This is called the pituitary stalk. Through the stalk, your hypothalamus communicates with your pituitary gland and tells it to release certain hormones. Your hypothalamus is the part of your brain that controls functions like blood pressure, heart rate, body temperature and digestion. Your pituitary gland makes the following hormones:
Your pituitary gland doesn’t produce and release all of these hormones continuously. Most are released in bursts every one to three hours, alternating between periods of activity and inactivity. Another term to describe the release of hormones from your pituitary gland is pulsatile. Your pituitary gland may secrete some hormones based on your circadian rhythm. What is the endocrine system?Your endocrine system is a network of several glands that create and secrete (release) hormones. A gland is an organ that makes one or more substances, such as hormones, digestive juices, sweat or tears. Endocrine glands release hormones directly into your bloodstream. Hormones are chemicals that coordinate different functions in your body by carrying messages through your blood to your organs, muscles and other tissues. These signals tell your body what to do and when to do it. The following organs and glands make up your endocrine system:
FunctionWhat hormones are secreted by the anterior pituitary?Your anterior pituitary produces and releases (secretes) six main hormones:
How does the anterior pituitary interact with other organs and glands?Your anterior pituitary interacts directly with your hypothalamus since your hypothalamus regulates it by secreting the “releasing hormones" somatostatin and dopamine through blood vessels in the pituitary stalk. These releasing hormones either stimulate or inhibit (prevent) the creation and release of anterior pituitary hormones. Your hypothalamus and anterior pituitary are in constant communication with each other. The anterior pituitary hormones interact with and affect several different organs, glands and tissues in your body, including:
AnatomyWhere is the anterior pituitary located?Your pituitary gland is located at the base of your brain, behind the bridge of your nose and directly below your hypothalamus. It sits in a small chamber or pouch in the sphenoid bone called the sella turcica. Your pituitary gland is made of two lobes that touch each other. The anterior pituitary is in the front and is facing the front of your head, whereas the posterior pituitary is the back lobe of your pituitary gland, meaning it is facing the back of your head. How big is the anterior pituitary?Your pituitary gland is only about 1/3 of an inch in diameter in total — about the size of a pea. The anterior pituitary is bigger than the posterior pituitary and accounts for about 80% of the total weight of your pituitary gland. What is the anterior pituitary made of?The anterior pituitary is made of cell clusters that produce six hormones and release them into your bloodstream. Different types of cell clusters create and release different hormones, including:
Conditions and DisordersSeveral different conditions are related to issues with the anterior pituitary since it produces so many different hormones. In general, the majority of conditions related to the anterior pituitary are due to hypopituitarism (underactive pituitary gland) or hyperpituitarism (overactive pituitary gland). In these conditions, your anterior pituitary either produces too little or too much of one or more hormones. Hypopituitarism and hyperpituitarism are generally caused by one of the following conditions or situations:
Hypopituitarism conditionsConditions that are the result of lower-than-normal levels of one or more anterior pituitary hormones include:
Hyperpituitarism conditionsConditions that are the result of higher-than-normal levels of one or more anterior pituitary hormones include:
Pituitary gland tumors (adenomas)A pituitary adenoma is a growth or tumor on your pituitary gland. Most pituitary adenomas are slow-growing and benign (noncancerous). Adenomas can put pressure on normal pituitary cells and keep them from working properly, leading to hypopituitarism, especially when they are large. They can also release extra pituitary hormones, leading to hyperpituitarism (pituitary hormone excess). Pituitary adenomas make up 10% to 15% of all tumors that develop within the skull. They are found in about 77 out of 100,000 people, although researchers believe that they actually occur in as many as 20% of people at some point in their lives. However, many pituitary adenomas, especially very small ones, don’t cause serious symptoms and are never discovered. What tests can check the health of my anterior pituitary?If you’re experiencing symptoms related to anterior pituitary issues, your healthcare provider may order tests to check one or more of your anterior pituitary hormone levels, depending on what your symptoms are. These tests are usually blood tests. If your test results come back abnormal, your provider may suggest undergoing an imaging test such as an MRI (magnetic resonance imaging) to take a look at your pituitary gland. A note from Cleveland Clinic Since your anterior pituitary is responsible for several different hormones that affect many aspects of your body and health, it can be difficult to pinpoint if certain symptoms are a result of issues with your anterior pituitary. If you’re ever experiencing new or concerning symptoms, it’s important to talk to your healthcare provider. They can usually run some simple tests to assess your health. What hormone from the anterior pituitary gland stimulates the thyroid?The hypothalamus releases thyrotropin-releasing hormone (TRH) into the hypothalamic-hypophyseal portal system to the anterior pituitary gland. TRH stimulates thyrotropin cells in the anterior pituitary to the release of thyroid-stimulating hormone (TSH).
Which hormone is released by the anterior pituitary gland?The anterior pituitary gland produces six major hormones: (1) prolactin (PRL), (2) growth hormone (GH), (3) adrenocorticotropic hormone (ACTH), (4) luteinizing hormone (LH), (5) follicle-stimulating hormone (FSH), and (6) thyroid-stimulating hormone (TSH) (Table 401e-1).
Which hormone is secreted by the anterior pituitary gland for the purpose of stimulating the thyroid gland to produce T3 and T4?When the level of thyroid hormones (T3 & T4) drops too low, the pituitary gland produces Thyroid Stimulating Hormone (TSH) which stimulates the thyroid gland to produce more hormones. Under the influence of TSH, the thyroid will manufacture and secrete T3 and T4 thereby raising their blood levels.
What is the stimulus for hormone release from the anterior pituitary gland?The gonadotropic hormones LH and FSH are synthesized and secreted by gonadotrophs of the anterior pituitary in response to stimulation by gonadotropin-releasing hormone (GnRH).
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