Pituitary Gland
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1 AnswerSome pituitary tumors secrete an excess amount of a certain type of hormone. If they do so, it's those chemical effects on your body that lead to the discovery of the pituitary tumor. In other cases, the pituitary tumor can grow quite large in size, and then it can start affecting the tissues around it. If it grows upward towards the optic nerves, it can cause visual loss and people can lose their peripheral vision. If it compresses the normal gland, then you start losing function of the normal gland and you could have hormonal effects due to that. You could also have a combination of these symptoms. If you have hormonal effects and a large tumor, you could have visual loss. You can have an excess of certain hormones, and a diminishment of certain other key hormones. In some cases, people may have a magnetic resonance imaging (MRI) scan or a computed axial tomography (CAT) scan for some unrelated reason and there will be an incidental discovery of a pituitary tumor.
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1 AnswerNewYork-Presbyterian Hospital answered
When a 50-year-old Costa Rican man began to lose his sight, became increasingly weak, then collapsed early last year, he was taken to the local emergency room. Doctors there discovered a tumor on his pituitary gland the size of a tangerine. The growth was benign but was pressing on his optic nerve and encroaching on other parts of his brain. Surgeons on the island tried removing the tumor using a new, minimally invasive approach – operating through the patient's nose – but got only a fraction of the tumor. As his condition deteriorated he contacted neurosurgeons at several major US hospitals in a search for one who would be willing to try the same, minimally invasive procedure. Each doctor he spoke to told him this approach was impossible, that it would be necessary to remove the tumor by opening up his skull. Then, through the internet, he found Theodore Schwartz, MD, and Vijay K. Anand, MD.
Dr. Schwartz, a neurosurgeon, and Dr. Anand, an otolaryngologist work as a team at NewYork-Presbyterian Hospital/Weill Cornell Medical Center, and each year perform 50 to 60 minimally invasive surgeries on the skull base, the complex area of the brain behind the face where the pituitary gland is located. Drs. Schwartz and Anand studied this patient's medical records, told him they would be able to get his tumor out, and after he flew to New York they removed the growth through his nose. Two weeks after the operation he was back on his feet, his vision was returning, and now, a year later, he is fully recovered. -
4 AnswersDr. Michael Roizen, MD , Internal Medicine, answeredThe pituitary gland is a small, oval gland (about the size of a pea) that's located at the base of your skull. It has two sides, the posterior and the anterior. The anterior comes up from the back of the mouth and grows up into the brain, while the posterior protrudes down from the hypothalamus in the brain to sit on a bone called the "Turkish Saddle." It's a bone that sits at the base of the skull and holds the pituitary—almost like a ball resting in a socket. Although the posterior secretes a couple hormones, the anterior gets all the glory for secreting hormones you probably recognize, if not by name, by their function—including:
• luteinizing hormone, which plays a part in menstrual cycles and pregnancy and tells men when to release testosterone;
• prolactin, which helps women produce milk and plays a role in maintaining immune system cells in both genders (women have a lot more prolactin at all times than men);
• thyroid stimulating hormone, which stimulates the thyroid gland to produce more thyroid hormone that helps regulate metabolism and blood pressure;
• adrenal corticotrophic hormone, which stimulates: the adrenal cortex to produce cortisone that helps regulate metabolism, blood pressure, and response to stress;
• aldosterone that helps regulate water metabolism and blood pressure; and the sex hormone it produces (such as testosterone for women);
• and growth hormone, which, uh, helps you grow.
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1 AnswerDr. Jack Merendino, MD , Endocrinology Diabetes & Metabolism, answeredAny disease process or injury that can damage the pituitary can cause pituitary failure. The most common problem is a tumor of the pituitary gland. These are common and almost always benign. In most cases they do not cause pituitary failure, and it is much more common that they either cause no symptoms or cause over-production of one or more pituitary hormones. If a tumor is very large, however, it may cause failure of pituitary function by compressing or displacing the normal tissue.
Pituitary surgery is itself a common cause of pituitary failure. If a pituitary tumor has to be removed surgically, there is damage or destruction of the remaining pituitary tissue, and the gland may not function properly. The same is true for radiation therapy. In this case pituitary failure may happen gradually, often over the space of several years after the radiation was given.
Pituitary infarction is a common cause of pituitary failure. "Infarction" means death because the blood supply is cut off. Pituitary infarction most often occurs in settings where there is a sudden drop in blood pressure. The blood flow to the pituitary gland is somewhat tenuous, and an abrupt fall in blood pressure may cause the gland to die from inadequate blood flow with the oxygen and nutrients necessary to keep the tissue alive. A common situation in which this occurs in if there is hemorrhage with childbirth. In pregnancy the pituitary gland enlarges. If there is hemorrhage with delivery, blood flow may be cut off at a time when the pituitary gland is vulnerable. Pituitary failure following this is called "Sheehan’s syndrome."
An accident with head trauma or even sudden severe movement of the head may cause pituitary failure. The blood vessels to the gland may be torn in this setting and the gland may die as a result.
The final common cause of pituitary failure is an autoimmune disease that damages or destroys pituitary tissue. This is less common than in some other endocrine organs, such as the thyroid, where under- or over-activity may result, or the insulin-producing cells of the pancreas, where type 1 diabetes is the consequence. But an autoimmune process affecting the entire pituitary, or in some cases just one hormone, is now well recognized as a problem.
Other, less common causes of pituitary failure can occur, including metastatic tumors to the gland, infection of the pituitary or surrounding tissue, or certain "granulomatous" diseases. -
1 AnswerDr. Mehmet Oz, MD , Cardiology (Cardiovascular Disease), answeredThe pituitary gland is located at the base of the brain. Watch the animation to learn about its role in ovulation.
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1 AnswerThe anterior lobe of the pituitary gland makes the following hormones:
- Adrenocorticotropic hormone (ACTH).
- Thyroid-stimulating hormone (TSH), which causes the thyroid gland to produce two hormones, triiodothyronine (T3) and thyroxine (T4), which help control the body's metabolism.
- Luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which control the production of testosterone, estrogen, sperm, and egg maturation and release.
- Growth hormone (GH), which is a major participant in control of several complex physiologic processes, including growth and metabolism.
- Prolactin, which stimulates the production of breast milk and is necessary for normal milk production during breastfeeding.
- The posterior pituitary lobe releases two hormones that are produced in the hypothalamus:
- Oxytocin, which is responsible for stimulation of milk ejection (milk letdown) and for stimulation of uterine smooth muscle contraction at birth.
- Vasopressin (ADH), which is the primary regulator of body water.
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1 AnswerThe pituitary gland itself consists of a larger anterior lobe that makes the following hormones: adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), growth hormone (GH) and Prolactin. The posterior lobe releases two hormones, oxytocin and vasopressin (ADH) that are produced in the hypothalamus. The hypothalamus relays signals from many parts of the brain to the pituitary, which in turn sends its own messages to various parts of the body.
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1 AnswerPituitary hormone deficiency is usually caused by a benign pituitary tumor pressing on and destroying the cells of the pituitary gland. All of the hormones except prolactin can be replaced by medications—pills, injections, nasal spray, skin patches and/or skin gel, depending on the type of hormone.