Endocrine System

Endocrine System

Your endocrine system works with your nervous system to control important bodily functions. The endocrine systems responsibilities include regulating growth, sexual development and function, metabolism and mood. The endocrine system also helps give your body the energy it needs to function properly. Endocrine glands secrete hormones into the bloodstream. Hormones are considered chemical messengers, coordinating your body by transferring information from one set of cells to another. Your endocrine system health can be affected by hormone imbalances resulting from impaired glands. A hormone imbalance can cause problems with bodily growth, sexual development, metabolism and other bodily functions. Endocrine system diseases or conditions include diabetes, growth disorders and osteoporosis.

Recently Answered

  • QWhat is hypoparathyroidism?
    2 Answers
    A
    RealAge
    A answered
    Hypoparathyroidism is a rare condition in which the four tiny parathyroid glands located in your neck do not produce sufficient amounts of parathyroid hormone (PTH). This hormone works in concert with vitamin D and another hormone, calcitonin (produced by the thyroid gland) to help control levels of calcium and phosphorus in your blood and bones. If you have hypoparathyroidism, your levels of calcium are too low and your levels of phosphorus are too high.

    Symptoms of hypoparathyroidism (most of which are due to too low levels of calcium) are wide-ranging and may include:
    • hair loss or dry hair
    • brittle nails
    • dry and/or scaly skin
    • cataracts
    • muscle cramps and/or spasms
    • pain in the face, legs and feet
    • painful menstruation (in women)
    • seizures
    • tingling in lips, fingers and toes
    • poor tooth development and/or weakened tooth enamel and tooth decay (in children)
    • headaches
    • vomiting
    • stunted growth and slow mental development (in children)
    • mood swings
    • hoarseness or voice changes
    • wheezing or other difficulty breathing
    The most common cause of hypoparathyroidism is damage to the parathyroid glands during surgery. Other medical treatments (radiation to the thyroid gland or some medications) may also cause the condition. In rare cases, hypoparathryoidism is caused by a genetic condition and infants are born with underdeveloped or no parathyroid glands. Certain underlying conditions (some cancers, neck trauma, Addison disease, Wilson’s disease or abnormal levels of iron or magnesium in the body) may also cause hypoparathyroidism.
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  • QWhich gonadotropins stimulate the ovaries?
    1 Answer
    A
    HealthyWomen
    A answered
    Gonadotropins are hormones -- luteinizing hormone (LH) and follicle stimulating hormone (FSH) -- that are given via injection to stimulate ovulation. Gonadotropins stimulate the ovaries directly. They include the following:
    • Human menopausal gonadotropin (HMG) is an injected medication. HMG (Repronex, Menopur) stimulates the ovaries directly, and is used for women who do not ovulate on their own.
    • Follicle stimulating hormone (FSH) directly stimulates the follicles and eggs to grow. FSH drug brand names include Gonal-F, Bravelle and Follistim.
    • Human chorionic gonadotropin (HCG) stimulates the egg to mature and the follicle to release its egg.
  • QHow does follicle-stimulating hormone (FSH) work?
    1 Answer
    A
    Dr. Daniel A. Dumesic, MD - Los Angeles, CA - Reproductive Endocrinology
    A Reproductive Endocrinology, answered on behalf of
    Under normal circumstances, the brain talks to the ovary, and the ovary communicates back to the brain in what is called a negative feedback inhibition system. In other words, the brain sends out hormones, including follicle-stimulating hormone (FSH), that travel into the blood to go to the ovary and make follicles grow. As the follicles grow, they produce estrogen, which returns through the circulation to the brain to tell the brain the follicle has sufficient stimulation. This clamps or suppresses FSH in a closed-loop system. If FSH can be pushed up in the blood, it can drive follicles to grow. This can be done by either inhibiting estrogen production by blocking its synthesis through an enzyme called aromatase or blocking the effects of estrogen in the brain by giving a medicine that is an anti-estrogen.
  • QWhen is a good time to measure male hormones in women?
    1 Answer
    A
    Dr. Daniel A. Dumesic, MD - Los Angeles, CA - Reproductive Endocrinology
    A Reproductive Endocrinology, answered on behalf of
    When doctors measure testosterone as an important male hormone in women, it’s measured in the early-morning hour or in the early part of the menstrual cycle. This is because testosterone levels change throughout the menstrual cycle by almost 25%. Women also have the highest levels in the morning, due to changes throughout the day in circulating levels of testosterone.

    Doctors can also measure free testosterone, which represents the amount of testosterone that is biologically active. This requires a specific blood test in certain laboratories that have assays developed to measure low amounts of free testosterone in a consistent and reproducible manner.
  • QWhat is secondary hyperparathyroidism?
    1 Answer
    A
    Dr. Jack Merendino, MD - Bethesda, MD - Endocrinology Diabetes & Metabolism
    A , Endocrinology Diabetes & Metabolism, answered
    Secondary hyperparathyroidism is a situation in which the parathyroid glands are producing a large amount of parathyroid hormone (PTH) to compensate for another problem. One can easily measure parathyroid hormone levels, and there is a “normal” range, but the range is really meaningless unless one also knows the blood calcium level. PTH is designed to raise the blood calcium. If the calcium level is low, the PTH should be high, so a higher-than-normal level means that the parathyroid glands are doing their job properly. This is what’s called secondary hyperparathyroidism -- the PTH levels are high, but they should be high because there is something else causing the blood calcium level to be low and the PTH goes up to try to compensate. 

    There are many causes of secondary hyperparathyroidism, but by far the most common is some form of vitamin D deficiency. Severe deficiency of standard 25-hydroxy-vitamin D3 levels (lets call this 25-D), which is the form of vitamin D that is usually measured in the blood, will sometimes cause secondary hyperparathyroidism. Much more commonly, the problem results from an inability of the body to convert this form of vitamin D to the more active form, 1,25-dihydroxy-vitamin D3 (we’ll call this 1,25-D). Conversion of 25-D to 1,25-D takes place in the kidney and many people with kidney problems -- sometimes even with what appear to be mild kidney problems -- can’t properly convert vitamin D and will develop secondary hyperparathyroidism. This condition results in a low blood calcium, a low blood phosphorus, a form of bone disease called osteomalacia, which is similar to osteoporosis but is corrected by 1,25-D, and possibly muscle weakness. This problem is surprisingly common and is frequently not recognized. Treatment with an oral form of active 1,25-D is highly effective at correcting the problem. When the 1,25-D level rises, and when the blood calcium is restored to normal, the PTH levels will also fall back into the normal range. 
     
  • QWhat is parathyroid hormone (PTH)?
    1 Answer
    A
    Dr. Jack Merendino, MD - Bethesda, MD - Endocrinology Diabetes & Metabolism
    A , Endocrinology Diabetes & Metabolism, answered
    Parathyroid hormone (PTH) is a key regulator of calcium and bone metabolism. PTH is made by the parathyroid glands which are located in the neck, just adjacent to the thyroid, though their function is completely separate from the thyroid. Most people have 4 glands, two on each side, one near the upper end of the thyroid gland on that side and one near the lower. Occasionally the glands may be found outside of their usual location, because they start out in one location during embryonic development and migrate or move as the fetus matures. Occasionally a parathyroid gland will seemingly get “stuck” somewhere along that migratory path. This is important only when a gland becomes overactive and needs to be removed surgically. It may be difficult to find a gland in an unexpected location unless you are a very skilled surgeon or do just the right radiographic tests to locate the gland. 

    The main role of PTH is to help keep the blood calcium level normal. This is critical because many physiologic processes require a precise calcium level in the blood. When the level of calcium in the blood starts to fall, the parathyroid glands release additional PTH.  PTH does three main things: 
    1. PTH increases the amount of active vitamin D in the body, which results in more calcium being absorbed from the food we eat.
    2. PTH causes the release of stored calcium from bone into the bloodstream.
    3. PTH causes calcium to be absorbed back into the body from urine that is being made. 
    These three actions together result in an increase in blood calcium levels. 

    Parathyroid hormone is used as a medication in two settings. First, one form of synthetic parathyroid hormone (drug name Forteo) is used to treat osteoporosis. Second, another form of parathyroid hormone (drug name NetPara) is used to treat hypoparathyroidism -- a condition of too little parathyroid hormone in the body. Hypoparathyroidism usually results from the accidental removal of all 4 parathyroid glands when one undergoes thyroid surgery, though there are other causes as well.
  • QWhat are typical testosterone levels in men?
    1 Answer
    A
    Dr. Mehmet Oz, MD - New York, NY - Cardiology (Cardiovascular Disease)
    A , Cardiology (Cardiovascular Disease), answered

    Below are standard testosterone levels for men of various age groups. Part of the challenge is that if you want to feel 30 when you are 50, you would theoretically want to get your testosterone level to that of a 30-year-old, but most practitioners would rather get you to where your age predicts. Nevertheless, if you feel like sludge, then some doctors will treat you even if your levels are in the low normal range for your age.

    Here are the typical ranges for men:

    • Age: 20-40 testosterone level: 400-1,080
    • Age: 40-50 testosterone level: 350-890
    • Age: 50-60 testosterone level: 250-750
    • Age: 70 or above testosterone level: 250-650

  • QHow do melatonin levels affect sleep?
    3 Answers
    A
    Natasha Turner, ND - Toronto, CA - Alternative & Complementary Medicine
    A , Alternative & Complementary Medicine, answered
    How do melatonin levels affect sleep?

    Melatonin is the hormone that is produced when we sleep in complete darkness, and it allows our bodies to go into deep, recuperative, immune-enhancing sleep. Watch naturopathic doctor Natasha Turner, ND, explain how melatonin affects sleep. 
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  • QWhat do my hormone levels say about my health?
    1 Answer
    A
    Dr. Michael Roizen, MD - Cleveland, OH - Internal Medicine
    A , Internal Medicine, answered
    When you have an acute disease or illness, your body shuts down production of some hormones. We know the mechanism of some of these. For others, we don't. One of the hormones that shut down is dehydroepiandrosterone (DHEA), a steroid produced by the adrenal glands. In fact, we now know that if you are a smoker and have a low DHEA level, your chance of dying in the next year is more than 150% higher than if you are a smoker and have a high DHEA level. That isn't because DHEA is so beneficial; it's because a low DHEA level is an indicator of acute illness in your system.
  • QWhat is the function of alpha cells in the pancreas?
    1 Answer
    A
    American Diabetes Association
    A answered
    An alpha cell is a type of cell in the pancreas. Alpha cells make and release a hormone called glucagon. The body sends a signal to the alpha cells to make glucagon when blood glucose falls too low. Then glucagon reaches the liver, where it tells it to release glucose into the blood for energy.