| Abstract: |
The parathyroid glands were discovered by Ivar Viktor Sandström (1852-1889), a Swedish medical student, in 1880. It was the last major organ to be recognized in humans.The body has four parathyroid glands. They are small, pea-sized glands, located in the neck just behind the butterfly-shaped thyroid gland. Two parathyroid glands lie behind each ’wing’ of the thyroid gland.The parathyroid glands release a hormone called parathyroid hormone. This hormone helps to control the levels of two salts in the body: calcium and phosphorus.Normally, parathyroid hormone release is triggered when the levels of calcium in the blood are low. When the calcium levels rise and are back to normal, parathyroid hormone is suppressed.Parathyroid hormone has a number of effects in the body:• It causes the release of calcium from bones.• It causes calcium to be absorbed (taken up into the blood) from the intestine.• It stops the kidneys from excreting (getting rid of) calcium in the urine.• It causes the kidneys to excrete phosphate in the urine.In hyperparathyroidism, the parathyroid glands make and release too much parathyroid hormone. Generally, this means that calcium levels in the blood become too high.Calcium and phosphorus combine to make calcium phosphate in the body. This is the chief material that gives hardness and strength to bones and teeth. Calcium is also needed as part of the complex mechanism that
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