Functions
The Parathyroid Gland regulates the calcium and phosphorus concentrations in the extra-cellular
fluid. The Parathyroid stimulates three processes: the mobilization of calcium in bone,
enhancing absorption of calcium from the small intestine and suppression of calcium loss in
urine. It also stimulates the active from of Vitamin D in the kidney.
Location
The Parathyroid Gland affects the bones and kidneys. They are located in the neck, near the
thyroid, with two glands on each side, for a total of 4 Parathyroid Glands in the human body.
Occasionally, some of the glands have been found in the chest and 8% of humans will have a
total of 3 to 5 Parathyroid Glands. The glands are the size of a pea and they weigh 1.6 grams.
Hormone and its Function
The Parathyroid hormone is known chemically as PTH. The hormone acts on the bones and
kidneys and it produces calcium and phosphorus. It secretes preprohormone into the blood by
exocytosis, which is packaged in the Golgi. Preprohormone is secreted as a linear protein made
up of 84 amino acids. The secretion stimulates an increase in calcium concentration in body
fluids and effects these four major functions in the human body: stimulation of osteoclastsaccelerating mineral turnover and release of calcium from bone, inhibits osteoblasts- reducing
the rate of calcium deposition in bone, enhances reabsorption of calcium in the kidney- reducing
urinary losses, and stimulating the formation and secretion of calcitroil in the kidneys- enhances
the digestive tract. PTH Therapy has been used on people with osteoporosis and has had a
proven effect on increasing bone densities in those with bone diseases.
Disorders
Primary Hyperparathyroidism is when the parathyroid gland grows to create a tumor. The
enlarged gland secretes hormones without proper regulation, resulting in elevated blood calcium
concentrations, kidney stones, and decalcification of bones. Secondary Hyperparathyroidism is
an excessive secretion of the parathyroid hormone, usually caused by kidney disease. This
disorder results in the decalcification of bones leading to “rubber bones”. Treatment for
Secondary Hyperparathyroidism includes PTH therapy, stimulating an increase in bone mass and
strength. Hypoparathyroidism results in a decrease of calcium and an increase of phosphorus in
the blood. Causes of this disorder are due to the removal of the parathyroid glands and it can
lead to tetany, convulsions, and can be life-threatening. Hypoparathyroidism treatments include
infusions of calcium and Vitamin D supplements to restore calcium into the blood.
PRIMARY HYPERPARATHYROIDISM
Symptoms
FATIGUE
EXHAUSTION
WEAKNESS
FEQUENT URINATION
URINATION AT NIGHT
BONE PAIN
BACK PAIN
CONSTIPATION
LOSS OF APPETITE
Associated Disorders
NEPHROLITHIASIS (KIDNEY STONES)
BLOOD IN URINE
BONE FRACTURE
GOUT
JOINT SWELLING
WEIGHT LOSS
ULCER
ULCERS
HYPERTENSION/DEPRESSION
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