Hormone and Its Function

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 osteoclasts- accelerating 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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