PARATHYROID GLANDS
Parathyroid glands are located in close anatomical relation to the thyroid gland, usually on its posterior surface.
The parathyroid glands are four small endocrine glands, associated to the thyroid gland, about the size of a grain of rice. They have a “sensor” role detecting any drop in blood calcium, no matter how small it may be.
Each such drop in calcium causes a corresponding amount of parathyroid hormone release, in order to maintain calcium levels within the narrow normal limits.
Parathyroid hormone is a hormone secreted by the parathyroid glands with a goal to maintain calcium and phosphorus levels at normal levels.
The latter is achieved by PTH in cooperation with four other hormones, namely; Klotho, Calcitonin, FGF23 and Vitamin D, all of which together mobilize a complex endocrine mechanism involving four organs: the parathyroid glands, the bones, the kidneys and the gastrointestinal tract along with the liver.
When the secretion and/or action of parathyroid hormone is increased, the condition is called hyperparathyroidism, while when the secretion and/or action of parathyroid hormone is decreased, the condition is called hypoparathyroidism. Both conditions disturb calcium metabolism.