Parathyroid or parathyroid glands are very small structures that belong to the endocrine system, these are located in the neck area just at the back of the thyroid gland. These glands fulfill the function of keeping the calcium contained in the body under control, including the calcium found in the bones and in the blood.
It should be noted that calcium is the most important element in our body because it is used to keep under various monitoring systems, reason why it is very carefully regulated.
The parathyroid gland is shaped similar to a lentil, while it is approximately 5x3x3 mm in size and its average weight is 30 mg each. The tonality of these is variable and can range from yellow, reddish or brownish tones, in terms of its consistency it is very soft. The lower parathyroid glands are related to the lower thyroid artery and the recurrent laryngeal nerve. While the superior glands are closely related to the superior thyroid artery. They are irrigated by voluminous arteries, compared to their size, which is why large hemorrhages usually occur in surgical procedures.
From a histological point of view, the thyroid glands are covered by a capsule and are composed of three types of cells, the main cells are those that are responsible for the production of parathyroid hormone, followed by oxyphilic cells and aqueous cells However, the functions of the latter are not known. As for the parathyroid hormone, it intervenes in the control of calcium and phosphorus homeostasis, in addition to bone physiology.
These glands are secreted by the main cells of the parathyroid gland, it is a polypeptide of 84 amino acids that has an approximate molecular weight of 9500 Da. Among the functions that it must fulfill are the following:
- It makes the absorption process of calcium, vitamin D and phosphate easier; in conjunction with in the intestine.
- It increases the resorption of calcium from the bones, through the production of more osteoclasts from the mesenchymal stem cells that are located in the bone marrow, slowing down the process of their conversion into osteoblasts.
