Parathyroid gland

Parathyroid glands
Diagram showing structures in the human neck. The four green shaded areas represent the most common position of the parathyroid glands, which are generally four in number and situated behind the lateral lobes of the thyroid gland (shaded orange).
Thyroid and parathyroids as viewed from the front of the neck
Details
Precursor	Neural crest mesenchyme and third and fourth pharyngeal pouch endoderm
System	Endocrine
Artery	Superior thyroid artery, inferior thyroid artery,
Vein	Superior thyroid vein, middle thyroid vein, inferior thyroid vein,
Nerve	Middle cervical ganglion, inferior cervical ganglion
Lymph	Pretracheal, prelaryngeal, jugulodigastric lymph nodes
Identifiers
Latin	glandula parathyreoidea inferior, glandula parathyreoidea superior
MeSH	D010280
TA98	A11.4.00.001
TA2	3870
FMA	13890
Anatomical terminology [edit on Wikidata]

Parathyroid glands are small endocrine glands in the neck of humans and other tetrapods. Humans usually have four parathyroid glands, located on the back of the thyroid gland in variable locations. The parathyroid gland produces and secretes parathyroid hormone in response to low blood calcium, which plays a key role in regulating the amount of calcium in the blood and within the bones.

Parathyroid glands share a similar blood supply, venous drainage, and lymphatic drainage to the thyroid glands. Parathyroid glands are derived from the epithelial lining of the third and fourth pharyngeal pouches, with the superior glands arising from the fourth pouch and the inferior glands arising from the higher third pouch. The relative position of the inferior and superior glands, which are named according to their final location, changes because of the migration of embryological tissues.

Hyperparathyroidism and hypoparathyroidism, characterized by alterations in the blood calcium levels and bone metabolism, are states of either surplus or deficient parathyroid function.