The ultimopharyngeal body, or ultimobranchial body or ultimobranchial gland is a small organ found in the neck region of many animals. In humans, it develops from the fourth pharyngeal pouch into the parafollicular cells of the thyroid to produce calcitonin. It may not develop in DiGeorge syndrome.
Structure
The ultimopharyngeal body is a small organ of the neck. It is found in many animals. In humans, it develops into other tissues.
Development
In humans, the ultimopharyngeal body is an embryological structure, and is a derivative of the ventral recess of the fourth pharyngeal pouch. It is technically from the fifth pharyngeal pouch, but this is rudimentary and merges with the fourth. Endoderm cells migrate and associate with the ultimopharyngeal body during development.
Function
In humans, the ultimopharyngeal body develops into the parafollicular cells of the thyroid. In other animals, the ultimopharyngeal body may produce calcitonin.