The ultimopharyngeal body, or ultimobranchial body or ultimobranchial gland is a small organ found in the neck region of many

animal Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motilit ...

s. In humans, it develops from the

fourth pharyngeal pouch In the embryonic development of vertebrates, pharyngeal pouches form on the endodermal side between the pharyngeal arches. The pharyngeal grooves (or clefts) form the lateral ectodermal surface of the neck region to separate the arches. The pouch ...

into the

parafollicular cell Parafollicular cells, also called C cells, are neuroendocrine cells in the thyroid. The primary function of these cells is to secrete calcitonin. They are located adjacent to the thyroid follicles and reside in the connective tissue. These cells a ...

s of the

thyroid The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...

to produce

calcitonin Calcitonin is a 32 amino acid peptide hormone secreted by parafollicular cells (also known as C cells) of the thyroid (or endostyle) in humans and other chordates. in the ultimopharyngeal body. It acts to reduce blood calcium (Ca2+), opposing the ...

. It may not develop in

DiGeorge syndrome DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a syndrome caused by a microdeletion on the long arm of chromosome 22. While the symptoms can vary, they often include congenital heart problems, specific facial features, frequent in ...

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

. It is technically from the fifth pharyngeal pouch, but this is rudimentary and merges with the fourth. It develops into the

s of the

. The cells that give rise to the parafollicular cells are derivatives of

endoderm Endoderm is the innermost of the three primary germ layers in the very early embryo. The other two layers are the ectoderm (outside layer) and mesoderm (middle layer). Cells migrating inward along the archenteron form the inner layer of the gast ...

. Endoderm cells migrate and associate with the ultimopharyngeal body during development.

Function

In humans, the ultimopharyngeal body develops into the

s of the

. These secrete

. In other animals, the ultimopharyngeal body may produce calcitonin.

Clinical significance

The ultimopharyngeal body may not develop in

History

The ultimopharyngeal body may also be known as the ultimobranchial body or the ultimobranchial gland.

References

External links

* * {{Authority control Embryology Human head and neck