ultimobranchial body

(redirected from Ultimobranchial bodies)
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ultimobranchial body

One of two embryonic pharyngeal pouches usually considered as rudimentary fifth pouches. They become separated from the pharynx and incorporated into the thyroid gland, where they give rise to parafollicular cells that secrete calcitonin, a hormone that lowers the blood calcium level.
See also: body


pertaining to the tissue originating from the fifth pharyngeal pouch of the embryo.

ultimobranchial body
the glandular tissue originating from the fifth branchial pouch which combines with the buccal cavity outgrowth to form the thyroid and contributes calcitonin-secreting cells to the gland.
ultimobranchial duct cysts
derived from remnants of the ultimobranchial body and found in the thyroid gland.
ultimobranchial tumor
a neoplasm containing thyroid C cells.