Ultimobranchial body

The ultimobranchial body ( Glandula ultimobranchialis ) is a small endocrine organ of vertebrates (vertebrata) with the exception of mammals . In birds , it is located at the entrance to the chest on the common carotid artery , is adjacent to the thyroid and epithelial bodies and is difficult to find due to its transparency and its very variable shape.

The cells of the organ, which are arranged in epithelial cords , form calcitonin . The ultimobranchial body arises from the 4th (sometimes also 5th) pharynx . In mammals, the organ is in the system of the thyroid incorporated and forms there the parafollikulär arranged C-cells .