body and parathyroid glands of the freshwater snake Natrix piscator in response to vitamin D3 administration.
Common stem cell theory--suggests that both tumours arise from common uncommitted stem cells derived from ultimobranchial
C cells arise from the ultimobranchial
body, which is derived from the fourth pharyngeal pouch, and they are found in the upper and middle areas of the thyroid lobes.
The first theory is the embryonic nest theory, which suggests that squamous cells are derived from embryonic remnants such as thyroglossal duct, thymic epithelium and ultimobranchial
We showed that CTAVN and solid cell nests of the thyroid gland are identical structures and indicated that CTAVN is an ultimobranchial
heterotopia secondary to an alteration in cardiac neural crest cell development.
The superior parathyroid gland and the ultimobranchial
body develop from the fourth branchial pouch, also in the vicinity of the piriform sinus.
10) The thyroid gland then descends to meet the lateral ultimobranchial
bodies; the fusion of these elements leads to the formation of the functional and mature thyroid gland by the third fetal month.
Cells from the neural crest descend to the ultimobranchial
body and finally migrate to amalgamate with the thyroid tissue and form the parafollicular cells (C cells).
1) As noted in the table, fourth branchial pouch anomalies virtually always occur on the left side, which is thought to be due to diminished growth of the right ultimobranchial