Editing Parafollicular cell (section)

== Function ==
Parafollicular cells secrete [[calcitonin]], a hormone that participates in the regulation of [[calcium metabolism]]. Calcitonin lowers blood levels of calcium by inhibiting the [[bone resorption|resorption of bone]] by [[osteoclast]]s, and its secretion is increased proportionally with the concentration of calcium.<ref name=williams>{{cite book | vauthors = Melmed S, Polonsky KS, Larsen PR, Kronenberg HM | title = Williams Textbook of Endocrinology | date = 2011 | publisher = Saunders | pages = 1250–1252 | isbn = 978-1437703245 | edition = 12th }}</ref>

Parafollicular cells are also known to secrete in smaller quantities several neuroendocrine peptides such as [[serotonin]], [[somatostatin]] or [[CGRP]].<ref>{{cite journal | vauthors = Zabel M | title = Ultrastructural localization of calcitonin, somatostatin and serotonin in parafollicular cells of rat thyroid | journal = The Histochemical Journal | volume = 16 | issue = 12 | pages = 1265–72 | date = December 1984 | pmid = 6152264 | doi = 10.1007/bf01003725 | s2cid = 7889687 }}</ref><ref>{{cite journal | vauthors = Barasch JM, Mackey H, Tamir H, Nunez EA, Gershon MD | title = Induction of a neural phenotype in a serotonergic endocrine cell derived from the neural crest | journal = The Journal of Neuroscience | volume = 7 | issue = 9 | pages = 2874–83 | date = September 1987 | pmid = 3305802 | url= | doi = 10.1523/JNEUROSCI.07-09-02874.1987 | pmc = 6569149 }}</ref><ref>{{cite journal | vauthors = Bernd P, Gershon MD, Nunez EA, Tamir H | title = Separation of dissociated thyroid follicular and parafollicular cells: association of serotonin binding protein with parafollicular cells | journal = The Journal of Cell Biology | volume = 88 | issue = 3 | pages = 499–508 | date = March 1981 | pmid = 7217200 | pmc = 2112761 | doi = 10.1083/jcb.88.3.499 }}</ref>  They may also have a role in regulating thyroid hormones production locally, as they express [[thyrotropin-releasing hormone]].<ref>{{cite journal | vauthors = Gkonos PJ, Tavianini MA, Liu CC, Roos BA | title = Thyrotropin-releasing hormone gene expression in normal thyroid parafollicular cells | journal = Molecular Endocrinology | volume = 3 | issue = 12 | pages = 2101–9 | date = December 1989 | pmid = 2516877 | doi = 10.1210/mend-3-12-2101 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Morillo-Bernal J, Fernández-Santos JM, Utrilla JC, de Miguel M, García-Marín R, Martín-Lacave I | title = Functional expression of the thyrotropin receptor in C cells: new insights into their involvement in the hypothalamic-pituitary-thyroid axis | journal = Journal of Anatomy | volume = 215 | issue = 2 | pages = 150–8 | date = August 2009 | pmid = 19493188 | pmc = 2740962 | doi = 10.1111/j.1469-7580.2009.01095.x }}</ref>