Editing Parietal cell (section)

{{Short description|Epithelial cell in the stomach}}
{{More citations needed|date=March 2009}}
{{Infobox cell
| Name        = Parietal cell
| Latin       = exocrinocytus parietalis
| Image       = File:Parietal cell.png
| Caption     = A parietal cell.
| Image2      = Control-of-stomach-acid-sec.png
| Caption2    = Control of stomach acid
| Precursor   =
| System      =
| Location = [[Stomach]]
| Function = [[Gastric acid]], [[intrinsic factor]] secretion
}}
'''Parietal cells''' (also known as '''oxyntic cells''') are [[epithelium|epithelial cells]] in the [[stomach]] that secrete [[hydrochloric acid]] (HCl) and [[intrinsic factor]].  These [[Cell (biology)|cells]] are located in the [[gastric glands]] found in the [[gastric mucosa|lining]] of the [[Stomach#Sections|fundus]] and [[Stomach#Sections|body]] regions of the stomach.<ref name=BMJ2014>{{cite journal|last1=Hunt|first1=A|last2=Harrington|first2=D|last3=Robinson|first3=S|title=Vitamin B12 deficiency.|journal=BMJ|date=4 June 2014|volume=349|pages=g5226|pmid=25189324|doi=10.1136/bmj.g5226|s2cid=28782021|url=http://frankhollis.com/temp/BMJ%20B12%20deficiency%20review.pdf|url-status=dead|archive-url=https://web.archive.org/web/20170312074341/http://frankhollis.com/temp/BMJ%20B12%20deficiency%20review.pdf|archive-date=12 March 2017|access-date=9 May 2018}}{{free access}}</ref> They contain an extensive secretory network of [[#Canaliculus|canaliculi]] from which the HCl is secreted by [[active transport]] into the stomach. The enzyme [[hydrogen potassium ATPase]] (H<sup>+</sup>/K<sup>+</sup> ATPase) is unique to the parietal cells and transports the H<sup>+</sup> against a [[concentration]] gradient of about 3 million to 1,{{Citation needed|date=October 2019}} which is the steepest{{Citation needed|date=October 2019}}<!-- Need a specific reference for this exact claim: i.e. the claim that it's the steepest of ALL ion gradients in the human body --> ion gradient formed in the human body.  Parietal cells are primarily [[#Regulation|regulated]] via [[histamine]], [[acetylcholine]] and [[gastrin]] signalling from both central and local modulators.