Parietal cell - wikipedia Parietal cell This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. ( March 2009 ) Parietal cell Human parietal cells ( pink staining ) - stomach Control of stomach acid Details Identifiers Latin exocrinocytus parietalis MeSH Gastric + Parietal + Cells Code TH H3. 04.02. 1.00033 Anatomical terminology ( edit on Wikidata ) Parietal cells ( also known as oxyntic or delomorphous cells ), are the epithelial cells that secrete hydrochloric acid ( HCl ) and intrinsic factor. These cells are located in the gastric glands found in the lining of the fundus and in the body of the stomach. They contain an extensive secretory network ( called canaliculi ) from which the HCl is secreted by active transport into the stomach. The enzyme hydrogen potassium ATPase ( H / K ATPase ) is unique to the parietal cells and transports the H against a concentration gradient of about 3 million to 1, which is the steepest ion gradient formed in the human body. Parietal cells are primarily regulated via histamine, acetylcholine and gastrin signaling from both central and local modulators ( see ' Regulation ' ). Contents 1 Secretion of hydrochloric acid 1.1 Synthesis 1.2 Regulation 2 Intrinsic factor 3 Canaliculus 4 Diseases of parietal cells 5 See also 6 References 7 External links Secretion of hydrochloric acid Synthesis Hydrochloric acid is formed in the following manner : Hydrogen ions are formed from the dissociation of carbonic acid. Water is a very minor source of hydrogen ions in comparison to carbonic acid. Carbonic acid is formed from carbon dioxide and water by carbonic anhydrase. The bicarbonate ion ( HCO ) is exchanged for a chloride ion ( Cl ) on the basal side of the cell and the bicarbonate diffuses into the venous blood, leading to an alkaline tide phenomenon. Potassium ( K ) and chloride ( Cl ) ions diffuse into the canaliculi. Hydrogen ions are pumped out of the cell into the canaliculi in exchange for potassium ions, via the H / K ATPase. These receptors are increased in number on luminal side by fusion of tubulovesicles during activation of parietal cells and removed during deactivation. This receptor maintains a million fold difference in proton concentration. ATP is provided by the numerous mitochondria. As a result of the cellular export of hydrogen ions, the gastric lumen is maintained as a highly - acidic environment. The acidity aids in digestion of food by promoting the unfolding ( or denaturing ) of ingested proteins. As proteins unfold, the peptide bonds linking component amino acids are exposed. Gastric HCl simultaneously activates pepsinogen, an endopeptidase that advances the digestive process by breaking the now - exposed peptide bonds, a process known as proteolysis. Regulation Parietal cells secrete acid in response to three types of stimuli : Histamine, stimulates H histamine receptors ( most significant contribution ). Acetylcholine, from parasympathetic activity via the vagus nerve and enteric nervous system, stimulating M receptors. Gastrin, stimulating CCK2 receptors ( least significant contribution, but also causes histamine secretion by local ECL cells ) Activation of histamine through H receptor causes increases intracellular cAMP level while Ach through M receptor and gastrin through CCK2 receptor increases intracellular calcium level. These receptors are present on basolateral side of membrane. Increased cAMP level results in increased protein kinase A. Protein kinase A phosphorylates proteins involved in the transport of H / K ATPase from the cytoplasm to the cell membrane. This causes resorption of K ions and secretion of H ions. The pH of the secreted fluid can fall by 0.8. Gastrin primarily induces acid - secretion indirectly, increasing histamine synthesis in ECL cells, which in turn signal parietal cells via histamine release / H2 stimulation. Gastrin itself has no effect on the maximum histamine - stimulated gastric acid secretion. The effect of histamine, acetylcholine and gastrin is synergistic, that is, effect of two simultaneously is more than additive of effect of the two individually. It helps in non-linear increase of secretion with stimuli physiologically. Intrinsic factor Parietal cells also produce intrinsic factor. Intrinsic factor is required for the absorption of vitamin B in the diet. A long - term deficiency in vitamin B can lead to megaloblastic anemia, characterized by large fragile erythrocytes. Pernicious anaemia results from autoimmune destruction of gastric parietal cells, precluding the synthesis of intrinsic factor and, by extension, absorption of Vitamin B. Pernicious anemia also leads to megaloblastic anemia. Atrophic gastritis, particularly in the elderly, will cause an inability to absorb B and can lead to deficiencies such as decreased DNA synthesis and nucleotide metabolism in the bone marrow. Canaliculus A canaliculus is an adaptation found on gastric parietal cells. It is a deep infolding, or little channel, which serves to increase the surface area, e.g. for secretion. The parietal cell membrane is dynamic ; the numbers of canaliculi rise and fall according to secretory need. This is accomplished by the fusion of canalicular precursors, or `` tubulovesicles '', with the membrane to increase surface area, and the reciprocal endocytosis of the canaliculi ( reforming the tubulovesicles ) to decrease it. Diseases of parietal cells Immunofluorescence staining pattern of gastric parietal antibodies on a stomach section Peptic ulcers can result from over-acidity in the stomach. Antacids can be used to enhance the natural tolerance of the gastric lining. Antimuscarinic drugs such as pirenzepine or H antihistamines can reduce acid secretion. Proton pump inhibitors are more potent at reducing gastric acid production since that is the final common pathway of all stimulation of acid production. In pernicious anemia, autoantibodies directed against parietal cells or intrinsic factor cause a reduction in vitamin B absorption. It can be treated with injections of replacement vitamin B ( methylcobalamin, hydroxocobalamin or cyanocobalamin ). Achlorhydria is another autoimmune disease of the parietal cells. The damaged parietal cells are unable to produce the required amount of gastric acid. This leads to an increase in gastric pH, impaired digestion of food and increased risk of gastroenteritis. See also Gastric chief cell Digestion Gastroesophageal reflux disease Discovery and Development of Proton Pump Inhibitors References Jump up ^ Boulpaep, Walter ( 2009 ). Medical Physiology. Philadelphia : Saunders. pp. 898 -- 899. ISBN 978 - 1 - 4160 - 3115 - 4. Jump up ^ `` Gastric acid secretion - Homo sapiens ''. KEGG. Retrieved June 1, 2011. Jump up ^ Waldum, Helge L., Kleveland, Per M., et al. ( 2009 ) ' Interactions between gastric acid secretagogues and the localization of the gastrin receptor ', Scandinavian Journal of Gastroenterology, 44 : 4,390 -- 393 Jump up ^ Kleveland PM, Waldum HL, Larsson M. Gastric acid secretion in the totally isolated, vascularly perfused rat stomach. A selective muscarinic - 1 agent does, whereas gastrin does not, augment maximal histamine - stimulated acid secretion. Scand J Gastroenterol 1987 ; / 22 : / 705 � 13. Jump up ^ Ganong 's Review of Medical Physiology 24th edition. LANGE. External links Illustration of Chief cells and Parietal cells at anatomyatlases.org The Parietal Cell : Mechanism of Acid Secretion at vivo.colostate.edu Histology image : 11303loa -- Histology Learning System at Boston University - Digestive System : Alimentary Canal : fundic stomach, gastric glands, lumen '' Physiology : 6 / 6ch4 / s6ch4_8 - Essentials of Human Physiology Physiology : 6 / 6ch4 / s6ch4_14 - Essentials of Human Physiology Parietal cell antibody Antibody to GPC Physiology of the gastrointestinal system GI tract Upper Exocrine Chief cells Pepsinogen Parietal cells Gastric acid Intrinsic factor Foveolar cells HCO Mucus Goblet cells Mucus Processes Swallowing Vomiting Fluids Saliva Gastric acid Lower Enteric nervous system Submucous plexus Myenteric plexus Endocrine / paracrine G cells gastrin D cells somatostatin ECL cells Histamine enterogastrone : I cells CCK K cells GIP S cells secretin Enteroendocrine cells Enterochromaffin cell APUD cell Fluids Intestinal juice Processes Segmentation contractions Migrating motor complex Borborygmus Defecation Either / both Processes Peristalsis ( Interstitial cell of Cajal Basal electrical rhythm ) Gastrocolic reflex Digestion Accessory Fluids Bile Pancreatic juice Processes Enterohepatic circulation Abdominopelvic Peritoneal fluid Cells in humans derived from endoderm Foregut Respiratory Pneumocyte Type 1 Type 2 Club cell Goblet cell Digestive Stomach Enteroendocrine cell G cell Delta cell Enterochromaffin - like cell Gastric chief cell Parietal cell Foveolar cell Intestine Enteroendocrine cell Gastric inhibitory polypeptide S cell Delta cell Cholecystokinin Goblet cell Paneth cell Tuft cell Enterocyte Microfold cell Liver Hepatocyte Hepatic stellate cell ( Kupffer cell from mesoderm ) Gallbladder Cholecystocyte Exocrine pancreas Centroacinar cell Pancreatic stellate cell Islets of Langerhans alpha cell beta cell delta cell F cell ( PP cell epsilon cell Pharyngeal pouch Thyroid gland Follicular cell Parathyroid gland Parathyroid chief cell Oxyphil cell Hindgut / cloaca Urothelial cells Retrieved from `` https://en.wikipedia.org/w/index.php?title=Parietal_cell&oldid=797723683 '' Categories : Animal cells Human cells Acid secreting cells Stomach Hidden categories : Articles needing additional references from March 2009 All articles needing additional references Talk Contents About Wikipedia Català Čeština Dansk Español فارسی Français Galego Italiano עברית Қазақша Nederlands 日本 語 Norsk Polski Português Русский Slovenščina Svenska Türkçe 粵語 中文 Edit links This page was last edited on 28 August 2017, at 20 : 30. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: where does the atp needed to secrete hcl come from
Answer: the parietal cells