<Tr> <Th> Code </Th> <Td> TH H3. 04.02. 1.00033 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terminology (edit on Wikidata) </Td> </Tr> <P> 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'). </P> <P> Hydrochloric acid is formed in the following manner: </P>

Where does the atp needed to secrete hcl come from