Gastric acid is, together with several enzymes and the intrinsic factor, one of the main secretions of the stomach. Chemically it is an acid solution consisting mainly of hydrochloric acid, but also containing small quantities of potassium chloride (KCl) and sodium chloride (NaCl). Intrinsic factor is a glycoprotein produced by the parietal cells of the stomach. ... Secretion is the process of segregating, elaborating, and releasing chemicals from a cell. ... In anatomy, the stomach (in ancient Greek στομάχι) is an organ in the alimentary canal used to digest food. ... The chemical hydrochloric acid is a highly acidic aqueous solution of hydrogen chloride (HCl). ... Overview The chemical compound potassium chloride (KCl) is a metal halide composed of potassium and chlorine. ... Sodium chloride, also known as common salt, table salt, or halite, is a chemical compound with formula NaCl. ...

Physiology

Diagram summarising control of stomach acid secretion, emphasising interaction between the body and antrum.

Gastric acid is produced by parietal cells. These cells are part of fundic glands in the gastric mucosa. The pH of gastric acid is 2-3 in the stomach lumen, the acidity being maintained by the proton pump, a H+/K+ ATPase. The parietal cell releases bicarbonate into the blood stream in the process. Parietal cells (also called oxyntic cells) are cells located in the stomach epithelium. ... The mucous membranes (or mucosa) are linings of ectodermic origin, covered in epithelium, that line various body cavities and internal organs. ... PH or ph or pH or Ph may be: In chemistry, pH is a measure of acidity. ... In anatomy, the lumen is the cavity or channel within a tube or tubular structure, such as the vascular lumen of a blood vessel, along which blood flows. ... A proton pump is an integral membrane protein that is capable of moving protons across the membrane of a cell, mitochondrion, or other subcellular compartment, thereby creating a difference or gradient in both pH and electrical charge (ignoring differences in buffer capacity) and tending to establish an electrochemical potential. ... ATPases are a class of enzymes that catalyze the decomposition of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and a free phosphate ion. ... Bicarbonate is a polyatomic ion whose formula is HCO3-. It is the intermediate form in the deprotonation of carbonic acid: removing the first proton from carbonic acid forms bicarbonate; removing the second proton leads to the carbonate ion. ...

Gastric acid production is regulated by both the autonomic nervous system and several hormones. The parasympathetic nervous system, via the vagus nerve, and the hormone gastrin stimulate the parietal cell to produce gastric acid, both directly acting on parietal cells and indirectly, through the stimulation of the secretion of the hormone histamine from enterochrommafine-like cells. Vasoactive intestinal peptide, cholecystokinin, and secretin all inhibit production. Anatomy and Physiology of the A.N.S. In contrast to the voluntary nervous system, the involuntary or autonomic nervous system is responsible for homeostasis, maintaining a relatively constant internal environment by controlling such involuntary functions as digestion, respiration, and metabolism, and by modulating blood pressure. ... Hormone is also the NATO reporting name for the Soviet/Russian Kamov Ka-25 military helicopter. ... The parasympathetic nervous system is one of two divisions of the autonomic nervous system. ... The vagus nerve is tenth of twelve cranial nerves and the only nerve that starts in the brainstem (somewhere in the medulla oblongata) and extends way down past the head, all the way down to the abdomen. ... In humans, gastrin is a hormone that stimulates secretion of gastric acid by the stomach. ... Histamine is a monoamine chemical involved in local immune responses. ... Cholecystokinin (CCK, previously pancreozymin) is a peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat and protein. ... Secretin is a hormone produced in the S cells of the duodenum in response to low duodenum pH and fatty acids in the duodenum to stimulate the secretion of bicarbonate from bicarbonate producing organs(liver, pancreas, Brunners glands) when the pH drops below a set value. ...

Role in disease

In atrophic gastritis and achlorhydria, there is decreased gastric acid production and thus decreased disinfectant properties of the gastric milieu, leading to an increased risk of infections of the digestive tract (such as the foodborne infection with Vibrio vulnificus). Achlorhydria is decreased production of gastric acid by the stomach. ... Disinfection The destruction of pathogenic and other kinds of microorganisms by physical or chemical means Disinfectants are chemical substances used to kill viruses and microbes (germs), such as bacteria and fungi. ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... Vibrio vulnificus is a rod-shaped bacterium of the genus Vibrio present in warm seawater. ...

In Zollinger-Ellison syndrome and hypercalcemia, there are increased gastrin levels, leading to excess gastric acid production, which can cause ulcers. Zollinger-Ellison syndrome is a disorder where increased levels of the hormone gastrin are produced, causing the stomach to produce excess hydrochloric acid. ... Hypercalcaemia is an elevated calcium level in the blood. ... In humans, gastrin is a hormone that stimulates secretion of gastric acid by the stomach. ... An ulcer (from Latin ulcus) is an open sore of the skin, eyes or mucous membrane, often caused by an initial abrasion and generally maintained by an inflammation and/or an infection. ...

In diseases featuring excess vomiting, patients develop hypochloremic metabolic alkalosis (decreased blood acidity by H⁺ and chlorine depletion). General Name, Symbol, Number chlorine, Cl, 17 Series halogens Group, Period, Block 17 (VIIA), 3, p Density, Hardness 3. ... General Name, Symbol, Number Hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1 (IA), 1 , s Density, Hardness 0. ... General Name, Symbol, Number chlorine, Cl, 17 Series halogens Group, Period, Block 17 (VIIA), 3, p Density, Hardness 3. ...

Pharmacology

The proton pump enzyme is the target of proton pump inhibitors, used to increase gastric pH in diseases which feature excess acid. Proton pump inhibitors are a group of drugs whose main action is pronounced and long-lasting reduction of gastric acid production. ...

See also

• Stomach