Related Research Articles
In inorganic chemistry, bicarbonate is an intermediate form in the deprotonation of carbonic acid. It is a polyatomic anion with the chemical formula HCO−
3.
Digestion is the breakdown of large insoluble food compounds into small water-soluble components so that they can be absorbed into the blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into the blood stream. Digestion is a form of catabolism that is often divided into two processes based on how food is broken down: mechanical and chemical digestion. The term mechanical digestion refers to the physical breakdown of large pieces of food into smaller pieces which can subsequently be accessed by digestive enzymes. Mechanical digestion takes place in the mouth through mastication and in the small intestine through segmentation contractions. In chemical digestion, enzymes break down food into the small compounds that the body can use.
Chyme or chymus is the semi-fluid mass of partly digested food that is expelled by a person's or another animal's stomach, through the pyloric valve, into the duodenum.
Alkalosis is the result of a process reducing hydrogen ion concentration of arterial blood plasma (alkalemia). In contrast to acidemia, alkalemia occurs when the serum pH is higher than normal. Alkalosis is usually divided into the categories of respiratory alkalosis and metabolic alkalosis or a combined respiratory/metabolic alkalosis.
Gastric acid, gastric juice, or stomach acid is a digestive fluid formed within the stomach lining. With a pH between 1.5 and 3, gastric acid plays a key role in digestion of proteins by activating digestive enzymes, which together break down the long chains of amino acids of proteins. Gastric acid is regulated in feedback systems to increase production when needed, such as after a meal. Other cells in the stomach produce bicarbonate, a base, to buffer the fluid, ensuring a regulated pH. These cells also produce mucus – a viscous barrier to prevent gastric acid from damaging the stomach. The pancreas further produces large amounts of bicarbonate and secretes bicarbonate through the pancreatic duct to the duodenum to neutralize gastric acid passing into the digestive tract.
Parietal cells (also known as oxyntic cells) are epithelial cells in the stomach that secrete hydrochloric acid (HCl) and intrinsic factor. These cells are located in the gastric glands found in the lining of the fundus and body regions of the stomach. They contain an extensive secretory network of 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 signalling from both central and local modulators.
Achlorhydria and hypochlorhydria refer to states where the production of hydrochloric acid in gastric secretions of the stomach and other digestive organs is absent or low, respectively. It is associated with various other medical problems.
Digestive enzymes are a group of enzymes that break down polymeric macromolecules into their smaller building blocks, in order to facilitate their absorption into the cells of the body. Digestive enzymes are found in the digestive tracts of animals and in the tracts of carnivorous plants, where they aid in the digestion of food, as well as inside cells, especially in their lysosomes, where they function to maintain cellular survival. Digestive enzymes of diverse specificities are found in the saliva secreted by the salivary glands, in the secretions of cells lining the stomach, in the pancreatic juice secreted by pancreatic exocrine cells, and in the secretions of cells lining the small and large intestines.
The anion gap is a value calculated from the results of multiple individual medical lab tests. It may be reported with the results of an electrolyte panel, which is often performed as part of a comprehensive metabolic panel.
Metabolic alkalosis is a metabolic condition in which the pH of tissue is elevated beyond the normal range (7.35–7.45). This is the result of decreased hydrogen ion concentration, leading to increased bicarbonate, or alternatively a direct result of increased bicarbonate concentrations. The condition typically cannot last long if the kidneys are functioning properly.
In physiology, base excess and base deficit refer to an excess or deficit, respectively, in the amount of base present in the blood. The value is usually reported as a concentration in units of mEq/L (mmol/L), with positive numbers indicating an excess of base and negative a deficit. A typical reference range for base excess is −2 to +2 mEq/L.
Hyperchloremic acidosis is a form of metabolic acidosis associated with a normal anion gap, a decrease in plasma bicarbonate concentration, and an increase in plasma chloride concentration. Although plasma anion gap is normal, this condition is often associated with an increased urine anion gap, due to the kidney's inability to secrete ammonia.
The gastric glands are glands in the lining of the stomach that play an essential role in the process of digestion. All of the glands have mucus-secreting foveolar cells. Mucus lines the entire stomach, and protects the stomach lining from the effects of hydrochloric acid released from other cells in the glands.
Acid–base homeostasis is the homeostatic regulation of the pH of the body's extracellular fluid (ECF). The proper balance between the acids and bases in the ECF is crucial for the normal physiology of the body—and for cellular metabolism. The pH of the intracellular fluid and the extracellular fluid need to be maintained at a constant level.
Contraction alkalosis refers to the increase in blood pH that occurs as a result of fluid losses. The change in pH is especially pronounced with acidic fluid losses caused by problems like vomiting.
Acid–base imbalance is an abnormality of the human body's normal balance of acids and bases that causes the plasma pH to deviate out of the normal range. In the fetus, the normal range differs based on which umbilical vessel is sampled. It can exist in varying levels of severity, some life-threatening.
Foveolar cells or surface mucouscells are mucus-producing cells which cover the inside of the stomach, protecting it from the corrosive nature of gastric acid. These cells line the gastric mucosa. The mucus-secreting cells of the stomach can be distinguished histologically from the intestinal goblet cells, another type of mucus-secreting cell.
Salicylate poisoning, also known as aspirin poisoning, is the acute or chronic poisoning with a salicylate such as aspirin. The classic symptoms are ringing in the ears, nausea, abdominal pain, and a fast breathing rate. Early on, these may be subtle, while larger doses may result in fever. Complications can include swelling of the brain or lungs, seizures, low blood sugar, or cardiac arrest.
Distal renal tubular acidosis (dRTA) is the classical form of RTA, being the first described. Distal RTA is characterized by a failure of acid secretion by the alpha intercalated cells of the distal tubule and cortical collecting duct of the distal nephron. This failure of acid secretion may be due to a number of causes. It leads to relatively alkaline urine, due to the kidney's inability to acidify the urine to a pH of less than 5.3.
Delta ratio, or "delta-delta", is a formula that can be used to assess elevated anion gap metabolic acidosis and to evaluate whether a mixed acid–base disorder is present. The anion gap (AG) without potassium is calculated first and if a metabolic acidosis is present, results in either a high anion gap metabolic acidosis (HAGMA) or a normal anion gap acidosis (NAGMA). A low anion gap is usually an oddity of measurement, rather than a clinical concern.
References
- ↑ Margaret E. Smith; Dion G. Morton (18 November 2011). The Digestive System: Systems of the Body Series. Elsevier Health Sciences UK. p. 52. ISBN 978-0-7020-4841-8.
- ↑ Margaret E. Smith; Dion G. Morton (18 November 2011). The Digestive System: Systems of the Body Series. Elsevier Health Sciences UK. p. 85. ISBN 978-0-7020-4841-8.
- ↑ Taton, DF; Hamar, D; Lewis, LD (15 February 1984). "Evaluation of ammonium chloride as a urinary acidifier in the cat". Journal of the American Veterinary Medical Association . 184 (4): 433–6. PMID 6698874.
- ↑ McGavin, MD., Zachary, JF. Pathologic Basis of Veterinary Disease, Fourth Edition, Mosby, 2007, pp. 680–686.
- ↑ Seldin, Donald W.; Rector, Floyd C. (1972). "The generation and maintenance of metabolic alkalosis". Kidney International. 1 (5): 306–321. doi: 10.1038/ki.1972.43 . PMID 4600132.
- Gennari, F. John (2005). Acid-base disorders and their treatment. Informa Health Care. p. 217. ISBN 978-0-8247-5915-5.
 | This cardiovascular system article is a stub. You can help Wikipedia by expanding it. |
 | This human digestive system article is a stub. You can help Wikipedia by expanding it. |