Proton pump inhibitor - Proton pump inhibitor Proton pump inhibitors is a group of drugs whose main action is pronounced and long-lasting reduction of gastric acid production. The group followed another group of pharmaceuticals with similar action called H2 antagonists. Proton pump inhibitors act by blocking the hydrogen-potassium adenosine triphosphatase enzyme system (the so called proton pump ) of the gastric parietal cell. Hence the enzyme inhibited is the terminal stage in gastric acid production. These drugs are utilized in the treatment of many conditions such as: duodenal and gastric ulcers Zollinger-Ellison syndrome Erosive reflux oesophagitis. Clinically used proton pump inhibitors: Omeprazole (brand names: Prilosec, Losec) Lansoprazole (brand names: Prevacid) Esomeprazole (brand names: Nexium) Pantoprazole (brand names: Protonix) Rabeprazole (brand names: Aciphex).
Proton pump - Proton pump 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. In bacteria, mitochondria and other ATP-producing organelles, reducing equivalents provided by electron transfer or photosynthesis power this translocation of protons. For example, the translocation of protons by cytochrome c oxidase is powered by reducing equivalents provided by reduced cytochrome c. In the plasma membrane proton ATPase and in the ATPase proton pumps of other cellular membranes, ATP itself powers this transport. The F0F1 ATP synthase of mitochondria and the CF1 ATP synthetase of chloroplasts, in.
Proton - Proton This article is about the subatomic particle. For the Russian rocket design, see Proton (rocket). For the Malaysian automobile manufacturer, see Proton (car). In physics, the proton is a subatomic particle with a positive fundamental electric charge of 1.6 × 10-19 coulomb, a mass of 938 MeV (1.6726231 × 10-27 kg, or about 1800 times that of an electron) and a half-life of about 1033 years. The nucleus of the most common isotope of the hydrogen atom, H, is a single proton. The nuclei of other atoms are composed of neutrons and protons held together by the strong nuclear force. The number of protons in the nucleus determines the chemical properties of the atom and what chemical element it is. Protons are classified as baryons.
Pharmacology - Nutrition 1.11 For the Respiratory System 1.12 For the Ear, Nose and Oropharynx 1.13 For the Eye 1.14 For Allergic Disorders 1.15 For the Skin 1.16 For Contraception 1.17 For Obstetrics and Gynaecology 1.18 For Neoplastic disorders 1.19 For diagnostics 1.20 Drugs found to have side effects and no longer used 1.21 Types of Pharmacological Preparations 2 See also Classes of medicinal products For the Gastrointestinal Tract (see also Digestive system) antacid, reflux suppressant, antiflatulent, antidopaminergic, antispasmodic, proton pump inhibitor, H2 antagonists, cytoprotectant, prostaglandin analogue, laxative, antidiarrhoeal, bile acids For the Cardiovascular System ACE inhibitor, cardiac glycoside, phosphodiesterase inhibitor, nitrate, antiarrhythmic, beta-receptor blocker, antianginal, diuretic, antihypertensive, calcium channel blocker, alpha blocker, vasodilator, peripheral activator, anticoagulant, heparin, antiplatelet drug, fibrinolytic, haemostatic drug, hypolipidaemic agent, statin. For the Central Nervous System hypnotic, anxiolytic,.
List of biochemistry topics - crossover - cryptobiology - C-terminus - cuticula - cyclic electron flow - Cyclic nucleotide - cysteine - cytoplasm - cytoskeleton - cytosol - cytotoxic T cell - covalent bond - Covalent radius - Crystallography - Crystal structure - Cytosine D decarboxylation reaction - Denatured - denaturation - dendrite - dendritic cell - dendritic spine - deoxyribose - developmental biology - dialysis - Diffusion - Dimer - Diploid - Disulfide bridge - Disulfide bond - DNA - DNA replication - DNA sequence - DNA topology - DNA virus - Deuterium - Disaccharide - Dissociation constant - Domain - double helix - Drosophila - drugs E electrochemical potential - electron - electron capture - Electron configuration - electron shell - electron volt - Electronegativity - Electrophile - electron microscopy - electron transport chain.
H2 antagonist - antagonist drugs (such as cimetidine) work by blocking the H2 subtype of histamine receptors. These are different receptors from those involved in the allergic response. Since the advent of proton pump inhibitors, use of these drugs to treat ulcers has declined..
GERD - gastric acid secretion so avoiding these helps. Foods high in fats and smoking reduce lower esophageal sphincter competence so avoiding these tends to help as well. Having more but smaller meals also reduces the risk of GERD as it means there is less in the stomach at any one time. Drug treatment Antacids before meals or symptomatically after symptoms begin can reduce gastric acidity. Gastric H2 receptor blockers such as ranitidine can reduce gastric secretion of acid. Proton pump inhibitors such as omeprazole are even more effective in reducing gastric acid secretion..
Aripiprazole - the treatment of schizophrenia. A warning has gone out recently because of this drug's name. The '-azole' ending of this drug name makes this drug sound like it is one of the proton pump inhibitors (such as omeprazole, pantoprazole, lansoprazole) which are used in treating peptic ulcer disease. However, aripiprazole and these drugs are in an entirely different class of drugs altogether and confusing the two can lead to some unnecessary side effects. Aripiprazole was develeloped by Otsuka Pharmaceutical Co., Ltd and is manufactured by the Bristol Myers Squibb Company (NYSE: BMY). Aripiprazole was approved by the FDA on November 15, 2002. Like most other antipsychotics, long term use of aripiprazole can lead to tardive dyskinesia. External Links Aripiprazole Offers Hope for Schizophrenia Abilify - The Internet Drug Database http://www.abilify.com/ This.
Reflux oesophagitis - (especially young children). Barrett Oesophagus (sometimes referred to as Barrett's Disease) or dysplasia (a pre-cancerous condition). In the adult, oesophagitis causes discomfort which is treated with antacids or some medications such as H2 receptor antagonists (such as ranitidine, or famotidine) or proton pump inhibitors (such as omeprazole, or pantoprozole). Monitoring and assessment of patients with reflux is often performed via Gastroscopy / Endoscopy which involves the insertion of a thin optical scope into the oesophagus and stomach (while the patient is sedated) in order to assess the state of the oesaphagus and stomach. Biopsies can be peformed during gastroscopy and these may show: Oedema and basal hyperplasia (non-specific inflammatory changes) Lymphocytic inflammation (non-specific) Neutrophilic inflammation (usually either reflux or Helicobacter gastritis) Eosinophilic inflammation (usually reflux) Goblet cell intestinal metaplasia or Barretts.
Peptic ulcer - Helicobacter infection will eventually lead to an ulcer and a larger proportion of people will get non-specific discomfort or gastritis. Anti-acid treatments such as cimetidine, ranitidine and antacids may reduce symptoms but will not clear the infection. Bismuth compounds may actually reduce or even clear organisms. The most effective treatments are combinations of antibiotics (Erythromycin, Ampicillin, Tetracycline, Metronidazole) and proton pump inhibitors. Treatment of Helicobacter usually leads to clearing of infection, relief of symptoms and eventual healing of ulcers. Recurrence of infection can occur and retreatment may be required. The diagnosis of Helicobacter can be by: Biopsy Breath tests Direct culture Direct detection of urease activity. Rarely now, some ulcers perforate and require surgery. The possibility of other causes of ulcers, notably malignancy needs to be kept in mind..
Flagellum - structure, passing through protein rings in the cell's membranes that act as bearings. Gram-positive organisms have 2 rings, one in the cell wall and one in the cell membrane. Gram-negative organisms have 4 rings, 2 in the cell wall and 2 in the cell membrane. The bacterial flagellum is driven by a rotary engine composed of protein, located at the flagellum's anchor point on the inner cell membrane. The engine is powered by proton motive force, i.e., by the flow of protons across the bacterial cell membrane due to a concentration gradient set up by the cell's metabolism (in Vibrio species the motor is a sodium ion pump, rather than a proton pump). The rotor transports protons across the membrane, and is turned in the process. The rotor by itself can.
Electron transfer chain - as NADH or succinate, shuttles these electrons across the mitochondrial membrane creating an electrical and chemical gradient, and through the proton driven chemistry of the ATP synthase (aka the F0F1 particle), generates adenosine triphosphate (ATP). There are five complexes normally associated with the electron transfer chain. Complex I - NADH dehydrogenase, also called NADH coenzyme Q reductase. Complex II - Succinate - coenzyme Q reductase. Complex III - Coenzyme Q - cytochrome c reductase. Complex IV - Cytochrome c oxidase. Complex V - ATP synthase, also known as the F0F1 particle. All of these are proteolipid complexes, with the first four containing either flavins, iron-sulfur clusters, copper centers, or heme moieties. Complexes I, III, and IV are proton pumps. Complex II is part of the Krebs cycle and does not pump.
Diabetes dictionary - lists and explains terms connected with diabetes. A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A ACE inhibitor Acetohexamide - A pill taken to lower the level of glucose (sugar) in the blood. Only some people with Type II diabetes take these pills. See also: Oral hypoglycemic agents. One of the sulfonylurea drugs. Acetone Acidosis - An acidic condition in the blood. If prolonged, or severe, it can cause coma and death. For a person with diabetes, this can be caused by insufficient glucose absorption (eg, from inadequate insulin) and metabolic ketosis. It can lead to diabetic ketoacidosis. A medical emergency. See also: Diabetic ketoacidosis. Acute - Happens for a limited period of.
ATP synthase - through the 1970s, Paul Boyer developed his binding change, or flip-flop, mechanism, which postulated that ATP synthesis is coupled with a conformational change in the ATP synthase generated by rotation of the gamma subunit. John E. Walker crystallized the ATP synthase and was able to determine that Boyer's conformational model was essentially correct. In the crystal structure, the F1 particle can be seen to be composed of a cylinder of 6 subunits, alternating alpha and beta subunits, that form a ring around an asymmetrical gamma subunit. Facilitated diffusion of protons causes the F0 particle to rotate, rotating the gamma subunit of F1, while the major F1 subunits are fixed in place. This rotation forces a conformational change in the F1 particle, eventually leading to the synthesis of ATP. For elucidating this.
Chemiosmotic hypothesis - of electrochemical capacitor, using the energy of NADH and FADH2 to create a pH gradient across the mitochondrial membrane and that this energy was used by a reversible proton pump, the ATP synthase, to create ATP. This was a radical proposal at the time, and not well accepted. The prevailing view was that the energy of electron transfer was stored as a stable high potential intermediate, a chemically more conservative concept. The problem with the older paradigm is that no high energy intermediate was ever found, and the evidence for proton pumping by the complexes of the electron transfer chain grew too great to be ignored. Eventually the weight of evidence began to favor the chemiosmotic hypothesis, and in 1978, Peter Mitchell was awarded the Nobel Prize in Chemistry. see also:.
Coenzyme Q - cytochrome c reductase - it catalyzes the reduction of cytochrome c by accepting reducing equivalents from Coenzyme Q (CoQ): CoQH2+ 2 Fe+3-cytochrome c → CoQ + 2 Fe+2-cytochrome c In the process, protons are translocated across the mitochondrial membrane. Therefore, the bc1 complex is a proton pump. Compared to the other major proton pumping subunits of the electron transport chain, the number of subunits found can be small, as small as three polypeptide chains. This number does increase, and as many as eleven subunits can be found in higher animals. The major prosthetic groups in the complex are a pair of cytochromes, the b cytochrome and the c1 cytochrome, and a two iron, two sulfur iron-sulfur cluster. More information can be found on the Cytochrome bc1 complex page..
Cytochrome - within membranes in an organized way, the redox reactions are carried out in the proper sequence for maximum efficiency. Other membrane-bound and soluble complexes and cofactors are involved in the chain of redox reactions, with the additional net effect that protons are transported across the membrane. The resulting transmembrane proton gradient (protonmotive force) is used to power cellular processes that require energy (such as rotation of flagella, transport of molecules across the membrane, and synthesis of ATP). Several kinds of cytochrome exist and can be distinguished by spectroscopy, exact structure of the heme group, inhibitor sensitivity, and reduction potential: Cytochrome a Cytochrome a3 Cytochrome b Cytochrome c Cytochrome c1 Cytochome f See the articles on mitochondria and chloroplasts for more information on electron transport and related metabolic pathways..
Transmembrane ATPase - and 2 K+ ions outward per ATP hydrolyzed, for the Na+/K+ exchanger. Transmembrane ATPases harness the chemical potential energy of ATP, because they perform work: they transport solutes in a direction opposite to their thermodynamically preferred direction of movement—that is, from the side of the membrane where they are in low concentration to the side where they are in high concentration. This process is considered active transport. The ATP synthetase (or ATP synthase) of mitochondria and chloroplasts is an anabolic enzyme that harnesses the energy of a transmembrane proton gradient as an energy source for adding an inorganic phosphate group to a molecule of adenosine diphosphate (ADP) to form a molecule of adenosine triphosphate (ATP). ATP synthetase can also function in reverse; that is, use energy released by ATP hydrolysis to.
Oxidative phosphorylation - and in eukaryotes it is the inner of the two mitochondrial membranes. NADH and FADH2, electron carrier molecules that were "loaded" during the citric acid cycle, are used in an intricate mechanism (involving NADH-Q reductase, cytochrome c oxidase, and cytochrome reductase) to pump H+ across the membrane against a proton gradient. A large protein complex called ATP synthase is embedded in that membrane and enables protons to pass through in both directions; it generates ATP when the proton moves with (down) the gradient, and it costs ATP to pump a proton against (up) the gradient. Because protons have already been pumped into the intermembrane space against the gradient, they now can flow back into the mitochondrial matrix via the ATP synthase, generating ATP in the process. The reaction is: ADP3- +.
Nuclear isomer - isomer is a metastable state of an atom caused by the excitation of a proton or neutron in its nucleus so that it requires a change in spin before it can release its extra energy. Contrast this with the definition of a chemical isomer, the more common use of the word. Also contrast with the meaning of isotope, in which the difference is the number of neutrons in the nucleus. Metastable isomers of a particular atom are usually designated with an "m" (or, in the case of atoms with more than one isomer, 2m, 3m, and so on). This designation is usually placed after the atomic symbol and number of the atom (e.g., Co-58m), but is sometimes placed as a superscript before (e.g., mCo-58). Most nuclear isomers are very unstable, and.
